To present a rare cause of facial pain, and the differential diagnosis of a lesion of the mandibular division of the trigeminal nerve.

A 19-year-old woman presented to a tertiary referral skull base centre with right periorbital pain and a progressive, right-sided deficit of the mandibular division of the trigeminal nerve. Clinical examination revealed right-sided hypoaesthesia in the mandibular division of the trigeminal nerve dermatome, mild trismus and some wasting of the right masseter muscle. Computed tomography and magnetic resonance imaging scans revealed a small area of mildly enhancing soft tissue centred within the foramen ovale, with concentric enlargement. Surgery was undertaken via an infratemporal fossa (Fisch) type D approach. A vascular lesion was found filling the foramen ovale, with no obvious nerve separate from the lesion. The lesion was removed en bloc. Histopathological analysis demonstrated a venous haemangioma within the nerve.

Facial pain is common, and may be wrongly attributed to trigeminal neuralgia. A thorough clinical examination must be performed to identify subtle neurological abnormalities, and appropriate imaging undertaken to exclude rare causes, such as this venous haemangioma of the mandibular division of the trigeminal nerve.