Effect of Photorefractive Keratectomy on Nystagmus and Visual Functions in Myopic Patients With Infantile Nystagmus Syndrome

Abstract

To determine the effect of photorefractive keratectomy (PRK) on involuntary eye movements, visual acuity, and contrast sensitivity in myopic patients with infantile nystagmus syndrome. Prospective interventional case series. This study was conducted on patients with infantile nystagmus syndrome and myopia equal to or more than-1 diopter (D), who were referred to our clinic over a 2-year period. Patients older than 18 years of age with a stable refraction for at least 1 year who were good candidates for PRK were included. Complete ophthalmologic examinations including assessment of best-corrected visual acuity (BCVA), contrast sensitivity, and videonystagmography were performed for all patients before and 3months after surgery. Twenty-four eyes of 12 patients with mean age of 23 ± 2 years were enrolled in this study. Spherical equivalent refractive error was-2.82 ± 1.65 D and-0.26 ± 0.25 D before and after PRK, respectively (P < .001). Monocular BCVA improved from 0.36 ± 0.21 logMAR to 0.27 ± 0.25 logMAR and binocular BCVA improved from 0.33 ± 0.2 logMAR to 0.17 ± 0.16 logMAR (P < .001). Contrast sensitivity significantly improved at low (P < .001), intermediate (P<.001), and high frequencies (P= .01). The frequency, amplitude, and intensity of nystagmus were significantly decreased after PRK (P < .001). There was no correlation between the degree of myopia correction and improvement in sensory and motor indicesof nystagmus (P > .1, Spearman correlation coefficient). PRK in patients with infantile nystagmus syndrome and myopia improved monocular and binocular BCVA and contrast sensitivity. Furthermore, motor indices of nystagmus (frequency, amplitude, and intensity) were significantly improved after surgery in these patients.