Partial third cranial nerve palsy: Clinical characteristics and surgical management

Purpose: Incomplete recovery from injury to the third cranial nerve results in ocular misalignment and associated diplopia. Our aim in this study was to describe and evaluate strabismus surgery strategies aimed at restoring functional, single binocular vision in this population. Design: Retrospective review. Participants: We studied 12 adult patients with acquired partial third cranial nerve palsy who underwent strabismus surgery. Methods: The 12 consecutive patients with residual third nerve palsy were selected from among the patients seen between 2000 and 2010 in the clinical practice of 1 strabismologist (M.F.). Complete pre- and postoperative ophthalmologic and orthoptic examinations were performed in each patient. The patients presented with isolated hypotropias (n = 7) and exohypotropias (n = 5). Strabismus surgery included: contralateral superior rectus recession, ipsilateral inferior rectus recession, vertical transposition of horizontal recti, horizontal rectus muscle surgery, or combined horizontal and vertical muscle surgery. Complete surgical success was defined as postoperative alignment within 5 prism diopters (PD) of orthotropia and the absence of diplopia in functional positions of gaze. The average follow-up was 23 months (range, 7 to 81 months). Results: The mean preoperative vertical and horizontal deviations were 19 PD hypotropia (8-40 PD) and 19 PD exotropia (6-40 PD), respectively. The mean postoperative deviations were 2 PD hypotropia (0-8 PD) and 1 PD exotropia (0-6 PD). Complete surgical success was achieved in 7 of 12 patients. Partial success was attained in 5 of 12 patients, who experienced significant improvement but required postoperative use of a prism. Conclusions: This study indicates that patients with incomplete third cranial nerve paralysis may enjoy good functional and cosmetic outcomes with strabismus surgery.