Interactive manual deformable registration of images

• US 8,165,425 B2
• Filed: 07/24/2008
• Issued: 04/24/2012
• Est. Priority Date: 07/24/2008
• Status: Active Grant

• Current Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Original Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Inventors: DeClerck, Jerome
• Primary Examiner(s): Perungavoor, Sath V
• Assistant Examiner(s): HEIDEMANN, JASON E
• Application Number:
  US12/179,224
• Publication Number:
  US 20100021082A1
• Time in Patent Office: 1,370 Days
• Field of Search: None
• US Class Current: 382/294
• CPC Class Codes: G06T 1/00 General purpose image data processing
• CPC Class Codes: G06T 2207/10088 Magnetic resonance imaging [MRI]
• CPC Class Codes: G06T 2207/10104 Positron emission tomography [PET]
• CPC Class Codes: G06T 2207/20092 Interactive image processing based on input by user
• CPC Class Codes: G06T 2207/30004 Biomedical image processing
• CPC Class Codes: G06T 7/33 using feature-based methods

Abstract

An image processing method is described that allows a user to deform an overlay image for the purpose of registration with a source image. The user defines a stretch vector for example by ‘clicking and dragging’ a mouse pointer and an algorithm deforms the overlay image according to a linear interpolated roll-off function.

Claims

1. A method of deforming an overlay image for registration with a source image, said method comprising the steps of:

(i) defining a vector d in the source image

(ii) determining the inverse vector −

d;

(iii) calculating a linear interpolated displacement field whereby each point is displaced in a direction parallel with −

d by a distance determined by a roll-off function, g, said function having a value that decreases continuously with distance in any direction, from a value of one at the origin of −

d, to a value of substantially zero at some point at a distance R to the origin of where the displacement d is defined, and

(iv) applying the linear interpolated displacement field to recalculate the overlay image.

2. A method according to claim 1, further including the steps of:

defining a vector D in the source image;

defining a set of vectors d1, d2, . . . , dn such that

3. A method according to claim 2, where the overlay is recalculated n times, applying a linear interpolated displacement field calculated from one of

d1, d2, . . . , dn each time.

4. A method according to claim 2, where the overlay is recalculated by combining the linear interpolated displacement fields calculated from each of

d1, d2, . . . , dn and applying the resultant combination to the overlay.

5. A method according to claim 4, where at least one of the combining the displacement fields and the recalculation of the overlay is effected by adding field values at the nodes of the respective fields.

6. A method according to claim 4, where at least one of the combining the displacement fields and the recalculation of the overlay is effected by composition of the respective fields.

7. A method according to claim 1, where g′

, the first derivative of g with respect to distance x from the origin on where the displacement d is defined is substantially zero at the boundary of the field.

8. A method according to claim 1, where g′

is zero at the origin of −

d.

9. A method according to claim 1, where g′

is a continuous function.

10. A method according to claim 9, where g″

, the second derivative of g with respect to distance from the origin on where the displacement d is defined, is a continuous function.

11. A method according to claim 1, where the deformation obtained by applying the displacement field to an image is invertible.

12. A method according to claim 1, further including the step of defining R.

13. A method according to claim 12, where the function x+∥

d∥

.g(x/R) has non-negative derivative with respect to distance from the origin of −

d.

14. A method according to claim 13 where X+∥

d∥

.g(x/R) is greater than α

, where α

is an arbitrary strictly positive value between 0 and 1.