Anterior Chamber Angle Shape Analysis and Classification of Glaucoma in SS-OCT Images

Optical coherence tomography is a high resolution, rapid, and noninvasive diagnostic tool for angle closure glaucoma. In this paper, we present a new strategy for the classification of the angle closure glaucoma using morphological shape analysis of the iridocorneal angle. The angle structure configuration is quantified by the following six features: (1) mean of the continuous measurement of the angle opening distance; (2) area of the trapezoidal profile of the iridocorneal angle centered at Schwalbe's line; (3) mean of the iris curvature from the extracted iris image; (4) complex shape descriptor, fractal dimension, to quantify the complexity, or changes of iridocorneal angle; (5) ellipticity moment shape descriptor; and (6) triangularity moment shape descriptor. Then, the fuzzyknearest neighbor (fkNN) classifier is utilized for classification of angle closure glaucoma. Two hundred and sixty-four swept source optical coherence tomography (SS-OCT) images from 148 patients were analyzed in this study. From the experimental results, the fkNN reveals the best classification accuracy (99.11±0.76%) and AUC (0.98±0.012) with the combination of fractal dimension and biometric parameters. It showed that the proposed approach has promising potential to become a computer aided diagnostic tool for angle closure glaucoma (ACG) disease.

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Faculty Opinions recommendation of Vessel density and structural measurements of optical coherence tomography in primary angle closure and primary angle closure glaucoma.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.727368001.793536598 ◽

2017 ◽

Author(s):

Christopher Leung

Keyword(s):

Optical Coherence Tomography ◽

Angle Closure Glaucoma ◽

Vessel Density ◽

Angle Closure ◽

Optical Coherence ◽

Primary Angle Closure ◽

Primary Angle Closure Glaucoma

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The Use of Anterior-Segment Optical-Coherence Tomography for the Assessment of the Iridocorneal Angle and Its Alterations: Update and Current Evidence

Journal of Clinical Medicine ◽

10.3390/jcm10020231 ◽

2021 ◽

Vol 10 (2) ◽

pp. 231

Author(s):

Giacinto Triolo ◽

Piero Barboni ◽

Giacomo Savini ◽

Francesco De Gaetano ◽

Gaspare Monaco ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Intraocular Pressure ◽

Clinical Relevance ◽

Anterior Segment ◽

Angle Closure ◽

Current Evidence ◽

Optical Coherence ◽

Iridocorneal Angle ◽

Wide Range

The introduction of anterior-segment optical-coherence tomography (AS-OCT) has led to improved assessments of the anatomy of the iridocorneal-angle and diagnoses of several mechanisms of angle closure which often result in raised intraocular pressure (IOP). Continuous advancements in AS-OCT technology and software, along with an extensive research in the field, have resulted in a wide range of possible parameters that may be used to diagnose and follow up on patients with this spectrum of diseases. However, the clinical relevance of such variables needs to be explored thoroughly. The aim of the present review is to summarize the current evidence supporting the use of AS-OCT for the diagnosis and follow-up of several iridocorneal-angle and anterior-chamber alterations, focusing on the advantages and downsides of this technology.

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Atlas-based shape analysis and classification of retinal optical coherence tomography images using the functional shape (fshape) framework

Medical Image Analysis ◽

10.1016/j.media.2016.08.012 ◽

2017 ◽

Vol 35 ◽

pp. 570-581 ◽

Cited By ~ 15

Author(s):

Sieun Lee ◽

Nicolas Charon ◽

Benjamin Charlier ◽

Karteek Popuri ◽

Evgeniy Lebed ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Shape Analysis ◽

Optical Coherence

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Deep learning algorithms to isolate and quantify the structures of the anterior segment in optical coherence tomography images

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2019-315723 ◽

2020 ◽

pp. bjophthalmol-2019-315723

Author(s):

Tan Hung Pham ◽

Sripad Krishna Devalla ◽

Aloysius Ang ◽

Zhi-Da Soh ◽

Alexandre H Thiery ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Objective Assessment ◽

Anterior Segment ◽

Angle Closure Glaucoma ◽

Training Data ◽

Angle Closure ◽

Optical Coherence ◽

Segmentation Approach ◽

Reliable Quantification ◽

The Given

Background/AimsAccurate isolation and quantification of intraocular dimensions in the anterior segment (AS) of the eye using optical coherence tomography (OCT) images is important in the diagnosis and treatment of many eye diseases, especially angle-closure glaucoma.MethodIn this study, we developed a deep convolutional neural network (DCNN) for the localisation of the scleral spur; moreover, we introduced an information-rich segmentation approach for this localisation problem. An ensemble of DCNNs for the segmentation of AS structures (iris, corneosclera shell adn anterior chamber) was developed. Based on the results of two previous processes, an algorithm to automatically quantify clinically important measurements were created. 200 images from 58 patients (100 eyes) were used for testing.ResultsWith limited training data, the DCNN was able to detect the scleral spur on unseen anterior segment optical coherence tomography (ASOCT) images as accurately as an experienced ophthalmologist on the given test dataset and simultaneously isolated the AS structures with a Dice coefficient of 95.7%. We then automatically extracted eight clinically relevant ASOCT measurements and proposed an automated quality check process that asserts the reliability of these measurements. When combined with an OCT machine capable of imaging multiple radial sections, the algorithms can provide a more complete objective assessment. The total segmentation and measurement time for a single scan is less than 2 s.ConclusionThis is an essential step towards providing a robust automated framework for reliable quantification of ASOCT scans, for applications in the diagnosis and management of angle-closure glaucoma.

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