Comparison of Cup-to-disc Ratio Using the Superfield Lens and Optical Coherence Tomography

ABSTRACT

PURPOSE: The author compared the effect of the cup-to-disc ratio using the Volk Superfield lens and optical coherence tomography (OCT) to evaluate its usefulness in glaucoma diagnosis and follow-up. METHODS: One hundred ninety-seven eyes of 100 patients were enrolled 34 normal, 75 glaucoma suspected, 43 normal tension glaucoma (NTG), 45 primary open angle glaucoma (POAG). Routine ophthalmic examinations, fundus examinations, and cup-to-disc ratio measurement using the Superfield lens after pupil dilatation, visual field test, OCT optic nerve head analysis, and OCT retinal nerve fiber layer analysis were performed. The author compared cup-to-disc ratio using the Superfield lens and OCT in normal, glaucoma suspected, normal tension glaucoma, and primary open angle glaucoma. RESULTS: Using the Superfield lens, the mean cup-to-disc ratio was 0.36+/-0.07 in normal eyes, 0.61+/-0.12 in suspected glaucoma, 0.75+/-0.11 in NTG, 0.70+/-0.17 in POAG. Using OCT, the mean cup-to-disc ratio was 0.58+/-0.13 in normal eyes, 0.69+/-0.12 in suspected glaucoma, 0.80+/-0.10 in NTG, and 0.76+/-0.15 in POAG. In all groups, cup-to-disc ratio using OCT were greater than using the Superfield lens and were statistically significant. CONCLUSIONS: Considering these differences in the clinical assessment of glaucoma, the combined use of the Superfield lens and OCT would be helpful in its diagnosis and follow-up.