System and method for regularized reconstruction of phase contrast computerized tomography

Patent metadata

Field	Value
Publication number	US-9805481-B2
Application number	US-201615004293-A
Country	US
Kind code	B2
Filing date	Jan 22, 2016
Priority date	Jan 22, 2016
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

Reconstructing under-sampled PCT data includes obtaining under-sampled scan data of a subject-under-test, the object scan performed on a phase contrast computed tomography (PCT) system, performing a regularized Fourier analysis on the under-sampled scan data, correcting for one or more PCT system contributions to the under-sampled scan data by dividing the computed Fourier coefficients by Fourier coefficients representative of the one or more PCT system contributions, obtaining at least one of an absorption sinogram, a differential phase sinogram, and a dark field sinogram from the corrected Fourier coefficients, and performing tomographic reconstruction on the obtained absorption sinogram, the obtained differential phase sinogram, and the obtained dark field sinogram. A system and non-transitory computer readable medium are also disclosed.

First claim

The invention claimed is:

1. A method for reconstructing under-sampled phase contrast computed tomography data, the method comprising:
obtaining under-sampled scan data of a subject-under-test, the object scan performed on a phase contrast computed tomography (PCT) system;
performing a regularized Fourier analysis on the under-sampled scan data;
correcting for one or more PCT system contributions to the under-sampled scan data by dividing the computed Fourier coefficients by Fourier coefficients representative of the one or more PCT system contributions;
obtaining at least one of an absorption sinogram, a differential phase sinogram, and a dark field sinogram from the corrected Fourier coefficients; and
performing tomographic reconstruction on the obtained absorption sinogram, the obtained differential phase sinogram, and the obtained dark field sinogram.

2. The method of claim 1 , including collecting the under-sampled object scan data in a randomized manner.

3. The method of claim 1 , including obtaining the Fourier coefficients representative of the one or more PCT system contributions by performing an air scan.

4. The method of claim 1 , wherein the dividing step corrects the computed Fourier coefficients for PCT system non-homogeneities.

5. The method of claim 1 , the regularized Fourier analysis step including solving a minimization equation expressed as

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6. The method of claim 1 , wherein the regularized Fourier analysis step includes the correcting step.

7. The method of claim 6 , including the regularized Fourier analysis step including solving a minimization equation expressed as

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8. A non-transitory computer-readable medium having stored thereon instructions which when executed by a processor cause the processor to perform a method for reconstructing under-sampled phase contrast computed tomography data, the method comprising:
obtaining under-sampled scan data of a subject-under-test, the object scan performed on a phase contrast computed tomography (PCT) system;
performing a regularized Fourier analysis on the under-sampled scan data;
computing Fourier coefficients for the under-sampled scan data;
correcting for one or more PCT system contributions to the under-sampled scan data by dividing the computed Fourier coefficients by Fourier coefficients representative of the one or more PCT system contributions;
obtaining at least one of an absorption sinogram, a differential phase sinogram, and a dark field sinogram from the corrected Fourier coefficients; and
performing tomographic reconstruction on the obtained absorption sinogram, the obtained differential phase sinogram, and the obtained dark field sinogram.

9. The non-transitory computer-readable medium of claim 8 , including instructions to cause the processor to collect the under-sampled object scan data in a randomized manner.

10. The non-transitory computer-readable medium of claim 8 , including instructions to cause the processor to obtain the Fourier coefficients representative of the one or more PCT system contributions by performing an air scan.

11. The non-transitory computer-readable medium of claim 8 , including instructions to cause the processor to correct the computed Fourier coefficients for PCT system non-homogeneities during the dividing step.

12. The non-transitory computer-readable medium of claim 8 , including instructions to cause the processor to perform the regularized Fourier analysis step by solving a minimization equation expressed as

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13. The non-transitory computer-readable medium of claim 8 , including instructions to cause the processor to combine the regularized Fourier analysis step and the correcting step.

14. The non-transitory computer-readable medium of claim 13 , including instructions to cause the processor to perform the regularized Fourier analysis step by solving a minimization equation expressed as

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Assignees

• Gen Electric

Inventors

• Sperl Jonathan Immanuel
• Beque Dirk

Classifications

• G06T12/20

  Inverse problem, i.e. transformations from projection space into object space · CPC title

• G06T12/10

  Image preprocessing, e.g. calibration, positioning of sources or scatter correction · CPC title

• G01N2223/401

  image processing · CPC title

• G06T2211/40

  Computed tomography · CPC title

• G01N23/046 Primary

  using tomography, e.g. computed tomography [CT] · CPC title