Full-tendon inferior nasal transposition of the lateral rectus muscle for partial third nerve palsy

Abstract

Managing third nerve palsy clinically can be challenging because it involves four of the six extraocular muscles. The palsy may be partial or complete, may cause partial or complete ptosis, and may spare or involve the pupil. A 25-year-old female with a history of suprasellar schwannoma had left partial third nerve palsy with 80 prism diopter (PD) exotropia and 20 PD hypertropia. In addition, adduction and infraduction of the left eye were limited. To address this, a lateral rectus (LR) muscle transposition procedure was performed, wherein the muscle was transposed between the inferior rectus muscle and the globe, passing behind the inferior oblique muscle and extending to the lower margin of the medial rectus (MR) muscle. Postoperatively, this procedure corrected the exotropia of 50–60 PD and hypertropia of 20 PD without inducing cyclotropia. Full-tendon transposition of the LR to the MR is a simple and effective procedure for managing partial third nerve palsy.