Asymmetrical folding of the anterior portion of the superior oblique muscle is a simplified variant of the Harada-Ito procedure that is supposed to selectively correct ocular torsion.
This surgical technique was applied to 22 patients suffering from bilateral acquired IV nerve palsy. Ocular torsion was evaluated with the Harms tangent screen. Pre- and post-operative torsional values were compared. Post-operative follow-up was 12 months.
Pre-operatively, mean excyclotropia was 8.8 degrees in primary position and 15.9 degrees in downgaze. Post-operatively, these values decreased to 1.5 degrees and 4.1 degrees, respectively. An enlarged field of binocular single vision, extending beyond 10 degrees inferiorly, was obtained in 17/22 patients.
The selective technique of superior oblique muscle anterior tendon tucking allows one to efficiently correct the ocular torsion induced by acquired bilateral IV nerve palsy.