Effect of transposition of superior rectus muscle on vertical deviaton and cyclotropia

Abstract

Objective To analyze the effect of transposition of superior rectus muscle on vertical deviation and cyclotropia. Methods A prospective study. All 16 patients with ocular abduction dysfunction underwent superior rectus transposited to external rectus insertion. The degree of esotropia was measured with synoptophore, and the vertical deviation was measured with Maddox rod plus prism. The subjective cyclotropia was examined with the double Maddox, and the ocular rotation was evaluated objectively with fundus photography (fovea-disc angle, FDA). Results The difference of pre- and post-operative horizontal strabismus and limit of abduction and adduction were statistically significant, from pre-operative 35.00°±2.21° to post-operative 2.19°±0.78° (t=12.776, P=0.000), from -3.62±0.22 to -2.37±0.15 (t=-7.319, P=0.000), and from -0.06±0.06 to -2.12±0.15 (t=10.688, P=0.000). The vertical deviation was improved from 0.69△+ 0.50△ to 0.63△+ 0.73△ (t=0.083, P=0.935). The subjective cyclotropia were improved from 1.25°±0.50°to -0.69°±0.46° (t=3.422, P=0.004); the objective cyclotropia were improved from 8.93°±0.81°to 6.96°±1.08° (t=2.889, P=0.018). Conclusion Transposition of superior rectus muscle is an effective and safe method to treat ocular abduction dysfunction, which can correct esotropia, improve abduction limitation and restore a certain range of binocular single vision in primary position. Key words: Transposition, superior rectus muscle; Abduction nerve disease; Vertical deviation; Cyclotropia