ABSTRACT

Evaluation of the thicknesses of medial and lateral rectus muscles with magnetic resonance imaging in patients with horizontal strabismus: the effect of amblyopia We aimed to investigate the effect of amblyopia on the thicknesses of medial and lateral rectus muscles in patients with concomitant horizontal strabismus. Thicknesses of medial and lateral muscles of 73 patients who had concomitant horizontal strabismus and were being followed by the Pediatric Ophthalmology and Strabismus Unit of Gülhane Military Medical Academy were measured on primary gaze position with magnetic resonance imaging with two-mm slice thickness on T1-weighted axial slices. Differences between the patients who had and who did not have amblyopia were evaluated statistically. The mean diameter of lateral rectus muscle in patients with amblyopia and esotropia (1.33±0.38 mm) was significantly thinner than the mean diameter of lateral rectus muscle in patients with esotropia and without amblyopia (2.05±0.74 mm) (p=0.007). The mean diameter of lateral rectus muscle in patients with amblyopia and exotropia (3.38±1.27 mm) was significantly thicker than the mean diameter of lateral rectus muscle in patients with exotropia and without amblyopia (1.91±0.8 mm) (p<0.001). There were no statistically significant differences between the mean diameters of medial rectus and lateral rectus muscles in patients with either esotropia or exotropia but without amblyopia. Prominent changes occur in horizontal rectus muscles in the presence of amblyopia in patients with horizontal concomitant strabismus.