Intrinsic arteriovenous malformation of the trigeminal nerve in a patient with trigeminal neuralgia: case report

Abstract

Objective and importance: Intrinsic arteriovenous malformation (AVM) of the trigeminal nerve is extremely uncommon and may be associated with trigeminal neuralgia.

Clinical presentation: A 55-year-old man experienced severe lightning pain in the second and third divisions of the left trigeminal nerve territory. Vertebral angiography demonstrated an AVM fed by the superior cerebellar artery. Magnetic resonance imaging with three-dimensional spoiled gradient recalled acquisition at steady state revealed an AVM intrinsic to the left trigeminal nerve and a small arterial loop causing compression at the root entry zone of the trigeminal nerve.

Intervention: Intraoperative inspection revealed an indentation of the root entry zone caused by a small arterial loop but not by the AVM. The offending artery was displaced to decompress the root entry zone using a prosthesis without resection of the AVM. The patient was relieved of the neuralgia immediately after surgery without further neurological deficit. He has been free of trigeminal neuralgia during a follow-up period of 2 years and is scheduled to undergo stereotactic radiosurgery for the treatment of the AVM.

Conclusion: Intrinsic AVM of the trigeminal nerve may cause trigeminal neuralgia. However, as in the present case, a coexistent vascular lesion rather than the intrinsic AVM could be a cause of the neuralgia.