A New Surgical Treatment Option for Chronic Total Oculomotor Nerve Palsy: A Modified Technique for Medial Transposition of Split Lateral Rectus Muscle

Abstract To describe a new surgical modified procedure in patients with chronic total oculomotor nerve palsy and to evaluate the results of this procedure. Eight eyes of 6 consecutive patients who underwent strabismus surgery due to chronic total oculomotor nerve palsy were enrolled in the study. The lateral rectus muscle was split into two halves and disinserted from the sclera. The upper half of the muscle was passed under the superior rectus muscle and the inferior half of the muscle was passed under the inferior rectus muscle. The two halves of the muscle were moved to the medial rectus muscle insertion area and were sutured to sclera near the insertion. Additional medial rectus resections were made in the undercorrected patients. The mean age was 21.8 ± 12.1 years (range: 11 to 42 years). Postoperatively, 4 of 6 patients had stable horizontal deviations; 1 had orthophoria, 2 had 10 prism diopters (PD) of exotropia, and 1 had 10 PD of esotropia. However, 2 cases had 25 and 30 PD of undercorrection. Additional medial rectus resections were made in these undercorrected patients and horizontal deviations reduced to 15 and 20 PD of exotropia, respectively. The mean primary position horizontal deviation, which was 74.1 ± 10.2 PD before the surgeries, reduced to 10.8 ± 6.6 PD after the surgeries (P