Approach to Traumatic Sixth Nerve Palsy with Botulinum Toxin A

Abstract

Trauma is a frequent cause of acquired sixth nerve palsy in adults, either isolated or associated with other cranial nerve palsies and neurologic dysfunctions. The prognosis is rather good, but horizontal incomitance may become seriously disturbing^1.2 due to spastic contracture of the ipsilateral antagonist. Histological changes in paretic eye muscles have been shown to appear as early as three weeks after the onset of the cranial nerve palsy. Intramuscular injections of botulinum toxin A into the direct antagonist of the paretic muscle shortly after the onset of the palsy may help to prevent the development of spastic contracture of the ipsilateral antagonist and prevent restriction to abduction. It also assists to reestablish earlier the field of single binocular vision in primary position.

Key Words:

• Sixth nerve palsy
• trauma
• botulinum toxin A
• cavernous sinus fistula
• horizontal incomitance