Automatic quality checks for radiotherapy contouring

Patent metadata

Field	Value
Publication number	US-11037298-B2
Application number	US-201916252854-A
Country	US
Kind code	B2
Filing date	Jan 21, 2019
Priority date	Sep 22, 2015
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

Systems, devices, methods, and computer processing products for automatically checking for errors in segmentation (contouring) using heuristic and/or statistical evaluation methods.

First claim

The invention claimed is:

1. A non-transitory computer readable medium containing program instructions for automatically evaluating a segment, wherein execution of the program instructions by a computer processing device causes the computer processing device to carry out the following steps:
generate a plurality of binary images for the segment;
combine the binary images of the segment using at least one of a plurality of Boolean operators to obtain a resulting binary image;
count the pixels/voxels in the resulting binary image;
determine whether the number of pixels/voxels is within a predetermined range; and
generate a signal to indicate that a segmentation error is present if the number of pixels/voxels is not within the predetermined range.

2. The non-transitory computer readable medium of claim 1 , further comprising evaluating the segment using a statistical evaluation method.

3. The non-transitory computer readable medium of claim 2 , wherein the evaluating comprises evaluating a shape of the segment and determining whether the shape of the segment is within a predetermined range of known shapes for the segment.

4. The non-transitory computer readable medium of claim 3 , further comprising generating a shape model based on a probabilistic distribution of shape variations found in the range of known shapes for the segment, and performing a statistical test to check if the shape of the segment is within the predetermined range.

5. The non-transitory computer readable medium of claim 4 , wherein the probabilistic distribution includes a multivariate normal distribution (μ, Σ).

6. The non-transitory computer readable medium of claim 5 , wherein the performing of the statistical check comprises evaluating how well the shape fits within the multivariate normal distribution using a probabilistic principal component analysis (PPCA).

7. The non-transitory computer readable medium of claim 4 , wherein if the shape of the segment does not fit within the multivariate normal distribution within a predetermined value, it is determined that a segmentation error is present.

8. The non-transitory computer readable medium of claim 1 , wherein the evaluating is automatic and in real-time.

Assignees

• Varian Medical Systems Int Ag

Inventors

• Albrecht Thomas
• Hess Peter
• Houhou Nawal

Classifications

• G06N7/01

  Probabilistic graphical models, e.g. probabilistic networks · CPC title

• G06T7/001 Primary

  using an image reference approach · CPC title

• G06V2201/03

  Recognition of patterns in medical or anatomical images · CPC title

• G06T7/50

  Depth or shape recovery · CPC title

• G06T2207/20076

  Probabilistic image processing · CPC title