A 48-year-old man complained of episodic bursts of sharp, shooting left-sided facial pain.

Our patient had multiple episodes of severe, brief (few seconds), stabbing, unilateral (left-sided only) facial pain, affecting predominantly the dermatomal zones innervated by the maxillary (V2) and mandibular (V3) branches of the trigeminal nerve (CN V), and to a lesser extent the dermatomal zone innervated by the ophthalmic (V1) branch. The episodes of pain were frequently triggered by painless sensory stimuli such as a draft of cold wind, chewing, or even a kiss. The episodes were repetitive, usually three to four in a given day. Between attacks, he had no symptoms. Neurologic examination was normal.

Our patient provided an accurate description of a paroxysmal unilateral painful condition, with periods of remission, affecting the trigeminal nerve and typical of trigeminal neuralgia. The nucleus of the trigeminal nerve stretches from the midbrain (mesencephalic nucleus) through the pons (principal sensory and motor nucleus of V) to the upper cervical spinal cord region (nucleus of the spinal tract of the trigeminal nerve), where it becomes continuous with Lissauer tract. The nucleus of the spinal tract of the trigeminal nerve is divided into a pars oralis, a pars interpolaris, and a pars caudalis.