System, apparatus, and method for incremental motion correction in magnetic resonance imaging

1. An apparatus for incremental motion correction in magnetic resonance imaging, the apparatus comprising:

processing circuitry configured to

estimate an intermediate image from a first section of k-space, the first section of the k-space corresponding to acquisition time points within a magnetic resonance scan of a subject, the corresponding acquisition time points within the magnetic resonance scan being associated with shots of the k-space determined to have minimal motion,

estimate motion parameters of a second section of the k-space using the estimated intermediate image,

combine data from the first section of the k-space with data from the second section of the k-space according to the estimated motion parameters, and

reconstruct the combined data of the k-space to generate a final image.

2. The apparatus according to claim 1 , wherein the processing circuitry is further configured to

order N shots of the k-space of the magnetic resonance scan chronologically, and

select, as the first section of the k-space, a first M shots of the ordered N shots of the k-space of the magnetic resonance scan.

3. The apparatus according to claim 1 , wherein the processing circuitry is further configured to

calculate a motion score for each of N shots of the k-space of the magnetic resonance scan,

rank the N shots of the k-space of the magnetic resonance scan according to the calculated motion score for each of the N shots of the k-space, the ranked N shots being acquired over a full time period of the magnetic resonance scan, and

select, as the first section of the k-space, a section of the k-space that includes a highest ranked shot of the N shots of the k-space and at least one other of the ranked N shots.

4. The apparatus according to claim 1 , wherein the processing circuitry is further configured to

update a vector of motion parameters to include the estimated motion parameters of the second section of the k-space, the vector of motion parameters including motion parameters corresponding to the first section of the k-space.

5. The apparatus according to claim 4 , wherein the processing circuitry is further configured to reconstruct the combined data of the k-space to generate the final image based on the updated vector of motion parameters.

6. The apparatus according to claim 4 , wherein the vector of motion parameters includes, for each combined section of the k-space, two translational values and one rotational value.

7. The apparatus according to claim 1 , wherein the processing circuitry is further configured to combine the data from the first section of the k-space with the data from the second section of the k-space according to the estimated motion parameters by

calculating a value of a data consistency metric for the second section of the k-space, and

discarding, when a comparison indicates the calculated value of the data consistency metric is below a threshold of acceptability, the data from the second section of the k-space.

8. The apparatus according to claim 1 , wherein the processing circuitry is further configured to

calculate a data consistency error value for each of N shots of the k-space of the magnetic resonance scan, and

select the first section of the k-space based on the data consistency error values calculated for each of the N shots of the k-space of the magnetic resonance scan.

9. A method for incremental motion correction in magnetic resonance imaging, comprising:

estimating, by processing circuitry, an intermediate image from a first section of k-space, the first section of the k-space corresponding to acquisition time points within a magnetic resonance scan of a subject, the corresponding acquisition time points within the magnetic resonance scan being associated with shots of the k-space determined to have minimal motion;

estimating, by the processing circuitry, motion parameters of a second section of the k-space using the estimated intermediate image;

combining, by the processing circuitry, data from the first section of the k-space with data from the second section of the k-space according to the estimated motion parameters; and

reconstructing, by the processing circuitry, the combined data of the k-space to generate a final image.

10. The method according to claim 9 , further comprising

ordering, by the processing circuitry, N shots of the magnetic resonance scan chronologically, and

selecting, by the processing circuitry and as the first section of the k-space, a first M shots of the ordered N shots of the magnetic resonance scan.

11. The method according to claim 9 , further comprising

calculating, by the processing circuitry, a motion score for each of N shots of the magnetic resonance scan,

ranking, by the processing circuitry, the N shots of the magnetic resonance scan according to the calculated motion score for each of the N shots, the ranked N shots being acquired over a full time period of the magnetic resonance scan, and

selecting, by the processing circuitry and as the first section of the k-space, a section of the k-space that includes a highest ranked shot of the N shots of the k-space and at least one other of the ranked N shots.

12. The method according to claim 9 , further comprising

updating, by the processing circuitry, a vector of motion parameters to include the estimated motion parameters of the second section of the k-space, the vector of motion parameters including motion parameters corresponding to the first section of the k-space.

13. The method according to claim 12 , wherein the reconstructing the combined data of the k-space to generate the final image is based on the updated vector of motion parameters.

14. The method according to claim 12 , wherein the updated vector of motion parameters includes, for each combined section of the k-space, two translational values and one rotational value.

15. The method according to claim 9 , wherein the combining the data from the first section of the k-space with the data from the second section of the k-space according to the estimated motion parameters includes

calculating, by the processing circuitry, a value of a data consistency metric for the second section of the k-space, and

discarding, by the processing circuitry and when a comparison indicates the calculated value of the data consistency metric is below a threshold of acceptability, the data from the second section of the k-space.

16. A non-transitory computer-readable storage medium storing computer-readable instructions that, when executed by a computer, cause the computer to perform a method for incremental motion correction in magnetic resonance imaging, comprising:

estimating an intermediate image from a first section of k-space, the first section of the k-space corresponding to acquisition time points within a magnetic resonance scan of a subject, the corresponding acquisition time points within the magnetic resonance scan being associated with shots of the k-space determined to have minimal motion;

estimating motion parameters of a second section of the k-space using the estimated intermediate image;

combining data from the first section of the k-space with data from the second section of the k-space according to the estimated motion parameters; and

reconstructing the combined data of the k-space to generate a final image.

17. The non-transitory computer-readable storage medium according to claim 16 , further comprising

ordering N shots of the magnetic resonance scan chronologically, and

selecting, as the first section of the k-space, a first M shots of the ordered N shots of the magnetic resonance scan.

18. The non-transitory computer-readable storage medium according to claim 16 , further comprising

calculating a motion score for each of N shots of the magnetic resonance scan,

ranking the N shots of the magnetic resonance scan according to the calculated motion score for each of the N shots, the ranked N shots being acquired over a full time period of the magnetic resonance scan, and

selecting, as the first section of the k-space, a section of the k-space that includes a highest ranked shot of the N shots of the k-space and at least one other of the ranked N shots.

19. The non-transitory computer-readable storage medium according to claim 16 , further comprising

updating a vector of motion parameters to include the estimated motion parameters of the second section of the k-space, the vector of motion parameters including motion parameters corresponding to the first section of the k-space.

20. The non-transitory computer-readable storage medium according to claim 16 , wherein the combining the data from the first section of the k-space with the data from the second section of the k-space according to the estimated motion parameters includes

calculating a value of a data consistency metric for the second section of the k-space, and

discarding, when the comparison indicates the calculated value of the data consistency metric is below a threshold of acceptability, the data from the second section of the k-space.