Method and system for tomosynthesis projection images enhancement

Patent metadata

Field	Value
Publication number	US-2016183901-A1
Application number	US-201514984846-A
Country	US
Kind code	A1
Filing date	Dec 30, 2015
Priority date	Dec 31, 2014
Publication date	Jun 30, 2016
Grant date	—

Abstract

Method and system for obtaining images of an object of interest using a system comprising an x-ray source facing a detector. The method and system enable the acquiring of a plurality of 2D projection images of the object of interest in a plurality of orientations. A selected 2D projection image such as the zero projection of the plurality of projections can be enhanced by using at least a subset of the plurality of tomosynthesis projection images. The obtained enhanced 2D projection image is displayed for review.

First claim

What is claimed is:

1 . Method for obtaining at least one enhanced image of an object of interest using a system comprising an x-ray source facing a detector, the method comprising:
acquiring a plurality of 2D tomosynthesis projection images of the object of interest in a plurality of orientations; enhancing a selected projection image of the plurality of projections using at least a subset of the plurality of tomosynthesis projection images; and displaying the enhanced 2D projection image.

2 . The method according to claim 1 , wherein the enhancing step further comprises:
for each pixel (i,j) of the selected projection image and for a given height, accumulating the values of the corresponding pixel position in at least one of the tomosynthesis projections; ranking the accumulated values for each pixel over all possible heights; determining the most likely height for each pixel (i,j) by selecting the maximum accumulated value; and combining (i,j)'s level with the determined maximum values for each pixel (i,j).

3 . The method according to claim 2 , wherein the accumulating step is performed for different frequency bands obtained by filtering the projection images.

4 . The method according to claim 2 , wherein the most likely height of each pixel (i,j) is obtained as a combination of maximum accumulated value and 3D marks provided by a CAD system or indicated by a user through a 3D review system.

5 . The method according to claim 2 , wherein the most likely height of each pixel (i,j) is stored as a height map associated to the enhanced 2D projection image.

6 . The method according to claim 1 , wherein the selected projection image is the central projection (0°), which is the projection perpendicular to or closest to the perpendicular of the detector.

7 . The method according to claim 1 , wherein at least one tomosynthesis projection image is denoised prior to improving the image quality of at least one of said at least one tomosynthesis projection image.

8 . The method according to claim 1 , further comprising:
enhancing the tomosynthesis projection images for each of the plurality of orientations; projecting each enhanced image on an isocentric virtual detector, wherein the normal to the virtual detector points towards the source position; and displaying successively the virtual projections.

9 . The method according claim 8 , wherein the displaying step is performed at an adjustable speed.

10 . A computer program product, which computer program product comprises program instructions for carrying out the steps of the method according to claim 1 , when said product is executed on a computer.

11 . A computer readable medium storing program instructions, which, when executed by a computer, cause the computer to perform the method according to claim 1 .

12 . A system for obtaining enhanced images of an object of interest comprising:
an imaging system comprising an x-ray source and a detector configured to acquire a plurality of 2D tomosynthesis projection images of the object of interest; a processing unit configured to compute for a selected projection image of the plurality of projection images an enhancement using at least a subset of the plurality of projections; and a display unit configured to display the enhanced projection image.

13 . The system according to claim 12 , wherein the object of interest is a patient's breast.

14 . The system according to claim 12 , wherein in computing the enhancement, the processing unit is further configured to:
for each pixel (i,j) of the selected projection image and for a given height, accumulate the values of the corresponding pixel position in at least one of the tomosynthesis projections; rank the accumulated values for each pixel over all possible heights; determine the most likely height for each pixel (i,j) by selecting the maximum accumulated value; and combine (i,j)'s level with the determined maximum values for each pixel (i,j).

15 . The system according to claim 14 , wherein the most likely height of each pixel (i,j) is obtained as a combination of maximum accumulated value and 3D marks provided by a CAD system or indicated by a user through a 3D review system.

16 . The system according to claim 15 , wherein the most likely height of each pixel (i,j) is stored as a height map associated to the enhanced 2D projection image.

17 . The system according to claim 12 , wherein the selected projection image is the central projection (0°), which is the projection perpendicular to or closest to the perpendicular of the detector.

18 . The system according to claim 12 , wherein at least one tomosynthesis projection image is denoised prior to improving the image quality of at least one of said at least one tomosynthesis projection image.

19 . The system according to claim 12 , wherein the system is further configured to:
enhance, via the processing unit, the tomosynthesis projection images for each of the plurality of orientations; enable a projection of each enhanced image on an isocentric virtual detector, wherein the normal to the virtual detector points towards the source position; and display, via the display unit, successively the virtual projections.

Assignees

• Gen Electric

Inventors

• Bernard Sylvain

Classifications

• G06T12/10

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

• G06T2211/436

  Limited angle · CPC title

• A61B6/542

  involving control of exposure · CPC title

• A61B6/5258

  involving detection or reduction of artifacts or noise · CPC title

• A61B6/502

  for diagnosis of breast, i.e. mammography · CPC title