Objective and importance: We describe a patient with a cavernous malformation within the trigeminal nerve at the nerve root entry zone who presented with trigeminal neuralgia.
Clinical presentation: A 52-year-old woman sought treatment after experiencing dizziness and lancinating left facial pain for almost a year. Neurological examination revealed diminished sensation in the distribution of the trigeminal nerve on the left. Magnetic resonance imaging demonstrated a minimally enhancing lesion affecting the trigeminal nerve.
Intervention: The patient underwent a retrosigmoid craniotomy. At the nerve root entry zone, the trigeminal nerve was edematous with hemosiderin staining. The lesion, which was resected with microsurgical technique, had the appearance of a cavernous malformation on gross and histological examination. The patient's pain improved significantly after resection.
Conclusion: Cavernous malformations can afflict the trigeminal nerve and cause trigeminal neuralgia. Microsurgical excision can be performed safely and is associated with improvement in symptoms.