Surgical management of large-angle incomitant strabismus in patients with oculomotor nerve palsy

ObjectiveTo evaluate the surgical options in treating strabismus caused by different degrees of oculomotor nerve palsy.MethodsSurgical procedures for 13 patients with unilateral oculomotor nerve palsy were retrospectively studied. Eight patients had partial paralysis with isolated or multiple muscle involvement. A greater amount of lateral rectus recession and medial rectus resection than is usual was performed in six cases; transposition combined with resection of the medial rectus was performed in two cases with limited hypotropia. Of five patients with total oculomotor nerve paralysis, three underwent transposition of the superior oblique tendon to the superior site of the medial rectus insertion. The other two patients, having total oculomotor nerve paralysis combined with trochlear nerve palsy, underwent fixation of the globe to the anterior lacrimal crest by half a tendon width of the medial rectus. Extremely large (10–12 mm) lateral rectus recessions were performed in all patients. Pre- and postoperative horizontal and vertical deviations were measured to assess the surgical outcomes.ResultsPreoperative deviations of the affected eye were exotropia of 80Δ to 120Δ, five cases with hypotropia of 15Δ to 35Δ, and two cases with hypertropia of 15Δ to 20Δ. After 6 to 27 months of postoperative follow-up, eye alignment showed horizontal residual deviation of 0Δ to 20Δ exotropia and vertical residual deviation of 4Δ to 10Δ hypotropia.ConclusionsBy choosing the appropriate surgical procedure, eye alignment in the primary position was achieved, but recurrence of the exotropia was unavoidable, and a residual exotropia of 10Δ to 20Δ remained in most patients.