Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) with preserved refractory period: report of three cases

A 62-year gentleman complained of recurrent brief (20–30 s) episodes of right periorbital pain for last 2 years. Starting with 1–5 episodes/day, his pain attacks increased to 20–50 attacks/day for last 2 months. In between attacks, he remained asymptomatic. Pain was severe, non-throbbing, stabbing and most episodes were accompanied by lacrimation and redness of right eye. Pain produced visible distress but without motor restlessness (supplementary video). There was no photophobia, phonophobia, vomiting or exacerbation of pain with head movement. Pain could be triggered by touching right periorbital area and mouth opening. Patient reported absent refractory period. There was no family history of migraine. NSAIDS did not relieve his pain. Examination of the patient was unremarkable. A triggered attack with conjunctival congestion and lacrimation was witnessed (supplementary video). Refractory period of variable duration (1–10 min) was observed at different occasions. MRI of the head revealed vascular loop around right trigeminal nerve (Fig. 1a). A trial of indomethacin and oxygen inhalation failed to produce any response. Oxcarbazepine (900 mg/day) reduced the frequency of headache attacks. Oxcarbazepine induced sedation and ataxia precluded further increase in its dose. Lamotrigine was added (200 mg/day). It produced remission for last 6 months.

A 56-year gentleman complained of intermittent, brief (10–90 s) attacks of severe right supra-orbital lancinating pain attacks for 1 year. Episodes of attacks increased to 25–30/day from 1 week from initial 1–6/day. Inter-attack period was asymptomatic. Lacrimation, mild redness of right eye and rhinorrhoea (with longer attacks) accompanied most attacks. Pain could be triggered by touching right forehead, spitting and chewing. There was no photophobia, phonophobia, vomiting, associated motor restlessness or pain exacerbation with head movement. There was no history of refractory period. There was no family history of migraine. Carbamazepine, topiramate, amitriptyline, gabapentin and pregabalin received in last 1 year did not work. Neurological examination was normal. A triggered attack conforming to history was witnessed. An intervening refractory period of 10 min or more was observed in most witnessed episodes. MRI of the head showed superior cerebellar artery loop around right trigeminal nerve (Fig. 1b). A trial of indomethacin and oxygen inhalation did not relieve his pain. With lamotrigine (200 mg/day) he achieved remission for last 1 year.

A 64-year gentleman presented with recurrent, brief (10–30 s) attacks of severe, stabbing pain involving right periorbital area for 6 months. For 1 month, his attacks increased to 5–30/day from initial 1–2/day. Most episodes were accompanied by lacrimation, redness and partial drooping of right eye lid (with longer attacks). There was no photophobia, phonophobia, vomiting or restlessness. Touching right eyelid and teeth brushing could trigger attack. Patient was not sure about the refractory period. There was no family history of migraine. At the time of consultation, he was taking carbamazepine (600 mg/day) for a week with resultant 2–3 attacks/day. His clinical examination was normal. One spontaneous attack (25 s long) with conjunctival congestion and lacrimation was witnessed. Repeated attempts to trigger the headache failed; however, few spontaneous attacks were witnessed upon drug discontinuation. His MRI of the head showed superior cerebellar artery loop around both trigeminal nerves (Fig. 1c). He was restarted on carbamazepine (400 mg/day) which promptly abolished his spontaneous attacks.