Systems and methods for processing x-ray images

• US 7,620,146 B2
• Filed: 11/06/2006
• Issued: 11/17/2009
• Est. Priority Date: 10/23/1998
• Status: Expired due to Fees

• Current Assignee: Varian Medical Systems Incorporated (Siemens AG)
• Original Assignee: Varian Medical Systems Incorporated (Siemens AG)
• Inventors: Mostafavi, Hassan
• Primary Examiner(s): SONG, HOON K
• Application Number:
  US11/593,950
• Publication Number:
  US 20070053494A1
• Time in Patent Office: 1,107 Days
• Field of Search: 378/62, 378/5, 378/94, 378/95, 378/98, 378/98.11, 378/98.12, 382/157, 382/128, 382/159, 382/132
• US Class Current: 378/62
• CPC Class Codes: A61B 5/7289 Retrospective gating, i.e. associating measured signals or images with a physiological event after the actual measurement or image acquisition, e.g. by simultaneously recording an additional physiological signal during the measurement or image acquisition
• CPC Class Codes: A61B 6/4441 the rigid structure being a C-arm or U-arm
• CPC Class Codes: A61B 6/469 for selecting a region of interest [ROI]
• CPC Class Codes: A61B 6/5235 combining images from the same or different ionising radiation imaging techniques, e.g. PET and CT
• CPC Class Codes: A61B 6/5288 involving retrospective matching to a physiological signal
• CPC Class Codes: A61B 6/541 involving acquisition triggered by a physiological signal
• CPC Class Codes: A61N 2005/1061 using an x-ray imaging system having a separate imaging source
• CPC Class Codes: A61N 5/1037 taking into account the movement of the target, e.g. 4D-image based planning
• CPC Class Codes: A61N 5/1049 for verifying the position of the patient with respect to the radiation beam
• CPC Class Codes: A61N 5/1064 for adjusting radiation treatment in response to monitoring
• CPC Class Codes: G06T 17/00 Three dimensional [3D] modelling, e.g. data description of 3D objects
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction

Abstract

A method for processing x-ray images includes collecting a first x-ray image and a second x-ray image, determining a composite image based on the first and second x-ray images, collecting a third x-ray image, and adjusting the third x-ray image based on the composite image. Another method of processing x-ray images includes obtaining a first x-ray image, obtaining a second x-ray image, and determining a composite image based on at least a portion of the first and second x-ray images.

Claims

1. A method of processing an x-ray image, at least part of the method implemented using a processor, the method comprising:

obtaining a first x-ray image and a second x-ray image in a session, wherein the first and the second x-ray images are obtained using respective x-ray radiation having a same energy level, and at least a portion of the first x-ray image and at least a portion of the second x-ray image comprise respective images of a same portion of an object;

determining a composite image based at least in part on the at least a portion of the first x-ray image and the at least a portion of the second x-ray image, wherein one of the first and second x-ray images is a real-time input for determining the composite image; and

using the composite image to determine whether the object has moved; and

at least one of storing the composite image in a medium, displaying the composite image, and adjusting a system component based at least in part on the composite image.

2. The method of claim 1, wherein the first and second x-ray images each contains an image of at least a portion of an animal body.

3. The method of claim 1, wherein the determining the composite image comprises subtracting the at least a portion of the first x-ray image from the at least a portion of the second x-ray image.

4. The method of claim 1, further comprising determining a value associated with a contrast of the composite image.

5. The method of claim 1, wherein the act of determining whether the object has moved does not involve determining a magnitude of a movement by the object.

6. The method of claim 1, further comprising comparing the composite image to a reference image.

7. The method of claim 6, wherein the reference image is a portion of a volumetric image.

8. The method of claim 6, further comprising determining a position of at least a portion of the object based on a result of the act of comparing.

9. The method of claim 1, wherein the first and the second x-ray images are generated at approximately a same phase of a physiological cycle.

10. A system for processing an x-ray image, comprising:

an x-ray source;

a detector for generating a first x-ray image and a second x-ray image in a session using respective x-ray radiation generated by the x-ray source, the respective x-ray radiation having a same energy level, wherein at least a portion of the first x-ray image and at least a portion of the second x-ray image comprise respective images of a same portion of an object; and

a processor configured for determining a composite image based at least in part on the at least a portion of the first x-ray image and the at least a portion of the second x-ray image, wherein one of the first and second x-ray images is a real-time input for determining the composite image, wherein the processor is also configured for using the composite image to determine whether the object has moved.

11. The system of claim 10, wherein the first and second x-ray images each contains an image of at least a portion of an animal body.

12. The system of claim 10, wherein the processor is configured to subtract the at least a portion of the first x-ray image from the at least a portion of the second x-ray image.

13. The system of claim 10, wherein the processor is configured to determine a value associated with a contrast of the composite image.

14. The system of claim 10, wherein the processor determines whether the object has moved without determining a magnitude of a movement by the object.

15. The system of claim 10, wherein the processor is further configured to compare the composite image to a reference image.

16. The system of claim 15, wherein the reference image is a portion of a volumetric image.

17. The system of claim 15, wherein the processor is further configured to determine a position of at least a portion of the object based on a result of the act of comparing.

18. The system of claim 10, wherein the first and the second images are generated at approximately a same phase of a physiological cycle.

19. A computer readable medium having a set of stored instructions, the execution of which causes a process to be performed, the process comprising:

obtaining a first x-ray image and a second x-ray image in a procedure, wherein the first and the second x-ray images are obtained using respective x-ray radiation having a same energy level, and at least a portion of the first x-ray image and at least a portion of the second x-ray image comprise respective images of a same portion of an object;

determining a composite image based at least in part on the at least a portion of the first x-ray image and the at least a portion of the second x-ray image, wherein one of the first and second x-ray images is a real-time input for determining the composite image; and

using the composite image to determine whether the object has moved; and

at least one of storing the composite image in a medium, displaying the composite image, and adjusting a system component based at least in part on the composite image.

20. The computer readable medium of claim 19, wherein the process further comprises comparing the composite image to a portion of a volumetric image.

21. A method of processing x-ray images, at least part of the method implemented using a processor, the method comprising:

obtaining N x-ray images that are generated in a sequence using a same energy level, wherein N>

2;

determining an average image using at least a subset of the N x-ray images;

determining an enhanced image for the Nth x-ray image by subtracting the average image from the Nth x-ray image, wherein one of the N x-ray images is a real-time input for determining the enhanced image, and wherein the N x-ray images are obtained using radiation; and

at least one of storing the enhanced image in a medium, displaying the enhanced image, and adjusting a system component based at least in part on the enhanced image.

22. The method of claim 21, further comprising using the enhanced image to determine whether an object has moved.

23. The method of claim 21, wherein two of the N-x-ray images comprise respective images of a same portion of an object.

24. A system for processing x-ray images, comprising:

a processor configured to obtain N x-ray images, determine an average image using at least a subset of the N x-ray images, and determine an enhanced image for the Nth x-ray image by subtracting the average image from the Nth x-ray image, wherein one of the N x-ray images is a real-time input for determining the enhanced image, and wherein the N x-ray images are obtained using radiation, wherein N>

2, and the N x-ray images are generated in a sequence using a same energy level.

25. The system of claim 24, wherein the processor is further configured to use the enhanced image to determine whether an object has moved.

26. The system of claim 24, wherein two of the N-x-ray images comprise respective images of a same portion of an object.

27. A computer readable medium having a set of stored instructions, the execution of which causes a process to be performed, the process comprising:

obtaining N x-ray images that are generated in a sequence using a same energy level, wherein N>

2;

determining an average image using at least a subset of the N x-ray images;

determining an enhanced image for the Nth x-ray image by subtracting the average image from the Nth x-ray image, wherein one of the N x-ray images is a real-time input for determining the enhanced image, and wherein the N x-ray images are obtained using radiation; and

at least one of storing the enhanced image in a medium, displaying the enhanced image, and adjusting a system component based at least in part on the enhanced image.

28. The computer readable medium of claim 27, wherein the process further comprises using the enhanced image to determine whether an object has moved.

29. The computer readable medium of claim 27, wherein two of the N-x-ray images comprise respective images of a same portion of an object.