US 12,032,050 B2
Magnetic resonance imaging apparatus, sensitivity distribution calculation method, and sensitivity distribution calculation program
Toru Shirai, Tokyo (JP); Yasuhiro Kamada, Tokyo (JP); Masahiro Takizawa, Tokyo (JP); and Hisaaki Ochi, Tokyo (JP)
Assigned to FUJIFILM HEALTHCARE CORPORATION, Chiba (JP)
Appl. No. 16/771,449
Filed by Hitachi, Ltd., Tokyo (JP)
PCT Filed Sep. 13, 2018, PCT No. PCT/JP2018/034007
§ 371(c)(1), (2) Date Jun. 10, 2020,
PCT Pub. No. WO2019/181006, PCT Pub. Date Sep. 26, 2019.
Claims priority of application No. 2018-053210 (JP), filed on Mar. 20, 2018.
Prior Publication US 2021/0068700 A1, Mar. 11, 2021
Int. Cl. G01R 33/56 (2006.01); G01R 33/34 (2006.01); G01R 33/48 (2006.01); G01R 33/54 (2006.01); G01R 33/561 (2006.01)
CPC G01R 33/5611 (2013.01) [G01R 33/34 (2013.01); G01R 33/4822 (2013.01); G01R 33/54 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A magnetic resonance imaging apparatus comprising:
a measurement unit that includes a reception coil having a plurality of channels, and measures a nuclear magnetic resonance signal of a subject for each of the channels of the reception coil; and
an image computation unit that creates an image of the subject by using a sensitivity distribution for each channel of the reception coil and a channel image of plural channel images obtained from the nuclear magnetic resonance signal measured by the measurement unit for each channel,
wherein the image computation unit includes a sensitivity distribution calculation unit that calculates a sensitivity distribution on a k-space for each channel by using the channel images and a composite image obtained by combining the channel images,
wherein the calculated sensitivity distribution does not depend on a shape or a structure of the subject, and
wherein the sensitivity distribution calculation unit:
obtains the composite image by:
performing a Fourier transform to convert k-space data into image data,
cutting out slices of the image data for each channel, and
combining the cut out slices to generate the composite image,
after calculating the composite image:
converts the channel images and the composite image into k-space data, and
calculates a sensitivity distribution frequency component from the k-space data of the composite image by:
calculating a weighting coefficient corresponding to a respective frequency component of a reception coil, and
convolution-integrating the weighting coefficient and a δ-function, and an actual space conversion unit that converts the frequency component after the convolution integration into actual space data.