Relative peripheral refraction in patients with horizontal strabismus

Abstract

Purpose: To determine whether relative peripheral refraction (RPR) in strabismic children is different from that in normal children.

Methods: We recruited 25 consecutive patients with comitant horizontal strabismus (mean ± SD age, 10.1 ± 2.6 years) as subjects and 37 children who had no ophthalmic disease except for refractive errors as controls. Cycloplegic refraction was performed with an autorefractometer while the subjects looked at one of five targets horizontally aligned within ± 30°. RPR was calculated by subtracting refraction in the primary position from that obtained at each gaze position.

Results: Children with either esotropia or exotropia had small myopic RPR on average, whereas the controls showed significant hyperopic RPR. In children with exotropia, a wide intersubject difference in RPR was found in the nasal retina. These profiles of RPR were observed in both dominant and nondominant eyes.

Conclusions: The results of this study indicate that children with horizontal strabismus have different RPR than normal controls. Defocus in the peripheral retina associated with the misalignment of the eyes during near work might be the reason for the differences, considering the visual regulation mechanism of eye shape.