Methods and apparatus for image reconstruction

• US 7,734,079 B2
• Filed: 06/22/2005
• Issued: 06/08/2010
• Est. Priority Date: 09/28/2004
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Sopcak, Zachary William, Conry, Anne Marie, Grekowicz, Brian, Seidenschnur, George, Hsieh, Jiang, Dong, Fang Frank, Myers, Thomas John
• Primary Examiner(s): Ahmed; Samir A
• Assistant Examiner(s): TSAI, TSUNG YIN
• Application Number:
  US11/158,611
• Publication Number:
  US 20060078185A1
• Time in Patent Office: 1,812 Days
• Field of Search: 382/131
• US Class Current: 382/131
• CPC Class Codes: A61B 6/027 characterised by the use of a particular data acquisition trajectory, e.g. helical or spiral
• CPC Class Codes: G06T 11/006 Inverse problem, transformation from projection-space into object-space, e.g. transform methods, back-projection, algebraic methods

Abstract

Methods and apparatus for producing an image of an object with a multi-slice imaging apparatus having a row of detectors are provided. The method includes generating a first partial image using projection data acquired at a first imaging position in a step-and-shoot imaging mode, generating a second partial image using projection data acquired at a second imaging position, and combining the partial images to form a final image.

Claims

1. A method for producing an image of an object with a multi-slice imaging apparatus, said method comprising:

generating a first partial image using projection data acquired at a first imaging position in a step-and-shoot imaging mode, wherein the first projection data is weighted using;

2. The method in accordance with claim 1 wherein the first and the second imaging positions are axially adjacent.

3. The method in accordance with claim 1 wherein combining the partial images comprises combining the partial images that have been weighted to account for an axial distance between the detector and an axial location of the final image.

4. The method in accordance with claim 1 further comprising generating an image between detector row locations by interpolating a set of projections acquired at the corresponding locations.

5. The method in accordance with claim 4 further comprising interpolating a set of projections acquired at the corresponding locations using:

6. The method in accordance with claim 1 further comprising interpolating between the images to form a final image using:

7. A method in accordance with claim 1 wherein the second partial image is consecutive and non-overlapping with the first partial image.

8. A method in accordance with claim 1 further comprising interpolating projection data for an area outside a boundary of the partial images to form the final image.

9. A method for producing an image of an object with a multi-slice imaging apparatus, said method comprising:

generating a first partial image using projection data acquired at a first single imaging position in a step-and-shoot imaging mode;

generating a second partial image using projection data acquired at a second single imaging position, wherein the second projection data is weighted using;

10. A computed tomographic (CT) imaging system for reconstructing an image of an object, said imaging system comprising:

a detector array;

at least one radiation source; and

a computer coupled to said detector array and said radiation source, said computer configured to;

generate a first partial image using projection data acquired at a first imaging position in a step-and-shoot imaging mode, wherein the first projection data partial image is weighted using;

11. The computed tomographic (CT) imaging system in accordance with claim 10 wherein said computer is further configured to weight the partial images to account for an axial distance between the detector and an axial location of the final image.

12. The computed tomographic (CT) imaging system in accordance with claim 10 wherein the first and the second axial imaging positions are axially adjacent.

13. The computed tomographic (CT) imaging system in accordance with claim 10 wherein the second partial image is weighted using:

14. The computed tomographic (CT) imaging system in accordance with claim 10 wherein said computer is further configured to generate an image between detector row locations by interpolating a set of projections acquired at the corresponding locations.

15. The computed tomographic (CT) imaging system in accordance with claim 14 wherein said computer is further configured to interpolate a set of projections acquired at the corresponding locations using:

16. The computed tomographic (CT) imaging system in accordance with claim 10 wherein said computer is further configured to interpolate between the images using:

17. A CT imaging system in accordance with claim 10 wherein said computer is further configured to:

backproject the adjacent axial scans; and

filter the backprojected scans.

18. A computer readable medium encoded with a program code segment executable by a computer for reconstructing an image of an object, said segment programmed to instruct the computer to:

generate a first partial image using projection data acquired at a first imaging position in a step-and-shoot imaging mode wherein the first partial image is weighted using;

19. The computer readable medium in accordance with claim 18 wherein the first and the second imaging positions are axially adjacent.

20. The computer readable medium in accordance with claim 18 wherein said program code segment is further programmed to combine the partial images that have been weighted to account for an axial distance between the detector and an axial location of the final image.

21. The computer readable medium in accordance with claim 18 wherein the second partial image is weighted using:

22. The computer readable medium in accordance with claim 18 wherein said program code segment is further programmed to generate an image between detector row locations by interpolating a set of projections acquired at the corresponding locations.

23. The computer readable medium in accordance with claim 18 wherein said program code segment is further programmed to interpolate a set of projections acquired at the corresponding locations using:

24. The computer readable medium in accordance with claim 18 wherein said program code segment is further programmed to interpolate between the images using:

25. The computer readable medium in accordance with claim 18 wherein the second partial image is consecutive and non-overlapping with the first partial image.

26. The computer readable medium in accordance with claim 18 wherein said program code segment is further programmed to interpolate projection data for an area outside a boundary of the partial images to form the final image.