Prevalance of glaucoma and optical coherence tomography findings in subjects with optic nerve head excavation diagnosed during routine eye examination

SUMMARYThis study is aimed to determine (1) the prevalence of glaucoma, (2) the association ofthe presence of glaucoma with demographic and ocular characteristics and (3) opticalcoherence tomography (OCT) findings in subjects with a cup-to-disc (C/D) ratio equal to orgreater then 0.5 that diagnosed during routine eye examination.A total of 468 eyes of 235 subjects with a negative history of glaucoma and with aC/D ratio ≥ 5/10 that established during routine eye examination in the OphthalmologyDepartment of Gazi University Medical Faculty and 90 eyes of 45 normal subjects (controlgroup) with a C/D ratio ≤ 4/10 were included in this study. Patients underwent a completeophthalmic examination, diurnal intraocular pressure measurement, gonioscopy, centralcorneal thickness (CCT), axial length (AL), OCT optic nerve head (ONH) and retinal nervefiber layer (RNFL) analysis and visual field (VF) testing examinations.There were 114 (48.5%) men and 121 (51.5%) women within the study group. VFtesting results showed the presence of different stages of perimetric glaucoma in 52 out of 235subjects (22%). The mean age of patients with glaucoma and physiological cupping (PC)were 59.11 ± 13.95 and 46.83 ± 15.67, respectively with a significant statistical difference(p=0,000). There were no statistical differences among CCT, AL or refractive status betweentwo groups (p=0,880, p=0,192 ve p=0,797).Careful ONH examination is very important for diagnosis of glaucoma during routineeye examination. The prevalence of glaucoma among subjects with a C/D ratio ≥ 5/10 isfound to be 22%. The most important demographical characteristic of glaucoma prevalenceamong these subjects is shown to be increasing age. Prevalence is 8.4% in subjects aged lessthan 50 years old and 34% in subjects aged older than 51 years old. The best OCT parameteris found to be the average RNFL thickness in discriminating between glaucoma and FC eyes.