Journal of Clinical and Experimental Ophthalmology
Open Access

Abstract

Study of the Contour and the Excavation of the Optic Nerve Head

Rached Belgacem, Hédi Trabelsi, Ines Malek and Imed Jabri

Purpose: To extract the characteristic features of glaucoma automatically and early detection of the excavation of the cup inside papilla to identify the glaucomatous from non-glaucomatous to limit the disease progression.

Design: Perspective based on literature review and clinical expertise and analysis a set of clinical retinal fundus images for ophthalmology.

Methods: To automatically extract the disc, two methods making use of an edge detection circular Hough transform method and active contours are proposed in the paper. For the cup, excavation, inspection by histogram is used to automatically detect the cup.

Results: The value of cup-to-disc ratio CDR which is more than 0.50 is used to assess a patient as a glaucomatous case and the retina images analysis shows other features.

The features are automatically extracted as the area of the excavation, which has evolved over time, helps the ophthalmologist specify the severity of retinal disease.

Conclusion: The cup to disc ratio (CDR) and the area cup are important measures of the peril of the presence of glaucoma in an individual. In this study, we have presented an improvement method to calculate the CDR along vertical and horizontal axis automatically from fundus images of retina.

A set of 10 retinal images obtained from Tunisian glaucomatous patient, is used to assess the performance of the determined CDR to the clinical CDR, and it is found that our proposed method provides 98% accuracy in the determined CDR results and screening glaucoma.