System and method for simulataneous image artifact reduction and tomographic reconstruction of images depicting temporal contrast dynamics

Patent metadata

Field	Value
Publication number	US-10140734-B2
Application number	US-201615011101-A
Country	US
Kind code	B2
Filing date	Jan 29, 2016
Priority date	Jan 29, 2016
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

Described here is a system and method for image reconstruction that can automatically and iteratively produce multiple images from one set of acquired data, in which each of these multiple images corresponds to a subset of the acquired data that is self-consistent, but inconsistent with other subsets of the acquired data. The image reconstruction includes iteratively minimizing the rank of an image matrix whose columns each correspond to a different image, and in which one column corresponds to a user-provided prior image of the subject. The rank minimization is constrained subject to a consistency condition that enforces consistency between the forward projection of each column in the image matrix and a respective subset of the acquired data that contains data that is consistent with data in the subset, but inconsistent with data not in the subset.

First claim

The invention claimed is:

1. A method for reconstructing an image using a medical imaging system, the steps of the method comprising:
(a) acquiring data from a subject with the imaging system;
(b) initializing an image matrix having columns that each correspond to a different image of the subject that is consistent with at least a subset of the acquired data;
(c) generating an augmented image matrix by augmenting the image matrix with a prior image that depicts the subject by vectorizing the prior image and concatenating the vectorized prior image as a column in the image matrix;
(d) reconstructing at least one image of the subject from the data acquired in step (a) by:
(i) performing a rank minimization to minimize a matrix rank of the augmented image matrix; and
(ii) constraining the rank minimization of step (d)(i) subject to a consistency condition that promotes a forward projection of each column in the augmented image matrix to be consistent with a different subset of the acquired data, wherein each subset of the acquired data contains data that are consistent only with other data in that subset and are otherwise inconsistent with data in the other subsets of the acquired data;

wherein step (a) includes acquiring contrast-enhanced data from the subject using a cone beam computed tomography imaging system, and wherein the data are acquired over a short scan.

2. The method as recited in claim 1 , wherein step (d) includes reconstructing a plurality of images, and wherein each subset of the acquired data corresponds to a different temporal segment of the acquired data.

3. The method as recited in claim 1 , wherein step (d) includes reconstructing a plurality of images, and wherein each subset of the acquired data corresponds to a different angular segment of the acquired data.

4. The method as recited in claim 1 , wherein the prior image is reconstructed from the acquired data using at least one of a backprojection technique or an iterative reconstruction technique.

5. The method as recited in claim 2 , wherein step (a) includes acquiring data from a subject while a contrast agent is passing through vasculature in the subject.

6. The method as recited in claim 5 , wherein step (d) includes reconstructing a contrast-free image in which no contrast agent is depicted in the vasculature in the subject and at least one contrast image in which contrast agent is depicted in the vasculature in the subject, and wherein the contrast-free image and at least one contrast image are consistent with different subsets of the acquired data.

7. The method as recited in claim 6 , further comprising producing a difference image that depicts the vasculature in the subject by computing a difference between the contrast-free image and the at least one contrast image.

8. The method as recited in claim 5 , wherein step (d) includes reconstructing a plurality of contrast images in which contrast agent is depicted in the vasculature in the subject, and wherein each contrast image is consistent with different subsets of the acquired data.

9. The method as recited in claim 8 , further comprising producing a difference image that depicts the vasculature in the subject by computing a difference between at least two of the plurality of contrast images.

10. The method as recited in claim 5 , wherein the prior image is reconstructed from the acquired data using at least one of a backprojection technique or an iterative reconstruction technique.

11. A method for reconstructing an image using a medical imaging system, the steps of the method comprising:
(a) acquiring data from a subject with the imaging system;
(b) initializing an image matrix having columns that each correspond to a different image of the subject that is consistent with at least a subset of the acquired data;
(c) generating an augmented image matrix by augmenting the image matrix with a prior image that depicts the subject by vectorizing the prior image and concatenating the vectorized prior image as a column in the image matrix;
(d) reconstructing at least one image of the subject from the data acquired in step (a) by:
(i) performing a rank minimization to minimize a matrix rank of the augmented image matrix; and
(ii) constraining the rank minimization of step (d)(i) subject to a consistency condition that promotes a forward projection of each column in the augmented image matrix to be consistent with a different subset of the acquired data, wherein each subset of the acquired data contains data that are consistent only with other data in that subset and are otherwise inconsistent with data in the other subsets of the acquired data;

wherein the data acquired in step (a) is representative of a time series of images and step (d) includes reconstructing the time series of images, wherein each column in the augmented image matrix other than the column corresponding to the prior image corresponds to one of the images in the time series.

12. The method as recited in claim 11 , wherein the prior image is reconstructed from the acquired data using at least one of a backprojection technique or an iterative reconstruction technique.

13. A method for reconstructing an image using a medical imaging system, the steps of the method comprising:
(a) acquiring data from a subject with the imaging system;
(b) initializing an image matrix having columns that each correspond to a different image of the subject that is consistent with at least a subset of the acquired data;
(c) generating an augmented image matrix by augmenting the image matrix with a prior image that depicts the subject by vectorizing the prior image and concatenating the vectorized prior image as a column in the image matrix;
(d) reconstructing at least one image of the subject from the data acquired in step (a) by:
(i) performing a rank minimization to minimize a matrix rank of the augmented image matrix; and
(ii) constraining the rank minimization of step (d)(i) subject to a consistency condition that promotes a forward projection of each column in the augmented image matrix to be consistent with a different subset of the acquired data, wherein each subset of the acquired data contains data that are consistent only with other data in that subset and are otherwise inconsistent with data in the other subsets of the acquired data;

wherein the data acquired in step (a) is representative of a time series of images and step (d) includes reconstructing the time series of images, wherein each column in the augmented image matrix other than the column corresponding to the prior image corresponds to one of the images in the time series; and
wherein the prior image is processed using a segmenting and compensation technique to segment regions in the prior image that are prone to motion and replace the segmented regions with a positive mean image intensity value from tissues adjacent the regions in the prior image that are prone to motion.

14. The method as recited in claim 11 , wherein the time series of images depict different cardiac phases of a subject's heart and each subset of the acquired data corresponds to data acquired during a given cardiac phase.

15. The method as recited in claim 1 , wherein step (a) includes acquiring contrast-enhanced data from a subject's breast using a cone beam computed tomography imaging system.

Assignees

• Wisconsin Alumni Res Found

Inventors

• Chen Guang-Hong

Classifications

• G06T12/20 Primary

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

• G06T12/30 Primary

  Image post-processing, e.g. metal artefact correction · CPC title

• G06T11/006

  Physics · mapped topic

• G06T2211/436

  Limited angle · CPC title

• G06T2211/421

  Filtered back projection [FBP] · CPC title