Method and apparatus for registration of an atlas to an image

• US 20090220171A1
• Filed: 05/02/2006
• Published: 09/03/2009
• Est. Priority Date: 05/02/2005
• Status: Active Grant

• Current Assignee: Agency For Science Technology and Research (Government of Singapore)
• Original Assignee: Agency For Science Technology and Research (Government of Singapore)
• Inventors: Nowinski, Wieslaw Lucjan, Liu, Jimin, Huang, Su
• Granted Patent: US 8,687,917 B2
• Time in Patent Office: Days
• US Class Current: 382/282
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 6/501 for diagnosis of the head, e.g. neuroimaging or craniography
• CPC Class Codes: A61B 6/5247 combining images from an ionising-radiation diagnostic technique and a non-ionising radiation diagnostic technique, e.g. X-ray and ultrasound
• CPC Class Codes: G06T 2207/30016 Brain
• CPC Class Codes: G06T 7/33 using feature-based methods
• CPC Class Codes: G06V 10/754 involving a deformation of the sample pattern or of the reference pattern; Elastic matching
• CPC Class Codes: G06V 20/653 by matching three-dimensional models, e.g. conformal mapping of Riemann surfaces

Abstract

A method (100) and an apparatus (200) are disclosed for registering an input image and an atlas. The atlas is warped (130) using non-rigid registration. In particular, boundary displacements of structures in the atlas are calculated (132) which register those structures with equivalent structures in the input image. The boundaries of structures in the atlas are then warped (133) according to their respective boundary displacements using topology preserving propagation of boundary points of the structures.

Claims

1. A method of registering a first image with a second image, said method comprising the steps of:

calculating a boundary displacement of at least one structure in said first image in order to register that structure with an equivalent structure in said second image; and

warping the boundary of said structure in said first image according to said boundary displacement using topology preserving propagation of boundary points of said structure.

2. The method according to claim 1, wherein said first and second images are defined in a predefined domain, and said calculating step comprises the sub-steps of:

dividing said domain into blocks;

calculating a displacement of the centre points of each block, said displacement maximising a block similarity measure between corresponding blocks in said first and second images; and

calculating said boundary displacement by calculating a displacement for points on said boundary of said structure by interpolating said displacements of neighbouring centre points.

3. The method according to claim 2 wherein said first and second images are volumetric images, and said blocks are hexahedrons.

4. The method according to claim 1 wherein said topology preserving propagation of boundary points comprises adding points to and removing points from the boundary of said structure.

5. The method according to claim 4 wherein only points not belonging to other structures are added to said structure.

6. An apparatus for registering a first image with a second image, said apparatus comprising:

means for calculating a boundary displacement of at least one structure in said first image in order to register that structure with an equivalent structure in said second image; and

means for warping the boundary of said structure in said first image according to said boundary displacement using topology preserving propagation of boundary points of said structure.

7. The apparatus according to claim 6, wherein said first and second images are defined in a predefined domain, and said means for calculating comprises:

means for dividing said domain into blocks;

means for calculating a displacement of the centre points of each block, said displacement maximising a block similarity measure between corresponding blocks in said first and second images; and

means for calculating said boundary displacement by calculating a displacement for points on said boundary of said structure by interpolating said displacements of neighbouring centre points.

8. The apparatus according to claim 7 wherein said first and second images are volumetric images, and said blocks are hexahedrons.

9. The apparatus according to claim 6 wherein said topology preserving propagation of boundary points comprises adding points to and removing points from the boundary of said structure.

10. The apparatus according to claim 9 wherein only points not belonging to other structures are added to said structure.

11. A computer program product including a computer readable medium having recorded thereon a computer program for registering a first image with a second image, said program comprising:

code for calculating a boundary displacement of at least one structure in said first image in order to register that structure with an equivalent structure in said second image; and

code for warping the boundary of said structure in said first image according to said boundary displacement using topology preserving propagation of boundary points of said structure.

12. The computer program product according to claim 11, wherein said first and second images are defined in a predefined domain, and said code for calculating comprises:

code for dividing said domain into blocks;

code for calculating a displacement of the centre points of each block, said displacement maximising a block similarity measure between corresponding blocks in said first and second images; and

code for calculating said boundary displacement by calculating a displacement for points on said boundary of said structure by interpolating said displacements of neighbouring centre points.

13. The computer program product according to claim 12 wherein said first and second images are volumetric images, and said blocks are hexahedrons.

14. The computer program product according to claim 11 wherein said topology preserving propagation of boundary points comprises adding points to and removing points from the boundary of said structure.

15. The computer program product according to claim 14 wherein only points not belonging to other structures are added to said structure.