Magnetic resonance imaging apparatus and image processing method thereof

Patent metadata

Field	Value
Publication number	US-2016170002-A1
Application number	US-201514965959-A
Country	US
Kind code	A1
Filing date	Dec 11, 2015
Priority date	Dec 11, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

A magnetic resonance imaging apparatus includes a gradient magnetic field controller which applies a spatial encoding gradient to a plurality of slices and applies a gradient magnetic field in a first direction with respect to the plurality of slices, a radio frequency (RF) receiver which receives respective magnetic resonance signals from each of the plurality of slices undersampled in a second direction different from the first direction, and an image processor which generates a respective magnetic resonance image of each of the plurality of slices based on the magnetic resonance signals received from the plurality of slices.

First claim

What is claimed is:

1 . A magnetic resonance imaging apparatus comprising:
a gradient magnetic field controller configured to apply a spatial encoding gradient to a plurality of slices and to apply a gradient magnetic field in a first direction to the plurality of slices; a radio frequency (RF) receiver configured to receive, for each of the plurality of slices, a respective magnetic resonance signal which is undersampled in a second direction which is different from the first direction; and an image processor configured to generate, based on the respective magnetic resonance signal of each of the plurality of slices, a respective magnetic resonance image of the corresponding one of the plurality of slices.

2 . The magnetic resonance imaging apparatus of claim 1 , wherein the spatial encoding gradient comprises a frequency encoding gradient defined as a magnetic field component which includes a gradient with respect to a frequency direction, a phase encoding gradient defined as a magnetic field component which includes a gradient with respect to a phase direction, and a slice selection gradient defined as a magnetic field component which includes a gradient with respect to a slice direction.

3 . The magnetic resonance imaging apparatus of claim 2 , wherein the first direction is the slice direction and the second direction is the phase direction which is different from the first direction.

4 . The magnetic resonance imaging apparatus of claim 2 , wherein the gradient magnetic field controller is further configured to apply a gradient magnetic field in the first direction to the plurality of slices while the frequency encoding gradient is applied to the plurality of slices.

5 . The magnetic resonance imaging apparatus of claim 2 , wherein the RF receiver is further configured to receive each respective magnetic resonance signal in a superposed state in one repetition time section.

6 . The magnetic resonance imaging apparatus of claim 5 , wherein each respective magnetic resonance signal comprises shifted position information in the frequency direction as a result of the gradient magnetic field in the first direction being applied to the plurality of slices.

7 . The magnetic resonance imaging apparatus of claim 1 , wherein the image processor is further configured to interpolate a non-measured magnetic resonance signal by using a parallel imaging technique and to generate the respective magnetic resonance image of each corresponding one of the plurality of slices by using a multi-slice imaging technique.

8 . A magnetic resonance imaging apparatus comprising:
a gradient magnetic field controller configured to apply a spatial encoding gradient to each of a first slice and a second slice, and to apply a slice selection gradient to each of the first slice and the second slice; a radio frequency (RF) receiver configured to receive a first magnetic resonance signal which relates to the first slice and which includes shifted position information in a frequency direction as a result of the slice selection gradient being applied to the first slice and undersampled in a phase direction, and to receive a second magnetic resonance signal which relates to the second slice and which includes shifted position information in the frequency direction as a result of the slice selection gradient being applied to the second slice and undersampled in the phase direction; and an image processor configured to generate a respective magnetic resonance image of each of the first and second slices based on the received first and second magnetic resonance signals.

9 . The magnetic resonance imaging apparatus of claim 8 , wherein the RF receiver is further configured to receive the first and second magnetic resonance signals in a superposed state in one repetition time.

10 . The magnetic resonance imaging apparatus of claim 9 , wherein the image processor is further configured to separate the first and second magnetic resonance signals in the superposed state, based on a difference in coil sensitivity information between the first slice and the second slice.

11 . A method for generating a magnetic resonance image, the method comprising:
applying a spatial encoding gradient to a plurality of slices and a gradient magnetic field in a first direction to the plurality of slices; receiving, for each of the plurality of slices, a respective magnetic resonance signal which is undersampled in a second direction which is different from the first direction; and generating, based on the received respective magnetic resonance signal of each of the plurality of slices, a respective magnetic resonance image of the corresponding one of the plurality of slices.

12 . The method of claim 11 , wherein the spatial encoding gradient comprises a frequency encoding gradient defined as a magnetic field component which includes a gradient with respect to a frequency direction, a phase encoding gradient defined as a magnetic field component which includes a gradient with respect to a phase direction, and a slice selection gradient defined as a magnetic field component which includes a gradient with respect to a slice direction.

13 . The method of claim 12 , wherein the first direction is the slice direction and the second direction is the phase direction which is different from the first direction.

14 . The method of claim 12 , wherein the applying the gradient magnetic field in the first direction comprises applying the gradient magnetic field in the first direction to the plurality of slices while the frequency encoding gradient is applied to the plurality of slices.

15 . The method of claim 12 , wherein the receiving each respective magnetic resonance signal comprises receiving each respective magnetic resonance signal in a superposed state in one repetition time section.

16 . The method of claim 15 , wherein each respective magnetic resonance signal comprises shifted position information in the frequency direction as a result of the applying the gradient magnetic field in the first direction to the plurality of slices.

17 . The method of claim 11 , wherein the generating the respective magnetic resonance image of each corresponding one of the plurality of slices comprises:
interpolating a non-measured magnetic resonance signal by using a parallel imaging technique; and generating the respective magnetic resonance image of each corresponding one of the plurality of slices by using a multi-slice imaging technique.

18 . A method for generating a magnetic resonance image, the method comprising:
applying a spatial encoding gradient to each of a first slice and a second slice; applying a slice selection gradient defined as a magnetic field component which includes a gradient with respect to a slice direction to each of the first slice and the second slice; receiving a first magnetic resonance signal which relates to the first slice and which includes shifted position information in a frequency direction as a result of the applying the slice selection gradient to the first slice and being undersampled in a phase direction, and receiving a second magnetic resonance signal which relates to the second slice and which includes shifted position information in the frequency direction as a result of the applying the slice selection gradient to the second slice and being undersampled in the phase direction; and generating a respective magnetic resonance image of each of the first and second slices based on the received first and second magnetic resonance signals.

Assignees

• Samsung Electronics Co Ltd
• Korea Advanced Inst Sci & Tech

Inventors

• Park Hyun-Wook
• Kim Dong-Chan
• Oh Chang-Heun
• Seo Hyun-Seok

Classifications

• G01R33/56554 Primary

  caused by acquiring plural, differently encoded echo signals after one RF excitation, e.g. correction for readout gradients of alternating polarity in EPI · CPC title

• G01R33/385

  using gradient magnetic field coils · CPC title

• G01R33/5611

  Parallel magnetic resonance imaging, e.g. sensitivity encoding [SENSE], simultaneous acquisition of spatial harmonics [SMASH], unaliasing by Fourier encoding of the overlaps using the temporal dimension [UNFOLD], k-t-broad-use linear acquisition speed-up technique [k-t-BLAST], k-t-SENSE (structural details of arrays of sub-coils G01R33/3415) · CPC title

• G01R33/4835 Primary

  of multiple slices · CPC title

• A61B5/055 Primary

  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging · CPC title