Angle closure glaucoma detection using fractal dimension index on SS-OCT images

Optical coherence tomography (OCT) is a high resolution, rapid and non-invasive screening tool for angle closure glaucoma. In this paper, we propose a new strategy for automatic and landmark invariant quantification of the anterior chamber angle of the eye using swept source optical coherence tomography (SS-OCT) images. Seven hundred and eight swept source optical coherence tomography SS-OCT images from 148 patients with average age of (59.48 ± 8.97) were analyzed in this study. The angle structure is measured by fractal dimension (FD) analysis to quantify the complexity or changes of angle recess. We evaluated the FD index with biometric parameters for classification of open angle and angle closure glaucoma. The proposed fractal dimension index gives a better representation of the angle configuration for capturing the nature of the angle dynamics involved in different forms of open and closed angle glaucoma (average FD (standard deviation): 1.944 (0.045) for open and 1.894 (0.043) for closed angle). It showed that the proposed approach has promising potential to become a computer aided diagnostic tool for angle closure glaucoma (ACG) disease.