Motion correction of magnetic resonance images

• US 6,518,759 B2
• Filed: 04/09/2001
• Issued: 02/11/2003
• Est. Priority Date: 04/09/2001
• Status: Expired due to Term

• Current Assignee: Mayo Foundation For Medical Education And Research (Mayo Clinic)
• Original Assignee: Mayo Foundation For Medical Education And Research (Mayo Clinic)
• Inventors: Bernstein, Matthew A.
• Primary Examiner(s): Lefkowitz, Edward
• Assistant Examiner(s): Vargas, Dixomara
• Application Number:
  US09/829,238
• Publication Number:
  US 20020190714A1
• Time in Patent Office: 673 Days
• Field of Search: 324/318, 324/307, 324/309
• US Class Current: 324/307
• CPC Class Codes: G01R 33/54 Signal processing systems, e.g. using pulse sequences ; Generation or control of pulse sequences; Operator console

Abstract

A CE-MIRA image is acquired using a centric view order. The acquired k-space data set is motion corrected by reconstructing tracking images from successive annular segments of k-space data and detecting the location of a point spread object therein. Each k-space data segment is phase corrected to align the point spread object with a reference position.

Claims

1. A method for acquiring a motion corrected image with a magnetic resonance imaging (MRI) system, the steps comprising:

a) acquiring a k-space data set by repeating an imaging pulse sequence with the MRI system to sample k-space as a series of k-space segments;

b) reconstructing a series of tracking images from the corresponding series of acquired k-space segments;

c) calculating the movement of point objects in the subject during the acquisition of each k-space segment by detecting the movement of corresponding point spread objects in each tracking image;

d) calculating a corrective phase shift for each k-space segment based on the detected movement during the acquisition of each k-space segment; and

e) reconstructing an image using the corrected k-space segments.

2. The method as recited in claim 1 in which each k-space segment includes k-space samples from an annular region around the origin of k-space.

3. The method as recited in claim 1 in which step a) is performed with a centric view order.

4. The method as recited in claim 1 in which step a) is performed with a reverse centric view order.

5. The method as recited in claim 1 in which step c) is performed by:

i) selecting one of the tracking images as a reference image; and

ii) determining the amount of the motion-induced mis-registration between each tracking image and the reference image by finding the peak of the cross-correlation function of each tracking image with the reference image.

6. The method as recited in claim 1 in which a three-dimensional imaging pulse sequence is used in step a) which has a readout gradient axis and two phase encoding gradient axes, and the k-space segments are defined by the values of two phase encoding gradients which sample k-space at points along two orthogonal axes in k-space.

7. The method as recited in claim 6 in which step a) is performed by using a centric view order that samples k-space defined by the two orthogonal axes as a k-space segment at the center of k-space and a series of ring k-space segments that surround the central k-space segment.

8. The method as recited in claim 7 in which step c) is performed by:

i) selecting one of the tracking images as a reference image; and

ii) determining the amount of the motion-induced mis-registration between each tracking image and the reference image by finding the peak of the cross-correlation function of each tracking image with the reference image.

9. The method as recited in claim 6 in which the image is acquired from a living subject and the steps also include:

injecting the living subject with a contrast agent to enhance NMR signals acquired from small anatomic structures; and

employing the small anatomic structures as the point objects in step c).

10. The method as recited in claim 9 in which the small anatomic structures are blood vessels.