System, method, software arrangement and computer-accessible medium for providing real-time motion correction by utilizing clover leaf navigators

• US 7,358,732 B2
• Filed: 10/24/2005
• Issued: 04/15/2008
• Est. Priority Date: 10/24/2005
• Status: Expired due to Fees

• Current Assignee: The General Hospital Corporation (Mass General Brigham, Inc.)
• Original Assignee: The General Hospital Corporation (Mass General Brigham, Inc.)
• Inventors: Van Der Kouwe, André J. W., Dale, Anders M.
• Primary Examiner(s): SHRIVASTAV, BRIJ B
• Application Number:
  US11/257,925
• Publication Number:
  US 20070090837A1
• Time in Patent Office: 904 Days
• Field of Search: 324300-322, 600407-445
• US Class Current: 324/309
• CPC Class Codes: G01R 33/5676 Gating or triggering based on an MR signal, e.g. involving one or more navigator echoes for motion monitoring and correction

Abstract

A system, method, software arrangement and computer-accessible medium for correcting for a motion of an object are provided. In this system, method, software arrangement and computer-accessible medium, the navigator data and map data can be obtained for the object. Then, the navigator data is compared with the map to generate comparison data. Thereafter, a translation and/or a rotation of the object is corrected in real-time as a function of the comparison data. The navigator can be preferably a clover leaf navigator. In one exemplary embodiment, a scanning sequence can be used to determine a position of the object. For example, this scanning sequence may include a signal portion which includes at least one radio frequency signal, a navigator portion which includes at least one clover leaf navigator, and a spoiler portion provided for reducing a signal magnitude of the scanning sequence. The navigator is provided for allowing a measurement of the rotation and/or the translation of the object. The measurement can be adjusted by correcting for phase encoding effects, shimming errors, and B0 drifts. A feedback control system may be provided to repeatedly correct the measurement of the rotation and translation of the object. The navigator portion can advantageously be provided between the signal portion and the spoiler portion. The system, method, software arrangement and computer-accessible medium may be implemented when multiple coils are present.

Claims

1. A method of correcting or compensating for a motion of an object during a magnetic resonating imaging (“

MRI”

) scan of the object, comprising the steps of;

obtaining first data for the object, the first data including data defining a navigator and a path of the navigator;

obtaining second data for the object, the second data defining a map of the object;

determining whether at least one of a correction or a compensation of at least one of a translation or a rotation is to take place, wherein the correction or the compensation is performed based on the first data, the second data and deviations of at least one of the first data or the second data.

2. The method according to claim 1, wherein the determining step includes comparing the first data with the second data to obtain comparison data.

3. The method according to claim 2, wherein the determining step is performed repeatedly in real time.

4. The method according to claim 3, wherein the path of the navigator comprises a first segment and a second segment, the first segment comprising straight traversals through a center of a k-space region corresponding to positional data for the object, and the second segment comprising arcs in at least one perpendicular plane with respect to the k-space region.

5. The method according to claim 1, wherein the navigator includes a plurality of gradients.

6. The method according to claim 1, wherein the path of the navigator is defined by the first data is a three-dimensional structure representation.

7. The method according to claim 6, wherein the structure is provided in a k-space region, and wherein the k-space region is spherical.

8. The method according to claim 7, wherein the path of the navigator is defined by the first data lies substantially outside the k-space region.

9. The method according to claim 8, wherein the path of the navigator is defined by the first data lies substantially within the k-space region.

10. The method according to claim 1, wherein the second data is obtained as a function of the first data.

11. The method according to claim 1, wherein the rotation of the object is described using quaternions.

12. The method according to claim 2, wherein the determining step further comprises the substep of modifying the second data as a function of the comparison data.

13. The method according to claim 12, wherein the determining step further comprises the substep of modifying the second data as a function of the comparison data.

14. The method according to claim 1, further comprising the step of repeatedly modifying at least one of the translation or the rotation of the object using a feedback control system.

15. The method according to claim 1, wherein the deviations of at least one of the first data or the second data comprise deviations of at least one of a phase encoding gradient, a position of the object in a B0 field after shimming, or a drift in the B0 field.

16. The method according to claim 1, wherein the determining step further comprises correcting or compensating for at least one of the translation or the rotation of the object when multiple coils are used during the MRI scan.

17. The method according to claim 1, wherein the determining step comprises estimating and removing out-of-plane effects from the navigator.

18. The method according to claim 1, wherein the object is an anatomical structure.

19. A system for correcting for a motion of an object during an MRI scan of the object, comprising:

a processor configured to;

obtain first data for the object, the first data defining a navigator and a path of the navigator;

obtain second data for the object, the second data defining a map of the object; and

determine whether at least one of a correction or a compensation of at least one of a translation or a rotation is to take place, wherein the correction or the compensation is performed based on the first data, the second data, and deviations of at least one of the first data or the second data.

20. The system of claim 19, wherein the deviations of at least one of the first data or the second data comprise deviations of at least one of a phase encoding gradient, a position of the object in a B0 field after shimming, or a drift in the B0 field.

21. The system of claim 19, wherein the processor is further configured to repeatedly modify at least one of the translation or the rotation of the object using a feedback control system.

22. A software arrangement provided for correcting a motion of an object during an MRI scan of the object, comprising:

a first module programmed to obtain first data for the object, the first data defining a navigator and a path of the navigator;

a second module programmed to obtain second data for the object, the second data defining a map of the object; and

a third module programmed to determine whether at least one of a correction or a compensation of at least one of a translation or a rotation is to take place, wherein the correction or the compensation is performed based on the first data, the second data, and deviations of at least one of the first data or the second data.

23. The software arrangement of claim 22, wherein the deviations of at least one of the first data or the second data comprise deviations of at least one of a phase encoding gradient, a position of the object in a B0 field after shimming, or a drift in the B0 field.

24. The software arrangement of claim 22, further comprising a fourth module programmed to repeatedly correct at least one of the translation or the rotation using a feedback control system.

25. A computer-accessible medium which includes and facilitates an execution of a set of instructions that are provided for correcting a motion of an object during an MRI scan of the object, wherein, when a processing arrangement executes the instructions, the processing arrangement executes the steps comprising:

obtaining first data for the object, the first data defining a navigator and a path of the navigator;

obtaining second data for the object, the second data defining a map of the object; and

determining whether at least one of a correction or a compensation of at least one of a translation or a rotation is to take place, wherein the correction or the compensation is performed based on the first data, the second data, and deviations of at least one of the first data or the second data.

26. The computer-accessible medium of claim 25, wherein the deviations of at least one of the first data or the second data comprise deviations of at least one of a phase encoding gradient, a position of the object in a B0 field after shimming, or a drift in the B0 field.

27. The computer-accessible medium of claim 25, wherein the processing arrangement repeatedly corrects at least one of the translation or the rotation using a feedback control system.

28. A method of obtaining information during a magnetic resonating imaging (“

MRI”

) scan of at least one portion of an object, comprising the steps of;

obtaining first data for the object, the first data including data defining a navigator and a path of the navigator;

obtaining second data for the object, the second data defining a map of the object;

determining whether at least one of a correction or a compensation of at least one of a shim, B0 drift, a combination of rotation, translation shim and drift associated with the object, wherein the correction or compensation is performed based on the first data, the second data and deviations of at least one of the first data or the second data.

29. A software arrangement provided for obtaining information for an object during an MRI scan of the object, comprising:

a first module programmed to obtain first data for the object, the first data including data defining a navigator and a path of the navigator;

a second module programmed to obtain second data for the object, the second data defining a map of the object;

a third module programmed to determine whether at least one of a correction or a compensation of at least one of a shim, B0 drift, a combination of rotation, translation shim and drift associated with the object, wherein the at least one of the correction or the compensation is performed based on the first data, the second data and deviations of at least one of the first data or the second data.

30. A system for obtaining information for an object during an MRI scan of the object, comprising:

a processor configured to;

obtain first data for the object, the first data including data defining a navigator and a path of the navigator;

obtain second data for the object, the second data defining a map of the object;

determine whether at least one of a correction or a compensation of at least one of a shim, B0 drift, a combination of rotation, translation shim and drift associated with the object, wherein the at least one of the correction or the compensation is performed based on the first data, the second data and deviations of at least one of the first data or the second data.

31. A computer-accessible medium which includes and facilitates an execution of a set of instructions that are provided for obtaining information during a magnetic resonating imaging (“

MRI”

) scan of at least one portion of an object, wherein when a processing arrangement executes the instructions, the processing arrangement executes the steps comprising;

obtaining first data for the object, the first data including data defining a navigator and a path of the navigator;

obtaining second data for the object, the second data defining a map of the object;

determining whether at least one of a correction or a compensation of at least one of a shim, B0 drift, a combination of rotation, translation shim and drift associated with the object, wherein the at least one of the correction or the compensation is performed based on the first data, the second data and deviations of at least one of the first data or the second data.

32. A method for producing an image of an object with a magnetic resonance imaging (MRI) system, comprising:

a) acquiring a map of the object by repeatedly performing a navigator pulse sequence with the MRI system to obtain a plurality of navigator signals and in which each navigator signal samples k-space along a navigator path oriented at a different angle;

b) acquiring a k-space image data set by performing a scan of the object by repeatedly performing an imaging pulse sequence with the MRI system;

c) acquiring navigator k-space data with the MRI system during the performance of the scan in step b) by interleaving the performance of the navigator pulse sequence with the performance of the imaging pulse sequence;

d) altering the k-space image data acquired in step b) by comparing the acquired navigator k-space data with the acquired map to determine the alteration; and

e) reconstructing an image with the k-space image data altered in step d).

33. The method of claim 32, wherein the k-space navigator path includes:

three orthogonal straight line segments that pass through the center of k-space, and

three orthogonal 90°

arcuate segments.

34. The method of claim 32, wherein the k-space is altered in step d) after the k-space image data is acquired.

35. The method of claim 32, wherein the k-space is altered in step d) by altering the imaging pulse sequence used to acquire the k-space image data.

36. The method of claim 32, wherein the comparison in step d) comprises substeps of:

i) determining the translation of the object along the axes defined by each of the three orthogonal straight line segments, and

ii) determining the rotation of the object about the axes defined by each of the three orthogonal arcuate segments.

37. The method of claim 36, wherein the translation and the rotation are determined by matching the acquired k-space navigator data with the navigator signals in the acquired map.

38. The method of claim 32, further comprising:

(f) combining the imaging pulse sequence used in step b) and the navigator pulse sequence used in step c) into a single pulse sequence by;

i) producing an radio frequency (RF) excitation pulse,

ii) performing an image data readout kernel in which prescribed imaging gradients are produced and the k-space image data are acquired, and

iii) performing a navigator data readout kernel in which k-space navigator data along the k-space navigator path are acquired.

39. The method of claim 38, wherein the k-space navigator path includes:

i) three orthogonal straight line segments that pass through the center of k-space, and

ii) three orthogonal 90°

arcuate segments.

40. The method of claim 38, wherein the alterations in step d) are made by altering the image data readout kernel.

41. The method of claim 38, wherein the image data readout kernel precedes the navigator data readout kernel and further comprising:

(g) altering the navigator data readout kernel as a function of the magnitude of a phase encoding gradient produced during the image data readout kernel.

42. The method of claim 41, wherein step a) includes acquiring additional map data over a range of phase encoding gradient magnitudes, and wherein step f) includes calculating the alteration of the navigator data readout kernel using the additional map data.

43. The method of claim 32, further comprising detecting changes in a polarizing magnetic field B₀ during the scan, and altering the navigator pulse sequence to offset effects attributable to the changes.

44. The method of claim 43, wherein the changes in the polarizing magnetic field B₀ include changes in a shim caused by a motion of the object.

45. The method of claim 43, wherein the changes in the polarizing magnetic field B₀ include changes in a magnitude of the magnetic field caused by a drift.

46. The method of claim 43, wherein the changes are detected by comparing k-space navigator data with the map acquired in step a).

47. The method of claim 32, wherein the MRI system includes a plurality of receive coils, and wherein the signals produced by the receive coils during the performance of the navigator pulse sequence are combined to form the acquired navigator signal that samples k-space along a path of the navigator.

48. The method of claim 47, wherein the receive coil signals are combined in a first configuration to provide a first acquired navigator signal that is used in step d) to determine a translation of the object, and wherein the receive coil signals are combined in a second configuration to provide a second acquired navigator signal that is used in step d) to determine a rotation of the object.

49. A software arrangement provided for producing an image of an object with a magnetic resonance imaging (MRI) system, comprising:

a first module programmed to acquire a map of the object by repeatedly performing a navigator pulse sequence with the MRI system to obtain a plurality of navigator signals and in which each navigator signal samples k-space along a navigator path oriented at a different angle;

a second module programmed to acquire a k-space image data set by performing a scan of the object by repeatedly performing an imaging pulse sequence with the MRI system;

a third module programmed to acquire navigator k-space data with the MRI system during the performance of the scan using the second module by interleaving the performance of the navigator pulse sequence with the performance of the imaging pulse sequence;

a fourth module programmed to alter the k-space image data acquired using the second module by comparing the acquired navigator k-space data with the acquired map to determine the alteration; and

a fifth module programmed to reconstruct an image with the k-space image data altered using the fourth module.

50. A system for producing an image of an object with a magnetic resonance imaging (MRI) system, comprising:

a processor configured to;

(a) acquire a map of the object by repeatedly performing a navigator pulse sequence with the MRI system to obtain a plurality of navigator signals and in which each navigator signal samples k-space along a navigator path oriented at a different angle;

(b) acquire a k-space image data set by performing a scan of the object by repeatedly performing an imaging pulse sequence with the MRI system;

(c) acquire navigator k-space data with the MRI system during the performance of the scan in procedure b) by interleaving the performance of the navigator pulse sequence with the performance of the imaging pulse sequence;

(d) alter the k-space image data acquired in procedure b) by comparing the acquired navigator k-space data with the acquired map to determine the alteration; and

(e) reconstruct an image with the k-space image data altered in procedure d).

51. A computer-accessible medium which includes and facilitates an execution of a set of instructions that are provided for producing an image of an object with a magnetic resonance imaging (MRI) system, wherein when a processing arrangement executes the instructions, the processing arrangement executes the steps comprising:

a) acquiring a map of the object by repeatedly performing a navigator pulse sequence with the MRI system to obtain a plurality of navigator signals and in which each navigator signal samples k-space along a navigator path oriented at a different angle;

b) acquiring a k-space image data set by performing a scan of the object by repeatedly performing an imaging pulse sequence with the MRI system;

c) acquiring navigator k-space data with the MRI system during the performance of the scan in step b) by interleaving the performance of the navigator pulse sequence with the performance of the imaging pulse sequence;

d) altering the k-space image data acquired in step b) by comparing the acquired navigator k-space data with the acquired map to determine the alteration; and

e) reconstructing an image with the k-space image data altered in step d).