Optic Disc and Retinal Nerve Fiber Layer Parameters of Eyes With Keratoconus

Abstract

BACKGROUND AND OBJECTIVE: To evaluate optic nerve head (ONH) characteristics and retinal nerve fiber layer (RNFL) thickness measurements in patients with nonglaucomatous keratoconus. PATIENTS AND METHODS: This was a cross-sectional, observational study in which 46 patients with keratoconus and 74 healthy subjects were included. Analysis of ONH and RNFL imaging were performed by confocal scanning laser ophthalmoscopy and optical coherence tomography, respectively. RESULTS: Eyes with keratoconus had larger disc area (2.37 ± 0.5 vs 2.17 ± 0.36 mm(2)) (P = .013), larger cup area (0.65 ± 0.53 vs 0.49 ± 0.28 mm(2)) (P = .035) and deeper cup depths (for mean cup depth 0.24 ± 0.09 vs 0.20 ± 0.07 mm, P = .008 and for maximum cup depth 0.69 ± 0.27 vs 0.60 ± 0.17 mm, P = .037) than control group eyes. Height variation contour also differed in the two groups (P = .007) but RNFL measurements did not. CONCLUSION: RNFL thickness between patients with keratoconus and healthy subjects seems to be more comparable than ONH parameters.