ABSTRACT
ABSTRACT: Purpose: To evaluate the effects of botulinum toxin-A as an alternate to surgery in acute complete sixth nerve palsy and to decrease the disease course. Materials and methods: 30 patients ranging from 9 mo to 70 yr with acute complete sixth nerve palsy received 2.5 units of botulinum toxin-A injection in the medial rectus muscle within one month from the onset of palsy. Toxin was injected directly into the muscle belly under local (25 cases) or general (5 cases) anesthesia. At the 1st, 7th, 30th, 90th and 180th day, binocular field, abduction and any residual deviation were measured. Results: 24(80%) patients had full abduction after 3 months and 6(20%) had 10° abduction. Among treatment failures, 3 were traumatic and 3 were tumoral. Binocular diplopia free field was 75° in 22(73%). 22(73%) had no residual esotropia although 8(27%) patients had 10-50° residual esotropia which required surgery. No cases of exotropia, or globe perforation was encountered. Conclusion: Injecting botulinum toxin-A is a simple and safe way of treating acute complete sixth nerve palsy and eliminating the need for invasive surgical manipulations.
