Prevalence of strabismic binocular anomalies, amblyopia and anisometropia. Rehabilitation Faculty of Shahid Beheshti Medical University

Abstract Purpose Manifest strabismus such as constant and alternative esotropia and exotropia, not only cause cosmetic problem in patients but also induce disorders such as amblyopia. These anomalies can lead to academic failure in students and reduce efficiency in other jobs. Therefore, determining the prevalence of binocular anomalies is important. The purpose of this study is to determine the prevalence of strabismic binocular anomalies, amblyopia and anisometropia in patients examined in optometry clinic of the rehabilitation faculty of Shahid Beheshti Medical University in 2008/2009. Methods In this study, files of 600 patients were evaluated. Cycloplegic refraction was performed in infants, elementary and middle school children and other patients had noncylcoplegic refraction. Anisometropia was defined as a difference of 1.00D or more between two eyes. Amblyopia was diagnosed as a reduction of best corrected visual acuity (BCVA) to 20/30 or less in one eye or 2-line difference in the absence of pathological causes. Cover test was performed to investigate of strabismus. Results The prevalence of strabismic binocular anomalies, amblyopia and anisometropia were respectively: anisometropia in 64 patients (10.67%), anisometropic amblyopia in 9 patients (1.5%), anisometropic amblyopia with exotropia in 1 patient (0.17%), anisometropic amblyopia with esotropia in 1 patient (0.17%), bilateral amblyopia in 5 patients (0.83%), esotropia in 2 patients (0.33%), exotropia in 1 patients (0.17%) and convergence insufficiency in 2 patients (0.33%). Discussion The results show that the prevalence of anisometropia was higher than shown in previous studies but prevalence of convergence insufficiency, esotropia and exotropia was lower than previous studies.