Acute Cranial Nerve VI Palsy Following Prolonged Prone Positioning in an Adolescent With Neurofibromatosis Type 1: A Rare Complication of Spinal Surgery in the Prone Position

The abducens or sixth cranial nerve provides motor innervation to the lateral rectus muscle, which abducts the ipsilateral eye with secondary innervation of the contralateral medial rectus muscle to allow for coordinated movement of both eyes. Various acute and chronic pathologic conditions, most importantly pontine infarctions and increased intracranial pressure, can result in acute sixth cranial nerve palsies. We report the uncommon occurrence of acute abducens nerve palsy following spinal fusion surgery in an 18-year-old male patient with a history of multiple neurological and orthopedic conditions. Postoperatively, the patient presented with symptoms that included left diplopia with restricted upward and downward gaze, indicative of abducens nerve palsy. The anatomy of the sixth cranial nerve is discussed, potential etiologies of sixth nerve palsy presented, and a proposed diagnostic workup reviewed. Our report emphasizes the need for comprehensive exploration of ocular symptoms following spinal surgery, given the various potential etiologies of sixth nerve palsy.