Image processing apparatus, image processing method, and storage medium

Patent metadata

Field	Value
Publication number	US-10206587-B2
Application number	US-201615344159-A
Country	US
Kind code	B2
Filing date	Nov 4, 2016
Priority date	May 16, 2014
Publication date	Feb 19, 2019
Grant date	Feb 19, 2019

Abstract

An image processing apparatus according to an embodiment includes a processing circuitry. The processing circuitry is configured to obtain images in a time series including images of a blood vessel of a subject and correlation information indicating a correlational relationship between physical indices of the blood vessel and function indices of the blood vessel related to vascular hemodynamics, calculate blood vessel morphology indices in a time series indicating morphology of the blood vessel of the subject, on a basis of the images in the time series, and identify a function index of the blood vessel of the subject, by using a physical index of the blood vessel of the subject obtained from the blood vessel morphology indices, on a basis of the correlation information.

First claim

What is claimed is:

1. An image processing apparatus, comprising:
processing circuitry configured to
obtain images in a time series including images of a blood vessel of a subject and correlation information indicating a correlational relationship between physical indices of the blood vessel and parameters for a fluid analysis of the blood vessel,
calculate blood vessel morphology indices in a time series indicating morphology of the blood vessel of the subject, based on the images in the time series,
calculate a physical index of the blood vessel of the subject, based on the blood vessel morphology indices in the time series, the physical index indicating a temporal change ratio of the blood vessel morphology indices,
identify a parameter for the fluid analysis of the blood vessel by using the calculated physical index of the blood vessel of the subject, based on the correlation information, and
identify a pressure ratio in the blood vessel by performing the fluid analysis using the identified parameter and at least one of the calculated blood vessel morphology indices; and

a display that displays the identified pressure ratio in the blood vessel.

2. The image processing apparatus according to claim 1 , wherein
the processing circuitry is further configured to set an identification target region for the pressure ratio in the blood vessel, in a blood vessel region included in the images, and
the processing circuitry is further configured to
calculate the physical index of the identification target region from the blood vessel morphology indices, and
identify the parameter for the fluid analysis, based on the correlation information and the calculated physical index.

3. The image processing apparatus according to claim 2 , wherein
the processing circuitry is further configured to identify a parameter from the correlation information that corresponds to the physical index equal to the calculated physical index, as the parameter for the fluid analysis.

4. The image processing apparatus according to claim 2 , wherein the processing circuitry is further configured to
set an ex-ante distribution of the parameter for the fluid analysis, which is related to at least one of a shape in a stress-free state and a physical property value of the identification target region,
calculate a prediction value of at least one of a blood flow amount index and a blood vessel morphology index of the identification target region, based on the ex-ante distribution,
calculate, based on the images, an observed value of at least one of the blood flow amount index and the blood vessel morphology index,
identify an ex-post distribution of the parameter for the fluid analysis, based on the prediction value, the observed value, and a parameter from the correlation information that corresponds to the physical index equal to the calculated physical index, so that the prediction value matches the observed value, and
identify the pressure ratio in the blood vessel, based on an identified value in the ex-post distribution.

5. The image processing apparatus according to claim 4 , wherein the processing circuitry is further configured to
identify the ex-post distribution by setting a data distribution related to an error between the prediction value and the observed value, and further performing a statistical identifying process on a probability distribution indicated by the pressure ratio of the blood vessel and on the data distribution, with respect to the ex-ante distribution, and
keep resetting the ex-ante distribution and performing the statistical identifying process, until the ex-post distribution satisfies an identification ending condition.

6. The image processing apparatus according to claim 4 , wherein the processing circuitry is further configured to
obtain first information in which the parameter for the fluid analysis is kept in correspondence with at least one of the blood flow amount index and the blood vessel morphology index, and
calculate, as the prediction value, at least one of the blood flow amount index and the blood vessel morphology index that is from the first information, and that corresponds to the parameter for the fluid analysis indicated by the ex-ante distribution.

7. The image processing apparatus according to claim 4 , wherein the processing circuitry is further configured to
calculate blood vessel morphology indices in a time series and blood vessel cross-sectional shape change indices in a time series with respect to an analysis target region in the blood vessel region, based on the images,
construct a dynamic model related to the analysis target region, based on the images, the blood vessel morphology indices in the time series, and the blood vessel cross-sectional shape change indices in the time series, and
calculate the prediction value by analyzing the dynamic model.

8. The image processing apparatus according to claim 4 , wherein the processing circuitry is further configured to identify the pressure ratio of the blood vessel by constructing a dynamic model to which the identified value in the ex-post distribution is assigned, and performing either a blood vessel stress analysis or a blood fluid analysis on the dynamic model.

9. The image processing apparatus according to claim 1 , wherein the physical indices are at least one of a blood vessel cross-sectional shape change index indicating a change index of a cross-sectional shape of the blood vessel and a blood flow resistance index indicating an index of a blood flow resistance.

10. The image processing apparatus according to claim 1 , wherein the processing circuitry is further configured to cause the display to display a combined image obtained by combining a first image indicating the correlation information with a second image indicating the identified pressure ratio.

11. The image processing apparatus according to claim 1 , wherein the processing circuitry is further configured to identify the pressure ratio in the blood vessel by further using a concentration change amount of the images.

12. The image processing apparatus according to claim 1 , wherein the processing circuitry is further configured to
set, in a blood vessel region included in the images, a first cross-sectional plane of a blood vessel having a stenosis on a downstream side of the stenosis and a second cross-sectional plane of a blood vessel having no stenosis,
calculate the blood vessel morphology indices in the time series with respect to each of the first cross-sectional plane and the second cross-sectional plane, and further calculate a blood vessel cross-sectional shape change index for each of the first cross-sectional plane and the second cross-sectional plane based on the blood vessel morphology indices, and
identify the pressure ratio in the blood vessel, by using the blood vessel cross-sectional shape change index for each of the first cross-sectional plane and the second cross-sectional plane, as the physical index.

13. The image processing apparatus according to claim 12 , wherein the correlation information is a one-dimensional mathematical model related to dynamics.

14. The image processing apparatus according to claim 12 , wherein the processing circuitry is further configured to set the first cross-sectional plane in a vicinity of a distal part of a coronary artery having the stenosis, and set the second cross-sectional plane in a vicinity of a starting part of a coronary artery having no stenosis.

15. The image processing apparatus according to claim 12 , wherein the blood vessel morphology index is a radius and a wall thickness of each of th

Assignees

• Toshiba Medical Sys Corp

Inventors

• Kano Akira
• Hirohata Kenji
• Ooga Junichiro
• Kato Mitsuaki
• Hongo Takuya
• Goryu Akihiro
• Kaminaga Shigeo
• Fujisawa Yasuko
• Wakai Satoshi
• Ikeda Yoshihiro
• Arakita Kazumasa

Classifications

• A61B34/00

  Computer-aided surgery; Manipulators or robots specially adapted for use in surgery · CPC title

• A61B5/748

  Selection of a region of interest, e.g. using a graphics tablet · CPC title

• A61B5/7278

  Artificial waveform generation or derivation, e.g. synthesizing signals from measured signals · CPC title

• A61B5/7246

  using correlation, e.g. template matching or determination of similarity · CPC title

• A61B5/1079

  using optical or photographic means · CPC title