Peripapillary retinal nerve fiber layer thickness variations with myopia

Abstract

Purpose: To determine the relationship between peripapillary retinal nerve fiber layer (RNFL) thickness and myopia using optical coherence tomography (OCT).

Design: Prospective observational case series.

Methods: One hundred thirty-two young males with myopia (spherical equivalent [SE], -0.50 to -14.25 diopters) underwent ophthalmic examination of one randomly selected eye. Optical coherence tomography (OCT-1, version 4.1) was performed by a single operator using circular scans concentric with the optic disc with scan diameters of 3.40 mm, 4.50 mm, and 1.75 x vertical disc diameter (VDD). For each scan diameter, mean peripapillary RNFL thickness was calculated. Statistical analysis comprised repeated-measurements analysis and Pearson correlation.

Results: Mean peripapillary RNFL thickness did not correlate with SE for the 3.40-mm (r = -0.11, P = 0.22), 4.50-mm (r = -0.103, P = 0.24), or 1.75xVDD (r = -0.08, P = 0.36) OCT scan diameters. Neither did mean peripapillary RNFL thickness correlate with axial length for the 3.40-mm (r = -0.04, P = 0.62), 4.50-mm (r = 0.03, P=0.75), or 1.75xVDD (r = -0.02, P = 0.78) scan diameters. Mean peripapillary RNFL thicknesses for the 3.40-mm, 4.50-mm, and 1.75xVDD scans were 101.1+/-8.2 microm (95% confidence interval [CI], 99.4-102.8), 78.9+/-8.2 microm (95% CI, 77.5-80.3), and 97.5+/-10.9 microm (95% CI, 95.6-99.4), respectively.

Conclusions: Mean peripapillary RNFL thickness did not vary with myopic SE or axial length for any OCT scan diameter investigated. Retinal NFL thickness measurements may be a useful parameter to assess and monitor glaucoma damage in myopic subjects.