Nonrigid motion correction in 3D using autofocusing with localized linear translations
A method for providing an magnetic resonance imaging (MRI) with nonrigid motion correction of an object is provided. An MRI excitation is applied to the object. A magnetic field read out from the object using a plurality of sensor coils. Spatially localized motion estimates are obtained for each sensor coil of the plurality of sensor coils. The motion estimates are used for each sensor coil to provide motion correction.
1. A method for providing a magnetic resonance imaging (MRI) with nonrigid motion correction of an object, comprising:
applying an MRI excitation to the object;
reading out magnetic field from the object using a plurality of sensor coils;
obtaining spatially localized motion estimates for each sensor coil of the plurality of sensor coils;
using the localized motion estimates as possible candidates to correct for local motions;
determining a best motion estimate for correction at each spatial location based on an image-based motion metric; and
generating an image with nonrigid motion correction from the determined best motion estimate for correction at each spatial location.
2. The method, as recited in claim 1 , wherein the sensor coils are spaced apart so that different sensor coils sense different 3D motion to build a nonrigid motion model.
3. The method, as recited in claim 2 , further comprising generating a plurality of images showing movement.
4. The method, as recited in claim 2 , further comprising generating a plurality of images showing 3D nonrigid movement.
5. The method, as recited in claim 4 , wherein the reading out the magnetic field uses an acquisition trajectory with navigators.
6. The method, as recited in claim 5 , wherein the acquisition trajectory is a modified Butterfly trajectory.
7. The method, as recited in claim 6 wherein the modified Butterfly trajectory has navigators that acquire data along each axis.
8. The method, as recited in claim 7 , wherein the obtaining spatially localized motion estimates, comprises weighting the read out magnetic field to avoid data corruption, such as from eddy currents and gradient hysteresis.
9. The method, as recited in claim 8 , wherein the obtaining spatially localized motion estimates, further comprise performing coil compression.
10. The method, as recited in claim 1 , further comprising generating a plurality of images showing movement.
11. The method, as recited in claim 1 , further comprising generating a plurality of images showing 3D nonrigid movement.
12. The method, as recited in claim 1 , wherein the reading out the magnetic field uses an acquisition trajectory with navigators.
13. The method, as recited in claim 7 , wherein the obtaining spatially localized motion estimates, comprises weighting the read out magnetic field to avoid data corruption, such as from eddy currents and gradient hysteresis.
14. The method, as recited in claim 1 , wherein the obtaining spatially localized motion estimates, further comprises combining data from a plurality of sensor coils into virtual coils.
15. The method, as recited in claim 1 , further comprising a strategically planned data acquisition scheme to reduce the severity of image artifacts from motion corruption.
16. The method, as recited in claim 1 , further comprising generating additional motion estimates based on a weighted summation of previously generated spatially localized motion estimates.
17. The method, as recited in claim 1 , further comprising:
generating a plurality of motion fields based on the spatially localized motion estimate; and
using the motion fields to correct each spatial location to build a nonrigid motion model.
18. A method for providing an magnetic resonance imaging (MRI) with nonrigid motion correction of an object, comprising:
applying an MRI excitation to the object;
reading out magnetic field from the object using a plurality of sensor coils, wherein the sensor coils are spaced apart so that different sensor coils sense different 3D motion, wherein the reading out the magnetic field uses an acquisition trajectory with navigators;
obtaining spatially localized motion estimates for each sensor coil of the plurality of sensor coils;
using the motion estimates for each sensor coil to provide motion correction; and
using the localized motion estimates as possible candidates to correct for local motions;
determining a best motion estimate for correction at each spatial location based on a motion metric; and
generating an image with nonrigid motion correction from the determined best motion estimate for correction at each spatial location.
19. A method for providing a magnetic resonance imaging (MRI) with nonrigid motion correction of an object, comprising:
applying an MRI excitation to the object;
reading out magnetic field from the object using a plurality of sensor coils, wherein the reading out the magnetic field uses an acquisition trajectory with navigators, wherein the acquisition trajectory is a modified Butterfly trajectory;
obtaining spatially localized motion estimates for each sensor coil of the plurality of sensor coils; and
generating an image with nonrigid motion correction through localized 3D autofocusing, using the motion estimates for each sensor coil to provide nonrigid motion correction.
20. The method, as recited in claim 19 wherein the modified Butterfly trajectory has navigators that acquire data along each axis.