Model-based registration of cardiac CTA and MR acquisitions

• US 6,563,941 B1
• Filed: 12/14/1999
• Issued: 05/13/2003
• Est. Priority Date: 12/14/1999
• Status: Active Grant

• Current Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Original Assignee: Siemens Corporate Research Incorporated (Siemens AG)
• Inventors: Aharon, Schmuel, Gupta, Alok, OʼDonnell, Thomas
• Primary Examiner(s): Werner, Brian
• Assistant Examiner(s): Miller, Ryan J.
• Application Number:
  US09/460,746
• Time in Patent Office: 1,246 Days
• Field of Search: 382/131, 382/154, 382/289, 382/294, 345/427, 378/4, 378/21, 600/425
• US Class Current: 382/131
• CPC Class Codes: G06T 2207/30004 Biomedical image processing
• CPC Class Codes: G06T 3/4061 by injecting details from different spectral ranges
• CPC Class Codes: G06T 7/33 using feature-based methods
• CPC Class Codes: G06T 7/38 Registration of image sequences

Abstract

A method for registration of magnetic resonance (MR) and computed topography (CT) images, in accordance with the present invention includes providing MR images having a region of interest delineated by first contours and providing CT images having the region of interest delineated by second contours. A pre-existing model of the region of interest is also provided. The pre-existing model is fit to the first contours or the second contours to provide a first resultant model. The first resultant model is then copied to provide a copied model. The copied model is fit to the other of the first contours and the second contours to provide a second resultant model. By rotating and translating the first resultant model and the second resultant model, the first resultant model and the second resultant model are registered. The rotation and translation information are stored and applied to the images to provide registration between the MR images and the CT image

Claims

1. A method for registration of magnetic resonance (MR) and computed topography (CT) images comprising the steps of:

providing MR images having a region of interest delineated by first contours;

providing CT images having the region of interest delineated by second contours;

providing a pre-existing model of the region of interest, the model representing an anatomical structure of interest;

fitting the pre-existing model to one of the first contours and the second contours to provide a first resultant model;

copying the first resultant model to provide a copied model;

fitting the copied model to the other of the first contours and the second contours to provide a second resultant model;

rotating and translating one of the first resultant model and the second resultant model to register the first resultant model and the second resultant model;

storing rotation and translation information; and

applying the rotation and translation information to the images to provide registration between the MR images and the CT images.

2. The method as recited in claim 1, wherein the step of providing MR images having a region of interest delineated by first contours includes the step of providing MR images from a plurality of positions.

3. The method as recited in claim 1, wherein the step of providing MR images having a region of interest delineated by first contours includes the step of manually delineating the region of interest.

4. The method as recited in claim 1, wherein the step of providing MR images having a region of interest delineated by first contours includes the step of automatically delineating the region of interest by employing a segmentation algorithm.

5. The method as recited in claim 1, wherein the step of providing CT images having the region of interest delineated by second contours includes the step of manually delineating the region of interest.

6. The method as recited in claim 1, wherein the step of providing CT images having the region of interest delineated by second contours includes the step of automatically delineating the region of interest by employing a segmentation algorithm.

7. The method as recited in claim 1, wherein the MR images and CT images are acquired of a beating heart.

8. The method as recited in claim 7, wherein the CT images are acquired at a rate of greater than or equal to 8 images per second.

9. The method as recited in claim 1, wherein the step of fitting the pre-existing model to one of the first contours and the second contours to provide a first resultant model includes the steps of:

rigidly translating and rotating the pre-existing model;

adjusting global shape parameters of the pre-existing model; and

conforming a mesh of springs of the pre-existing model to accommodate individual features described by one of the first and second contours.

10. The method as recited in claim 1, wherein the step of fitting the copied model includes the steps of:

rigidly translating and rotating the copied model;

adjusting global shape parameters of the copied model; and

conforming a mesh of springs of the copied model to accommodate individual features described by the other of the first and second contours.

11. The method as recited in claim 1, further comprising the step of determining volumes of features in the MR and CT images by summing voxels in the first and second resultant models, respectively.

12. A method for registration of magnetic resonance (MR) and computed topography (CT) images comprising the steps of:

providing MR and CT images of a heart;

delineating an epicardial surface and an endocardial surface of the heart in the MR and CT images by designating contours on the images;

providing a pre-existing heart model;

fitting the pre-existing heart model to the contours in the MR images to provide an MR model;

copying the MR model to provide a copied MR model;

fitting the copied MR model to contours in the CT images to provide a CT model;

rotating and translating one of the MR model and the CT model to register the MR model and the CT model;

storing rotation and translation information; and

applying the rotation and translation information to the MR and CT images to provide registration between the MR images and the CT images.

13. The method as recited in claim 12, wherein the step of delineating an epicardial surface and an endocardial surface of the heart includes the step of manually delineating the epicardial surface and the endocardial surface.

14. The method as recited in claim 12, wherein the step of delineating an epicardial surface and an endocardial surface of the heart includes the step of automatically delineating the epicardial surface and the endocardial surface by employing a segmentation algorithm.

15. The method as recited in claim 12, wherein the CT images are acquired at a rate of greater than or equal to 8 images per second.

16. The method as recited in claim 12, wherein the step of fitting the pre-existing model to the contours of the MR images includes the steps of:

rigidly translating and rotating the pre-existing model;

adjusting global shape parameters of the pre-existing model; and

conforming a mesh of springs of the pre-existing model to accommodate individual features described by the contours in the MR images.

17. The method as recited in claim 12, wherein the step of fitting the copied MR model to the contours of the CT images includes the steps of:

rigidly translating and rotating the copied MR model;

adjusting global shape parameters of the copied MR model; and

conforming a mesh of springs of the copied MR model to accommodate individual features described by the contours in the CT images.

18. The method as recited in claim 12, further comprising the step of determining volumes of a left ventricle blood pool and myocardium in the MR and CT images by summing voxels in the MR and CT models, respectively.

19. A program storage device readable by machine, tangibly embodying a program of instructions executable by the machine to perform method steps for registration of magnetic resonance (MR) and computed topography (CT) images, the method steps comprising:

providing MR and CT images of a heart;

delineating an epicardial surface and an endocardial surface of the heart in the MR and CT images by designating contours on the images;

providing a pre-existing heart model;

fitting the pre-existing heart model to the contours in the MR images to provide an MR model;

copying the MR model to provide a copied MR model;

fitting the copied MR model to contours in the CT images to provide a CT model;

rotating and translating one of the MR model and the CT model to register the MR model and the CT model;

storing rotation and translation information; and

applying the rotation and translation information to the MR and CT images to provide registration between the MR images and the CT images.

20. The program storage device as recited in claim 19, wherein the step of delineating an epicardial surface and an endocardial surface of the heart includes the step of manually delineating the epicardial surface and the endocardial surface.

21. The program storage device as recited in claim 19, wherein the step of delineating an epicardial surface and an endocardial surface of the heart includes the step of automatically delineating the epicardial surface and the endocardial surface by employing a segmentation algorithm.

22. The program storage device as recited in claim 19, wherein the CT images are acquired at a rate of greater than or equal to 8 images per second.

23. The program storage device as recited in claim 19, wherein the step of fitting the pre-existing model to the contours of the MR images includes the steps of:

rigidly translating and rotating the pre-existing model;

adjusting global shape parameters of the pre-existing model; and

conforming a mesh of springs of the pre-existing model to accommodate individual features described by the contours in the MR images.

24. The program storage device as recited in claim 19, wherein the step of fitting the copied MR model to the contours of the CT images includes the steps of:

rigidly translating and rotating the copied MR model;

adjusting global shape parameters of the copied MR model; and

conforming a mesh of springs of the copied MR model to accommodate individual features described by the contours in the CT images.

25. The program storage device as recited in claim 19, further comprising the step of determining volumes in the MR and CT images by employing voxels in the MR and CT models, respectively.

26. A system for registration of magnetic resonance (MR) and computed topography (CT) images, comprising:

means for delineating an epicardial surface and an endocardial surface of a heart in MR and CT images by designating contours on the images;

a pre-existing heart model for fitting to the contours in the MR images to provide an MR model;

means for copying the MR model to provide a copied MR model, the copied MR model for fitting to contours in the CT images to provide a CT model;

means for rotating and translating the MR model and the CT model to register the MR model and the CT model;

a memory for storing rotation and translation information such that the rotation and translation information is applied to the MR and CT images to provide registration between the MR images and the CT images; and

a display for viewing the registered MR images and CT images.

27. The system as recited in claim 26, wherein the means for delineating includes a mouse and a graphical user interface.

28. The system as recited in claim 26, wherein the means for copying includes a processor.

29. The system as recited in claim 26, wherein the means for rotating and translating includes a processor.

30. The system as recited in claim 26, wherein the pre-existing model includes a mesh of springs to accommodate individual features described by the contours in the MR images.

31. The system as recited in claim 26, wherein the copied MR model includes a mesh of springs of the copied MR model to accommodate individual features described by the contours in the CT images.

32. The system as recited in claim 26, wherein the MR and CT models include voxels for determining volumes in the MR and CT images.