Bilateral Abducent Nerve Palsy After Neck Trauma: A Case Report

INTRODUCTION: The abducent nucleus is located in the upper part of the rhomboid fossa beneath the fourth ventricle in the caudal portion of the pons. The abducent nerve courses from its nucleus, to innervate the lateral rectus muscle. This nerve has the longest subarachnoid course of all the cranial nerves, it is the cranial nerve most vulnerable to trauma. It has been reported that 1% to 2.7% of all head injuries are followed by unilateral abducent palsy, but bilateral abducent nerve palsy is extremely rare. CASE PRESENTATION: A 65-year-old woman presented to the emergency department following a motor vehicle accident. A neurological assessment showed the patient’s Glascow coma scale (GCS) to be 15. She complained of double vision, and we found lateral gaze palsy in both eyes. A hangman fracture type IIA (C2 fracture with posterior ligamentous C1 - C2 distraction) was found on the cervical CT scan. A three-month follow-up of the patient showed complete recovery of the abducent nerve. CONCLUSIONS: Conservative treatment is usually recommended for traumatic bilateral abducent nerve palsy. Our patient recovered from this condition after three months without any remaining neurological deficit, a very rare outcome in a rare case.