Peripapillary Retinal Nerve Fiber Layer Thickness Variations with Myopia
Received 4 June 2005; accepted 26 January 2006.
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 × 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 1.75×VDD (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 1.75×VDD (r = −0.02, P = 0.78) scan diameters. Mean peripapillary RNFL thicknesses for the 3.40-mm, 4.50-mm, and 1.75×VDD scans were 101.1±8.2 μm (95% confidence interval [CI], 99.4–102.8), 78.9±8.2 μm (95% CI, 77.5–80.3), and 97.5±10.9 μm (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.
1Singapore National Eye Centre & Singapore Eye Research Institute, Singapore
2Defence Medical & Environmental Research Institute, Singapore
ABSTRACT