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CN-122004737-A - Household optical coherence tomography system

CN122004737ACN 122004737 ACN122004737 ACN 122004737ACN-122004737-A

Abstract

The invention relates to the technical field of coherence tomography, in particular to a household optical coherence tomography system which comprises a data acquisition module for acquiring an optical coherence tomography image of an eyeball and three-dimensional tomography data, a data dividing module for dividing the optical coherence tomography image into grids and determining an image quality index, a center positioning module for positioning a center point of a video disc based on a low-brightness communication area, a coordinate building module for screening qualified grids based on the image quality index and extracting a retina network characteristic point set to build a coordinate system, a coordinate verification module for projecting the three-dimensional tomography data onto a two-dimensional plane for carrying out coincidence comparison to verify the qualification of the coordinate system, a quality assessment module for determining whether the scanning quality is qualified or not based on a coordinate system verification result and the image quality index, and an optimization adaptation module for dynamically adjusting a preset threshold value to optimize the extraction of the characteristic point based on the quality assessment result. The method solves the technical problem that cross-time data cannot be accurately compared due to inconsistent scanning pose.

Inventors

  • LIU ZITIAN

Assignees

  • 中山大学中山眼科中心

Dates

Publication Date
20260512
Application Date
20251224

Claims (10)

  1. 1. A household optical coherence tomography system, comprising, A data acquisition module for acquiring an optical coherence tomographic image and three-dimensional tomographic data of an eyeball; The data dividing module is connected with the data acquisition module and is used for dividing the optical coherence tomography image into M multiplied by N regular rectangular grids and determining an image quality index based on the local contrast and the image entropy value of each grid; The center positioning module is connected with the data dividing module and is used for determining a video disc candidate area based on the comparison result of the pixel brightness average value of the low-brightness communication areas in the grids and the preset brightness threshold value, determining a unique video disc area based on the comparison result of the circularity of the video disc candidate area and the preset circularity, and calculating a geometric center point as a video disc center point; The coordinate establishing module is respectively connected with the data dividing module and the center positioning module, and is used for determining and extracting retina network characteristic point sets in a plurality of qualified grids based on the comparison result of the image quality indexes of the grids and the preset image quality indexes, and establishing a coordinate system with the video disc center points; The coordinate verification module is connected with the data acquisition module and the coordinate establishment module, and is used for projecting the retinal pigment epithelium layer based on three-dimensional tomographic data to a two-dimensional plane under the coordinate system, carrying out overlapping comparison with the retinal pigment epithelium layer of the optical coherence tomography image, and determining whether the coordinate system is qualified or not based on the comparison result of the overlapping ratio and a preset overlapping ratio threshold value; The quality evaluation module is respectively connected with the coordinate verification module and the data dividing module and is used for determining whether the scanning quality evaluation is qualified or not based on a verification result of whether the coordinate system is qualified or not and an image quality index; And the optimization adaptation module is respectively connected with the quality evaluation module, the coordinate verification module and the data division module and is used for determining and adjusting the preset image quality index threshold value or the preset coincidence degree threshold value to optimize the extraction of the scanned characteristic points based on the disqualification of the scanning quality evaluation and the disqualification of the coordinate system.
  2. 2. The home optical coherence tomography system of claim 1 wherein the data partitioning module determines an image quality index for each grid based on a weighted sum of local contrast and image entropy values for each grid.
  3. 3. The home optical coherence tomography system of claim 1 wherein said centering module determining a disc candidate region based on a low intensity connected region pixel intensity average comprises, Comparing the pixel brightness average value with a preset brightness threshold value; and determining the region as a video disc candidate region based on the pixel brightness average value being smaller than a preset brightness threshold value.
  4. 4. The home optical coherence tomography system of claim 1 wherein said centering module determines a unique disc region based on the circularity of the disc candidate region is, Comparing the circularity with a preset circularity; And determining the area as the unique optic disc area based on the circularity being greater than or equal to a preset circularity.
  5. 5. The home optical coherence tomography system of claim 1 wherein said coordinate establishment module determining a qualified grid comprises, Comparing the image quality index with a preset image quality index; determining that the grid is a qualified grid based on the image quality index being greater than or equal to a preset image quality index; and determining that the grid is a disqualified grid based on the fact that the image quality index is smaller than a preset image quality index.
  6. 6. The home optical coherence tomography system of claim 1, wherein the coordinate validation module determines whether the coordinate system is acceptable based on a comparison of the degree of coincidence with a preset degree of coincidence threshold value comprises, Comparing the contact ratio with a preset contact ratio threshold value; determining that the coordinate system is qualified based on the fact that the contact ratio is greater than or equal to the preset contact ratio threshold value; and determining that the coordinate system is disqualified based on the fact that the contact ratio is smaller than the preset contact ratio threshold value.
  7. 7. The home optical coherence tomography system of claim 1 wherein said quality assessment module determining whether a scan quality assessment is acceptable comprises, Determining that the scanning quality evaluation is qualified based on the coordinate system being qualified and the image quality index being greater than or equal to a preset quality index threshold; And determining that the scanning quality evaluation is not qualified based on the condition that the coordinate system is not qualified or the image quality index is smaller than a preset quality index threshold.
  8. 8. The home optical coherence tomography system of claim 1 wherein the optimization adaptation module determines to decrease the preset overlap threshold by a first adjustment factor based on coordinate system failure.
  9. 9. The home optical coherence tomography system of claim 1 wherein said optimization adaptation module determines to decrease said preset image quality index threshold by a second adjustment factor based on scan quality failure.
  10. 10. The home optical coherence tomography system of claim 1, wherein the optimization adaptation module determines to simultaneously reduce the preset overlap ratio threshold and the preset image quality index threshold by a third adjustment factor based on the coordinate system being failed and the scan quality being failed.

Description

Household optical coherence tomography system Technical Field The invention relates to the technical field of coherence tomography, in particular to a household optical coherence tomography system. Background With the aggravation of the aging trend of population and the general increase of the service time of electronic screens, the incidence rate of chronic eye diseases such as glaucoma, age-related macular degeneration and the like is continuously increased, and the vision impairment caused by the diseases is irreversible, thus the social medical burden and the personal life quality are seriously threatened. Optical Coherence Tomography (OCT) technology is used as a gold standard for current fundus disease diagnosis, can realize micron-scale resolution imaging of retina structures, and provides possibility for early diagnosis. However, conventional OCT devices are bulky, specialized in operation, and expensive, and must rely on specialists to perform operations and interpretation within a medical facility, which makes them inapplicable to high frequency daily monitoring in a home environment. Patients often need to review once every month or even half a year, which is highly likely to miss early dry expectations for chronic eye diseases requiring lifelong monitoring, with hidden disease progression. Chinese patent publication No. CN113940623a discloses a binocular optical coherence tomography imaging system for simultaneously imaging a region of a first eye (110) and a second eye (120) using an interferometer having a reference arm (170), a first sampling arm (150) and a second sampling arm (160) by obtaining an electrical signal (S) having a first frequency component and a second frequency component, the first frequency component spanning a first frequency band and being caused by interference between reference light in the reference arm and light in the first sampling arm reflected from the first eye, the second frequency component spanning a second frequency band and being caused by interference between reference light and light in the second sampling arm reflected from the second eye, and generating an OCT image of the region of the first eye using the first frequency component in a portion of the first frequency band that does not overlap with the second frequency band, and generating an OCT image of the region of the second eye using the second frequency component in a portion of the second frequency band that does not overlap with the first frequency band. It follows that the binocular optical coherence tomography imaging system has the following problems: The unified coordinate system for cross-time data comparison cannot be constructed, namely the problem of data dislocation caused by the difference of eyeball positions and gaze angles during each self-help scanning of a user cannot be solved, so that the scanning data acquired at different time points cannot be directly comparable. Disclosure of Invention Therefore, the invention provides a household optical coherence tomography system, which is used for solving the problem that in the household optical coherence tomography system in the prior art, cross-time data cannot be accurately compared due to inconsistent scanning positions. To achieve the above object, the present invention provides a home optical coherence tomography system, comprising, A data acquisition module for acquiring an optical coherence tomographic image and three-dimensional tomographic data of an eyeball; The data dividing module is connected with the data acquisition module and is used for dividing the optical coherence tomography image into M multiplied by N regular rectangular grids and determining an image quality index based on the local contrast and the image entropy value of each grid; The center positioning module is connected with the data dividing module and is used for determining a video disc candidate area based on the comparison result of the pixel brightness average value of the low-brightness communication areas in the grids and the preset brightness threshold value, determining a unique video disc area based on the comparison result of the circularity of the video disc candidate area and the preset circularity, and calculating a geometric center point as a video disc center point; The coordinate establishing module is respectively connected with the data dividing module and the center positioning module, and is used for determining and extracting retina network characteristic point sets in a plurality of qualified grids based on the comparison result of the image quality indexes of the grids and the preset image quality indexes, and establishing a coordinate system with the video disc center points; The coordinate verification module is connected with the data acquisition module and the coordinate establishment module, and is used for projecting the retinal pigment epithelium layer based on three-dimensional tomographic data to a two-dimensional plane under