Trigeminal Neuropathy Accompanied by a Pontine Lesion on MRI.

A 63-year-old man presented with the loss of the sensations of pain and temperature sensation in the right facial region innervated by the trigeminal nerve (V1 to 3). He showed abnormal lesions in the pons and the trigeminal nerve on magnetic resonance imaging (MRI). He had recurrent herpes in the nasal cavity, and a history of left facial palsy. We herein present the unique MRI findings and suggest that herpes simplex infection may cause trigeminal neuropathy. This is the first reported case of dissociated trigeminal neuropathy with herpes simplex infection which was accompanied by a pontine lesion on MRI.