27-06-2013 дата публикации
Номер: US20130162251A1
A parallel imaging (PI) method has been frequently used as a method for shortening an image acquisition time in the MRI field. The PI technique is a method for acquiring data using multi-channel coils, that is, several coils, when acquiring the data in MRI. According to this technique, data, the amount of which is smaller than that when the data is obtained using only one coil, is acquired, and then an image is obtained using coil information. According to an embodiment, a new image reconstruction method is proposed which adopts an expectation maximization (EM) technique that is different from the existing GRAPPA or SENSE technique when an image is obtained using PI data acquired through the radial trajectory. 1. An MR imaging method for radial trajectory , comprising:a first step of calculating sensitivity information S from pre-acquired data through an MRI device;a second step of receiving an input of a signal g that is radially sampled through parallel coils in the MRI device and obtaining two offset-adjusted signals gL′ and gU′ through increasing/decreasing a boundary value;{'sub': 0', '0', '0, 'a third step of receiving an input of an initial image value ffrom an outside and obtaining two offset-adjusted signals fL′ and fU′;'}{'sub': 0', '0, 'a fourth step of obtaining projection signals PL and PU using the sensitivity information S obtained in the first step and the two offset-adjusted signals fL′ and fU′ of the initial image value obtained in the third step;'}a fifth step of obtaining coefficients real_cL, imag_cL, real_cU, and imag_cU using the sensitivity information S obtained in the first step, the offset-adjusted signals gL′ and gU′ obtained in the second step, and the projection signals PL and PU obtained in the fourth step;{'sub': 0', '0', '1, 'a sixth step of reconfiguring an image by multiplying the coefficients real_cL, imag_cL, real_cU, and imag_cU obtained in the fifth step by the offset-adjusted signals fL′ and fU′ of the initial image value ...
Подробнее
