EKG-less cardiac image reconstruction

• US 6,434,215 B1
• Filed: 06/28/2001
• Issued: 08/13/2002
• Est. Priority Date: 06/28/2001
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Cesmeli, Erdogan
• Primary Examiner(s): Bruce, David V.
• Assistant Examiner(s): Hobden, Pamela R.
• Application Number:
  US09/681,943
• Time in Patent Office: 411 Days
• Field of Search: 378/4, 378/19, 378/20
• US Class Current: 378/8
• CPC Class Codes: A61B 6/027 characterised by the use of a particular data acquisition trajectory, e.g. helical or spiral
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/5217 extracting a diagnostic or physiological parameter from medical diagnostic data
• CPC Class Codes: A61B 6/541 involving acquisition triggered by a physiological signal
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment

Abstract

A method for reconstructing an image of a beating heart in vivo is described. The method includes acquiring projection data for at least one z-location within a projection space, determining peaks in first order spatial moments for the projection space using the projection data, and reconstructing the image utilizing peaks in the first order spatial moments.

Claims

1. A method for reconstructing an image of a beating heart in vivo, said method comprising:

acquiring projection data for at least one z-location within a projection space;

determining peaks in spatial moments for the projection space using the projection data; and

reconstructing the image utilizing peaks in the spatial moments.

2. A method in accordance with claim 1 wherein acquiring a projection data comprises:

correlating a plurality of views with z-location information, wherein each view includes projection data acquired at the respective z-location; and

interpolating the projection data from each view to determine projection data at a desired z-location.

3. A method in accordance with claim 1 wherein determining peaks in the spatial moments comprises automatically extracting projection data for a region of interest (ROI) within each z-location.

4. A method in accordance with claim 3 wherein determining peaks in the spatial moments further comprises calculating spatial moments in the projection space using the ROI projection data.

5. A method in accordance with claim 4 wherein determining peaks in the spatial moments further comprises normalizing the spatial moments to determine the peaks.

6. A method in accordance with claim 1 wherein reconstructing the image comprises correlating a plurality of views with cardiac phase information based on the peaks in the spatial moments, wherein each view includes projection data at a z-location.

7. A method in accordance with claim 1 wherein reconstructing the image comprises utilizing a plurality of views correlated with z-location data and cardiac phase information to obtain a plurality of two-dimensional images at desired z-locations and cardiac phases, wherein each view includes projection data relevant to a respective z-location and cardiac phase.

8. A method in accordance with claim 7 wherein reconstructing the image further comprises combining the plurality of two-dimensional images to construct at least one three-dimensional image.

9. A system for reconstructing an image of a beating heart in vivo, said system comprising a computed tomography (CT) device including an x-ray source, an x-ray detector aligned with said x-ray source, a data acquisition system (DAS) for collecting data from said x-ray detector, and an image reconstructor for reconstructing an image from the collected data, said system configured to:

acquire projection data for at least one z-location within a projection space;

correlate a plurality of views with z-location information, wherein each view includes projection data acquired at the respective z-location;

extract projection data for a region of interest (ROI) within each z-location;

determine peaks in spatial moments for the projection space using the projection data; and

reconstruct an image utilizing peaks in said spatial moments.

10. A system in accordance with claim 9 wherein to acquire a plurality of projection data, said system configured to interpolate the projection data from each view to determine projection data at a desired z-location.

11. A system in accordance with claim 9 wherein to determine peaks in said spatial moments, said system configured to automatically extract projection data for the ROI within each z-location.

12. A system in accordance with claim 11 wherein to determine peaks in said spatial moments, said system further configured to:

determine spatial moments in the projection space using the ROI projection data; and

normalize said spatial moments to determine the peaks.

13. A system in accordance with claim 9 wherein to reconstruct the image, said system configured to:

determine cardiac phase information based on the peaks in said spatial moments; and

correlate each view with the cardiac phase information.

14. A system in accordance with claim 9 wherein to reconstruct the image, said system configured to utilize a plurality of views correlated with z-location data and cardiac phase information to obtain a plurality of two dimensional images at desired z-locations and cardiac phases.

15. A system in accordance with claim 14 wherein to reconstruct the image, said system further configured to construct a three-dimensional image by combining the plurality of two-dimensional images.

16. A computer readable medium encoded with a program executable by a computer for processing projection data for at least one z-location within a projection space to construct images of a beating heart in vivo, said program configured to instruct the computer to:

extract projection data for a region of interest (ROI) within each z-location; and

determine peaks in spatial moments for the projection space using the projection data.

17. A computer readable medium in accordance with claim 16 wherein to extract projection data, said program further configured to instruct the computer to automatically extract projection data for the ROI within each z-location.

18. A computer readable medium in accordance with claim 16 wherein to determine peaks in said spatial moments, said program further configured to instruct the computer to calculate spatial moments in the projection space using the ROI projection data.

19. A computer readable medium in accordance with claim 18 wherein to determine peaks in said spatial moments, said program further configured to instruct the computer to normalize said spatial moments to determine the peaks.

20. A computer readable medium in accordance with claim 16 wherein said program further configured to instruct the computer to:

determine cardiac phase information utilizing the determined peaks in said first order spatial moments; and

correlate a plurality of views with the cardiac phase information.

21. A method for reconstructing an image of a beating heart in vivo, said method comprising:

interpolating acquired projection data from a plurality of views to determine projection data at a plurality desired z-locations;

automatically extracting projection data for a region of interest (ROI) within each desired z-location;

determining peaks in first order spatial moments for a projection space using the extracted ROI projection data;

determining cardiac phase information based on the peaks in the first order spatial moments; and

reconstructing the image utilizing the cardiac phase information.

22. A method in accordance with claim 21 wherein determining peaks in first order spatial moments comprises:

calculating spatial moments in the projection data using the extracted ROI projection data; and

normalizing the spatial moments to determine the peaks.

23. A method in accordance with claim 21 wherein reconstructing comprises:

correlating the plurality of views with the cardiac phase information;

utilizing the plurality of views correlated with the cardiac phase information to obtain a plurality of two-dimensional images at a desired z-locations and cardiac phases; and

combining the plurality of two-dimensional images to construct at least one three-dimensional image.

24. A system for reconstructing an image of a beating heart in vivo, said system comprising a computed tomography (CT) device including:

a data acquisition system (DAS), configured to;

acquire projection data for at least one z-location within a projection space; and

interpolate the projection data to determine projection data for at least one view having at least one desired z-location;

a computer electrically coupled to the DAS configured to;

automatically extract projection data for a region of interest (ROI) within each desired z-location;

determine peaks in first order spatial moments for the projection space using the projection data; and

correlate each view with cardiac phase information; and

an image reconstructor configured to reconstruct an image utilizing peaks in the first order spatial moments.

25. A system in accordance with claim 24 wherein to determine peaks in first order spatial moments, said computer further configured to:

determine spatial moments in the projection space using the extracted ROI projection data; and

normalize said spatial moments to determine peaks.

26. A system in accordance with claim 24 wherein to correlate each view with cardiac phase information, said computer further configured to determine the cardiac phase information utilizing determined peaks in the first order spatial moments.

27. A system in accordance with claim 24 wherein to reconstruct a three-dimensional image, said reconstructor further configured to:

utilize a plurality of views correlated with cardiac phase information to obtain a plurality of two-dimensional images at desired z-locations and cardiac phases; and

combine the two-dimensional images to construct at least one three-dimensional image.

28. A computer readable medium encoded with a program executable by a computer for processing projection data for at least one z-location within a projection space to construct images of a beating heart in vivo, said program g configured to instruct the computer to:

automatically extract projection data for a region of interest (ROI) within each z-location;

determine peaks in first order spatial moments for the projection space using the projection data;

determine cardiac phase information utilizing the peaks in said first order spatial moments; and

correlate a plurality of views with the cardiac phase information.

29. A computer readable medium in accordance with claim 28 wherein to determine peaks in said first order spatial moments, said program further configured to instruct the computer to calculate spatial moments in the projection space using the ROI projection data.

30. A computer readable medium in accordance with claim 29 wherein to determine peaks in said first order spatial moments, said program further configured to instruct the computer to normalize said spatial moments to determine the peaks.