Glaucoma diagnostic ability of quadrant and clock-hour neuroretinal rim assessment using cirrus HD optical coherence tomography

Abstract

Purpose: The aim of this study was to investigate the glaucoma diagnostic ability of quadrant and clock-hour neuroretinal rim assessment by Cirrus HD spectral-domain optical coherence tomography (OCT).

Methods: Eighty eyes of 80 glaucoma patients and 80 eyes of 80 healthy subjects were enrolled. Peripapillary retinal nerve fiber layer (RNFL) thickness was measured by Cirrus HD-OCT. Quadrant and clock-hour rim areas and thicknesses were obtained from optic nerve head images and 360° circumferential rim thickness curve of Cirrus HD-OCT, respectively. Area under receiver operating characteristic curves (AUCs) and sensitivities of RNFL thicknesses, rim areas, and rim thicknesses at a 90% specificity level were calculated.

Results: Quadrant and clock-hour rim area and thickness showed good diagnostic ability for glaucoma in all areas (AUCs, 0.877-0.969; sensitivities, 67.5%-96.3%). When the AUCs of RNFL thicknesses, rim areas, and rim thicknesses were compared, no significant difference was found in global area and superior and inferior quadrants (P > 0.05). However, in nasal and temporal quadrants, rim area and thickness had greater AUCs (AUCs, 0.919-0.945; sensitivities, 82.5%-86.3%) than RNFL thickness (AUCs, 0.749-0.776; sensitivities, 12.5%-33.8%; P < 0.001). Eyes with moderate to advanced glaucoma (mean deviation < -6 dB) had thinner RNFL than mild glaucoma (mean deviation ≥ -6 dB) in global area, superior, inferior, and temporal quadrants (P < 0.003); rim area and thickness showed no significant difference in all areas (P > 0.003).

Conclusions: Neuroretinal rim assessment in nasal and temporal areas by Cirrus HD-OCT may enhance glaucoma diagnostic ability. RNFL and rim changes measured by Cirrus HD-OCT may be different according to the stages of glaucomatous damage.