A study to evaluate and compare the effect of amblyopia on both nerve fiber layer thickness and ganglion cell complex in either anisometropic or strabismic individuals

Abstract

Background Anisometropia and high refractive errors are very annoying problems. Anisometropic amblyopia is one of the most common forms of amblyopia. Typical treatment includes refractive correction with glasses or contact lenses combined with occlusion. Anisometropic amblyopia is often detected later than other forms of amblyopia, because vision is generally good in the fellow eye, the eyes are typically orthotropic, and the child functions well with the use of the sound eye. A large fraction of the cases results from strabismus with constant unilateral fixation, which leads to amblyopia in the deviating eye. Amblyopia generally does not develop if fixation alternates, providing each eye with similar access to higher visual centers, or if strabismic deviation is intermittent (as a result of fusional vengeance or incomitance), so that there are periods of normal binocular interaction that preserve the integrity of the visual system. The visual system is sensitive to the effects of abnormal visual experience only during a limited time in infancy and childhood; this is referred to as the critical period or the sensitive period. Objective This study used SD-optical coherence tomography to compare retinal nerve fiber layer (RNFL) thickness and ganglion cell complex in amblyopic and fellow eyes of patients of varied ages. Twenty patients (10 patients with anisometropic amblyopia and 10 patients with strabismic amblyopia) with unilateral amblyopia underwent SD-optical coherence tomography examination for both amblyopic and follow eyes. Results and conclusion The study showed that there was no significant difference in RNFL between amblyopic and fellow eyes in the two groups of anisometropic and strabismic amblyopia. There was a statistically significant difference in ganglion cell complex thickness measurements between amblyopic eyes and fellow eyes in the two groups of anisometropic and strabismic amblyopia. There was a statistically significant difference between the two groups of patients regarding means of average RNFL thickness in the fellow eyes and means of inferior RNFL thickness in the fellow eyes.