Unilateral trigeminal motor nerve neuropathy.

Pure trigeminal motor neuropathy is represented by trigeminal motor weakness without signs of trigeminal sensory or other cranial nerve involvement. We present a case of 45-year-old male complaining of difficulty in chewing with facial asymmetry on right side. He had no sensory disturbances. History, neurological examination, CT and MRI led to the diagnosis of unilateral trigeminal motor nerve neuropathy. The cause may have been an autoimmune reaction to the viral infection.