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Небесная энциклопедия

Космические корабли и станции, автоматические КА и методы их проектирования, бортовые комплексы управления, системы и средства жизнеобеспечения, особенности технологии производства ракетно-космических систем

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Мониторинг СМИ

Мониторинг СМИ и социальных сетей. Сканирование интернета, новостных сайтов, специализированных контентных площадок на базе мессенджеров. Гибкие настройки фильтров и первоначальных источников.

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Поддерживает ввод нескольких поисковых фраз (по одной на строку). При поиске обеспечивает поддержку морфологии русского и английского языка
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Применить Всего найдено 1703. Отображено 100.
16-02-2012 дата публикации

Magnetic resonance imaging apparatus and method for displaying running direction of fibrous tissue

Номер: US20120038673A1
Автор: Yoshihiro Iwata
Принадлежит: Hitachi Medical Corp

In order to be able to easily obtain a color FA image in which the same fibrous tissue has the same color display even if images are captured in a state in which the position of an object relative to an MRI apparatus is different, a diffusion tensor is configured using plural sets of the diffusion-weighted image data acquired by capturing images of a site including the fibrous tissue of the object, an eigenvector is obtained from the diffusion tensor, the eigenvector represented by a predetermined first coordinate system is converted into a second coordinate system, and an image representing the running direction of the fibrous tissue is obtained on the basis of the components of the eigenvector represented by the second coordinate system. The second coordinate system is obtained preferably on the basis of the scanned cross-section, or on the basis of the eigenvector for the specified pixel in the image obtained by capturing images of the cross-section, or in accordance with the rotation angle of the coordinate system set by a coordinate system rotation UI.

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Номер записи: 1
01-03-2012 дата публикации

Magnetic resonance device

Номер: US20120049845A1
Автор: Hisaaki Ochi, Koji Hirata, Satoshi Hirata, Toru Shirai, Yoshitaka Bito, Yosuke Otake
Принадлежит: HITACHI LTD

In the diffusion spectroscopic imaging, in which intensity of molecular diffusion is imaged with separating chemical substances, with suppressing artifacts resulting from object motion of an object, spatial resolution, spectral band and SNR are maintained, and measurement accuracy is enhanced. A measurement for acquiring diffusion SI data is repeated a plurality of times with changing acquisition timing, phase variation of each measurement result is corrected, and a diffusion SI image is reconstructed from the corrected measurement results. In addition, the phase variation is calculated for every point in the space from the diffusion SI data acquired by each measurement or navigation data obtained by each measurement. The phase correction is independently performed for every point in the space.

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Номер записи: 2
19-04-2012 дата публикации

Method for a nuclear medicine examination

Номер: US20120095324A1
Автор: Sebastian Schmidt
Принадлежит: SIEMENS AG

A method for a nuclear medicine examination of a patient is disclosed. In at least one embodiment of the method, a magnetic resonance recording of an examination region of the patient is created after a magnetic resonance contrast agent has been administered to the patient. A distribution of the magnetic resonance contrast agent in the examination region is automatically determined from the magnetic resonance recording. After a nuclear medicine tracer has been administered to the patient, a nuclear medicine recording of the examination region of the patient is created. The magnetic resonance contrast agent and the nuclear medicine tracer have essentially identical pharmacokinetic properties. The nuclear medicine recording is corrected as a function of the distribution of the magnetic resonance contrast agent in the examination region.

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Номер записи: 3
10-05-2012 дата публикации

T2-weighted and diffusion-weighted imaging using fast acquisition with double echo (FADE)

Номер: US20120112743A1
Автор: Brian A. Hargreaves, Ernesto Staroswiecki, Kristin L. Granlund
Принадлежит: Leland Stanford Junior University

A method of acquiring T2-weighted and diffusion-weighted images is provided. The method includes acquiring a first image and a second image in a single magnetic resonance imaging (MRI) scan, where the first image and the second image have different echo times (TE). The single MRI scan includes a series of repeated RF excitation pulses, where the echo signal for the first image and the echo signal for the second image are acquired between a pair of RF excitation pulses. A spoiler gradient is disposed to provide a first diffusion weighting to the first image and a second diffusion weighting to the second image, where the first image and the second image have different T2 weightings and different diffusion weightings.

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Номер записи: 4
07-06-2012 дата публикации

Images Of Language-Sensitive Neurocircuitry As A Diagnostic For Autism

Номер: US20120143041A1
Автор: Joy Hirsch
Принадлежит: Columbia University of New York

The disclosed subject matter provides on ore more imaging techniques during passive auditory stimulation to objectively provide a diagnostic indicator of ASD. These techniques include functional MRI (fMRI), diffusion tensor imaging (DTI) and tractography, and combinations thereof. In one embodiment, a method is disclosed that uniquely provides an objective (imaging) physiological technique to diagnose early autism and to monitor progress following therapeutic intervention.

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Номер записи: 5
02-08-2012 дата публикации

System and Method for Diffusion-modulated Relaxation Magnetic Resonance Imaging

Номер: US20120194189A1
Автор: Zhe Phillip Sun
Принадлежит: General Hospital Corp

A system and method for applying an RF excitation pulse to the region of interest (ROI) and a plurality of selective gradients to the ROI to elicit MR data pertaining to at least a first MR parameter from the ROI. The system and method also apply at least one diffusion gradient to the ROI to modulate the first MR parameter with a second MR parameter, acquire MR data from the ROI, and reconstruct a parametric map of the ROI using the MR data, wherein the parametric map is weighted based on the first MR parameter and modulated by the second MR parameter.

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Номер записи: 6
02-08-2012 дата публикации

Diagnosis and treatment of the prodromal schizophrenic state

Номер: US20120195984A1
Автор: Jay L. Lombard
Принадлежит: Genomind Inc

Described herein are compounds (including medical foods, pharmaceutical compositions, methods of compounding them), methods and systems for the diagnosis and/or treatment of prodromal schizophrenia. For example, described herein are methods of treating a developmentally-based neuropsychiatric disorder (schizophrenia) that includes first determining if a subject is at risk for such a disorder by examining phenotypical, serological immune markers and genotypical biomarkers. The biomarkers may be used to tailor the dose to be delivered by the medial food or pharmaceutical composition. Also described are compounds for treating prodromal (rather than full-blown) schizophrenia.

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Номер записи: 7
11-10-2012 дата публикации

Magnetic resonance system and method to generate diffusion information

Номер: US20120259199A1
Автор: David Andrew Porter, Stefan Huwer
Принадлежит: Individual

In a magnetic resonance (MR) method and system for the generation of diffusion information, diffusion-weighted MR images of an examination subject are generated, each image being generated using an individual diffusion gradient. The diffusion gradients, and therefore the MR images, are sorted such that, after the sorting, a predefined number of diffusion gradients respectively forms a group. Each diffusion gradient belongs to at least one of these groups, and the diffusion gradients of the respective same group are all as linearly independent of one another as possible. The MR images whose diffusion gradients form a group are assembled into an MR result image. Spatial transformations between the MR result images are determined, and the MR images are modified using these spatial transformations. The diffusion information is formed with the aid of the modified MR images.

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Номер записи: 8
25-10-2012 дата публикации

Relaxometry quantification self-justification fitting

Номер: US20120268123A1
Автор: Dan Ma, Kecheng Liu, Mark Griswold
Принадлежит: CASE WESTERN RESERVE UNIVERSITY, Siemens Medical Solutions USA Inc

Apparatus, methods, and other embodiments associated with self-justification fitting for magnetic resonance imaging (MRI) relaxation parameter quantification are described. One example nuclear magnetic resonance (NMR) apparatus includes a self-justification fitting logic configured to selectively include and exclude data points from a set of data points associated with NMR signals based, at least in part, on their impact on a fit attribute (e.g., standard deviation). In one embodiment, the self-justification is configured to select a subset of data points from the set of data points as a function of values for a fit attribute computed from fitting at least two different subsets of data points from the set of data points to a known NMR signal evolution.

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Номер записи: 9
25-07-2013 дата публикации

System for Motion Corrected MR Diffusion Imaging

Номер: US20130187649A1
Автор: Andre Jan Willem Van Der Kouwe, Himanshu Bhat, Keith Aaron Heberlein, Matthew Dylan Tisdall
Принадлежит: Siemens Medical Solutions USA Inc

A system determines motion correction data for use in diffusion MR imaging using an RF signal generator and magnetic field gradient generator which sequentially acquire in a single first direction through a volume, first and second slice sets individually comprising multiple individual diffusion image slices. The first set of slices and the second set of slices are spatially interleaved within the volume, by providing in acquiring the second slice set, a low flip angle RF pulse successively followed by a non-diffusion image data readout magnetic field gradient for acquisition of data representing a two dimensional (2D) non-diffusion image used for motion detection of the first slice set successively followed by, a first diffusion imaging RF pulse followed by a first diffusion imaging phase encoding magnetic field gradient for preparation for acquiring data representing a diffusion image slice of the second slice set.

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Номер записи: 10
17-10-2013 дата публикации

Nuclear Magnetic Resonance (NMR) Fingerprinting With Parallel Transmission

Номер: US20130271132A1
Автор: Mark Griswold
Принадлежит: CASE WESTERN RESERVE UNIVERSITY

Apparatus, methods, and other embodiments associated with NMR fingerprinting with parallel transmission are described. One example apparatus includes individually controllable radio frequency (RF) transmission (TX) coils configured to apply varying NMR fingerprinting RF excitations to a sample. The NMR apparatus may apply excitations in parallel. An individual excitation causes different resonant species to produce different signal evolutions. The apparatus includes a parallel transmission logic that causes one of the coils to apply a first excitation to the sample and that causes a different coil to apply a second, different excitation to the sample. The excitations are configured to produce a spatial inhomogeneity between a first region in the sample and a second region in the sample that allows a resonant species to produce a first signal evolution in the first region and to produce a second signal evolution in the second region to facilitate de-correlating the signal evolutions.

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Номер записи: 11
19-12-2013 дата публикации

DIFFUSION TENSOR MAGNETIC RESONANCE IMAGING METHOD

Номер: US20130338486A1
Автор: Huang Yu Qing
Принадлежит:

In a diffusion tensor magnetic resonance imaging method for imaging a myocardial fiber structure, the diaphragm position of a subject is detected and a determination is made as to whether the diaphragm position of the subject falls into the acceptance region or not. If it does not, continue the diaphragm position of the examination subject is continued to be detected. If and when the diaphragm position is in the acceptance region, an echo planar imaging sequence with stimulated echo is executed with two electrocardiogram triggers, so as to acquire diffusion tensor image data of the myocardial fiber structure. The cardiac DTI image data thus can be obtained under free respiration of the subject, and the influence of respiratory movement is reduced and the scanning time is shortened. 1. A diffusion tensor magnetic resonance imaging method for imaging a myocardial fiber structure , comprising:detecting a diaphragm position of a respirating subject and generating diaphragm position information representing the detected diaphragm position;supplying said diaphragm position information to a computerized processor and, in said computerized processor, automatically determining, from the diaphragm position information, whether the diaphragm position of the subject is within an acceptance region and, if not, repeatedly detecting the diaphragm position and determining whether the diaphragm position of the subject is in said acceptance region; andwhen said diaphragm position of the subject is determined to be within said acceptance region, automatically proceeding to operate a magnetic resonance data acquisition unit by implementing an echo planar imaging sequence, with two electrocardiogram triggers, to acquire diffusion tensor image data of a myocardial fiber structure of the subject during stimulated echoes of said echo planar imaging sequence.2. A diffusion tensor magnetic resonance imaging method as claimed in comprising claim 1 , in said processor claim 1 , determining ...

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Номер записи: 12
02-01-2014 дата публикации

Navigator-less segmented diffusion weighted imaging enabled by multiplexed sensitivity-encoded imaging with inherent phase correction

Номер: US20140002078A1
Автор: Allen W. Song, Nan-kuei Chen
Принадлежит: Duke University

Diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) using a new technique, termed multiplexed sensitivity encoding with inherent phase correction, is proposed and implemented to effectively and reliably provide high-resolution segmented DWI and DTI, where shot-to-shot phase variations are inherently corrected, with high quality and SNR yet without relying on reference and navigator echoes. The performance and consistency of the new technique in enabling high-quality DWI and DTI are confirmed experimentally in healthy adult volunteers on 3 Tesla MRI systems. This newly developed technique should be broadly applicable in neuroscience investigations of brain structure and function.

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Номер записи: 13
27-02-2014 дата публикации

Magnetic resonance examination of porous samples

Номер: US20140055134A1
Автор: Edmund J. Fordham, Jonathan Mitchell
Принадлежит: Schlumberger Technology Corp

A method of analysing properties of a porous sample, typically a cylinder of porous rock, comprises centrifuging the sample while it contains at least one liquid, determining the distribution of at least one liquid in the sample by magnetic resonance imaging of the sample, and also determining the distribution of at least one magnetic resonance parameter, where the parameter is one of longitudinal relaxation time T 1 , transverse relaxation time T 2 and diffusion coefficient D. Pore throat sizes can be determined from the distribution of at least one liquid in the sample and pore body sizes can be determined from the distribution of the magnetic resonance parameter enabling determination of a relationship between pore throat sizes and pore body sizes in the sample. This can be a relationship between individual values of pore throat size and an average of body sizes of pores having that individual pore throat size.

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Номер записи: 14
06-01-2022 дата публикации

ORGANOTYPIC DRG-PERIPHERAL NERVE CULTURE SYSTEM

Номер: US20220003742A1
Автор: DEISTER Curt
Принадлежит: AXOGEN CORPORATION

Techniques and systems are disclosed for a bioassay that is an in vitro mimic of peripheral nerve generation using the sensory neurons that innervate the peripheral nervous system. In some embodiments, the techniques may assist in detecting the bioactivity or potency of nerve grafts (e.g., processed, acellular human allografts) for fostering or supporting peripheral nerve regeneration. In various embodiments, techniques comprise affixing a harvested sensory neuron (e.g., a DRG) to a nerve graft segment to form a test construct; culturing the test construct in a medium; analyzing the test construct to indicate the amount of outgrowing peripheral nerve structure; and determining the potency of the nerve graft from a metric derived from the analysis. In some embodiments, techniques and materials may be used to test the effect of a varied test condition on peripheral nerve growth. 1. A method for testing the effect of a condition on nerve outgrowth , the method comprising: submerging the nerve graft in a solution comprising a test compound,', 'dosing the nerve graft with radiation or heat,', 'mechanically modifying the microstructure or macrostructure of the nerve graft,', 'dosing the nerve graft with an outgrowth promoting agent or an outgrowth inhibiting agent,', 'applying an electrical field to the nerve graft, and', 'seeding the nerve graft with stem cells or Schwann cells;, 'treating a nerve graft in accordance with a study protocol, the study protocol comprises one or more ofaffixing a dorsal root ganglion (DRG) to a first end of the nerve graft to form a test construct;culturing the test construct in a medium for a period of time to allow nerve outgrowth from the DRG into the nerve graft; andperforming an analysis of the test construct to determine an amount of an outgrowing nerve structure.2. The method of claim 1 , further comprising comparing one or more analysis metrics derived from the analysis to one or more control metrics determined from nerve grafts not ...

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Номер записи: 15
05-01-2017 дата публикации

System and Method For High Resolution Diffusion Imaging

Номер: US20170003368A1
Автор: Michailovich Oleg, Ning Lipeng, Rathi Yogesh, Setsompop Kawin
Принадлежит:

A system and method for producing high resolution diffusion information and imaging from a subject. In some aspects, the method includes receiving a plurality of low resolution diffusion images, each acquired with a different set of gradient directions and shifted in a slice direction, and generating a model correlating diffusion signals associated with the plurality of low resolution diffusion images and a high resolution diffusion image. The method also includes reconstructing the high resolution diffusion image by minimizing a cost function determined using the model. In some applications, the method further includes processing the high resolution diffusion image to generate a report providing diffusion information associated with the subject. 1. A method for producing high resolution diffusion imaging , the method comprising:receiving a plurality of low resolution diffusion images, each acquired with a different set of gradient directions and shifted in a slice direction;generating a model correlating diffusion signals associated with the plurality of low resolution diffusion images and a high resolution diffusion image; andreconstructing the high resolution diffusion image by minimizing a cost function determined using the model.2. The method of claim 1 , wherein the method further comprises performing an echo planar imaging sequence using a magnetic resonance imaging (“MRI”) system to acquire the low resolution diffusion images.3. The method of claim 1 , wherein each of the plurality of low resolution diffusion images samples at least one portion of q-space.4. The method of claim 3 , wherein the at least one portion of q-space comprises a spherical shell in q-space.5. The method of claim 1 , wherein the plurality of low resolution diffusion images comprise anisotropic voxel sizes.6. The method of claim 1 , wherein the plurality of low resolution diffusion images overlap in the slice direction.7. The method of claim 1 , wherein in the model claim 1 , voxels ...

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Номер записи: 16
27-01-2022 дата публикации

SYSTEMS AND METHODS OF GENERATING ROBUST PHASE IMAGES IN MAGNETIC RESONANCE IMAGES

Номер: US20220026516A1
Автор: BAYRAM ERSIN, GUIDON ARNAUD, Lebel Robert Marc, Litwiller Daniel Vance, Sprenger Tim, Wang Xinzeng
Принадлежит:

A computer-implemented method of correcting phase and reducing noise in magnetic resonance (MR) phase images is provided. The method includes executing a neural network model for analyzing MR images, wherein the neural network model is trained with a pair of pristine images and corrupted images, wherein the corrupted images include corrupted phase information, the pristine images are the corrupted images with the corrupted phase information reduced, and target output images of the neural network model are the pristine images. The method further includes receiving MR images including corrupted phase information, and analyzing the received MR images using the neural network model. The method also includes deriving pristine phase images of the received MR images based on the analysis, wherein the derived pristine phase images include reduced corrupted phase information, compared to the received MR images, and outputting MR images based on the derived pristine phase images. 1. A computer-implemented method of correcting phase and reducing noise in magnetic resonance (MR) phase images , comprising:executing a neural network model for analyzing MR images, wherein the neural network model is trained with a pair of pristine images and corrupted images, wherein the corrupted images include corrupted phase information, the pristine images are the corrupted images with the corrupted phase information reduced, and target output images of the neural network model are the pristine images;receiving MR images including corrupted phase information;analyzing the received MR images using the neural network model;deriving pristine phase images of the received MR images based on the analysis, wherein the derived pristine phase images include reduced corrupted phase information, compared to the received MR images; andoutputting MR images based on the derived pristine phase images.2. The method of claim 1 , wherein the corrupted phase information includes noise in phase images claim 1 , ...

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Номер записи: 17
10-01-2019 дата публикации

METHOD AND APPARATUS FOR OPTIMIZATION OF A TIME PROGRESSION OF A MAGNETIC RESONANCE CONTROL SEQUENCE

Номер: US20190011518A1
Автор: Feiweier Thorsten
Принадлежит: Siemens Healthcare GmbH

In a method and magnetic resonance (MR) apparatus or optimizing a time progression of an MR control sequence that operates an MR scanner of the MR apparatus so as to execute at least two sequence modules, a property of a component of the magnetic resonance apparatus is detected, and a first requirement of the component is determined for a first sequence module of the at least two sequence modules. A second requirement of the component is detected for a second sequence module of the at least two sequence modules. The time progression of the at least two sequence modules is optimized, taking account of the property, the first requirement and second requirement. 1. A method for optimizing a time progression of a magnetic resonance (MR) control sequence , said method comprising:providing a computer with an MR control sequence with which an MR imaging apparatus, comprising an MR scanner and a plurality of apparatus components, is operable in order to acquire MR data from a subject, said MR control sequence comprising at least two sequence modules;providing said computer with an electronic input designating a property of at least one of said components;in said computer, determining a first requirement of said at least one component, associated with use of said at least one component in said MR imaging apparatus when acquiring said MR data from the patient, for a first sequence module of said at least two sequence modules;in said computer, determining a second requirement of said at least one component, associated with use of said at least one component in said MR imaging apparatus when acquiring said MR data from the patient, for a first sequence module of said at least two sequence modules;in said computer, optimizing a time progression of said at least two sequence modules dependent on said property, said first requirement, and said second requirement, and thereby producing an optimized MR control sequence, and generating electronic control signals corresponding to said ...

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Номер записи: 18
03-02-2022 дата публикации

METHOD FOR OPTIMIZED BIAS AND SIGNAL INFERENCE IN MAGNETIC RESONANCE IMAGE ANALYSIS

Номер: US20220034985A1
Автор: KUCZERA Stefan, MAIER Stephan
Принадлежит:

An approach to estimate noise, Rician signal bias and true signal in magnitude signal data obtained with magnetic resonance imaging. The method uses multiple measurements at different scan parameter settings, also referred to as weightings, and an iterative algorithm to estimate noise, expected signal and associated Rician signal bias. Measurements at all measured weighting levels contribute to the ultimate estimation of the bias-free signal decay function. Therefore, of the so processed magnetic resonance image data, weighted signals can be computed at arbitrary weighting levels and with considerably better signal-to-noise ratio than the originally obtained data at corresponding weightings. Bias-free weighted image data at desired weighting levels, maps of the decay function fit parameters, or maps of a combination of such decay function parameters can be used for rapid and highly sensitive tissue characterization. 1. A method for highly reliable non-mono-exponential fitting of diffusion-weighted images , said method comprising the steps of:a) providing a magnetic resonance imaging apparatus capable of operation at diffusion encoding levels (b-factors) within a range ranging at least between an upper and a lower limit;b) acquiring a set of magnitude signal decays from a patient using said magnetic resonance imaging apparatus at each of a selected plurality of encoding levels distributed across the range of b-factors within its capability, each said set of signal decays being representative of an image of a preselected cross-section of the patient, and each said signal decay of each said set corresponding to a pixel of its associated image;c) processing said acquired or bias-corrected signal decays on a pixel by pixel basis to obtain the best possible fit between them and a non-mono-exponential equationwherein a non-linear least-squares method is used to obtain a fit.2. The method of claim 1 , wherein said lower limit is below 500 sec/mm.3. The method of claim 1 , ...

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Номер записи: 19
16-01-2020 дата публикации

“One Stop Shop” for Prostate Cancer Staging using Imaging Biomarkers and Spatially Registered Multi-Parametric MRI

Номер: US20200015734A1
Автор: Mayer Rulon
Принадлежит:

The purpose of this embodiment is to describe a “one stop shop” for staging prostate cancer and a novel application of supervised target detection algorithms to spatially registered multiparametric MRI images in order to non-invasively detect, locate, and score prostate cancer at the voxel level and measure the tumor volume and assign color to the spatially registered MRI to highlight and display tumors, and detect metastases (specifically in the seminal vesicle). To test the approach advanced by the embodiment, a retrospective study analyzes MRI from 26 patients that had also undergone robotic prostatectomy. Whole-mount sections were stained for histopathologic evaluation and matched to the MRI. The stained sections were independently reviewed by pathologists. All slices of various types of MRI were spatially registered and stitched together. Signatures or image-based biomarkers from registered multiparametric MRI training sets were extracted. The untransformed and “whitened-dewhitened” transformed signatures (based on the statistics of the normal prostate) from a battery of Gleason scores were applied to the stitched hypercubes. Each voxel in the supervised target map was polled to find the signature that achieved the highest Gleason score likelihood. The Gleason scoring and volume measurements were quantitatively validated by comparing the results from 10 patients with prostate adenocarcinoma to the pathologist's assessment of the histology. High correlation between supervised target detection using “whitened-dewhitened” transformed signatures and histology was observed (p<0.02). Assigning red, green, and blue to the registered MRI hypercubes effectively displays tumors relative to normal prostate tissue. With only minor modifications, supervised target detection and transformation of target signatures and color display may be used to find metastases, specifically to the seminal vesicles. This novel application of supervised target detection algorithms to ...

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Номер записи: 20
21-01-2016 дата публикации

Fractional Order and Entropy Bio-Markers for Biological Tissue in Diffusion Weighted Magnetic Resonance Imaging

Номер: US20160018504A1
Автор: Ingo Carson, Magin Richard
Принадлежит:

The invention disclosed herein provides an example method and system for characterizing a biological structure in terms of bio-markers derived from DWI data. The methodology includes estimating bio-markers in a fixed diffusion time protocol, estimating bio-markers in fixed diffusion encoding gradient strength protocol, calculating parameters of a model, and using the parameters to characterize a biological structure. Using the techniques and methods described herein, the data may be used to identify structural degeneration, structural integrity and response to therapeutics.

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Номер записи: 21
18-01-2018 дата публикации

PULSE SEQUENCE METHOD FOR MRI

Номер: US20180017648A1
Автор: Lasic Samo, NILSSON Markus, Topgaard Daniel
Принадлежит: CR Development AB

The present invention describes a method for magnetic resonance (MR) and/or MR imaging, comprising acquisition of signals and MR images originating from a RE and gradient sequence causing isotropic diffusion weighting of signal attenuation, wherein the isotropic diffusion weighting is achieved by one time-dependent dephasing vector q(t) having an orientation, wherein the isotropic diffusion weighting is proportional to the trace of a diffusion tensor D, and wherein the orientation of the time-dependent dephasing vector q(t) is either varied discretely in more than three directions in total, or changed continuously, or changed in a combination of discretely and continuously during the gradient pulse sequence, 0≦t≦echo time, where t represents the time. The method may be performed during a single shot (single MR excitation). 19.-. (canceled)10. A method for magnetic resonance (MR) and/or MR imaging , the method comprising:performing a diffusion encoding scheme, the diffusion encoding scheme comprising a radio frequency (RF) and gradient sequence being configured to cause isotropic diffusion weighting of an echo signal attenuation, wherein the RF and gradient sequence has a time-dependent dephasing vector q(t) representation, and wherein the RF and gradient sequence is such that an orientation of the time-dependent dephasing vector q(t) assumes more than three directions in total, andacquiring echo signals resulting from the diffusion encoding scheme.11. A method according to claim 10 , wherein an inclination ζ of the orientation of the time-dependent dephasing vector q(t) is constant during the RF and gradient sequence and equal to a cos(1/√{square root over (3)}).12. A method according to claim 11 , wherein an azimuth angle ψ claim 11 , of the orientation of the time-dependent dephasing vector q(t) is varied during the RF and gradient sequence.13. A method according to claim 12 , wherein the azimuth angle is varied such that the time-dependent dephasing vector q(t) ...

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Номер записи: 22
18-01-2018 дата публикации

METHOD AND MAGNETIC RESONANCE APPARATUS FOR DETERMINING DIFFUSION-WEIGHTED IMAGE DATA

Номер: US20180017650A1
Автор: de Oliveira Andre, Grodzki David
Принадлежит: Siemens Healthcare GmbH

In a method and magnetic resonance (MR) apparatus for determining diffusion-weighted image data, first raw data are acquired with a first diffusion weighting, and the first raw data are assigned to a first k-space matrix. Second raw data are acquired with a second diffusion weighting, and the second raw data are assigned to a second k-space matrix. The first k-space matrix and the second k-space matrix are different from one another at at least one position. The diffusion-weighted image data are determined in a processor based on the first raw data and the second raw data. 1. A method for determining diffusion-weighted image data by magnetic resonance (MR) imaging , said method comprising:operating an MR data acquisition scanner to acquire first raw MR data with a first diffusion weighting, and entering said first raw MR data into an electronic memory organized with a first k-space matrix therein;operating said MR data acquisition scanner to acquire second raw MR data with a second diffusion weighting, and entering said second raw MR data into a second k-space matrix organized in said electronic memory, said first k-space matrix and said second k-space matrix being different from each other at at least one position therein;from a processor, accessing said electronic memory and determining diffusion-weighted image data from said first raw data in said first k-space matrix and said second raw data in said second k-space matrix; andfrom said processor, making the determined diffusion-weighted image data available in electronic form, as a data file.2. A method as claimed in comprising operating said MR data acquisition scanner to acquire said second raw MR data with said second diffusion weighting being stranger than said first diffusion weighting.3. A method as claimed in comprising organizing said electronic memory so that said second k-space matrix is smaller than said first k-space matrix.4. A method as claimed in comprising organizing said electronic memory so that ...

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Номер записи: 23
18-01-2018 дата публикации

SYSTEM AND METHOD FOR CONNECTIVITY MAPPING

Номер: US20180018769A1
Автор: DYER Kelly Noel, KHAN Ali Raza
Принадлежит:

A processing system for and a method of segmenting a physiological image is provided. Once the physiological image is received, extrinsic data defining extrinsic regions is further received. Additionally, intrinsic data defining at least one intrinsic region, each intrinsic region corresponding to one extrinsic region is received. A primary modification is performed, where a shape and size of at least one extrinsic region having a corresponding intrinsic region is modified based on a shape and size of the corresponding intrinsic region, to form a modified extrinsic data. The physiological image is segmented into segmented regions based on the modified extrinsic data, each segmented region which has a corresponding intrinsic region representing a primary modification based on the corresponding intrinsic region. 1. A computer implemented method of segmenting a physiological image comprising:receiving extrinsic data defining extrinsic regions;receiving multiple sets of intrinsic data defining at least one intrinsic region, each intrinsic region corresponding to one extrinsic region and said multiple sets of intrinsic data being obtained from one or more sources; andmodifying a shape and size of at least one extrinsic region having a corresponding intrinsic region based on a shape and size of the corresponding intrinsic region, to form a modified extrinsic data;segmenting the physiological image into segmented regions based on the modified extrinsic data, each segmented region which has a corresponding intrinsic region representing a modification based on the corresponding intrinsic region;receiving intrinsic tract data comprising tracts;receiving waypoint regions;identifying a bundle comprising an identified subset of the tracts; andupdating the modified extrinsic data with tract data indicative of said bundle.2. The method of wherein said one or more sources include fMRI images and EEG data.3. The method of wherein one of said multiple sets of intrinsic data modifies ...

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Номер записи: 24
16-01-2020 дата публикации

PHASE ERROR CORRECTION FOR BIPOLAR READ OUT GRADIENTS

Номер: US20200018809A1
Автор: DUIJNDAM ADRIANUS JOSEPH WILLIBRORDUS
Принадлежит:

The invention provides for a magnetic resonance imaging system () for acquiring preliminary magnetic resonance data () from an imaging zone (). The magnetic resonance imaging system comprises: a memory () for storing machine executable instructions () and preparation pulse sequence commands (). The preparation pulse sequence commands are configured for controlling the magnetic resonance imaging system to acquire the preliminary magnetic resonance data as a first data portion () and a second data portion (). The preparation pulse sequence commands configured for controlling the magnetic resonance imaging system to generate a first bipolar readout gradient during acquisition of the first portion. The preparation pulse sequence commands configured for controlling the magnetic resonance imaging system to generate a second bipolar readout gradient during acquisition of the second portion. The first bipolar readout gradient has an opposite polarity to the second bipolar gradient. The magnetic resonance imaging system further comprises a processor () for controlling the magnetic resonance imaging system. Execution of the machine executable instructions causes the processor to: control () the magnetic resonance imaging system with the preparation pulse sequence commands to acquire the first data portion and the second data portion; calculate () a measured normalised phase correction quantity () in image space using the first data portion and the second data portion; and fit () a modeled phase correction () to the measured phase error, wherein the modeled phase correction is an exponential of a complex value multiplied by a phase error function (), wherein the phase error function is spatially dependent. 1. A magnetic resonance imaging system for acquiring preliminary magnetic resonance data from an imaging zone , wherein the magnetic resonance imaging system comprises:a memory for storing machine executable instructions and preparation pulse sequence commands, wherein the ...

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Номер записи: 25
21-01-2021 дата публикации

A PHANTOM FOR MULTI-PARAMETRIC CALIBRATION IN MAGNETIC RESONANCE IMAGING

Номер: US20210018584A1
Автор: Golay Xavier, Oliver-Taylor Aaron
Принадлежит: GOLD STANDARD PHANTOMS LIMITED

The invention provides a phantom for use in an MRI scanner comprising: an outer housing; a plurality of vessels located within the outer housing, each of the vessels containing a material, wherein the value of a property of the material at a particular temperature is different for each of the vessels; and a phase change material between the outer housing and the vessels. The invention also provides a method for manufacturing a phantom, a method for obtaining calibrated measurements from non-calibrated images using a phantom, a system for obtaining calibrated measurements from non-calibrated images, and a coil assembly for use in an MRI scanner. 1. A phantom for use in an MRI scanner comprising:an outer housing;a plurality of vessels located within the outer housing, each of the vessels containing a material, wherein the value of at least one property of the material at a particular temperature is different for the material contained within each of the vessels; anda phase change material between the outer housing and the vessels.2. A phantom according to claim 1 , wherein at least a part of the outward facing surface of the outer housing is a concave surface.3. A phantom according to claim 2 , wherein the vessels are each fixed at an equal distance from the concave surface.4. A phantom according to any of and claim 2 , wherein the outer housing comprises a convex outward facing surface parallel to the concave surface and the vessels are fixed in place between the convex and concave surfaces.5. A phantom according to claim 4 , wherein the outer housing comprises two flat side faces and the vessels extend between and are coupled to the side faces to hold the vessels in position.6. A phantom according to claim 1 , wherein the outer housing is shaped as a cuboid.7. A phantom according to claim 6 , wherein the outer housing has a maximum dimension of 5 cm to 25 cm claim 6 , such that it can fit and be integrated within RF coils of the scanner.8. A phantom according to ...

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Номер записи: 26
28-01-2016 дата публикации

DETERMINATION OF PHYSIOLOGICAL PARAMETERS OF TISSUE FROM DYNAMIC CONTRAST-ENHANCED MR DATA

Номер: US20160022169A1
Автор: BREEUWER Marcel, Mischi Massimo, WIJKSTRA HESSEL
Принадлежит:

A method of determining microvascular architecture is disclosed. Dynamic contrast-enhanced magnetic resonance data acquired from a contrast agent administered to at least a part of a subject to be examined. From the dynamic contrast-enhanced magnetic resonance data a leakage parameter (k) and a dispersion parameter (κ) are computed. Effects of both convective dispersion and extravasation kinetics of contrast agent are taken into account. 1. A computer implemented method of determining microvascular architecture from dynamic contrast-enhanced magnetic resonance data , acquired by a magnetic resonance imaging system from a contrast agent administered to at least a part of a subject to be examined , the method comprising:{'sub': 'ep', 'from the dynamic contrast-enhanced magnetic resonance data a leakage parameter (k) and a dispersion parameter (κ) are simultaneously computed taking into account effects of both convective dispersion and extravasation kinetics of contrast agent, by fitting a time concentration curve (TCC), that is measured from the magnetic resonance data, to a full dispersion model (FDM) or a reduced dispersion model (RDM) of intravascular and extravascular concentrations, wherein the FDM or RDM is derived from a modified local density random walk model.'}2. (canceled)3. The method of claim 1 , wherein the administered contrast agent's bolus' progression in the part of the subject is approximated by a normal (Gaussian) distribution.4. The method of claim 1 , wherein in the convective dispersion a capillary component is neglected.5. The method of claim 1 , wherein in the extravasation kinetics a monocomponent representation of leakage is employed.6. A computer program comprising executable instructions stored on a non-transitory computer readable storage medium claim 1 , which when executed by a processor causes the processor to perform a method for determining microvascular architecture from dynamic contrast-enhanced magnetic resonance data acquired ...

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Номер записи: 27
22-01-2015 дата публикации

MAGNETIC RESONANCE IMAGING APPARATUS, IMAGE PROCESSING APPARATUS, AND IMAGE PROCESSING METHOD

Номер: US20150022210A1
Автор: Bito Yoshitaka, Ochi Hisaaki, Yokosawa Suguru
Принадлежит:

The present invention provides a technique for obtaining a high-quality image at high speed in DKI analysis. In the DKI analysis, upon estimating a parameter relating to diffusion in an application direction of an MPG pulse, a least square fitting is separated from a constraint processing, and only a value of the pixel that does not meet the constraint condition in the least square fitting is targeted for the correction. Then, with regard to this pixel, a diffusion-related parameter is re-estimated using the pixel value after the correction, and a parameter image is generated by using the diffusion-related parameter thus obtained. 1. A magnetic resonance imaging apparatus comprising ,an imager configured to perform measurement according to a pulse sequence being predetermined, and reconstruct an image, andan image processor configured to subject the image being reconstructed to an arithmetic processing, and obtain a parameter image,the pulse sequence being a diffusion weighted imaging sequence that applies an MPG (motion probing gradient) pulse, the MPG pulse being configured to add signal variation along with diffusion as a gradient magnetic field to a nuclear magnetic resonance signal, wherein,the imager executes the pulse sequence with varying an application direction and a b-value of the MPG pulse so as to acquire plural images, andthe image processor comprises,an ROI setter configured to set a region of interest on the image,a parameter estimator configured to estimate a diffusion parameter being a diffusion-related parameter with respect to each pixel, by using a value of the pixel in the region of interest of the plural images obtained by executing the pulse sequence, setting the application direction of the MPG pulse to be identical and varying the b-value,a discriminator configured to make a determination whether or not the diffusion parameter being estimated is within a predetermined range,a pixel value corrector configured to perform correction on the ...

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Номер записи: 28
25-01-2018 дата публикации

TISSUE-ORIENTATION-BASED SIMULATION OF DEEP BRAIN STIMULATION

Номер: US20180020974A1
Автор: Varkuti Bálint
Принадлежит:

The present invention relates to a medical data processing method for determining an orientation of nerve fibres relative to a non-physiological electric field, the method comprising the following steps which are constituted to be executed by a computer: a) acquiring patient medical image data describing a patient medical image of an anatomical body part of a patient's body, the anatomical body part including nerve tissue comprising white matter nerve fibres; b) acquiring diffusion image data describing a diffusion-enhanced image of the anatomical body part; c) acquiring atlas data describing a spatial distribution of grey value-based tissue classes in a model body part representing a model of the anatomical body part; d) determining, based on the patient image data and the diffusion image data and the atlas data, fibre orientation data describing an orientation of the white matter nerve fibres; e) acquiring electric field orientation data describing an orientation of the non-physiological electric field which is an electric field simulated around a simulated electrode virtually placed in a predetermined spatial relationship relative to the anatomical body part; f) determining, based on the fibre orientation data and the electric field orientation data, relative orientation data describing a relative orientation between the orientation of the white matter nerve fibres and the orientation of the electric field. 115.-. (canceled)16. A medical visualization system for determining an orientation of nerve fibers relative to a non-physiological electric field , comprising:a display device; and acquire, at the processor, patient medical image data describing a patient medical image of an anatomical body part of a body of an associated patient, the anatomical body part including nerve tissue comprising white matter nerve fibers;', 'acquire, at the processor, diffusion image data describing a diffusion-enhanced image of the anatomical body part;', 'acquire, at the processor, ...

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Номер записи: 29
26-01-2017 дата публикации

Scan condition determining apparatus and method for a magnetic resonance imaging system

Номер: US20170023657A1
Автор: Masanori Ozaki, Yoshihiro Tomoda
Принадлежит: GE Medical Systems Global Technology Co LLC, General Electric Co

There is provided a scan condition determining apparatus for a magnetic resonance imaging system comprising accepting means for accepting specification of a desired scan time; and searching means for searching for a second scan condition based on a first scan condition defined before the specification, by adjusting values of parameters affecting a scan time or a signal-to-noise ratio of signals obtained by a scan, said second scan condition being one with which the scan time approximates within an allowable range or matches the desired scan time, and besides, a lowest value of a relative signal-to-noise ratio of the signals approximates within an allowable range or matches a lowest value of the relative signal-to-noise ratio of the signals estimated based on the first scan condition. The parameters include, for example, any one of a number of times of addition, a y-axis direction resolution, a repetition time, and a number of data acquisition passes.

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Номер записи: 30
26-01-2017 дата публикации

SYSTEM AND METHOD FOR CORRECTING INTRINSIC HETEROGENEITY IN MAGNETIC RESONANCE IMAGING

Номер: US20170023658A1
Автор: Sun Phillip Zhe
Принадлежит:

A system and method acquiring images of a region of interest (ROI) of a subject using a magnetic resonance imaging system. The system or method are capable of acquiring pathological data from tissue in the ROI believed to be pathological tissue and acquiring baseline data from tissue in the subject believed to not be pathological tissue. The system or method are also capable of determining correlation parameters from baseline data, generating corrected data using the baseline correlation parameters to correct the pathological data at least for intrinsic heterogeneity, and generating a report using the corrected data. 1. A magnetic resonance imaging (MRI) system comprising:a magnet system configured to generate a polarizing magnetic field about at least a region of interest (ROI) of a subject arranged in the MRI system, the ROI including tissue believed to be pathological tissue;a plurality of gradient coils configured to apply a gradient field with respect to the polarizing magnetic field;a radio frequency (RF) system configured to apply RF excitation fields to the subject and a acquire MR image data therefrom; and i) control the plurality of gradient coils and the RF system to acquire diffusion kurtosis imaging (DKI) data from the ROI;', 'ii) determine baseline correlation parameters from baseline MR data;', 'iii) generate relaxation-normalized kurtosis data using the baseline correlation parameters to correct the DKI data at least for relaxation variations affecting kurtosis in the DKI data;', 'iv) generate a report using the relaxation-normalized kurtosis data., 'a computer programmed to2. The system of wherein the baseline correlation parameters include at least one of mean diffusivity (MD) claim 1 , fractional anisotropy (FA) claim 1 , and relaxation rates (R1 claim 1 , R2).3. The system of wherein the computer is further programmed to control the plurality of gradient coils and the RF system to acquire the baseline MR data from the subject at an ROI believed ...

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Номер записи: 31
24-01-2019 дата публикации

MRI Pulse Sequence Design

Номер: US20190025392A1
Автор: Chen Xiao, Mailhe Boris, Nadar Mariappan S., Odry Benjamin L.
Принадлежит:

A method uses an artificial neural network (ANN) to automatically produce a magnetic resonance (MR) pulse sequence. A first MR signal corresponding to a first tissue and a second MR signal corresponding to a second tissue are identified. An RF pulse to be applied to the first and second tissues is selected. Based on at least the first MR signal, the second MR signal, and the RF pulse, an updated first MR signal and an updated second MR signal are determined. A difference is computed between the updated first MR signal and the updated second MR signal. The difference is added to an accumulated difference. The RF pulse selecting, updated first and second MR signal determination, difference computation and adding are repeated. The ANN is controlled to use reinforcement learning to select the MR imaging pulse sequence based, at least in part, on the accumulated difference. 1. A method for using an artificial neural network (ANN) to automatically produce a magnetic resonance (MR) imaging pulse sequence , the method comprising:(a) identifying a first MR signal corresponding to a first tissue and a second MR signal corresponding to a second tissue,(b) selecting an RF pulse to be applied to the first tissue and the second tissue;(c) based on at least the first MR signal, the second MR signal, and the RF pulse determining an updated first MR signal and an updated second MR signal;(d) computing a difference between the updated first signal and the updated second MR signal;(e) adding the difference to an accumulated difference;(f) repeating steps (b) to (e) one or more times;(g) controlling the ANN to use reinforcement learning to select the MR imaging pulse sequence based, at least in part, on the accumulated difference.2. The method of claim 1 , wherein step (c) includes using a Bloch simulator to compute the updated first MR signal and the updated second MR signal.3. The method of claim 1 , wherein step (g) selects the MR imaging pulse sequence so as to maximize the ...

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Номер записи: 32
31-01-2019 дата публикации

METHOD FOR DETERMINING ISCHEMIC STATUS OR ASSESSING STROKE ONSET TIME OF A BRAIN REGION

Номер: US20190029557A1
Автор: CHEN Cheng-Yu, CHUNG Hsiao-Wen, KAO Yu-Chieh Jill, KUO Duen-Pang, LU Chia-Feng
Принадлежит:

The invention relates to a method for determining ischemic status. The method comprises acquiring magnetic resonance diffusion tensor matrices and obtaining a relative decrease of diffusion magnitude due to the ischemic status from the magnetic resonance diffusion tensor matrices. The invention also relates to a method for assessing stroke onset time. The method comprises acquiring magnetic resonance diffusion tensor matrices and obtaining a relative decrease of pure anisotropy due to stroke from the magnetic resonance diffusion tensor matrices. 1. A method for determining ischemic status of a brain region , comprising:acquiring magnetic resonance diffusion tensor matrices of the brain region and of a normal brain tissue, wherein the normal brain tissue and the brain region belong to the same brain tissue type;{'sub': i', 'n, 'obtaining diffusion magnitude (L) of the brain region (L) and diffusion magnitude of the normal brain tissue (L) from the magnetic resonance diffusion tensor matrices; and'}{'sub': i', 'n', 'i', 'n, 'calculating a relative decrease of Lto L, and the ischemic status is determined by the relative decrease of Lto L.'}2. The method according to claim 1 , which further comprises acquiring a brain tissue type map claim 1 , wherein the brain tissue type map is obtained by fractional anisotropy (FA) mapping calculated from the magnetic resonance diffusion tensor matrices.3. The method according to claim 1 , wherein the brain region and the normal brain tissue belong to the same brain tissue type in an atlas-based tissue classification method.4. The method according to claim 1 , wherein the normal brain tissue is a contralateral homologous tissue of the brain region.5. A method for establishing an index of given ischemic status claim 1 , comprising:{'claim-ref': {'@idref': 'CLM-00001', 'claim 1'}, 'sub': i', 'n', 'i', 'n, 'determining ischemic status of a brain region having the given ischemic status according to the method as claimed in for obtaining ...

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Номер записи: 33
02-02-2017 дата публикации

SELECTIVE SAMPLING FOR ASSESSING STRUCTURAL SPATIAL FREQUENCIES WITH SPECIFIC CONTRAST MECHANISMS

Номер: US20170030986A1
Автор: James Kristin M., James Timothy W.
Принадлежит:

The disclosed embodiments provide a method for acquiring MR data at resolutions down to tens of microns for application in in-vivo diagnosis and monitoring of pathology for which changes in fine tissue textures can be used as markers of disease onset and progression. Bone diseases, tumors, neurologic diseases, and diseases involving fibrotic growth and/or destruction are all target pathologies. Further the technique can be used in any biologic or physical system for which very high-resolution characterization of fine scale morphology is needed. The method provides rapid acquisition of selected values in k-space, with multiple successive acquisitions of individual k-values taken on a time scale on the order of microseconds, within a defined tissue volume, and subsequent combination of the multiple measurements in such a way as to maximize SNR. The reduced acquisition volume, and acquisition of only select values in k-space along selected directions, enables much higher in-vivo resolution than is obtainable with current MRI techniques. 1. A method for selective sampling to assess tissue texture using magnetic resonance (MR) comprising:applying a contrast mechanism enhancing the contrast between the component tissue types in a multiphase biologic sample being measured;selectively exciting a volume of interest (VOI) employing a plurality of time varying radio frequency signals and applied gradients;applying an encoding gradient pulse to induce phase wrap to create a spatial encode for a specific k-value and orientation, the specific k-value determined based on texture within the VOI;initiating a time varying series of gradients to produce a time varying trajectory through 3D k-space of k-value encodes, a resulting k-value set being a subset of that required to produce an image of the VOI;simultaneously recording multiple sequential samples of the NMR RF signal encoded with the k-value set;post processing the recorded NMR signal samples to produce a data set of signal vs ...

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Номер записи: 34
01-02-2018 дата публикации

DETECTING NERVE DAMAGE USING DIFFUSION TENSOR IMAGING

Номер: US20180031663A1
Автор: Becerra Lino, Borra Ronald, BORSOOK David, Serrano Paul
Принадлежит:

A method includes: identifying, by a processing circuit, diffusion tensor imaging (DTI) data of a peripheral nerve in a subject that is associated with an area of pain experienced by the subject; determining, by the processing circuit, one or more DTI-derived measurements from the DTI data for each of one or more nerve branches of the peripheral nerve; and detecting, by the processing circuit, potential nerve damage in a particular nerve branch of the one or more nerve branches based on the one or more DTI-derived measurements associated with the particular nerve branch. 1. A method comprising:identifying, by a processing circuit, diffusion tensor imaging (DTI) data of a peripheral nerve in a subject that is associated with an area of pain experienced by the subject;determining, by the processing circuit, one or more DTI-derived measurements from the DTI data for each of one or more nerve branches of the peripheral nerve; anddetecting, by the processing circuit, potential nerve damage in a particular nerve branch of the one or more nerve branches based on the one or more DTI-derived measurements associated with the particular nerve branch.2. The method of claim 1 , further comprising:identifying, by the processing circuit, a first and second nerve branch of the peripheral nerve based on the DTI data,wherein the particular nerve branch corresponds to the first nerve branch or the second nerve branch.3. The method of claim 2 , wherein the peripheral nerve includes a sciatic nerve of the subject claim 2 , the first nerve branch includes a tibial nerve of the subject claim 2 , and the second nerve branch includes a fibular nerve of the subject.4. The method of claim 3 , wherein DTI data acquisition is centered around a region that is approximately 10 to 15 centimeters above an upper rim of a patella of the subject.5. The method of claim 1 , wherein the peripheral nerve includes a femoral nerve of the subject.6. The method of claim 1 , wherein the one or more DTI-derived ...

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Номер записи: 35
01-02-2018 дата публикации

DETERMINING DIFFUSION TENSORS USING MAGNETIC RESONANCE TOMOGRAPHY SCANNERS

Номер: US20180031664A1
Автор: Speier Peter
Принадлежит:

A magnetic resonance tomography scanner is provided for the determination a diffusion tensor of an examination object, and a method is provided for operating the magnetic resonance tomography scanner. The magnetic resonance tomography scanner acquires a volume image of the examination object by imaging magnetic resonance tomography without diffusion encoding. The control system segments the image according to diffusion-relevant symmetry properties and also determines volume elements of a symmetry group. A first and a second component of a diffusion tensor are acquired by the magnetic resonance tomography scanner at different angles and the control unit uses the symmetry property with the acquired components and the volume image to determine a diffusion tensor for the volume elements. 1. A method for determining a diffusion tensor of an examination object by a magnetic resonance tomography scanner , the method comprising:acquiring a volume image of the examination object by imaging magnetic resonance tomography without diffusion encoding;segmenting the volume image and determining a diffusion-relevant first symmetry property of the examination object in a plane of symmetry;determining a first symmetry group of volume elements of the examination object with the first symmetry property;acquiring a first image of a first component of the diffusion tensor in a first direction at a first angle to the plane of symmetry;acquiring a second image of a second component of the diffusion tensor in a second direction at a second angle to the plane of symmetry, wherein a magnitude of the second angle differs from a magnitude of the first angle; anddetermining the diffusion tensor of a first volume element of the first symmetry group, wherein the first components of the diffusion tensor obtained in the first image and the second components of the diffusion tensor obtained in the second image from a plurality of second volume elements of the first symmetry group are mapped onto the ...

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Номер записи: 36
31-01-2019 дата публикации

System and Method for Optimized Diffusion - Weighted Imaging

Номер: US20190033410A1
Автор: Aliotta Eric, Ennis Daniel B., Wu Holden H.
Принадлежит:

A system and method for optimized diffusion-weighted imaging is provided. In one aspect, the method includes providing a plurality of constraints for imaging a target at a selected diffusion weighting, and applying an optimization framework to generate an optimized diffusion encoding gradient waveform satisfying the plurality of constraints. The method also includes performing, using the MRI system, a pulse sequence comprising the optimized diffusion encoding gradient waveform to generate diffusion-weighted data, and generating at least one image of the target using the diffusion-weighted data. 1. A method for generating images using a magnetic resonance imaging (“MRI”) system , the method comprising:a) providing a plurality of constraints for imaging a target at a selected diffusion weighting;b) applying an optimization framework to generate an optimized diffusion encoding gradient waveform satisfying the plurality of constraints;c) performing, using the Mill system, a pulse sequence comprising the optimized diffusion encoding gradient waveform to generate diffusion-weighted data; andd) generating at least one image of the target using the diffusion-weighted data.2. The method of claim 1 , wherein the plurality of constraints comprises at least one of at least one of gradient constraints claim 1 , gradient moment constraints claim 1 , and hardware constraints.3. The method of claim 2 , wherein the gradient constraints comprise zero gradient values during a radiofrequency (“RF”) activity and a readout.4. The method of claim 2 , wherein the gradient moment constraints comprise at least one of a zero moment (“M0”) claim 2 , a first moment (“M1”) claim 2 , a second moment (“M2”) claim 2 , a third moment (“M3”) and a fourth moment (“M4”) is nulled.5. The method of claim 1 , wherein applying the optimization framework at step b) further comprises performing an iterative process to minimize at least one of timing parameters comprising a gradient duration during a ...

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Номер записи: 37
09-02-2017 дата публикации

AUTOMATIC TRACT EXTRACTION VIA ATLAS BASED ADAPTIVE CONNECTIVITY-BASED CLUSTERING

Номер: US20170035320A1
Автор: Tunc Birkan, Verma Ragini
Принадлежит:

Method and apparatus for processing diffusion data for identification of white matter tracts in the brain of a patient is provided herein. The method involves, with a processor: generating a connectivity based representation of white matter fibers for multiple different subjects from the connectivity signatures of the fibers from a diffusion magnetic resonance imaging (dMRI) without using the physical coordinates of the fibers; generating a fiber bundle atlas from the connectivity based fiber representation of (a) which define a model of the human brain; adaptively clustering fibers of a new patient utilizing the fiber bundle atlas of (b) to extract white matter tracts without manual intervention in the form of drawing regions of interest; and presenting the selected white matter tracts and diffusion data in a report or on a display device. This method and apparatus can be used even for patients having edema or brain perturbations. 1. A method for processing diffusion data for identification of white matter tracts in the brain of a patient , said method comprising , with a processor:(a) generating a connectivity based representation of white matter fibers for multiple different subjects from the connectivity signatures of the fibers from a diffusion magnetic resonance imaging (dMRI) without using the physical coordinates of the fibers;(b) generating a fiber bundle atlas from the connectivity based fiber representation of (a) which define a model of the human brain;(c) adaptively clustering fibers of a new patient utilizing the fiber bundle atlas of (b) to extract white matter tracts; and(d) presenting the selected white matter tracts and diffusion data in a report or on a display device.2. The method according to claim 1 , wherein (a) further comprises constructing a connectivity based fiber representation by (i) defining a parcellation of the brain of each of the multiple different subjects into regions by mapping an anatomic atlas including these regions to each ...

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Номер записи: 38
24-02-2022 дата публикации

EPI MR IMAGING WITH DISTORTION CORRECTION

Номер: US20220057467A1
Автор: VALVANO GIUSEPPE
Принадлежит:

The invention relates to a method of MR imaging of an object () positioned in an examination volume of a MR device (). An object of the invention is to provide a method that enables EPI imaging with improved distortion correction. The method of the invention comprises the steps of: acquiring reference MR signal data from the object () using a multi-point Dixon method; deriving a Bmap from the reference MR signal data; acquiring a series of imaging MR signal data sets from the object (), wherein an instance of an echo planar imaging sequence is used for acquisition of each imaging MR signal data set; and reconstructing an MR image from each imaging MR signal data set, wherein geometric distortions in each MR image are corrected using the Bmap. Moreover, the invention relates to a MR device () for carrying out the method, and to a computer program to be run on a MR device (). 1. A method of magnetic resonance (MR) imaging of an object positioned in an examination volume of a MR device , the method comprising:acquiring reference MR signal data from the object using a multi-point Dixon method;{'sub': '0', '#text': 'deriving a Bmap from the reference MR signal data;'}acquiring a series of imaging MR signal data sets from the object, wherein an instance of an echo planar imaging sequence is used for acquisition of each imaging MR signal data set, and{'sub': '0', '#text': "reconstructing a dynamic series of MR images from the imaging MR signal data sets, wherein one of the imaging MR signal data sets is acquired with a direction of the echo planar imaging's phase-encoding gradient blips which is opposite to the direction of the phase-encoding gradient blips used in the acquisition of the other imaging MR signal data sets and said MR signal data set(s) is acquired with said opposite phase-encoding gradient provides prior knowledge that is included in correction using the Bmap of geometric distortions in each MR image."}2. The method of claim 1 , wherein the imaging MR ...

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Номер записи: 39
06-02-2020 дата публикации

LOW-FIELD DIFFUSION WEIGHTED IMAGING

Номер: US20200041588A1
Автор: "OHalloran Rafael", Sacolick Laura
Принадлежит: Hyperfine Research, Inc.

Methods and apparatus for operating a low-field magnetic resonance imaging (MRI) system to perform diffusion weighted imaging, the low-field MRI system including a plurality of magnetics components including a Bmagnet configured to produce a low-field main magnetic field B, at least one gradient coil configured to, when operated, provide spatial encoding of emitted magnetic resonance signals, and at least one radio frequency (RF) component configured to acquire, when operated, the emitted magnetic resonance signals. The method comprises controlling one or more of the plurality of magnetics components in accordance with at least one pulse sequence having a diffusion-weighted gradient encoding period followed by multiple echo periods during which magnetic resonance signals are produced and detected, wherein at least two of the multiple echo periods correspond to respective encoded echoes having an opposite gradient polarity. 1. A low-field magnetic resonance imaging (MRI) system , comprising: [{'sub': 0', '0, 'a Bmagnet configured to produce a low-field main magnetic field B;'}, 'at least one gradient coil configured to, when operated, provide spatial encoding of emitted magnetic resonance signals;', 'at least one radio frequency (RF) component configured to acquire, when operated, the emitted magnetic resonance signals; and, 'a plurality of magnetics components includingat least one controller configured to operate one or more of the plurality of magnetics components in accordance with at least one pulse sequence having a diffusion-weighted gradient encoding period followed by multiple echo periods during which magnetic resonance signals are produced and detected, wherein at least two of the multiple echo periods correspond to respective encoded echoes having an opposite gradient polarity.2. The low-field MRI system of claim 1 , wherein the at least one controller is further configured to reconstruct at least one image based claim 1 , at claim 1 , least in part claim ...

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Номер записи: 40
06-02-2020 дата публикации

MAGNETIC RESONANCE IMAGING APPARATUS AND MAGNETIC RESONANCE IMAGING METHOD

Номер: US20200041600A1
Автор: ICHINOSE NOBUYASU, IMAMURA Naho, KASSAI YOSHIMORI, Nitta Shuhei, OHMURE Takahiro, Takai Hiroshi
Принадлежит: Canon Medical Systems Corporation

According to one embodiment, a magnetic resonance imaging apparatus includes processing circuitry. The processing circuitry calculates a static magnetic field correction amount based on a static magnetic field distribution of a first imaging range narrower than a second imaging range. The processing circuitry collects a magnetic resonance (MR) image of the second imaging range under a static magnetic field which is corrected based on the static magnetic field correction amount. The processing circuitry corrects distortion of the collected the MR image. 1. A magnetic resonance imaging apparatus comprising processing circuitry configured to:calculate a static magnetic field correction amount based on a static magnetic field distribution of a first imaging range narrower than a second imaging range;collect a magnetic resonance (MR) image of the second imaging range under a static magnetic field which is corrected based on the static magnetic field correction amount; andcorrect distortion of the collected the MR image.2. The apparatus according to claim 1 , whereinthe processing circuitry calculates the static magnetic field correction amount so that a first-order differential of a static magnetic field intensity of the first imaging range becomes positive.3. The apparatus according to claim 1 , whereinthe processing circuitry calculates the static magnetic field correction amount so that distortion of the MR image takes the form of extension of pixels.4. The apparatus according to claim 1 , whereinthe processing circuitry is further configured to display a shift amount of a pixel position of the MR image.5. The apparatus according to claim 4 , whereinthe processing circuitry displays the shift amount in the form of a vector.6. The apparatus according to claim 4 , whereinthe processing circuitry displays the shift amount in the form of grid.7. The apparatus according to claim 1 , whereinthe MR image is a diffusion-weighted image taken with the use of an echo planar ...

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Номер записи: 41
18-02-2021 дата публикации

METHOD AND SYSTEM FOR DIFFUSION MAGNETIC RESONANCE IMAGING

Номер: US20210048499A1
Автор: Li Guobin, LI Zhaopeng, Liu Nan
Принадлежит: SHANGHAI UNITED IMAGING HEALTHCARE CO., LTD.

A method may include obtaining a plurality of groups of imaging data. Each group of the plurality of groups of imaging data may be generated based on MR signals acquired by an MR scanner via scanning a subject using a diffusion sequence. The method may also include determining one or more correction coefficients associated with an error caused by the diffusion sequence for each group of the plurality of groups of imaging data. The method may also include determining, based on the one or more correction coefficients corresponding to the each group of the plurality of groups of imaging data, a plurality of groups of corrected imaging data. The method may further include determining averaged imaging data by averaging the plurality of groups of corrected imaging data in a complex domain and generating, based on the averaged imaging data, an MR image. 1. A system for magnetic resonance imaging (MRI) , comprising:at least one storage device storing executable instructions, and obtaining a plurality of groups of imaging data, each group of the plurality of groups of imaging data being generated based on MR signals acquired by an MR scanner via scanning a subject using a diffusion sequence;', 'for each group of the plurality of groups of imaging data, determining one or more correction coefficients associated with an error caused by the diffusion sequence;', 'determining, based on the one or more correction coefficients corresponding to the each group of the plurality of groups of imaging data, a plurality of groups of corrected imaging data;', 'determining averaged imaging data by averaging the plurality of groups of corrected imaging data in a complex domain; and', 'generating, based on the averaged imaging data, an MR image., 'at least one processor in communication with the at least one storage device, when executing the executable instructions, causing the system to perform operations including2. The system of claim 1 , wherein the one or more correction coefficients ...

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Номер записи: 42
18-02-2016 дата публикации

Correcting for Main Magnetic Field Inhomogeneity in MRI Scanners

Номер: US20160047876A1
Автор: Alhamud Alqadafi Ali, Meintjes Ernesta Maria, Van Der Kouwe Andre Jan Willem
Принадлежит:

A method for correcting for main magnetic field (B) inhomogeneity in a Magnetic Resonance Imaging (MRI) scanner is disclosed. The method includes applying a first and a second three-dimensional volumetric navigator after an acquisition of a volume in a scanning sequence and before the next volume is acquired. From a resultant pair of navigator images, a magnetic field map is obtained by complex division of the pair of navigator images, and the field map is used to determine parameters to adjust the MRI scanner to compensate for B inhomogeneity. The navigators may excite only a portion of an entire object to be imaged, so that adjustment of the MR scanner can be done slice-by-slice or slab-by-slab. Motion correction can also be implemented by comparing the first navigator to a stored reference image and updating for motion before acquisition of the next volume in the scanning sequence. 10. A method of correcting for main magnetic field (B) inhomogeneity in a Magnetic Resonance Imaging (MRI) scanner during a scanning sequence which includes the acquisition of successive volumes by means of Magnetic Resonance (MR) pulse sequences , comprising: applying a first three-dimensional volumetric navigator and obtaining a first navigator image,', 'applying a second three-dimensional volumetric navigator after the first navigator and obtaining a second navigator image, wherein the first and second navigators have different echo times;, 'after an acquisition of a volume in the scanning sequence determining a magnetic field map by complex division of the first and second navigator images;', {'b': '0', 'using the magnetic field map to determine parameters required to adjust the homogeneity of the main magnetic field (B); and'}, 'adjusting the MRI scanner based on the determined parameters., 'after the first and second navigator images have been obtained and before the acquisition of the next volume in the scanning sequence2. The method as claimed in claim 1 , wherein the ...

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Номер записи: 43
16-02-2017 дата публикации

METHODS AND SYSTEMS FOR GENERATING A CONDUCTIVITY MAP OF AN IN VIVO TISSUE

Номер: US20170045601A1
Автор: AKHTARI MASSOUD
Принадлежит:

The present disclosure provides methods of generating a conductivity map of an in vivo tissue. The present disclosure provides systems for generating a conductivity map of an in vivo tissue. 1. A non-invasive method of generating a conductivity map of an in vivo tissue , the method comprising:a) measuring a concentration of a carrier ion in the tissue using magnetic resonance imaging (MRI);b) measuring a water proton diffusivity (D) in the tissue using diffusion tensor MRI (DT-MRI); and {'br': None, 'i': D n q', 'kT, 'sup': '2', 'σ=()/'}, 'c) generating a conductivity map of the tissue, using the formulawherein σ is conductivity, D is the water proton diffusivity, n is the concentration of the carrier ion, q is a charge of the carrier ion, k is Boltzmann constant, and T is temperature in degrees Kelvin.2. The method of claim 1 , wherein the tissue is brain tissue.3. The method of claim 1 , wherein the tissue is heart tissue.4. The method of claim 1 , wherein the concentration of the carrier ion and the water proton diffusivity are measured using a single coil.5. The method of claim 1 , wherein the carrier ion is selected from a sodium ion claim 1 , a chloride ion claim 1 , a potassium ion claim 1 , and a calcium ion.6. The method of claim 1 , wherein the DT-MRI is performed at 0.3 T.7. The method of claim 1 , wherein the DT-MRI is performed at 1.5 T.8. The method of claim 1 , wherein the DT-MRI is performed at 3 T.9. The method of claim 1 , wherein the DT-MRI is performed at 7 T.10. The method of claim 1 , wherein the DT-MRI is performed at 9 T.11. The method of claim 1 , wherein the DT-MRI is performed at 12 T.12. A system for generating a conductivity map of an in vivo tissue claim 1 , the system comprising:a) a magnetic resonance imaging (MRI) device configured to measure a concentration of a carrier ion in the tissue and a water proton diffusivity (D) in the tissue;b) a processor; and {'br': None, 'i': D n q', 'kT, 'sup': '2', 'σ=()/'}, 'c) a non-transient ...

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Номер записи: 44
15-02-2018 дата публикации

MRI METHOD FOR DETERMINING SIGNATURE INDICES OF AN OBSERVED TISSUE FROM SIGNAL PATTERNS OBTAINED BY MOTION-PROBING PULSED GRADIENT MRI

Номер: US20180045802A1
Автор: LE BIHAN Denis
Принадлежит:

A method for determining a signature index of an observed tissue comprises the step of providing a generic attenuation model of a motion-probing gradient pulse MRI attenuated signal S(b), and providing a reference model parameter vector (p(i)) corresponding to a reference state of the tissue. On the basis of the evolution of the determined partial differential sensitivities dS(b) of the model attenuated signal S(b) to each model parameter p(i) at the neutral state attenuated signal S(b) versus values, a discrete and narrow size set of key is built and a series of MRI images of the observed tissue are acquired by using the key b values. Then, for each voxel a signature index (sADC(V), Sdist(V), SCdist(V), Snl(V), SI(V)) of the voxel V is determined as a scalar function depending on a distance between the voxel signal pattern acquired at the key values and the signal pattern of the reference state of the tissue at the same key values. An apparatus is configured for implementing such a method. 1. A method for determining one or several signature indices of an observed tissue , representative sensitively of a type of tissue or representative sensitively of a microstructure or biological state of a type of tissue , the signature indices being determined from motion-probing pulses gradient Magnetic Resonance Images (MRI) of the observed tissue , and the method comprising the steps of:providing a generic attenuation model of a diffusion MRI attenuated signal S(b), representative of the type of the tissue to be observed, suited to Intra Voxel Incoherent Motion (IVIM) and/or non-Gaussian signal patterns, and expressed by a model function f(b), depending on a gradient attenuation factor b and on a first set of model parameters p(i) characterizing when valued the type of tissue and the microstructure state, said model parameters p(i) defining a model parameter vector space and NP being the number of model parameters of the first set;{'sub': R', 'R, 'providing a reference model ...

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Номер записи: 45
22-02-2018 дата публикации

METHODS AND SYSTEMS OF EVALUATING AXONAL LOSS AND DEMYELINATION

Номер: US20180049665A1
Автор: BISSON ERICA, JEONG EUN-KEE (E.K.), JEONG KYLE, LEE YOUJUNG, Rose John W., SAPKOTA NABRAJ, SHAH LUBDHA, THAPA BIJAYA
Принадлежит:

Disclosed are methods and systems for obtaining ultra-high b radial diffusion-weighted imaging signals from a selected portion of a nervous system of a subject and comparing at least two ultra-high b radial diffusion-weighted imaging signals for the selected portion of the nervous system of the subject. The comparison is indicative of changes in the integrity or intactness of a bundle of axons within the selected portion of the nervous system of the subject. 2. The method of claim 1 , wherein the b-value diffusion-weighting gradient is greater than 4 claim 1 ,000 s/mmto suppress water signals from the extra-axonal space.3. The method of claim 1 , wherein the selected portion of the nervous system of the subject comprises a selected portion of a spinal cord of the subject.4. The method of claim 1 , wherein the selected portion of the nervous system of the subject comprises a selected portion of a brain of the subject.5. The method of claim 1 , wherein the selected portion of the nervous system of the subject comprises an optic nerve of the subject.6. The method of claim 1 , wherein the subject is a patient having multiple sclerosis.7. The method of claim 3 , wherein the subject is a patient having a condition selected from the group consisting of: cervical spondylotic myelopathy (CSM) claim 3 , motor-neuron diseases including amyotrophic lateral sclerosis (ALS) claim 3 , metabolic vitamin B12 deficiency affecting spinal cord claim 3 , transverse myelitis claim 3 , transverse myelopathy claim 3 , neuro myelitis optica claim 3 , and combinations thereof.8. The method of claim 1 , wherein using the at least one processing unit to compare the at least two ultra-high b radial diffusion-weighted imaging signals comprises:(a) for each radial diffusion-weighted imaging signal, determining a fraction of restricted water within the restricted region; and(b) comparing the determined fractions of restricted water for the at least two radial diffusion-weighted imaging signals.9. ...

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Номер записи: 46
25-02-2016 дата публикации

COMPENSATED MAGNETIC RESONANCE IMAGING SYSTEM AND METHOD FOR IMPROVED MAGNETIC RESONANCE IMAGING AND DIFFUSION IMAGING

Номер: US20160054420A1
Автор: WONG Alexander Sheung Lai
Принадлежит:

There is disclosed a novel system and method for improving MRI and DWI image quality and tissue detail and contrast is introduced and referred to in this disclosure as “compensated magnetic resonance imaging” or CMRI in which a compensation function and noise scale factor are determined during a calibration process by acquiring one or more test signals on the MRI system to determine a compensation function and noise scale factor, and signal acquisitions are conducted from a subject, and the signals are then used to reconstruct MRI images by maximizing a quality metric that takes the acquired signals, compensation function, and noise scale factor as part of the input parameters. Advantageously, by taking into a compensation function and a noise scale factor, CMRI can provide significantly improved MRI image quality and tissue detail and contrast. 1. A method operable on a processing device , having a processor and a memory , tier obtaining a magnetic resonance imaging (MRI) image from a MRI system , comprising:acquiring one or more test signals from a MRI system utilizing a test phantom object with known dimensions and characteristics;determining a compensation function that minimizes an error metric that takes a baseline calibration signal from the MRI system and the one or more acquired test signals transformed by the compensation function;determining a noise scale factor based on the plurality of acquired test signals by computing noise statistics in homogeneous areas where true signal intensities are substantially uniform in the one or more test signals; andutilizing the acquired test signals, the calculated compensation function, and the noise scale factor as input parameters to calculate an image quality metric.2. The method of claim 1 , further comprising:acquiring a signal from a subject using an MRI system;reconstructing an MRI image of the MRI subject by maximizing the image quality metric; anddisplaying the reconstructed MRI image on a display.3. The ...

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Номер записи: 47
23-02-2017 дата публикации

Tractography Framework With Magnetic Resonance Imaging For Brain Connectivity Analysis

Номер: US20170052241A1
Автор: Cetingul Hasan Ertan, Odry Benjamin L.
Принадлежит:

In white matter tractography from magnetic resonance imaging, a mathematical representation of diffusion (e.g., fiber orientation distributions) is first estimated from the diffusion MR data. Fiber tracing is performed via deterministic or probabilistic tractography where the tract maps and brain regions from multiple atlases and/or templates can be used for seeding and/or as spatial constraints. Field map correction and/or denoising may improve the diffusion weighted imaging data used in tractography. 1. A method for tractography with magnetic resonance imaging , the method comprising:scanning a patient with a magnetic resonance imaging system for diffusion weighted data, the scanning providing data without diffusion sensitization and in phase-encoded and reverse phase encoded directions, the diffusion weighted data being in a subject space;acquiring, with the magnetic resonance imaging system, structural magnetic resonance data;correcting the diffusion weighted data with field maps estimated from the data acquired in the phase encoding and reverse phase encoding directions;denoising the corrected diffusion weighted data;registering a first atlas of tract maps to the subject space;identifying regions of interest through which tracts of the tract maps pass from a second atlas;generating a tractogram for the patient from the denoised, corrected diffusion weighted data, the tract maps, and the regions of interest; andtransmitting an image of the tractogram.2. The method of wherein scanning comprises performing diffusion magnetic resonance imaging.3. The method of wherein correcting comprises field map correcting.4. The method of wherein denoising comprises performing local principle component analysis.5. The method of wherein registering comprises registering the tract maps as probabilistic maps of fiber tracts.6. The method of wherein registering comprises determining first fractional anisotropy data from a fit of diffusion tensors to the denoised claim 1 , corrected ...

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Номер записи: 48
01-03-2018 дата публикации

QUANTITATIVE DIFFERENTIATION OF INFLAMMATION FROM SOLID TUMORS, HEART AND NERVE INJURY

Номер: US20180055408A1
Автор: Lin Tsen-Hsuan, Song Sheng-Kwei, Spees William, Ye Zezhong
Принадлежит:

D-Histo, a non-invasive diagnostic method, renovated from diffusion basis spectrum imaging (DBSI) is provided for quantitatively detecting and distinguishing inflammation from solid tumors, heart and nerve injury. For example, the D-Histo methods disclosed herein provide an accurate diagnosis of prostate cancer, distinguishing it from prostatitis and BPH that missed by currently available methods of diagnosing prostate cancer (multiparameter MRI, needle biopsy). The disclosed D-Histo method also provides metrics to reflect reversible vs. irreversible damages in heart and central/peripheral nerves. For central and peripheral nerves, D-Histo also provides metrics to assess nerve functionality. The at least one D-Histo biomarker obtained using diffusion weighted MRI has excellent test-retest stability, high sensitivity to disease progression and close correlation with currently available techniques. 1. A method of classifying microstructures in a tissue volume , the method comprising:taking an MRI image of the tissue volume by an MRI scanner;determining diffusion tensor components of water molecules within a voxel derived from the MRI image via a processor coupled to the MRI scanner;determining apparent diffusion coefficients of the water molecules with diffusion tensor components falling in a predetermined range associated with a microstructure via the processor; andidentifying the microstructure in the voxel derived from the MRI image based on classified diffusion tensor components where the apparent diffusion coefficients fall in the predetermined range via the processor.2. The method of claim 1 , wherein the microstructure is a cancerous microstructure.3. The method of claim 1 , wherein the microstructure is a non-cancerous microstructure.4. The method of claim 1 , further comprising generating an image map of the tissue volume from the voxel showing a presence of the microstructure on an electronic display.5. The method of claim 1 , wherein determining the ...

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Номер записи: 49
10-03-2022 дата публикации

SYSTEMS AND METHODS FOR PROVIDING OPERATING POWER TO AN MAGNETIC RESONANCE IMAGING (MRI) SYSTEM

Номер: US20220075015A1
Автор: Twieg Michael
Принадлежит: Hyperfine, Inc.

Systems and methods for operating a magnetic resonance imaging (MRI) system are provided. The MRI system includes a magnetics system and a power system configured to provide power to at least some of the magnetics system. The power system includes an energy storage device and a power supply configured to receive mains electricity. The MRI system also includes at least one controller configured to control the MRI system to operate in accordance with a pulse sequence at least in part by generating, by using power supplied by the power supply and supplemental power supplied by the energy storage device, at least one gradient field using at least one gradient coil of the magnetics system. 1. A magnetic resonance imaging (MRI) system configured to operate in accordance with a pulse sequence having multiple periods , the MRI system comprising:{'claim-text': [{'sub': '0', '#text': 'a Bmagnet; and'}, 'a gradient coil;'], '#text': 'a magnetics system comprising:'}{'claim-text': ['an energy storage device; and', 'a power supply configured to receive mains electricity; and'], '#text': 'a power system configured to provide power to at least one component of the magnetics system, the power system comprising:'}{'claim-text': 'generating, by using power supplied by the power supply and supplemental power supplied by the energy storage device, a gradient field using the gradient coil.', '#text': 'a controller configured to control the MRI system to operate in accordance with the pulse sequence at least in part by:'}2. The MRI system of claim 1 , wherein the energy storage device is coupled to the MRI system using a bidirectional DC-to-DC power converter.3. The MRI system of claim 2 , wherein the bidirectional DC-to-DC power converter comprises a synchronous buck DC-to-DC power converter claim 2 , a synchronous boost DC-to-DC power converter claim 2 , or a four switch buck-boost DC-to-DC power converter.4. The MRI system of claim 1 , wherein the power supply is further configured to ...

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Номер записи: 50
03-03-2016 дата публикации

SHEET TRACTOGRAPHY USING DIFFUSION TENSOR MRI

Номер: US20160061923A1
Автор: MEKKAOUI Choukri
Принадлежит:

Systems and methods are provided for performing sheet tractography using diffusion tensor magnetic resonance imaging (“MRI”), Diffusion tensor data acquired from a subject using an MR] system is provided. Eigenvectors and eigenvalues are determined for locations within a subject from the data. Fiber sheets are produced based on these eigenvectors and eigenvalues. For instance, at each location, a fiber sheet is defined to extend along a direction of a first eigenvector, and to have a width that extends along a direction defined by a second eigenvector and a thickness that extends along a direction defined by a third eigenvector. The width and thickness of a fiber sheet can be scaled based on the eigenvalues associated with the second and third eigenvectors, respectively. Metrics, such as a torsion angle that defines the twisting of a fiber sheet, can be determined and mapped based on the fiber sheets. 1. A method for performing tractography using magnetic resonance imaging (“MRI”) , the steps of the method comprising:a) providing diffusion tensor imaging (“DTI”) data acquired from a subject using a MRI system;b) determining from the DTI data, a set of eigenvectors for each of a plurality of different locations within a region in the subject, each set of eigenvectors corresponding to a location in the region and comprising a first eigenvector oriented along a first direction, a second eigenvector oriented along a second direction, and third eigenvector oriented along a third direction;c) producing a fiber sheet based on the sets of eigenvectors, the fiber sheet being defined at each location to extend along the first direction and to have a width extending along the second direction and a thickness extending along the third direction; andd) generating, using the fiber sheet, a tractography map representative of a tissue architecture of a subject.2. The method of claim 1 , wherein step b) includes computing a diffusion tensor at each of the plurality of different ...

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Номер записи: 51
02-03-2017 дата публикации

APPARATUS AND METHOD FOR CONTROLLING PULSE SEQUENCE OF MAGNETIC RESONANCE IMAGING SYSTEM

Номер: US20170059681A1
Автор: Lai Yongchuan, Mao Xiaoxi, Wei Moran
Принадлежит:

The present invention provides an apparatus and method for controlling a pulse sequence of a magnetic resonance (MR) imaging system, the MR imaging system comprising a radio frequency magnetic field coil and a gradient magnetic field coil, the apparatus for controlling a pulse sequence of the MR imaging system comprising a radio frequency driving unit and a gradient driving unit. The gradient driving unit is used for applying a first motion probing gradient (MPG) pulse and a second MPG pulse to the gradient magnetic field coil successively. The radio frequency driving unit is used for applying a radio frequency excitation pulse to the radio frequency magnetic field coil before the first MPG pulse is applied, and for applying a first 90-degree radio frequency refocusing pulse, a 180-degree radio frequency refocusing pulse and a second 90-degree radio frequency refocusing pulse to the radio frequency magnetic field coil successively between a time when the first MPG pulse is applied and a time when the second MPG pulse is applied. 1. An apparatus for controlling a pulse sequence of a magnetic resonance (MR) imaging system , the MR imaging system comprising a radio frequency magnetic field coil and a gradient magnetic field coil , the apparatus for controlling a pulse sequence of the MR imaging system comprising a radio frequency driving unit and a gradient driving unit;the gradient driving unit being used for applying a first motion probing gradient (MPG) pulse and a second MPG pulse to the gradient magnetic field coil successively; andthe radio frequency driving unit being used for applying a radio frequency excitation pulse to the radio frequency magnetic field coil before the first MPG pulse is applied, and for applying a first 90-degree radio frequency refocusing pulse, a 180-degree radio frequency refocusing pulse and a second 90-degree radio frequency refocusing pulse to the radio frequency magnetic field coil successively between a time when the first MPG pulse ...

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Номер записи: 52
11-03-2021 дата публикации

MAGNETIC RESONANCE IMAGING SYSTEM AND METHODS FOR USE WITH A MEDICAL ROBOTIC SYSTEM

Номер: US20210068701A1
Автор: Lee Diana, Panther Alexander Gyles, Piron Cameron Anthony, VUONG Thanh Vinh
Принадлежит:

A magnetic resonance imaging (MRI) system and methods for use with a medical, e.g., a surgical, robotic system, involving an MRI apparatus configured to operate with the surgical robotic system, the MRI apparatus having at least one low-field magnet, the at least one low-field magnet configured to generate a low magnetic field, and the low magnetic field comprising a magnetic flux density in a range of approximately Tesla (T) to approximately T, whereby a standoff between the MRI apparatus and the surgical robotic system is reduced. 1. A magnetic resonance imaging (MRI) system for use with a surgical robotic system , the MRI system comprising:an MRI apparatus configured to operate with the surgical robotic system, the MRI apparatus comprising at least one low-field magnet, the at least one low-field magnet configured to generate a low magnetic field, and the low magnetic field comprising a magnetic flux density in a range of approximately 0.1 T to approximately 0.5 T,whereby a standoff between the MRI apparatus and the surgical robotic system is reduced.2. The MRI system of claim 1 , wherein the MRI apparatus is configured to operate with the surgical robotic system comprising an interventional robotic apparatus.3. The MRI system of claim 1 , wherein the MRI apparatus is configured to operate with the surgical robotic system comprising a robotic apparatus having at least one of a C-arm and a fluoro-table.4. The MRI system of claim 1 , wherein the MRI apparatus is configured to operate with the surgical robotic system comprising a robotic apparatus having at least one of a metallic robotic device and a metallic robotic tool if the MRI system operates outside the range of magnetic flux density for the low magnetic field.5. The MRI system of claim 1 , wherein the MRI apparatus is portable and disposable adjacent the surgical robot in a surgical environment.6. The MRI system of claim 1 , wherein the MRI apparatus comprises a footprint in an area range of approximately ...

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Номер записи: 53
28-02-2019 дата публикации

Image processing apparatus, magnetic resonance imaging apparatus, and image generating method

Номер: US20190064300A1
Автор: Kazuo AWAI, Toru Higaki
Принадлежит: Canon Medical Systems Corp

An image processing apparatus according to an embodiment includes processing circuitry. The processing circuitry obtains a first Magnetic Resonance (MR) image corresponding to a first b-factor and corresponding to each of a plurality of axial directions and to obtain a second MR image corresponding to a second b-factor different from the first b-factor and corresponding to each of the plurality of axial directions. The processing circuitry obtains through a calculation, with respect to each of the axial directions, an MR image as a computed image corresponding to a third b-factor different from the first b-factor and the second b-factor by using the first MR image and the second MR image. The processing circuitry generates a combined image by combining together the plurality of computed images each of which was obtained with respect to a different one of the axial directions.

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Номер записи: 54
29-05-2014 дата публикации

Standardized geometric and physiologic space for visual and quantitative evaluation of tumor mri characteristics

Номер: US20140146048A1
Автор: Bartholomew Patrick Keogh, Xu Feng
Принадлежит: Individual

A system and method for displaying MRI parameters measured from a tissue sample such a tumor. A computer system receives MRI data and determines a number of parameters including, a normalized cerebral blood volume (nCBV), a contrast transfer rate constant (kTrans) and apparent diffusion coefficient (ADC) calculated from Bo and B1000 MRI images for data points in the MRI data. These parameters are plotted onto a three-dimensional graph of voxels where the data in the MRI are mapped to a normalized radial distance and angle in the plot. The parameters nCBV, kTrans and 1/ADC are mapped to a color of the voxel and to height of a voxel in the +Z and −Z axes of the three dimensional plot.

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Номер записи: 55
09-03-2017 дата публикации

IMAGE PROCESSING APPARATUS, MAGNETIC RESONANCE IMAGING APPARATUS, IMAGE PROCESSING METHOD, AND STORAGE MEDIUM

Номер: US20170067978A1
Автор: IIMA Mami, LE BIHAN Denis, YANO KOJIRO
Принадлежит:

Conventionally, it has been impossible to output an image that allows for an easy and accurate diagnosis as to whether or not a malignant tumor is present and that allows for correctly indicating a part with a high or low grade of malignancy in the tumor. With an image processing apparatus that includes: a receiving unit configured to receive diffusion weighted images; a parameter acquisition unit configured to acquire parameters of two or more types for each of one or more units of processing that constitute the diffusion weighted images, by using the diffusion weighted images; a diagnostic image composition unit configured to acquire, for each of the one or more units of processing, a score that corresponds to the parameters of two or more types, by using the parameters of two or more types, and to compose a diagnostic image that is an image having, for each of the one or more units of processing, a pixel value that corresponds to the acquired score that corresponds to the unit of processing; and an output unit configured to output the diagnostic image, it is possible to output an image that allows for an easy and accurate diagnosis as to whether or not a malignant tumor is present and that allows for correctly indicating a part with a high or low grade of malignancy in the tumor. 114-. (canceled)15. An image processing apparatus comprising:a score acquisition management information storage unit in which two or more pieces of score acquisition management information are stored, the score acquisition management information being information in which type information that is information that indicates types of parameter maps, and score acquisition information that is information used for acquiring scores that correspond to parameters that the parameter maps have, are associated with each other;a receiving unit configured to receive diffusion weighted images;a parameter acquisition unit configured to acquire parameters of two or more types for each of two or more ...

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Номер записи: 56
16-03-2017 дата публикации

Magnetic resonance imaging apparatus and image processing apparatus

Номер: US20170071497A1
Автор: Hitoshi Yamagata, Masao Yui
Принадлежит: Toshiba Medical Systems Corp

A magnetic resonance imaging apparatus according to an embodiment includes processing circuitry. The processing circuitry is configured to perform control to display a matrix representing inter-regional connectivity between a plurality of regions in a brain. The processing circuitry is configured to perform, based on an attention degree set to each of the regions, control to selectively display part of a plurality of regions arranged along a first axis of the matrix.

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Номер записи: 57
18-03-2021 дата публикации

SYSTEM, METHOD AND COMPUTER-ACCESSIBLE MEDIUM FOR FACILITATING NOISE REMOVAL IN MAGNETIC RESONANCE IMAGING

Номер: US20210076972A1
Автор: BAETE Steven H., FIEREMANS ELS, LEMBERSKIY GREGORY, NOVIKOV DMITRY, VERAART Jelle
Принадлежит:

An exemplary system, method and computer-accessible medium for generating a denoised magnetic resonance (MR) image(s) of a portion(s) of a patient(s) can be provided, which can include, for example, generating a plurality of MR images of the portion(s), where a number of the MR images can be based on a number of MR coils in a MR apparatus used to generate the MR images, generating MR imaging information by denoising a first one of the MR images based on another one of the MR images, and generating the denoised MR image(s) based on the MR imaging information. The number of the MR coils can be a subset of a total number of the MR coils in the MR apparatus. The number of the MR coils can be a total number of the MR coils in the MR apparatus. The MR information can be generated by denoising each of the MR images based on the other one of the MR images. 1. A non-transitory computer-accessible medium having stored thereon computer-executable instructions for generating at least one denoised magnetic resonance (MR) image of at least one portion of at least one patient , wherein , when a computer arrangement executes the instructions , the computer arrangement is configured to perform procedures comprising:generating a plurality of MR images of the at least one portion, wherein a number of the MR images is based on a number of MR coils in a MR apparatus used to generate the MR images;generating MR imaging information by denoising a first one of the MR images based on at least one other of the MR images; andgenerating the at least one denoised MR image based on the MR imaging information wherein the computer arrangement is configured to generate the MR imaging information using a phase unwinding procedure, and wherein the phase unwinding procedure includes a joint redundancy in at least one phase and at least one measurement over all the MR coils.2. The computer-accessible medium of claim 1 , wherein the number of the MR coils is a subset of a total number of the MR coils in ...

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Номер записи: 58
07-03-2019 дата публикации

METHOD AND MAGNETIC RESONANCE APPARATUS TO ACQUIRE TRACE-WEIGHTED MAGNETIC RESONANCE DATA WITH ANISOTROPIC DIFFUSION DIRECTIONS

Номер: US20190072630A1
Автор: Feiweier Thorsten
Принадлежит: Siements Healthcare GmbH

In a method and a magnetic resonance (MR) apparatus for diffusion-gradient MR imaging, vectors for the diffusion gradients are determined by generating a cuboid with edges that represent the maximum amplitudes that are achievable by the gradient system of the MR apparatus, and a spherical shell is also generated that represents limit values for effective gradient amplitudes. Areas of the spherical shell that are within the cuboid are used as end points of origin vectors that originate from the origin of the intersecting axes of the gradient system. Diffusion gradient vectors that are to be used for acquiring the diffusion-weighted MR data are then selected from these origin vectors dependent on fulfillment of a condition for producing a trace-weighted image with low artifacts. 1. A method for operating a magnetic resonance (MR) scanner in order to acquire diffusion-weighted MR data with anisotropic diffusion directions from an examination region of a subject , so as to produce a trace-weighted image of said examination region from said diffusion-weighted MR data , said MR scanner comprising a gradient system having a gradient coil arrangement defined by physical gradient axes that intersect each other at an origin , said method comprising:in a computer, executing an algorithm that defines a space of diffusion-gradient vectors that are achievable by said gradient system, as a cuboid having edges oriented along said physical gradient axes, with an extent of said edges corresponding to a maximum gradient amplitude that is achievable by said gradient system along said physical gradient axes;in said computer in said algorithm, selecting a value interval for an effective gradient amplitude that defines a minimum value and a maximum value of said effective gradient amplitude;in said computer in said algorithm, establishing a spherical shell around said origin, said spherical shell having an inner radius equal to said minimum value and an outer radius equal to said maximum ...

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Номер записи: 59
05-06-2014 дата публикации

Method for identifying neuroprotective compounds and/or neuroregeneration stimulators by fractional anisotropy measurements by diffusion-based mri scanning

Номер: US20140155731A1
Автор: Damien Galanaud, Habib Benali, Louis Puybasset, Stephane Lehericy, Vincent Perlbarg
Принадлежит: Assistance Publique Hopitaux de Paris APHP

The present invention relates to a method for monitoring the effectiveness of a treatment on neuroprotection and to a method for identifying candidate molecules that are neuroprotectors and/or neuronal growth stimulators. The present invention can be used, in particular, in the field of pharmaceutics, in the field of scientific research and in the field of clinical trials and validation of therapeutic substances.

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Номер записи: 60
05-03-2020 дата публикации

METHOD AND SYSTEM FOR OPERATING A MAGNETIC RESONANCE FACILITY

Номер: US20200072934A1
Автор: Hoelscher Uvo, Koehler Michael, Niederloehner Daniel, Stemmer Alto
Принадлежит: Siemens Healthcare GmbH

In a method for operating a magnetic resonance (MR) facility during recording of MR data by using a MR sequence including a saturation module for a spin type to be saturated, in which a high-frequency saturation pulse is emitted between first and second spoiler gradient pulses, and multiple further gradient pulses apart from the spoiler gradient pulses, eddy current data is determined. The eddy current data describes eddy currents existing during emission of the saturation pulse and resulting from the further gradient pulses. Further, a pulse parameter of the first spoiler gradient pulse is selected based on the eddy current data such that the eddy currents generated by the first spoiler gradient pulse compensate for at least part of the eddy currents described by the eddy current data during emission of the saturation pulse. The facility is controlled to emit the first spoiler gradient pulse with the selected pulse parameter. 1. A method for operating a magnetic resonance (MR) scanner during recording of magnetic resonance data by using a magnetic resonance sequence , which includes at least one saturation module for a spin type to be saturated , in which a high-frequency saturation pulse is emitted between a first and a second spoiler gradient pulse , and multiple further gradient pulses apart from the spoiler gradient pulses , the method comprising:determining eddy current data corresponding to eddy currents which exist during emission of the saturation pulse and resulting from the further gradient pulses;selecting at least one pulse parameter of the first spoiler gradient pulse based on the eddy current data such that the eddy currents generated by way of the first spoiler gradient pulse compensate for at least part of the eddy currents identified in the eddy current data at least during emission of the saturation pulse; andcontrolling the MR scanner to emit the first spoiler gradient pulse with the at least one selected pulse parameter.2. The method as claimed ...

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Номер записи: 61
26-03-2015 дата публикации

Method and magnetic resonance system for acquiring magnetic resonance data

Номер: US20150084629A1
Автор: David Andrew Porter
Принадлежит: SIEMENS AG

In a method for acquiring magnetic resonance data with a magnetic resonance system using a magnetic resonance sequence, the sequence has a first partial sequence in which magnetic resonance data are acquired for multiple slices that have to be acquired simultaneously, from which image data for the individual slices are calculated by a reconstruction algorithm. The sequence also has a second partial sequence for determining additional data, which are used to evaluate and/or assess the magnetic resonance data, and which have a spatial resolution that is lower than the magnetic resonance data, in which radio-frequency pulses and readout processes take place in a slice-specific manner through a time offset within a single measuring process, in which a single continuous excitation period with the radio-frequency pulses and a single continuous readout period with the readout processes follow one another, so that separate additional data are directly determined for each slice.

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Номер записи: 62
31-03-2022 дата публикации

METHOD FOR DETERMINING ISCHEMIC STATUS OR ASSESSING STROKE ONSET TIME OF A BRAIN REGION

Номер: US20220095945A1
Автор: CHEN Cheng-Yu, CHUNG Hsiao-Wen, KAO Yu-Chieh Jill, KUO Duen-Pang, LU Chia-Feng
Принадлежит:

The invention relates to a method for determining ischemic status. The method comprises acquiring magnetic resonance diffusion tensor matrices and obtaining a relative decrease of diffusion magnitude due to the ischemic status from the magnetic resonance diffusion tensor matrices. The invention also relates to a method for assessing stroke onset time. The method comprises acquiring magnetic resonance diffusion tensor matrices and obtaining a relative decrease of pure anisotropy due to stroke from the magnetic resonance diffusion tensor matrices. 1. A method for assessing stroke onset time of a brain region , comprising:acquiring magnetic resonance diffusion tensor matrices of the brain region and of a normal brain tissue, wherein the normal brain tissue and the brain region belong to the same brain tissue type;{'sub': ['i', 'n'], '#text': 'obtaining pure anisotropy (q) of the brain region (q) and pure anisotropy of the normal brain tissue (q) from the magnetic resonance diffusion tensor matrices; and'}{'sub': ['i', 'n', 'i', 'n'], '#text': 'calculating a relative decrease of qto q, and the assessing stroke onset time is determined by the relative decrease of qto q;'}wherein ischemic status of stroke is infarct core.2. The method according to claim 1 , which further comprises acquiring a brain tissue type map claim 1 , wherein the brain tissue type map is obtained by fractional anisotropy mapping calculated from the magnetic resonance diffusion tensor matrices.3. The method according to claim 1 , wherein the brain region and the normal brain tissue belong to the same brain tissue type in an atlas-based tissue classification method.4. The method according to claim 1 , wherein the normal brain tissue is a contralateral homologous tissue of the brain region.5. A method for establishing an index of assessing stroke onset time claim 1 , comprising:providing a plurality of brain regions having a plurality of given stroke onset time; wherein the plurality of brain regions ...

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Номер записи: 63
22-03-2018 дата публикации

Sparse Recovery Of Fiber Orientations Using Multidimensional Prony Method

Номер: US20180081018A1
Автор: Cetingul Hasan Ertan, Mailhe Boris, Nadar Mariappan S., Schwab Evan
Принадлежит:

A computer-implemented method for sparse recovery of fiber orientations using a multidimensional Prony method for use in tractography applications includes performing magnetic resonance imaging to acquire a plurality of sparse signal measurements using a q-space sampling scheme which enforces a lattice structure with a predetermined number of collinear samples. Next, for each voxel included in the plurality of sparse signal measurements, a computer system is used to perform a parameter estimation process. This process includes translating a portion of the sparse signal measurements corresponding to the voxel into a plurality of Sparse Approximate Prony Method (SAPM) input parameters, and applying a SAPM process to the SAPM input parameters to recover a number of fiber populations, a plurality of orientation vectors, and a plurality of amplitude scalars. Then, one or more tractograms are generated using the number of fiber populations, the orientation vectors, and the amplitude scalars recovered for each voxel. 1. A computer-implemented method for sparse recovery of fiber orientations using a multidimensional Prony method for use in tractography applications , the method comprising:performing magnetic resonance imaging to acquire a plurality of sparse signal measurements using a q-space sampling scheme which enforces a lattice structure with a predetermined number of collinear samples; translating a portion of the sparse signal measurements corresponding to the voxel into a plurality of Sparse Approximate Prony Method (SAPM) input parameters, and', 'applying a SAPM process to the SAPM input parameters to recover a number of fiber populations, a plurality of orientation vectors, and a plurality of amplitude scalars; and, 'for each voxel included in the plurality of sparse signal measurements, using a computer system to perform a parameter estimation process comprisinggenerating one or more tractograms using the number of fiber populations, the plurality of orientation ...

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Номер записи: 64
14-03-2019 дата публикации

FREE-BREATHING 3D BODY DIFFUSION IMAGING USING MOTION-COMPENSATED DIFFUSION PREPARATION AND MOTION ROBUST READOUT

Номер: US20190079155A1
Автор: Bi Xiaoming, Fan Zhaoyang, Laub Gerhard, Li Debiao, Natsuaki Yutaka, Nguyen Christopher T.
Принадлежит:

Embodiments can provide a computer-implemented method for free breathing three dimensional diffusion imaging, the method comprising initiating, via a k-space component processor, diffusion/T2 preparation, comprising generating diffusion contrast; and adjusting one or more of amplitude, duration, and polarity to set a first order moment; applying, via an image data processor, a stack of stars k-space ordering, comprising acquiring a radial/spiral view for all members of a plurality of partitions in a partition-encoding direction; increasing an azimuthal angle until a complete set of radial/spiral views are sampled; and applying diffusion gradients along each of three axis simultaneously; and calculating, via the image data processor, an apparent diffusion coefficient map. 1. A computer-implemented method for free breathing three dimensional diffusion imaging , the method comprising: generating diffusion contrast; and', 'adjusting one or more of amplitude, duration, and polarity to set a first order moment;, 'initiating, via a k-space component processor, diffusion/T2 preparation, comprising acquiring a radial/spiral view for all members of a plurality of partitions in a partition-encoding direction;', 'increasing an azimuthal angle until a complete set of radial/spiral views are sampled; and', 'applying diffusion gradients along each of three axis simultaneously; and, 'applying, via an image data processor, a motion robust, non-Cartesian k-space ordering, comprisingcalculating, via the image data processor, an apparent diffusion coefficient map.2. The method as recited in claim 1 , further comprising:generating, via the k-space component processor, diffusion contrast through adding diffusion-sensitizing gradients to a T2-preparation module encompassing hard pulse excitation and adiabatic pulse refocusing.3. The method as recited in claim 1 , further comprising:combining, via the image data processor, along with the stack of stars k-space ordering, one or more of a ...

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Номер записи: 65
24-03-2016 дата публикации

METHOD AND APPARATUS TO CORRECT NOISE EFFECTS IN QUANTITATIVE TECHNIQUES IN MAGNETIC RESONANCE IMAGING

Номер: US20160084929A1
Автор: Dale Brian, Kannengiesser Stephan, Kiefer Berthold, Nickel Marcel Dominik, Zhong Xiaodong
Принадлежит:

In a method to correct noise effects in magnetic resonance (MR) images, which is executed in a processor (computer), the processor executes a fitting algorithm in order to calculate initial values for each of selected variables in signal model that models noise effects in a modeled, noise-containing MR image. The processor then iteratively executes the same or a different fitting algorithm, in order to generate final values for each of the selected variables. The processor is provided with an actual, acquired MR image that contains noise, and the processor uses the final values of the selected variables to calculate synthetic signal intensities in the MR image, thereby producing a synthetic MR image with no noise bias effects of errors. This synthetic image is made available in electronic form at an output of the processor, as a data file. 1. A method to correct noise effects in parameter fitting using magnetic resonance (MR) images , comprising:in a processor, executing a fitting algorithm to calculate initial values for each of selected variables in a signal model that models noise effects in a modeled, noise-containing MR image;in said processor, executing an iterative fitting algorithm, that is the same or a different fitting algorithm, to generate final values for each of said selected variables;providing said processor with an actual MR image that contains noise and, in said processor, using said final values of said selected variables to correct effects of said noise in said actual MR image, thereby producing a parameter mapping image with no noise bias effects or errors, an image corresponding to an initial condition, and further calculating a synthetic MR image with no noise bias effects or errors; andmaking the parameter mapping image with no noise bias effects or errors, the image corresponding to the initial condition, and the synthetic MR image with no noise bias effects or errors available in electronic form at an output of said processor, as ...

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Номер записи: 66
31-03-2022 дата публикации

STORAGE, DISPLAY, AND ANALYSIS OF FACTORED MULTIDIMENSIONAL IMAGES

Номер: US20220099775A1
Автор: Christodoulou Anthony, Li Debiao, Xie Yibin
Принадлежит:

A method of analyzing a multidimensional image tensor containing a plurality of images comprises: performing imaging scans of a subject imaging data; generating the multidimensional image tensor from the imaging data; determining a spatial basis tensor containing basis images based on the multidimensional image tensor; determining a temporal basis tensor containing basis functions for a temporal dimension based on the multidimensional image tensor; determining a core tensor that relates the spatial basis tensor to the temporal basis tensor; pre-multiplying the core tensor and the temporal basis tensor to produce a modified temporal basis tensor; storing the spatial basis tensor and the modified temporal basis tensor; and generating an image by multiplying at least (i) at least a portion of the spatial basis tensor and (ii) at least a portion of the modified temporal basis tensor. 1. A method of analyzing a plurality of images of a region of interest of a subject , the method comprising:performing one or more imaging scans on the region of interest of the subject to obtain imaging data;determining, based on the imaging data, a spatial basis tensor containing one or more basis images;determining, based on the imaging data, one or more temporal basis tensors, each temporal basis tensor containing one or more basis functions for a respective one of a plurality of temporal dimensions;determining, based on the imaging data, a core tensor that relates the spatial basis tensor to each of the one or more temporal basis tensors; andgenerating at least one of the plurality of images by multiplying at least (i) at least a portion of the spatial basis tensor, (ii) at least a portion of at least one of the one or more temporal basis tensors, and (iii) the core tensor.2. The method of claim 1 , further comprising pre-multiplying the core tensor and the at least one of the one or more temporal basis tensors to produce a modified temporal basis tensor claim 1 , wherein the at least ...

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Номер записи: 67
31-03-2022 дата публикации

METHOD FOR CREATING DIFFUSION-WEIGHTED AND NON-DIFFUSION-WEIGHTED SCAN DATA BY MEANS OF MAGNETIC RESONANCE

Номер: US20220099778A1
Автор: Kettinger Adam, Zeller Mario
Принадлежит: Siemens Healthcare GmbH

Techniques are disclosed for capturing scan data of an examination object via a magnetic resonance system. The techniques include capturing a first set of a diffusion-weighted scan data by excitation and, in an acquisition phase, acquiring a first echo signal, wherein before the acquisition phase in a diffusion preparation phase, diffusion gradients are switched for diffusion encoding of the scan data, The techniques additionally include capturing a second set of non-diffusion-weighted scan data by excitation and, in an acquisition phase, acquiring a second echo signal, wherein before the acquisition phase, in a diffusion preparation phase, the same diffusion gradients are switched as are switched for diffusion encoding of the scan data of the first set of diffusion-weighted scan data, although they have no influence on the second echo signal. Diffusion-weighted and non-diffusion-weighted scan data is thereby captured, having identical disturbances caused by eddy currents induced by switched gradients. 1. A method for capturing scan data of an examination object via a magnetic resonance system , comprising:capturing a set of diffusion-weighted scan data via excitation;during a first acquisition phase, acquiring a first echo signal;during a first diffusion preparation phase prior to the first acquisition phase, switching first diffusion gradients for diffusion encoding of the diffusion-weighted scan data;capturing a set of non-diffusion-weighted scan data by excitation;during a second acquisition phase, acquiring a second echo signal; andduring a second diffusion preparation phase prior to the second acquisition phase, switching second diffusion gradients that have the same time and amplitude profile as the first diffusion gradients,wherein the switching of the second diffusion gradients does not influence the second echo signal.2. The method as claimed in claim 1 , wherein the first echo signal and the second echo signal achieve a maximum signal strength claim 1 , ...

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Номер записи: 68
31-03-2022 дата публикации

METHOD FOR ACQUIRING REFERENCE DATA FOR A PHASE CORRECTION IN MAGNETIC RESONANCE TECHNOLOGY

Номер: US20220099780A1
Автор: Kettinger Adam, Zeller Mario
Принадлежит: Siemens Healthcare GmbH

In a method and system for acquiring measurement data reference data for a phase correction of the measurement data, a RF excitation pulse is provided to excite spins in the object under examination, one or more RF refocusing pulses are provided to refocus the spins excited by the RF excitation pulse, measurement data is acquired by recording echo signals of refocused spins excited by the RF excitation pulse by switching readout gradients that alternate in their polarity, at least two echo signals are recorded while switching readout gradients with different polarity acquire reference data, chronologically between the providing of the RF excitation pulse and the acquisition of the measurement data, and correction data is determined for phase correction of phase errors contained in the measurement data based on the acquired reference data. 1. A method for acquiring measurement data of an object under examination and for acquiring reference data for a phase correction of the measurement data using a magnetic resonance (MR) system , the method comprising:providing a radio frequency (RF) excitation pulse to excite spins in the object under examination;providing one or more RF refocusing pulses to refocus the spins excited by the RF excitation pulse;acquiring measurement data by recording echo signals of refocused spins excited by the RF excitation pulse by switching readout gradients that alternate in their polarity;chronologically between the providing of the RF excitation pulse and the acquisition of the measurement data, recording at least two echo signals while switching readout gradients with different polarity acquire reference data; andbased on the acquired reference data, determining correction data for phase correction of phase errors contained in the measurement data.2. The method as claimed in claim 1 , wherein the reference data is acquired immediately prior to and/or immediately after the one or more RF refocusing pulses switched between the RF excitation ...

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Номер записи: 69
12-03-2020 дата публикации

Ultrafast MRI System and Method

Номер: US20200081087A1
Автор: HUTCHINSON Michael
Принадлежит:

Magnetic Resonance Imaging (MRI), which is given the acronym ULTRA (Unlimited Trains of Radio Acquisitions), can eliminate magnetic gradient reversals and allow simultaneous MR signal acquisition from the entire object volume in each of a multitude of very small receiver coils arranged in a 3D array around the imaging volume, except for gradient reversals and/or RF pulses for refocusing spins into echoes. This permits a rate of MR signal acquisition that is greatly increased (e.g. 256 times) compared with existing techniques, with a full 3D image constructed in as little as 1 millisecond. Furthermore, noise—both audible and electrical—is substantially reduced. The advantages over conventional MRI include: 1. A magnetic resonance imaging (MRI) system configured to simultaneously acquire MR signals from an entire three-dimensional (3D) imaging volume that is in a steady main magnetic field , using spatial sensitivity parameters of a multitude of small receiver coils , comprising:{'sub': '0', 'a gradient field generator configured to apply a steady gradient field g to said imaging volume in said main magnetic field Band a radio-frequency (RF) pulse generator configured to apply said initial excitation RF pulse to the imaging volume;'}a multitude of MR signal receiving coils arranged in a 3D array surrounding the imaging volume, said array extending along a first direction as well as transversely to the first direction;each of the receiver coils being configured to simultaneously receive RF energy from the entire imaging volume during MR signals acquisition and to output respective MR signals in response to said initial excitation RF pulse and while said steady gradient field and main magnetic field are present;an MR signal acquisition facility configured to acquire the MR signals;a computer-implemented processor configured to apply image reconstruction algorithms to the MR signals and thereby generate a 3D image of an object in the imaging volume; anda display facility ...

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Номер записи: 70
31-03-2016 дата публикации

METHOD AND APPARATUS FOR ACQUIRING A HIGH-RESOLUTION MAGNETIC RESONANCE IMAGE DATASET OF AT LEAST ONE LIMITED BODY REGION HAVING AT LEAST ONE ANATOMICAL STRUCTURE OF A PATIENT

Номер: US20160093072A1
Автор: Heismann Bjoern
Принадлежит: SIEMENS AKTIENGESELLSCHAFT

In a method and magnetic resonance apparatus for acquiring a high-resolution magnetic resonance image dataset of at least one limited body region having at least one anatomical structure of a patient, an overview image dataset is first acquired, using which an item of position information of the at least one anatomical structure is ascertained, the item of position information designating an exact position of the at least one anatomical structure and/or a relative position of the at least one anatomical structure relative to the reference body region. A high-resolution magnetic resonance image dataset of the anatomical structure is then created using the position information and the high-resolution magnetic resonance image dataset is evaluated. The evaluated high-resolution image data is then made available in electronic form. 1. A method for acquiring a high-resolution magnetic resonance image dataset of at least one limited body region , having at least one anatomical structure therein , of a patient , comprising:operating a magnetic resonance scanner, while a patient is situated therein, to acquire an overview image dataset of the patient comprising image data representing at least one limited body region, comprising at least one anatomical structure, and said overview image also comprising at least one reference body region that is situated in the patient separately from said at least one limited body region;providing said overview image dataset to a computer and, in said computer, determining at least one item of position information of the at least one anatomical structure using the overview image dataset, said at least one item of position information designating at least one of an exact position of said at least one anatomical structure in the patient, and a relative position of said at least one anatomical structure with respect to said at least one reference body region;operating said magnetic resonance scanner to acquire a high-resolution magnetic ...

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Номер записи: 71
30-03-2017 дата публикации

MAGNETIC RESONANCE APPARATUS AND METHOD FOR THE ACQUISITION OF SCAN DATA OF AN EXAMINATION OBJECT

Номер: US20170089994A1
Автор: Feiweier Thorsten
Принадлежит: Siemens Healthcare GmbH

The method and apparatus for the acquisition of scan data of an examination object by execution of a magnetic resonance scanning protocol having at least one suppression module, a relevant volume in the examination object is determined in which the magnetization of the examination object to be examined is to be manipulated and/or the scan data are to be acquired. For each suppression module contained in the scanning protocol, the associated suppression volume in which signals are to be suppressed is determined. The relevant volume that has been determined is optimized by taking account of the determined suppression volumes. Optimized scanning parameters of the scanning protocol are determined such that the best possible scanning conditions prevail in the optimized relevant volume. The scanning protocol is executed as a scanner with the optimized scanning parameters determined and the scan data acquired thereby are made available as a data file. 1. A method for acquiring magnetic resonance scan data from an examination object by operating a magnetic resonance data acquisition scanner according to a scanning protocol that comprises at least one suppression module , said method comprising:in a computer, determining a relevant volume in the examination object, said relevant volume being selected from the group consisting of a volume in which magnetization of nuclear spins in the examination object is to be manipulated in the scanning protocol, and the volume in the examination object from which scan data are to be acquired;for each suppression module in said scanning protocol, determining, in said computer, an associated suppression volume from which magnetic resonance signals are to be suppressed;in said computer, automatically optimizing said relevant volume dependent on each determined suppression volume;in said computer, automatically determining optimized scanning parameters of the scanning protocol that cause best possible scanning conditions to prevail in the ...

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Номер записи: 72
30-03-2017 дата публикации

AQUEOUS CONTRAST AGENTS FOR DYNAMIC MRI AND MRA

Номер: US20170089997A1
Автор: Anderson Stephan, JARA Hernan, MIAN Asim, NORBASH Alex, SAKAI OSAMU, Soto Jorge
Принадлежит: BOSTON MEDICAL CENTER CORPORATION

In a first aspect this invention provides methods comprising administering an aqueous contrast agent to the vascular system of a subject, and performing a magnetic resonance scan to detect the MR signal enhancement effects of the aqueous contrast agent. In embodiments the magnetic resonance scan comprises applying at least one pulse sequence selected from a PD-weighted pulse sequence, a T1-weighted pulse sequence, a T2-weighted pulse sequence, and a D-weighted pulse sequence. In embodiments the magnetic resonance scan comprises applying a T1-weighted pulse sequence. A system for performing perfusion MRI comprising an aqueous contrast solution and an injection apparatus configured to provide a maximum injection rate of the aqueous contrast solution to a subject vascular system of at least about 5 ml/s. is also provided. 1. A method comprising:administering an aqueous contrast agent to the vascular system of a subject, and{'sub': 1', '2, 'performing a magnetic resonance scan to detect the MR signal enhancement effects of the aqueous contrast agent, wherein the magnetic resonance scan comprises applying at least one pulse sequence selected from a PD-weighted pulse sequence, a T-weighted pulse sequence, a T-weighted pulse sequence, and a D-weighted pulse sequence.'}2. The method of claim 1 , wherein the magnetic resonance scan comprises applying a T-weighted pulse sequence.3. The method of claim 2 , wherein the magnetic resonance scan further comprises applying at least one pulse sequence selected from a PD-weighted pulse sequence claim 2 , a T-weighted pulse sequence claim 2 , and a D-weighted pulse sequence.4. The method of claim 1 , further comprising comparing the MR signals at a first period with the MR signals at a second period claim 1 , wherein the first and second periods are different and are selected from before administration of the aqueous contrast agent claim 1 , during administration of the aqueous contrast agent claim 1 , and after administration of the ...

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Номер записи: 73
30-03-2017 дата публикации

METHOD AND APPARATUS FOR ACCELERATED ACQUISITION OF MAGNETIC RESONANCE DATA

Номер: US20170089998A1
Автор: Feiweier Thorsten
Принадлежит: Siemens Healthcare GmbH

In a method and magnetic resonance (MR) apparatus for acquiring MR scan data of an object by execution of a scan sequence in which pulses, at least three RF pulses are radiated for generating an echo signal in a first sub-volume, at a point in time between two of the at least three RF pulses associated with the first sub-volume, at least one other RF pulse is radiated so as to generate an echo signal in another sub-volume, the other sub-volume being different from the first sub-volume. The resulting the echo signals are received and entered into k-space so as to form a datafile that is accessible for reconstructing image data of the object. 1. A method for acquiring a method for acquiring magnetic resonance scan data of an object , comprising:operating a magnetic resonance data acquisition scanner in a scan sequence including radiating at least three radio-frequency (RF) pulses that cause nuclear spins in a first sub-volume of the subject to emit an echo signal;operating said magnetic resonance data acquisition scanner in said scan sequence to radiate, at a point in time between two of said at least three RF pulses associated with said first sub-volume, at least one further RF pulse that causes nuclear spins in another sub-volume of the subject to emit a further echo signal, said other sub-volume being different from said first sub-volume;operating said magnetic resonance data acquisition scanner to acquire said echo signal and said further echo signal and entering values representing the acquired echo signal and further echo signal into a memory organized as k-space, thereby producing k-space data in said memory; andmaking the k-space data available from the memory in electronic form as a datafile.2. A method as claimed in comprising operating said magnetic resonance data acquisition scanner in said scan sequence to cause said at least three RF pulses to generate a stimulated echo in said first sub-volume.3. A method as claimed in comprising operating said magnetic ...

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Номер записи: 74
21-03-2019 дата публикации

Magnetic resonance image analysis method and method for evaluating the risks of radiotherapy

Номер: US20190087688A1
Автор: Cheng-Chia Lee, Huai-Che YANG, Syu-Jyun Peng
Принадлежит: Taipei Veterans General Hospital

The present disclosure provides a magnetic resonance (MR) image analysis method for a patient who underwent radiotherapy. The method includes the steps: receiving an MR image set of a patient and a dose map of a radiotherapy plan; converting the dose intensity distribution of the dose map into the relative spatial positions in the MR image set; selecting a radiation dose and a radiation exposure region, wherein the radiation exposure region has radiation intensity being equal to or higher than the radiation dose; using the radiation exposure region to determine a region of interest (ROI) in the MR image set; classifying the voxels inside the ROI of the MR image set into different clusters according to the grayscale values of the voxels inside the ROI; and calculating the volume or ratios of the different clusters inside the ROI. The present disclosure also provides a method for evaluating risks of radiotherapy.

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Номер записи: 75
19-03-2020 дата публикации

Method to measure tissue texture using nmr spectroscopy with voi length in an analysis direction defined by receiver bandwidth

Номер: US20200088825A1
Автор: Timothy W. James
Принадлежит: Bioprotonics Inc

A method for selective sampling to assess texture of a specimen using magnetic resonance (MR) excites the specimen and refocuses to provide a sample rod within the specimen. An encoding gradient pulse is applied to induce phase wrap creating a spatial encode for a specific k-value and orientation. A low non-zero magnitude gradient is then applied acting as a time dependent phase encode to produce a time varying trajectory through 3D k-space of k-value encodes while simultaneously recording multiple sequential samples of the signal at a sequence of k-values proximate the specific k-value. The receiver bandwidth is set to delineate a length of a VOI within the rod during the data sampling. The samples are then post processed at the sequence of k values, recorded within a time span while the non-zero magnitude gradient is applied, to characterize the textural features of tissue in the VOI.

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Номер записи: 76
01-04-2021 дата публикации

TRAINED IMAGE PROCESSING FOR DIFFUSION WEIGHTED IMAGING AND/OR TURBO SPIN ECHO SEQUENCES WITH FOCUS ON BODY APPLICATIONS

Номер: US20210096204A1
Автор: Benkert Thomas, Grimm Robert, Kiefer Berthold, Nickel Marcel Dominik
Принадлежит: Siemens Healthcare GmbH

In a computer-implemented method of training a machine learning based processor, the processor can be trained to derive image data from signal data sets of multiple spin echo sequences. The trained processor can be configured to perform image processing for Magnetic Resonance Imaging (MRI) to derive the image data. 1. A computer-implemented method of training a machine learning based processor , comprising:receiving a training set of multiple training signal data sets of multiple spin echo sequences;receiving an associated set of ground truth image data;iteratively providing the training signal data sets of the received training set to the processor; anditeratively adapting internal behaviour of the processor, including adapting weights of the machine learning based processor based on a comparison of: (a) image data derived by the processor based on a current one of the iteratively provided training signal data sets, and (b) a current internal behaviour of the processor with the associated ground truth image data.2. The method according to claim 1 , wherein the training signal data sets comprise signal data of a three dimensional (3D) volume including signal data of multiple two dimensional (2D) slices.3. The method according to claim 1 , wherein the training signal data sets comprise real-valued signal data and/or complex-valued signal data.4. The method according to claim 1 , further comprising:{'sub': '0', 'receiving a further training set of supplemental data sets of the multiple spin echo sequences including: B-maps, reverted phase encoding directions, and/or distortion information associated to the multiple training signal data sets; and'}iteratively providing the supplemental data sets associated to the multiple training signal data sets to the processor,wherein, in iteratively adapting the internal behaviour of the processor, the image data is derived by the processor based on the current provided training signal data set, the associated supplemental data ...

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Номер записи: 77
28-03-2019 дата публикации

Correction method and apparatus for magnetic resonance diffusion weighted imaging image

Номер: US20190094325A1
Автор: Kun Zhou, WEI Liu
Принадлежит: SIEMENS AG

In a correction method and apparatus for a magnetic resonance diffusion weighted imaging image, a diffusion weighted imaging image is corrected based on a launch site correction factor and/or a receiving field correction factor. The launch site correction factor is used for correcting inhomogeneity of a launch site, and the receiving field correction factor is used for correcting inhomogeneity of a receiving field. The imaging sequence of the diffusion weighted imaging image is thereby improved and the corresponding image reconstruction of the diffusion weighted imaging image, and the homogeneity of the diffusion weighted imaging image also can be improved, without measuring the intensity of the launch site, which significantly reduces the correction workload and is easy to automate.

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Номер записи: 78
26-03-2020 дата публикации

MAGNETIC RESONANCE DIFFUSION TENSOR IMAGING METHOD AND DEVICE, AND FIBER TRACKING METHOD AND DEVICE

Номер: US20200096592A1
Автор: Lin Mu, Sun Yi, ZHONG Jianhui
Принадлежит: Siemens Healthineers Ltd.

A magnetic resonance diffusion tensor imaging method and corresponding device. The method includes acquiring omnidirectionally sampled diffusion weighted images of a plurality of training samples; performing diffusion tensor model fitting and undersampling for the omnidirectionally sampled diffusion weighted images of each training sample to obtain an omnidirectionally sampled diffusion tensor image and an undersampled diffusion weighted image; training a deep learning network, with the omnidirectionally sampled diffusion tensor images of the plurality of training samples as training targets and the undersampled diffusion weighted images as training data; acquiring undersampled diffusion weighted images of a target object; and inputting the undersampled diffusion weighted images of target objects into the trained deep learning network to obtain the predicted omnidirectionally sampled diffusion tensor images of the target objects. Also, a fiber tracking method and corresponding device. 1. A magnetic resonance diffusion tensor imaging method , comprising:acquiring omnidirectionally sampled diffusion weighted images of a plurality of training samples;performing diffusion tensor model fitting for the omnidirectionally sampled diffusion weighted images of each training sample to obtain an omnidirectionally sampled diffusion tensor image of the training sample, and performing undersampling for the omnidirectionally sampled diffusion weighted images of the training sample in the diffusion weighted direction dimension to obtain the undersampled diffusion weighted image of the training sample;training a deep learning network, with the omnidirectionally sampled diffusion tensor images of the plurality of training samples as training targets and the undersampled diffusion weighted images of the plurality of training samples as training data;acquiring undersampled diffusion weighted images of a target object; andinputting the undersampled diffusion weighted images of the target ...

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Номер записи: 79
03-07-2014 дата публикации

Magnetic resonance method for analyzing pore size distribution

Номер: US20140184224A1
Автор: Dan Benjamini, Uri NEVO
Принадлежит: Ramot at Tel Aviv University Ltd

A method of magnetic resonance analysis of a porous structure is disclosed. The method comprises: obtaining a recorded magnetic resonance signal as a function of both a magnetic resonance wavevector and a magnetic resonance angle, in response to a series of magnetic resonance experiments, each featuring a plurality of pairs of bipolar gradient pulse subsequences being characterized by a respective magnetic resonance wavevector and a respective magnetic resonance angle, where the respective magnetic resonance angle is an angle between gradient directions of the bipolar gradient pulse subsequences. The method further comprises performing an at least three-dimensional analysis of the magnetic resonance signal, so as to extract a pore size distribution from the structure; and issuing a report regarding the analysis.

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Номер записи: 80
08-04-2021 дата публикации

SYSTEM FOR PROCESSING IMAGES TO DETECT PROPERTIES OF SKELETAL MUSCLE

Номер: US20210104045A1
Автор: BLAMIRE Andrew, SCHOFIELD Ian, WHITTAKER Roger
Принадлежит:

Machine readable instructions, a data processing apparatus and a method are provided to determine one or more properties of motor units of skeletal muscle by analyzing a time series of Magnetic Resonance, MR, images representing a slice of a body part to identify signal voids in one or more images of the series. A comparison of at least one characteristic of the identified signal voids in the images is performed with a control data set of MR images produced by applying a controlled stimulus to a motor nerve to establish inherent characteristics of signal voids corresponding to motor units of skeletal muscle. Properties of candidate motor units are analyzed to confirm or reject them as motor units and at least one of: a firing frequency of at least one of the confirmed motor units, a size of at least one of the confirmed motor units, a number of confirmed motor units in a given image area or a shape of at least one of the confirmed motor units is determined. 1. Machine readable instructions stored on a non-transitory machine readable medium , the machine readable instructions upon execution to cause processing circuitry to:receive a time series of Magnetic Resonance, MR, images representing a slice of a body part;analyze the time series of images to identify one or more signal voids in one or more images of the series, a signal void being a localized region of signal attenuation;correlate the identified signal voids with candidate motor units of skeletal muscle, wherein the correlation comprises performing a comparison of at least one characteristic of the identified signal voids in the images with a control data set of MR images produced by applying a controlled stimulus to a motor nerve in control subjects to establish inherent characteristics of signal voids corresponding to motor units of skeletal muscle, the comparison to generate confirmed motor units; andanalyze properties of candidate motor units validated via the comparison as confirmed motor units and ...

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Номер записи: 81
04-04-2019 дата публикации

METHOD OF FAST IMAGING OF NMR PARAMETERS WITH VARIABLY-ACCELERATED SENSITIVITY ENCODING

Номер: US20190101603A1
Автор: Bottomley Paul A., Zhang Yi, Zhou Jinyuan
Принадлежит:

A method of spatially imaging a nuclear magnetic resonance (NMR)parameter whose measurement requires the acquisition of spatially localized NMR signals in a sample includes placing the sample in an MRI apparatus with a plurality of MRI detectors each having a spatial sensitivity map; and applying MRI sequences adjusted to be sensitive to the NMR parameter. At least one of the MRI sequences is adjusted so as to substantially fully sample an image k-space of the sample. The remainder of the MRI sequences is adjusted to under-sample the image k-space. The method further includes acquiring image k-space NMR signal datasets; estimating a sensitivity map of each of the MRI detectors using a strategy to suppress unfolding artefacts; and applying the estimated sensitivity maps to at least one of the image k-space NMR signal data sets to reconstruct a spatial image of NMR signals that are sensitive to the NMR parameter. 1. A method of spatially imaging a nuclear magnetic resonance (NMR) parameter whose measurement requires the acquisition of a plurality of spatially localized NMR signals in a sample , comprising:placing the sample in an MRI apparatus with a plurality of MRI detectors each having a spatial sensitivity map; at least one of the plurality of MRI sequences is adjusted so as to substantially fully sample an image k-space of the sample, and,', 'the remainder of said plurality of MRI sequences is adjusted to under-sample the image k-space of the sample;, 'applying a plurality of MRI sequences wherein each sequence is adjusted to be sensitive to said NMR parameter within the sample, and wherein'}acquiring a plurality of image k-space NMR signal data sets, each responsive to the application of each of said plurality of MRI sequences; 'wherein said strategy is based on data acquired from the substantially fully-sampled MRI sequence; and', 'estimating a sensitivity map of each of the plurality of MRI detectors using a strategy to suppress unfolding artefacts,'}applying ...

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Номер записи: 82
21-04-2016 дата публикации

FIBER TRACTOGRAPHY USING ENTROPY SPECTRUM PATHWAYS

Номер: US20160110911A1
Автор: FRANK Lawrence R., GALINSKY Vitaly L.
Принадлежит:

A method for fiber tractography processes multi-shell diffusion weighted MRI data to identify fiber tracts by calculating intravoxel diffusion characteristics from the MRI data. A transition probability is calculated for each possible path on the lattice, with the transition probability weighted according the intravoxel characteristics. Entropy is calculated for each path and the paths are ranked according to entropy. A geometrical optics algorithm is applied to the entropy data to define pathways, which are ranked according to their significance to generate a map of the pathways. 1. A method for fiber tractography , comprising:acquiring, via an imaging system, diffusion weighted MRI data comprising a plurality of voxels, wherein the plurality of voxels defines a lattice, each voxel connected by a path; calculating intravoxel diffusion characteristics from the MRI data;', 'calculating a transition probability for each path on the lattice, wherein the transition probability is weighted according the intravoxel characteristics;', 'calculating an entropy for each path;', 'ranking the paths between two voxels according to entropy to determine a maximum entropy;', 'calculating a connection between a global structure of the probability with a local structure of the lattice by applying the Fokker-Planck equation to one or more highest ranked paths, wherein potential equals entropy;', 'calculating a location and direction of one or more fiber tracts by applying geometric optics algorithms to the results of the Fokker-Planck equation; and', 'generating an output comprising a display corresponding to the one or more fiber tracts., 'inputting the MRI data into a computer processor data having instructions stored therein for causing the computer processor to execute the steps of2. The method of claim 1 , wherein the Fokker-Planck equation is{'br': None, 'sub': 't', 'i': P+∇', 'LP∇S', 'D∇P,, '∂·()=∇·'}{'sub': 0', '1, 'where P=is probability=P+P, S is the entropy, D is a ...

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Номер записи: 83
20-04-2017 дата публикации

Method and apparatus for magnetic resonance fingerprinting

Номер: US20170108566A1
Автор: Matthias Fenchel
Принадлежит: Siemens Healthcare GmbH

In a method and magnetic resonance apparatus for implementing a magnetic resonance fingerprinting examination of an examination subject, a first signal waveform database containing multiple first database signal waveforms is provided to a processor, and a second signal waveform database is generated therefrom with a fewer number of signal waveforms therein than said multiple first database signal waveforms. A magnetic resonance signal waveform of a voxel of an examination region is acquired using a magnetic resonance fingerprinting method, and this is compared to the second database signal waveforms, and the comparison result is provided in electronic form.

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Номер записи: 84
20-04-2017 дата публикации

SYSTEMS AND METHODS FOR PRESERVING PHASE INFORMATION IN DIFFUSION-WEIGHTED MAGNETIC RESONANCE IMAGING

Номер: US20170108570A1
Автор: Cauley Stephen, EICHNER CORNELIUS, Setsompop Kawin, Wald Lawrence
Принадлежит:

Systems and methods for performing diffusion-weighted magnetic resonance imaging (“MRI”), including reconstructing and analyzing images, while preserving phase information that is traditionally discarded in such applications, are provided. For instance, background phase variations are eliminated, which enables complex-valued data analysis without the usual noise bias. As a result, the systems and methods described here provide an image reconstruction that enables true signal averaging, which increases signal-to-noise ratio (“SNR”) and allows higher contrast in diffusion model reconstructions without a magnitude bias. 1. A method for producing an image , in which background phase variations are removed , from data acquired using a magnetic resonance imaging (MRI) system , the steps of the method comprising:(a) providing diffusion-weighted data that was acquired with an MRI system;(b) reconstructing a complex-valued image from the provided data;(c) estimating background phase variations based on the reconstructed complex-valued image; and(d) producing a complex-valued, phase-corrected image by removing the estimated background phase variations from the reconstructed complex-valued image.2. The method as recited in claim 1 , wherein step (c) includes estimating the background phase variations using at least one of a smoothing algorithm and a denoising algorithm that is designed to produce an image having a phase component equal to the background phase variations.3. The method as recited in claim 2 , wherein the denoising algorithm includes an L1-regularized total variation minimization.4. The method as recited in claim 2 , wherein the at least one of a smoothing algorithm and a denoising algorithm comprises applying a filter to the reconstructed image.5. The method as recited in claim 4 , wherein the filter is a median filter.6. The method as recited in claim 1 , further comprising producing a real-valued claim 1 , phase-corrected image by extracting a real-valued ...

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Номер записи: 85
29-04-2021 дата публикации

METHOD FOR ASCERTAINING A DEVIATION OF AT LEAST ONE GRADIENT FIELD FROM A REFERENCE

Номер: US20210124004A1
Автор: Drobnitzky Matthias, Feiweier Thorsten
Принадлежит:

The disclosure relates to a method for ascertaining a deviation of at least one gradient field of a magnetic resonance system from a reference. The method includes providing at least one first image data set and one second image data set of a phantom with isotropic diffusion properties, recorded with a diffusion-weighted imaging sequence, wherein the first image data set and the second image data set are recorded with different diffusion-weightings along a gradient direction to be tested of the gradient field using the magnetic resonance system. The method further includes ascertaining a map of apparent diffusion coefficients from the image data sets for at least a portion of the image points of the image data sets. The method further includes comparing the apparent diffusion coefficients with the reference. 1. A method for ascertaining a deviation of at least one gradient field of a magnetic resonance system from a reference , the method comprising:providing a first image data set and a second image data set of a phantom with isotropic diffusion properties, recorded with a diffusion-weighted imaging sequence, wherein the first image data set and the second image data set are recorded with different diffusion-weightings along a gradient direction to be tested of the gradient field using the magnetic resonance system;ascertaining a map of apparent diffusion coefficients from the first and second image data sets for at least a portion of the image points of the first and second image data sets; andcomparing the apparent diffusion coefficients with reference values.2. The method of claim 1 , wherein the diffusion weighting is obtained by diffusion gradients along the gradient direction to be tested.3. The method of claim 1 , wherein the providing claim 1 , the ascertaining claim 1 , and the comparing are repeated for a second gradient direction and/or a third gradient direction.4. The method of claim 1 , wherein a first diffusion-weighted imaging sequence with which ...

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Номер записи: 86
28-04-2016 дата публикации

Methods for producing a pulse-pair for magnetic resonance imaging and devices thereof

Номер: US20160116561A1
Автор: Haisam Mohammad ISLAM, Priti Balchandani, Rebecca Emily FELDMAN
Принадлежит: ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI

A method, magnetic resonance imaging computing device, and a non-transitory computer readable medium for producing a pulse pair for magnetic resonance imaging. A pulse pair control signal comprising an adiabatic pulse and a matched phase non-adiabatic pulse is generated. The pulse pair control signal is transformed into a power independent of number of slices pulse pair. The Power Independent of Number of Slices pulse pair control signal is output to a waveform generator to produce the Power Independent of Number of Slices pulse pair in a spin echo sequence.

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Номер записи: 87
26-04-2018 дата публикации

CEREBROSPINAL DIFFUSION PHANTOM

Номер: US20180113186A1
Автор: GMEINER Timotheus Anton, HARRIS Chad Tyler, KERINS FERGAL, STAINSBY Jeff Alan, Thingvold Sheryl Rae, WHITTON GREGORY ALLAN
Принадлежит:

Disclosed herein are cerebrospinal diffusion phantoms which include a housing having a shape and size configured for insertion into a magnetic resonance coil in one or more preselected poses. A scaffold support structure is mounted on an interior of said housing and a plurality of elongated diffusion mimicking members supported on the support array. The elongated diffusion mimicking members are affixed to the scaffold support structure such that elongated diffusion mimicking members extend in directions needed to substantially emulate a 3 dimensional arrangement of cerebrospinal diffusion fiber tracts in a living organism; as well as modules for elimination of resolution based-bias, angular accuracy evaluation, diffusion rate calibration, and quality assurance image referencing. Each elongated diffusion mimicking member includes an aqueous component which can undergo diffusion along the elongated diffusion mimicking member. The phantom includes a cerebrospinal tissue mimic matrix material contained in the housing enveloping the array of elongated diffusion mimicking members. The housing is made of a material whose magnetic susceptibility substantially matches that of the cerebrospinal mimic matrix material. 1. A cerebrospinal diffusion phantom , comprising:a) a housing having a shape and size configured for insertion into a magnetic resonance coil in one or more preselected poses;b) a plurality of elongated diffusion mimicking members contained within the housing, the plurality of elongated diffusion mimicking members positioned such that the elongated diffusion mimicking members extend in directions needed to substantially emulate a three-dimensional (3D) arrangement of cerebrospinal diffusion fiber tracts in a living organism, each elongated diffusion mimicking member including a liquid component which can undergo diffusion along the elongated diffusion mimicking member; andc) a cerebrospinal tissue mimic matrix material contained and sealed in the housing ...

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Номер записи: 88
09-06-2022 дата публикации

FAST DIFFUSION TENSOR MRI USING DEEP LEARNING

Номер: US20220179030A1
Автор: Bilgic Berkin, Huang Susie Yi, Tian Qiyuan
Принадлежит:

Higher quality diffusion metrics and/or diffusion-weighted images are generated from lower quality input diffusion-weighted images using a suitably trained neural network (or other machine learning algorithm). High-fidelity scalar and orientational diffusion metrics can be extracted using a theoretical minimum of a single non-diffusion-weighted image and six diffusion-weighted images, achieved with data-driven supervised deep learning. As an example, a deep convolutional neural network (“CNN”) is used to map the input non-diffusion-weighted image and diffusion-weighted images sampled along six optimized diffusion-encoding directions to the residuals between the input and output high-quality non-diffusion-weighted image and diffusion-weighted images, which enables residual learning to boost the performance of CNN and full tensor fitting to generate any scalar and orientational diffusion metrics. 1. A method for generating a diffusion metric from magnetic resonance image data acquired from a subject , the method comprising: a non-diffusion-weighted image acquired from a subject;', 'at least six diffusion-weighted images acquired from the subject, each diffusion-weighted image corresponding to one of six different diffusion-encoding directions;, '(a) accessing magnetic resonance image data with a computer system, wherein the magnetic resonance image data comprise(b) accessing a neural network with the computer system, wherein the neural network has been trained on training data to learn a mapping from lower quality diffusion-weighted images to ground-truth diffusion-weighted images;(c) inputting at least the at least six diffusion-weighted images contained in the magnetic resonance image data to the neural network using the computer system, generating output as residual image data that represents image differences relative to the ground-truth diffusion-weighted images;(d) generating updated diffusion-weighted images by combining the at least six diffusion-weighted ...

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Номер записи: 89
03-05-2018 дата публикации

System for Characterizing Brain Condition

Номер: US20180116603A1
Автор: Alexander Andrew Lafayette, Dean, III Douglas Carl, Kirk Gregory Russel, Travers Brittany Gail
Принадлежит: WISCONSIN ALUMNI RESEARCH FOUNDATION

A sensitive measure of brain condition simultaneously evaluates multiple measurements of water diffusion in brain tissue combined so as to correct for covariance between the different data types of the multipoint measurements and compares the multipoint measurements to a corresponding multipoint measure representing normal brain tissue to provide a distance indicating a likelihood of atypical brain conditions. 1. A system for assessing brain condition comprising:a magnetic resonance imaging system providing at least two quantitative image data sets and providing different types of data each based on different imaging protocols, each quantitative image data set providing data values at different locations within a brain; anda processor executing a stored program to receive the at least two different quantitative image data sets from the magnetic resonance imaging system and:(a) combining data values of different types of data of the at least two quantitative image data sets at given locations corrected by correlation among the different types of data of the data values; and(b) comparing the corrected data values of the given locations to corresponding data values representing a normal brain to provide a difference revealing a brain condition.2. The system of wherein the at least two different quantitative image data sets provide measures of diffusion of water in the brain.3. The system of wherein the at least two different quantitative image data sets include mean diffusion and fractional anisotropy.4. The system of wherein the at least two different quantitative image data sets include including susceptibility or T2*-weighted imaging without diffusion measurement5. A system for assessing brain condition comprising:a magnetic resource imaging system providing at least two different quantitative image data sets based on different imaging protocols, each quantitative image data set providing data values at different locations within a brain; anda processing system:(a) ...

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Номер записи: 90
03-05-2018 дата публикации

Magnetic resonance diffusion weighted imaging method and apparatus

Номер: US20180120403A1
Автор: Kun Zhou, Le Zhang, Nan Xiao, WEI Liu
Принадлежит: Siemens Healthcare GmbH

In a magnetic resonance diffusion weighted imaging method and apparatus, an excitation pulse flips a magnetization intensity vector of nuclear spins, a subject from the Z direction into the X-Y plane; and a diffusion pulse is applied to the magnetization intensity vector flipped into the X-Y plane in order to perform diffusion weighting. A flip pulse is applied to a magnetization intensity vector that does not meet Carr-Purcell-Meiboom-Gill conditions in the X-Y plane after diffusion weighting in order to flip it back to the Z direction. A data acquisition sequence is activated to acquire imaging data from a residual magnetization intensity vector meeting the Carr-Purcell-Meiboom-Gill conditions in the X-Y plane.

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Номер записи: 91
03-05-2018 дата публикации

SYSTEM, METHOD AND COMPUTER ACCESSIBLE MEDIUM FOR NOISE ESTIMATION, NOISE REMOVAL AND GIBBS RINGING REMOVAL

Номер: US20180120404A1
Автор: FIEREMANS ELS, NOVIKOV DMITRY, VERAART Jelle
Принадлежит:

An exemplary system, method and computer-accessible medium for removing noise and Gibbs ringing from a magnetic resonance (“MR”) image(s), can be provided, which can include, for example, receiving information related to the MR image(s), receiving information related to the MR image(s), and removing the Gibbs ringing from the information by extrapolating data in a k-space from the MR image(s) beyond an edge(s) of a measured portion of the k-space. The data can be extrapolated by formatting the data as a regularized minimization problem(s). A first weighted term of the regularized minimization problem(s) can preserve a fidelity of the extrapolated data, and a second weighted term of the regularized minimization problem(s) can be a penalty term that can be based a norm(s) of the MR image(s), which can be presumed to be sparse 1. A non-transitory computer-accessible medium having stored thereon computer-executable instructions for removing Gibbs ringing from at least one magnetic resonance (“MR”) image , wherein , when a computer arrangement executes the instructions , the computer arrangement is configured to perform procedures comprising:receiving information related to the at least one MR image; andremoving the Gibbs ringing from the information by extrapolating data in a k-space from the at least one MR image beyond at least one edge of a measured portion of the k-space.2. The computer-accessible medium of claim 1 , wherein the computer extrapolates the data based on at least one regularized minimization problem.3. The computer-accessible medium of claim 2 , wherein a first weighted term of the at least one regularized minimization problem preserves a fidelity of the measured portion of the k-space claim 2 , and a second weighted term of the at least one regularized minimization problem is a penalty term that is based on at least one norm of a sparse representation of the at least one MR image.4. The computer-accessible medium of claim 3 , wherein the at least one ...

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Номер записи: 92
14-05-2015 дата публикации

Systems and methods for assessing pulmonary gas transfer using hyperpolarized 129xe mri

Номер: US20150130459A1
Автор: Bastiaan Driehuys, Gary Price Cofer
Принадлежит: Duke University

Methods and systems for assessing pulmonary gas exchange and/or alveolar-capillary barrier status include obtaining at least one MRI image and/or image data of hyperpolarized 129 Xe dissolved in the red blood cells (RBC) in the gas exchange region of the lungs of a patient. The image is sufficiently sensitive to allow a clinician or image recognition program to assess at least one of pulmonary gas exchange, barrier thickness or barrier function based on the 129 Xe MRI image.

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Номер записи: 93
04-05-2017 дата публикации

METHOD AND MAGNETIC RESONANCE APPARATUS FOR MAXWELL COMPENSATION IN SIMULTANEOUS MULTISLICE DATA ACQUISITIONS

Номер: US20170123029A1
Автор: Bhat Himanshu, Hoelscher Uvo, Zeller Mario
Принадлежит: Siemens Healthcare GmbH

In a method and apparatus for acquiring magnetic resonance (MR) data, MR signals are acquired simultaneously from N slices of a subject with an SMS factor of S, the N slices respectively being at different positions from an isocenter of the data acquisition scanner, thereby causing said MR signals to be affected differently by Maxwell terms of magnetic fields that give said MR signals respective signal dephasings that are dependent on the distance of a respective slice from the isocenter. The SMS MR data acquisition sequence is executed with a spacing between each pair of adjacent slices being less than or equal to N/2S. A Maxwell correction algorithm is applied to the acquired k-space data by calculating Maxwell correction gradient moments at an average position between each pair of adjacent slices, thereby generating corrected k-space data wherein the signal dephasing of the MR signals from the N slices is reduced. 1. A method for acquiring magnetic resonance (MR) data , comprising:using a computer to operate an MR data acquisition scanner to execute a simultaneous multi-slice (SMS) MR data acquisition sequence wherein MR signals are acquired simultaneously from N slices of an examination subject, by simultaneously exciting or refocusing N slices with an SMS factor of S, said N slices respectively being at different positions from an isocenter of the data acquisition scanner and thereby causing said MR signals to be affected differently by Maxwell terms of magnetic fields in said data acquisition scanner that give said MR signals respective signal dephasings that are dependent on the distance of a respective slice from the isocenter;using said computer to operate said MR data acquisition scanner to execute said SMS MR data acquisition sequence with a spacing between each pair of adjacent slices, among said N slices, being less than or equal to N/2S;via said computer, entering the acquired MR signals as numerical values representing k-space data in an electronic ...

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Номер записи: 94
25-08-2022 дата публикации

HIGH-RESOLUTION CEREBROSPINAL FLUID-SUPPRESSED T2*-WEIGHTED MAGNETIC RESONANCE IMAGING OF CORTICAL LESIONS

Номер: US20220268867A1
Автор: Beck Erin Savner, Gai Neville Dali, Nair Govind, Reich Daniel Salo
Принадлежит:

Provided herein are methods and systems for high-resolution, cerebrospinal fluid-suppressed T2*-weighted magnetic resonance imaging of cortical lesions. 1. A method of visualizing a cortical lesion in a subject using a magnetic resonance imaging (MRI) system , comprising:(a) acquiring signal data with the MRI system by performing a T2*-weighted sequence, wherein the sequence suppresses cerebrospinal fluid (CSF) signals; and,(b) from the signal data, producing one or more high resolution images, at a computer system of the MRI system, indicative of the presence of the cortical lesion.2. The method of claim 1 , wherein the T2*-weighted sequence is sensitized with a diffusion gradient; and claim 1 , wherein the MRI system produces diffusion-weighted images at a high isotropic resolution of about 0.6 mm or finer.3. The method of claim 2 , wherein the diffusion gradient suppresses CSF signals.4. The method of claim 3 , wherein the b-value of the diffusion gradient is 500-1200 s/mmor higher.5. The method of claim 4 , wherein the T2*-weighted sequence is repeated claim 4 , and wherein the signal data acquired from the T2*-weighted sequences are averaged to produce the one or more high resolution images.6. The method of claim 3 , wherein signal data acquired from the T2*-weighted sequence are motion corrected before producing the one or more high resolution images.7. The method of claim 1 , wherein the T2*-weighted sequence comprises a 3D-T2*-weighted multi-shot acquisition sequence claim 1 , and further comprises a T2-prepared inversion pulse (T2Prep) followed by an inversion pulse claim 1 , wherein the T2Prep suppresses CSF signals.8. The method of claim 7 , wherein the T2Prep comprises a 90-180(4)-90pulse.9. The method of claim 8 , wherein the duration of the T2-Prep pulse is based on the calculated time at which gray matter and white matter signals are equal based on their initial magnetization values.10. The method of claim 9 , wherein the inversion time of the ...

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Номер записи: 95
04-05-2017 дата публикации

METHOD OF CHARACTERIZING MOLECULAR DIFFUSION WITHIN A BODY FROM A SET OF DIFFUSION-WEIGHTED MAGNETIC RESONANCE SIGNALS AND APPARATUS FOR CARRYING OUT SUCH A METHOD

Номер: US20170124294A1
Автор: BARILLOT Christian, COMMOWICK Olivier, Perez Patrick, STAMM Aymeric
Принадлежит:

A computer-implemented method of characterizing molecular diffusion within a body from a set of diffusion-weighted magnetic resonance signals by computing a weighted average of a plurality of multi-compartment diffusion models comprises a same number of compartments, fitted to a set of diffusion-weighted magnetic resonance signals, the weighted average being computed using weights representative of a performance criterion of each of the models; wherein each of the multi-compartment diffusion models comprises a different number of subsets of compartments, the compartments of a same subset being identical to each other. 1. A computer-implemented method of characterizing molecular diffusion within a body from a set of diffusion-weighted magnetic resonance signals by computing a weighted average of a plurality of multi-compartment diffusion models comprising a same number of compartments , fitted to a set of diffusion-weighted magnetic resonance signals , said weighted average being computed using weights representative of a performance criterion of each of said models; wherein each of said multi-compartment diffusion models comprises a different number of subsets of compartments , the compartments of a same subset being substantially identical to each other.2. The computer-implemented method of claim 1 , comprising the steps of:a) fitting a plurality of nested multi-compartment diffusion models with an increasing number of compartments to said signals, each said model being associated to a respective diffusion profile;b) computing a weight, representative of a performance criterion, for each of said models;c) converting said models into respective extended models having a same number of compartments by replicating each compartment of each model a predetermined number of times; andd) determining an averaged model by computing said weighted average of said extended models using the corresponding weights computed at step b).3. The computer-implemented method of claim 2 , ...

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Номер записи: 96
16-04-2020 дата публикации

METHOD OF EVALUATION FOR DISTINGUISHING SLOW MUSCLE AND FAST MUSCLE USING MRI

Номер: US20200116809A1
Автор: Hata Junichi, NAKAMURA Masaya, NAKASHIMA Daisuke, Sera Yasushi
Принадлежит:

Slow muscle and fast muscle can be distinguished by using a QSI method while devising a pulse sequence system and its conditions and using mean displacement, kurtosis or probability at zero displacement as a parameter. A method for typing skeletal muscle non-invasively can be provided. 1. A method for examining skeletal muscle using MRI , comprising measuring a diameter of a muscle fiber using Q-space imaging (QSI).2. The method according to claim 1 , wherein a cell diameter of the muscle fiber reflects a difference between slow muscle and fast muscle and a slow muscle fiber and a fast muscle fiber are distinguished.3. The method according to claim 1 , wherein an imaging method of MRI is a diffusion weighted stimulated echo (DW STE) method.4. The method according to claim 3 , wherein imaging in the DW STE method is performed while setting a TE (echo time) short and extending a diffusion time.5. The method according to claim 3 , comprising:collecting data while extending the diffusion time in the DW STE method in a multi-step manner up to a diffusion time longer than that (200 ms) sufficient for a structure of skeletal muscle to be defined (about 1000 ms);visualizing a structure for exchanging water molecules of a cell membrane, which is specific to a fast muscle fiber and formed of aquaporin (AQP) 4 protein; andvisualizing a slow muscle fiber and a fast muscle fiber by the visualization of a structure for exchanging water molecules.6. The method according to claim 1 , wherein mean displacement claim 1 , kurtosis or probability at zero displacement is used as a parameter in the QSI.7. The method according to claim 1 , wherein in the QSI claim 1 , tensor calculation is performed while incorporating an idea of vector claim 1 , thereby obtaining a λ1 value (axial direction (AD)) claim 1 , a λ2 value claim 1 , a λ3 value (radial direction (RD)) claim 1 , a fractional anisotropy value (FA) and a mean values (MD) of a QSI parameter: mean displacement claim 1 , kurtosis or ...

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Номер записи: 97
27-05-2021 дата публикации

SYSTEM, METHOD AND COMPUTER-ACCESSIBLE MEDIUM FOR CHARACTERIZING PROSTATE MICROSTRUCTURE USING WATER DIFFUSION AND NUCLEAR MAGNETIC RESONANCE RELAXATION

Номер: US20210156944A1
Автор: FIEREMANS ELS, LEMBERSKIY GREGORY, NOVIKOV DMITRY
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An exemplary system, method and computer-accessible medium for characterizing a microstructure of a prostate of a patient can be provided, which can include, for example, generating a magnetic resonance (MR) radiofrequency (RF) pulse(s) by varying (i) a diffusion time, (ii) a diffusion gradient direction, (iii) a diffusion gradient pulse width, or (iv) a diffusion gradient pulse shape, applying the MR RF pulse(s) to the prostate of the patient, receiving a resultant MR signal from the prostate of the patient that can be based on the MR RF pulse(s), determining information regarding a plurality of compartments for the prostate from the resultant MR signal by varying an echo time or a mixing time, and characterizing the microstructure for each of the compartments by applying a microstructural model(s) to each of the compartments. 1. A non-transitory computer-accessible medium having stored thereon computer-executable instructions for characterizing a microstructure of a prostate of a patient , wherein , when a computer arrangement executes the instructions , the computer arrangement is configured to perform procedures comprising:generating at least one magnetic resonance (MR) radiofrequency (RF) pulse by varying at least one of (i) a diffusion time, (ii) a diffusion gradient strength, (iii) a diffusion gradient direction, (iv) a diffusion gradient pulse width, (v) a diffusion gradient pulse shape, (vi) an echo time, (vii) a mixing time, or (viii) a flip angle;applying the at least one MR RF pulse to the prostate of the patient;receiving a resultant MR signal from the prostate of the patient that is based on the at least one MR RF pulse;determining information regarding a plurality of compartments for the prostate from the resultant MR signal; andcharacterizing the microstructure for each of the compartments by applying at least one microstructural model to each of the compartments,wherein the at least one microstructure model includes a plurality of microstructure ...

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Номер записи: 98
31-07-2014 дата публикации

MRI DIFFUSION WEIGHTED IMAGING WITH ESTIMATED MOTION PROBING GRADIENT b-FACTORS BASED ON ACQUIRED APPARENT DIFFUSION COEFFICIENTS FOR EACH PIXEL

Номер: US20140212017A1
Автор: Mitsukazu Kamata, Satoshi Sugiura, Tokunori Kimura
Принадлежит: Toshiba Corp, Toshiba Medical Systems Corp

A magnetic resonance diagnostic apparatus includes a derivation unit to derive an apparent diffusion coefficient regarding a pixel position for each pixel position included in a region of interest in at least two original images obtained by imaging a same imaging region of a same subject using at least two b-factors that are different from each other, respectively, based on pixel values of each of at least two original images regarding the pixel positions, and a first estimation unit to estimate a pixel value obtained by using a b-factor that is different from the at least two b-factors, regarding each pixel position included in the region of interest, based on the apparent diffusion coefficient derived for each pixel position.

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Номер записи: 99
21-05-2015 дата публикации

Error Analysis and Correction of MRI ADC Measurements for Gradient Nonlinearity

Номер: US20150137813A1
Автор: Chenevert Thomas L., Malyarenko Dariya I., Ross Brian D.
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Techniques for correcting gradient non-linearity bias in mean diffusivity measurements by MRI systems are shown and include minimal number of spatial correction terms to achieve sufficient error control using three orthogonal diffusion weighted imaging (DWI) gradients. The correction is based on rotation of system gradient nonlinearity tensor into a DWI gradient frame where spatial bias of b-matrix is described by its Euclidian norm. The techniques obviate time consuming multi-direction acquisition and noise-sensitive mathematical diagonalization of a full diffusion tensor for medium of arbitrary anisotropy. 1. A method of correcting diffusivity measurements of a medium of arbitrary anisotropy , the method comprising;(a.). generating three-dimensional spatial correction maps for an arbitrary set of no more than three orthogonal diffusion gradient waveforms using gradient coil non-linearity characteristics of a magnetic resonance imaging (MRI) scanner,(b.). performing a diffusion weighted MRI scan of the medium using the selected arbitrary set of no more than three orthogonal diffusion gradient waveform at any nominal b-value, and acquiring diffusion weighted images (DWIs),(c.). applying the three-dimensional spatial correction maps to correct intensity of each pixel of the acquired DWIs to compensate for MRI scanner-specific gradient non-linearity bias, and(d.). determining corrected diffusivity images for a mean diffusivity of the medium from the corrected DWIs and nominal b-values.2. The method of claim 1 , wherein the corrected diffusivity images are determined from uncorrected DWIs using corrected three-dimensional b-value maps.3. The method of claim 1 , where the mean diffusivity is the apparent diffusion coefficient (ADC).4. The method of claim 2 , wherein the corrected three-dimensional b-value map for the nominal b-value=band kdiffusion gradient direction is determined as claim 2 ,{'br': None, 'sup': c', 'k, 'i': b', 'r', 'b', 'C', 'r, 'sub': kk', '0, '({ ...

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Номер записи: 100