Corneal Biomechanics, Optic Disc Morphology, and Macular Ganglion Cell Complex in Myopia

Abstract

To determine the association between corneal biomechanical properties and optic disc morphology, to verify the relationship between corneal biomechanical properties and peripapillary retinal nerve fiber layer (pRNFL) thickness in myopia, and to investigate the association between axial length (AL) and pRNFL and macular inner retinal layer (MIRL) thickness in myopia. An observational cohort study was conducted. Corneal hysteresis (CH), corneal resistance factor, central corneal thickness (CCT), AL, MIRL thickness, and pRNFL thicknesses were measured. This study examined 100 eyes from 50 patients, age 33.48±8.32 years (mean±SD), with spherical equivalent ≤3 D. A multivariable mixed-model analysis adjusted by age and sex showed that CCT correlated negatively with disc area (P=0.002), rim area (P=0.007), cup area (P=0.01), cup/disc ratio (P=0.02), and cup volume (P=0.01). CH correlated negatively with disc area (P=0.03) and cup area (P=0.04). Neither CCT nor CH was correlated with pRNFL or MIRL. AL correlated negatively with the mean pRNFL (P=0.003), superior pRNFL (P=0.018), superiortemporal pRNFL (P=0.02), inferior pRNFL (P=0.033), and inferiornasal pRNFL (P=0.02), but not with MIRL. CCT and CH varied with optic disc morphology, but not with pRNFL or MIRL, in myopia. This relationship may relate to glaucoma risk in myopia. AL varied with pRNFL, primarily at the superior and inferior poles, but not with MIRL in myopia.