The role of Botulinum toxin in management of acute traumatic third-nerve palsy.

Purpose: To study the effect of botulinum toxin A injection in the management of paralytic exotropia resulting from acute traumatic third (oculomotor) nerve palsy.

Methods: Nine patients with acute traumatic partial third-nerve palsy of less than 2 months' duration were treated by injection of botulinum toxin A into the ipsilateral lateral rectus muscle. The horizontal deviation angles before and after the injections were recorded. A distance exotropia of less than 10(Delta) or absence of diplopia in the primary position at the last follow-up was defined as recovery.

Results: The mean preinjection deviation in the primary position was 48.3(Delta) of exotropia, and the mean postinjection deviation in the primary position was 14.2(Delta) at the last follow-up. Seven patients experienced recovery and regained single binocular vision in the primary position. The overall recovery rate was 77.8%. Two patients did not recover and subsequently underwent strabismus surgery.

Conclusions: Patients with acute traumatic partial third-nerve palsy treated by injection of botulinum toxin A in the lateral rectus muscle showed marked recovery when injection was performed within 2 months of the onset of palsy. Botulinum toxin injection into the lateral rectus muscle may provide temporary relief of symptoms in some patients and seems to be a useful treatment option in cases of acute traumatic third nerve palsy in the short-term.