EP-4736739-A1 - ANALYSIS PROCESSING DEVICE, OPTICAL COHERENCE TOMOGRAPHY DEVICE, ANALYSIS PROCESSING METHOD, AND PROGRAM

EP4736739A1EP 4736739 A1EP4736739 A1EP 4736739A1EP-4736739-A1

Abstract

This analysis processing device includes an acquisition unit, an analysis unit, and a display control unit. The acquisition unit acquires two or more items of motion contrast data for the same cross-section of an object under measurement at mutually different inter-scan time intervals, the motion contrast data being obtained by repeating a B-scan three or more times on the cross-section. The analysis unit executes an analysis process for deriving the temporal variation of motion contrast intensity in the cross-section on the basis of the two or more items of motion contrast data. The display control unit causes a display means to display an image representing the temporal variation obtained using the analysis process.

Inventors

MINO TOSHIHIRO
MORIGUCHI YOSHIKIYO
ISHIKAWA AKIKO

Assignees

Topcon Corporation

Dates

Publication Date: 20260506
Application Date: 20240613

Claims (18)

An analysis processing apparatus, comprising: an acquisition unit configured to acquire two or more pieces of motion contrast data of a cross-section at interscan time intervals different from each other, the two or more pieces of motion contrast data being acquired by repeatedly performing B-scans three or more times on the same cross-section in an object to be measured; an analyzer configured to perform analysis processing for obtaining a time variation of a motion contrast intensity in the cross-section based on the two or more pieces of motion contrast data; and a display controller configured to cause an image representing the time variation obtained by performing the analysis processing to be displayed on a display means.
The analysis processing apparatus of claim 1, wherein the acquisition unit is configured to acquire two or more contrast data groups acquired at timings different from each other, each of the two or more contrast data groups including the two or more pieces of motion contrast data, the analyzer is configured to sequentially perform the analysis processing on the each of the two or more contrast data groups, and the display controller is configured to cause two or more images, each of the two or more images representing the time variation obtained by performing the analysis processing, to be simultaneously displayed on a screen of the display means, or to cause the two or more images, each of the two or more images representing the time variation, at a same position to be sequentially displayed on the display means.
The analysis processing apparatus of claim 1 or 2, wherein the analyzer is configured to generate the image representing the time variation in real time.
The analysis processing apparatus of claim 1 or 2, wherein the analyzer is configured to generate the image representing the time variation based on a saturation time of the motion contrast intensity at each of positions in the cross-section.
The analysis processing apparatus of claim 1 or 2, wherein the analyzer is configured to generate the image representing a time change in the time variation at a designated position in the cross-section.
The analysis processing apparatus of claim 5, wherein the display controller is configured to cause information representing the time change in the time variation to be displayed on the display means.
The analysis processing apparatus of claim 1 or 2, further comprising an adjuster configured to adjust one or more parameters of the B-scan based on the time variation of the motion contrast intensity at each of one or more positions in the cross-section.
The analysis processing apparatus of claim 7, wherein the one or more scan parameters include an interscan time, and number of repetitions of the B-scan for a same cross-section.
An optical coherence tomography apparatus, comprising: an optical system configured to perform optical coherence tomography on the object to be measured; and the analysis processing apparatus of claim 1 or 2, the analysis processing apparatus being configured to cause an image representing the time variation to be displayed on the display means based on the two or more pieces of motion contrast data acquired by repeatedly performing three or more B-scans on the same cross-section in the object to be measured using the optical system.
An analysis processing method, comprising: an acquisition step of acquiring two or more pieces of motion contrast data of a cross-section at interscan time intervals different from each other, the two or more pieces of motion contrast data being acquired by repeatedly performing B-scans three or more times on the same cross-section in an object to be measured; an analyzing step of performing analysis processing for obtaining a time variation of a motion contrast intensity in the cross-section based on the two or more pieces of motion contrast data; and a display control step of causing an image representing the time variation obtained by performing the analysis processing to be displayed on a display means.
The analysis processing method of claim 10, wherein the acquisition step is performed to acquire two or more contrast data groups acquired at timings different from each other, each of the two or more contrast data group including the two or more pieces of motion contrast data, the analyzing step is performed to sequentially perform the analysis processing on the each of the two or more contrast data groups, and the display control step is performed to cause two or more images, each of the two or more images representing the time variation obtained by performing the analysis processing, to be simultaneously displayed on a screen of the display means, or to cause the two or more images, each of the two or more images representing the time variation, at a same position to be sequentially displayed on the display means.
The analysis processing method of claim 10 or 11, wherein the analyzing step is performed to generate the image representing the time variation in real time.
The analysis processing method of claim 10 or 11, wherein the analyzing step is performed to generate the image representing the time variation based on a saturation time of the motion contrast intensity at each of positions in the cross-section.
The analysis processing method of claim 10 or 11, wherein the analyzing step is performed to generate information representing a time change in the time variation at a designated position in the cross-section.
The analysis processing method of claim 14, wherein the display control step is performed to cause information representing the time change in the time variation to be displayed on the display means.
The analysis processing method of claim 10 or 11, further comprising an adjusting step of adjusting one or more scan parameters of the B-scan based on the time variation of the motion contrast intensity at each of one or more positions in the cross-section.
The analysis processing method of claim 16, wherein the one or more scan parameters include an interscan time, and number of repetitions of the B-scan for a same cross-section.
A program of causing a computer to execute each step of the analysis processing method of claim 10 or 11.

Description

[TECHNICAL FIELD] The present invention relates to an analysis processing apparatus, an optical coherence tomography apparatus, an analysis processing method, and a program. [BACKGROUND ART] Optical coherence tomography (OCT) that is used for forming images representing the surface morphology or the internal morphology of an object to be measured using light beam emitted from a laser light source or the like have been known. OCT is not invasive on the human body, and therefore is expected to be applied to the medical field or the biological field, in particular. For example, in the ophthalmic field, apparatuses for forming images of the fundus, the cornea, or the like have been in practical use. Such apparatuses using a method of OCT (OCT apparatuses) can be applied to observe various sites of an eye to be examined. In addition, because of the ability to acquire high-definition images, the OCT apparatuses are applied to the diagnosis of various eye diseases. In particular, OCT angiography (OCTA) has recently attracted attention as a method for imaging components that change within the minute time between OCT scans by repeatedly performing OCT scans on the same location of the object to be measured. Such OCTA is used as a method for visualizing information on a structure of a vasculature in a retina and/or a choroid within a living body. For example, Patent Document 1, Patent Document 2, and Non-Patent Document 1 disclose Variable Interscan Time Analysis (VISTA) for analyzing a relative blood flow velocity by utilizing a dependency of OCT signals (OCTA images) in the interscan time (time between scans). For example, as described in Non-Patent Document 1, a relative blood flow distribution in the retinal/choroidal vessel layer such as a superficial layer of the retina, a deep layer of the retina, and a choriocapillaris can be provided by using VISTA. VISTA is expected to be used to evaluate the activity of blood vessels, especially capillary or neovascular. [PRIOR ART DOCUMENTS] [PATENT DOCUMENTS] [PATENT DOCUMENT 1] U.S. Unexamined Patent Application Publication No. 2018/0315194[PATENT DOCUMENT 2] U.S. Unexamined Patent Application Publication No. 2020/0064118 [NON-PATENT DOCUMENTS] [NON-PATENT DOCUMENT 1] Stefan B. Ploner et al., "Toward quantitative OCT angiography: visualizing blood flow speeds in ocular pathology using variable interscan time analysis (VISTA)", Retina. Auther manuscript; available in PMC 2017 December 01 [SUMMARY OF THE INVENTION] [PROBLEMS TO BE SOLVED BY THE INVENTION] Generally, three-dimensional volume data of the object to be measured is acquired by performing OCT scan, the region of interest is identified in a projection image generated from the acquired volume data, and VISTA is performed to observe the identified region of interest in detail. In such conventional VISTA, it is practically impossible to acquire results of time analysis, such as time variation of relative blood flow velocity, in real time. Further, VISTA requires repeatedly performing OCT scans on the same location of the object to be measured. Thus, compared to OCTA, VISTA significantly increases both measurement time and analysis time, while also requiring a significantly larger amount of data for analysis. As a result, conventional VISTA cannot acquire analysis results in real time, and while VISTA can provide spatial distribution of relative blood flow velocity, VISTA cannot provide the time variation of relative blood flow velocity. Furthermore, in VISTA, it is necessary to adjust the scan parameters of the OCT scan according to the region of interest in order to acquire useful time analysis results. However, VISTA has no means to adjust the scan parameters while observing the region of interest in the object to be measured in real time. The present invention has been made in view of such circumstances, and one of objects of the present invention is to provide a new technique for acquiring time analysis result of VISTA for the object to be measured in real time. [MEANS OF SOLVING THE PROBLEMS] One aspect of embodiments is an analysis processing apparatus including: an acquisition unit configured to acquire two or more pieces of motion contrast data of a cross-section at interscan time intervals different from each other, the two or more pieces of motion contrast data being acquired by repeatedly performing B-scans three or more times on the same cross-section in an object to be measured; an analyzer configured to perform analysis processing for obtaining a time variation of a motion contrast intensity in the cross-section based on the two or more pieces of motion contrast data; and a display controller configured to cause an image representing the time variation obtained by performing the analysis processing to be displayed on a display means. Another aspect of the embodiments is an optical coherence tomography apparatus including: an optical system configured to perform optical coherence tomography on the obje