Methods and apparatus for facilitating a reduction in artifacts

• US 7,272,429 B2
• Filed: 11/27/2002
• Issued: 09/18/2007
• Est. Priority Date: 11/27/2002
• Status: Expired due to Fees

• Current Assignee: GE Medical Systems Global Technology Company LLC (GE Healthcare Technologies, Inc.)
• Original Assignee: GE Medical Systems Global Technology Company LLC (GE Healthcare Technologies, Inc.)
• Inventors: Sabol, John Michael, Avinash, Gopal B., Walker, Matthew Joseph
• Primary Examiner(s): Mantis Mercader; Eleni
• Assistant Examiner(s): Cheng; Jacqueline
• Application Number:
  US10/306,197
• Publication Number:
  US 20040102688A1
• Time in Patent Office: 1,756 Days
• Field of Search: 600/425, 600/407, 378/4, 378/5, 382/131
• US Class Current: 600/407
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/4035 the source being combined with a filter or grating
• CPC Class Codes: A61B 6/405 Source units specially adapted to modify characteristics of the beam during the data acquisition process A61B6/4021, A61B6/4035 take precedence
• CPC Class Codes: A61B 6/4085 Cone-beams
• CPC Class Codes: A61B 6/4241 using energy resolving detectors, e.g. photon counting
• CPC Class Codes: A61B 6/482 involving multiple energy imaging

Abstract

A method for facilitating a reduction in artifacts includes receiving data regarding a first energy spectrum of a scan of an object, and receiving data regarding a second energy spectrum of a scan of the object, wherein the second energy spectrum is different than the first energy spectrum. The method further includes reconstructing at least one original first energy image using the first energy spectrum data, reconstructing at least one original second energy image using the second energy spectrum data, transforming at least one original second energy image into at least one transformed first energy image, and combining at least one original first energy image with at least one transformed first energy image to generate a combined first energy image.

Claims

1. A method for facilitating a reduction in artifacts, said method comprising:

receiving data regarding a scan of an object, the data corresponding to a plurality of sequential projections comprising a first set of projections corresponding to a first energy spectrum and a second set of projections corresponding to a second energy spectrum, the first set of projections interleaved with the second set of projections;

reconstructing at least one original first energy image using the data corresponding to the first set of projections;

reconstructing at least one original second energy image using the data corresponding to the second set of projections;

transforming at least one original first energy image into at least one transformed second energy image;

transforming at least one original second energy image into at least one transformed first energy image;

combining at least one original first energy image with at least one transformed first energy image to generate at least one combined first energy image; and

combining at least one original second energy image with at least one transformed second energy image to generate at least one combined second energy image.

2. A method in accordance with claim 1 further comprising decomposing the combined first and second energy images to generate at least one quantitative material characterization image.

3. A method in accordance with claim 2 wherein said decomposing comprises at least one of decomposing by a Compton and photoelectric decomposition, decomposing by a basis material decomposition (BMD), and decomposing by a logarithm subtraction decomposition (LSD).

4. A method in accordance with claim 1 wherein said receiving data comprises receiving data comprising fan-beam projection data, said method further comprising rebinning the fan-beam projection data into equivalent parallel-beam projection data.

5. A method for facilitating a reduction in artifacts, said method comprising:

receiving data from a scan of an object, the data corresponding to a plurality of sequential projections comprising a first set of projections corresponding to a first energy spectrum and a second set of projections corresponding to a second energy spectrum, the first set of projections interleaved with the second set of projections;

reconstructing at least one original first energy image using the data corresponding to the first set of projections;

reconstructing at least one original second energy image using the data corresponding to the second set of projections;

transforming at least one original first energy image into at least one transformed second energy image;

transforming at least one original second energy image into at least one transformed first energy image;

reprojecting at least one transformed first energy image to generate reprojected first energy spectrum data;

reprojecting at least one transformed second energy image to generate reprojected second energy spectrum data;

combining the first energy spectrum data with the reprojected first energy spectrum data to generate combined first energy spectrum data; and

combining the second energy spectrum data with the reprojected second energy spectrum data to generate combined second energy spectrum data.

6. A method in accordance with claim 5 further comprising decomposing the combined first energy spectrum data and the combined second energy spectrum data to generate at least one quantitative material characterization image.

7. A method in accordance with claim 6 wherein said decomposing comprises at least one of decomposing by a Compton and photoelectric decomposition, decomposing by a basis material decomposition (BMD), and decomposing by a logarithm subtraction decomposition (LSD).

8. A method in accordance with claim 5 further comprising reconstructing at least one combined first energy image using the combined first energy spectrum data.

9. A method in accordance with claim 8 further comprising reconstructing at least one combined second energy image using the combined second energy spectrum data.

10. A method in accordance with claim 9 further comprising decomposing the combined first and second energy images to generate at least one quantitative material characterization image.

11. A method in accordance with claim 10 wherein said decomposing comprises at least one of decomposing by a Compton and photoelectric decomposition, decomposing by a basis material decomposition (BMD), and decomposing by a logarithm subtraction decomposition (LSD).

12. A multi-energy computed tomography (MECT) system comprising:

at least one radiation source configured to sequentially change the energy spectrum of the radiation between a higher energy and a lower energy during a single scan by sequentially alternating the source energy;

at least one radiation detector; and

a computer operationally coupled to said at least one radiation source and said at least one radiation detector, said computer configured to;

receive data from a scan of an object, said data corresponding to a plurality of sequential projections comprising a first set of projections corresponding to a first energy spectrum and a second set of projections corresponding to a second energy spectrum, said first set of projections interleaved with said second set of projections;

transform said data corresponding to said first set of projections into transformed second energy spectrum data;

transform said data corresponding to said second set of projections into transformed first energy spectrum data;

reconstruct at least one first energy image using said data corresponding to said first set of projections;

reconstruct at least one second energy image using said data corresponding to said second set of projections;

reconstruct at least one transformed first energy image using said transformed first energy spectrum data;

reconstruct at least one transformed second energy image using said transformed second energy spectrum data;

combine at least one first energy image with at least one transformed first energy image to generate at least one combined first energy image; and

combine at least one second energy image with at least one transformed second energy image to generate at least one combined second energy image.

13. An MECT system in accordance with claim 12, wherein said computer further configured to decompose said combined second energy image and said combined first energy image to generate at least one quantitative material characterization image.

14. An MECT system in accordance with claim 13, wherein said computer configured to decompose at least one combined second energy image using at least one of a Compton and photoelectric decomposition, a basis material decomposition (BMD), and a logarithm subtraction decomposition (LSD).

15. A multi-energy computed tomography (MECT) system comprising:

at least one radiation source;

at least one radiation detector; and

a computer operationally coupled to said at least one radiation source and said at least one radiation detector, said computer configured to;

receive data from a scan of an object, said data corresponding to a plurality of sequential projections comprising a first set of projections corresponding to a first energy spectrum and a second set of projections corresponding to a second energy spectrum, said first set of projections interleaved with said second set of projections;

transform said data corresponding to said first set of projections into transformed second energy spectrum data;

transform said data corresponding to said second set of projections into transformed first energy spectrum data;

combine said first energy spectrum data with said transformed first energy spectrum data to generate combined first energy spectrum data; and

combine said second energy spectrum data with said transformed second energy spectrum data to generate combined second energy spectrum data.

16. An MECT system in accordance with claim 15, wherein said computer further configured to decompose said combined first energy spectrum data and said combined second energy spectrum data to generate at least one quantitative material characterization image.

17. An MECT system in accordance with claim 16, said computer configured to decompose said combined first and second energy spectrum data using at least one of a Compton and photoelectric decomposition, a basis material decomposition (BMD), and a logarithm subtraction decomposition (LSD).

18. An MECT system in accordance with claim 15, wherein said computer further configured to reconstruct at least one combined first energy image using said combined first energy spectrum data.

19. An MECT system in accordance with claim 18, wherein said computer further configured to reconstruct at least one combined second energy image using said combined second energy spectrum data.

20. An MECT system in accordance with claim 19, wherein said computer further configured to decompose said combined first energy image and said combined second energy image to generate at least one quantitative material characterization image.

21. An MECT system in accordance with claim 20, wherein said computer configured to decompose said combined first and second energy images using at least one of a Compton and photoelectric decomposition, a basis material decomposition (BMD), and a logarithm subtraction decomposition (LSD).