Investigating the Prevalence of astigmatism in Patients with Intermittent Exotropia in Egyptian children

Uncorrected refraction is the major cause of visual morbidity among children and can result in the development of strabismus. Although several studies have investigated the risk factors for intermittent exotropia, uncorrected astigmatism, which is critical for prevention and treatment, has not been well estimated. Objectives: To evaluate the association between uncorrected astigmatism and intermittent exotropia in children. Methods: This retrospective, analytical, cross-sectional, population-based study included 90 children with intermittent exotropia X(T) who were followed up for two years; the children were aged from 6 to 12 years old. Patients were retrospectively reviewed to determine the prevalence of astigmatism and amblyopia accompanied by X(T). Data were recorded, including visual acuity measurements, manifest refraction, eye examinations, and strabismus examination. Results: There was a significant correlation between uncorrected myopic astigmatism and intermittent exotropia; however, no correlation was found between the angle of deviation in intermittent exotropia and cylindrical diopters. There was a progressive reduction in the angle of deviation for intermittent exotropia after correction for myopic astigmatism. A significant correlation exists between uncorrected myopia and intermittent exotropia; however, there is no correlation between the angle of deviation in X(T) and the diopteric power of myopia. Conclusion: Intermittent exotropia and uncorrected myopic astigmatism are strongly correlated. The younger the patient with X(T) who has corrected refractive error, the better the fusional control and reduction in the angle of deviation of intermittent exotropia.