Lateral Rectus Myectomy Combined With Medial Rectus Plication for Complete Oculomotor Nerve Palsy: A Case Report With
Yuna Irie1,2, Kie Iida1, Kazusa Kuwano1
1Department of Ophthalmology, The Jikei University School of Medicine, Minato-ku, Tokyo, Japan, jikei.ac.jp.
Background:
Lateral rectus myectomy has been reported as an effective and simple surgical option for large-angle paralytic exotropia. We report a case of complete oculomotor nerve palsy treated with lateral rectus myectomy combined with medial rectus plication, focusing on serial changes in ocular alignment and abduction limitation.
Case Report:
A woman in her 20s developed left oculomotor nerve palsy following surgery for an intracranial tumor. At presentation, visual acuity was 20/16 and 20/100, with temporal hemianopia and a central scotoma in the right and left eyes, respectively. She exhibited severe left exotropia exceeding 100 prism diopters (Δ), consistent with complete oculomotor nerve palsy, with a marked limitation of adduction graded as -7. Lateral rectus myectomy and 10 mm medial rectus plication were performed on the left eye. The lateral rectus muscle was resected 10 mm posterior to its insertion, and the distal stump was cauterized and allowed to retract into the posterior Tenon's capsule, intentionally creating a lost muscle. On Postoperative Day 1, ocular alignment improved to 18 Δ of esotropia with severe limitation of abduction graded as -4. From 2 months postoperatively, abduction limitation gradually decreased to -2 at 4 months, concomitant with the gradual recurrence of exotropia, after which both findings remained stable. Orbital MRI performed 5 months postoperatively demonstrated posterior reattachment of the lateral rectus muscle via fibrous tissue. At final follow-up, ocular alignment stabilized at 30 Δ of exotropia.
Conclusions:
Combined lateral rectus myectomy and medial rectus plication achieved a substantial corrective effect for large-angle paralytic exotropia due to oculomotor nerve palsy. While this technique represents a safe and effective treatment option, postoperative recurrence may occur due to reattachment of the resected lateral rectus muscle to the globe or orbital pulley, highlighting the need for long-term follow-up.
