Retinal Nerve Fiber Layer Thickness in Amblyopic Eyes

PurposeTo compare the peripapillary retinal nerve fiber layer (RNFL) thickness of amblyopic and fellow eyes. We hypothesized that the RNFL of the amblyopic eye may be thinner.DesignProspective, cross-sectional, observational case series.MethodsOptical coherence tomography of the peripapillary RNFL thickness of amblyopic and fellow eyes was performed in 37 patients 7 to 12 years of age (mean age ± standard deviation, 9.2 ± 1.5 years) with unilateral strabismic, anisometropic, or combined-mechanism amblyopia enrolled in a randomized treatment trial.ResultsMean global RNFL thickness of the amblyopic and fellow eyes was 111.4 and 109.6 μm, respectively (mean difference, 1.8 μm thicker in the amblyopic eyes; 95% confidence interval, −0.6 to 4.3 μm). The amblyopic eye was 8 μm or more thicker than the fellow eye in 9 patients (24%); the fellow eye was 8 μm or more thicker than the amblyopic eye in 2 patients (5%); and the difference was within test–retest variability (7 μm) in 26 patients (70%).ConclusionsOur findings do not indicate that peripapillary RNFL thickness is thinner in eyes with moderate amblyopia compared with their fellow eyes.