Characteristics of Peripapillary Retinal Nerve Fiber Layer Thickness in Eyes With Myopic Optic Disc Tilt and Rotation

Abstract

Purpose: The purpose of the study was to investigate the effects of myopic optic disc tilt and rotation on peripapillary retinal nerve fiber layer (RNFL) thickness characteristics measured by Cirrus HD spectral-domain optical coherence tomography (Cirrus HD OCT). Methods: A total of 93 right eyes from 93 healthy young male individuals with myopia underwent ophthalmic examinations, including refractive error, axial length, and optic disc area measurements. The superior/inferior peak locations, RNFL thickness, and horizontal/vertical optic disc tilt were evaluated using the Cirrus HD OCT. The optic disc rotation was assessed by the angle between the long axis of the optic disc and the vertical meridian. The patients were divided into the tilted group and the non-tilted group; the tilted group was further divided into the rotated group and the nonrotated group. Results: The eyes in the tilted group (n = 47) had a greater axial length and thicker temporal RNFL and more temporally positioned superior/inferior peak locations than the non-tilted group (n = 46) (all P < 0.05). Among the eyes in the tilted group, the eyes in the rotated group (n = 23) had a thicker temporal RNFL and a more temporally positioned superior peak location than the eyes in the nonrotated group (n = 24) (all P < 0.05). Conclusions: The eyes with a myopic temporal optic disc tilt and counterclockwise rotation had a thicker temporal RNFL and more temporally positioned superior peak location. The characteristics of the RNFL thickness in eyes with myopic optic disc tilt and rotation should be considered when interpreting the RNFL thickness measured by the Cirrus HD OCT.