SUNCT Syndrome: diagnosis and treatment

Short-lasting Unilateral Neuralgiform headache attacks with Conjunctival injection and Tearing (SUNCT) is a syndrome predominant in males, with a mean age of onset around 50 years. The attacks are strictly unilateral, generally with the pain persistently confined to the ocular/periocular area. Most attacks are moderate to severe in intensity and burning, stabbing or electrical in character. The mean duration of paroxysms is 1 minute, with a usual range of 10 to 120 seconds (total range 5 to 250 seconds). Prominent, ipsilateral conjunctival injection and lacrimation regularly accompany the attacks. Nasal stuffiness/rhinorrhoea are frequently noted. In addition, there is subclinical forehead sweating. During attacks, there is increased intraocular pressure on the symptomatic side and swelling of the eyelids. No changes in pupil diameter have been observed. Attacks can be triggered mostly from trigeminally innervated areas, but also from the extratrigeminal territory. There are also spontaneous attacks. An irregular temporal pattern is the rule, with symptomatic periods alternating with remissions in an unpredictable fashion. During active periods, the frequency of attacks may vary from <1 attack/day to >30 attacks/hour. The attacks predominate during the daytime, nocturnal attacks being seldom reported. A SUNCT-like picture has been described in some patients with either intra-axial or extra-axial posterior fossa lesions, mostly vascular disturbances/ malformations. In the vast majority of patients, however, aetiology and pathogenesis are unknown. In SUNCT syndrome, there is a lack of persistent, convincingly beneficial effect of drugs or anaesthetic blockades that are generally effective in cluster headache, chronic paroxysmal hemicrania, trigeminal neuralgia, idiopathic stabbing headache ('jabs and jolts syndrome'), and other headaches more faintly resembling SUNCT syndrome. Single reports have claimed that carbamazepine, lamotrigine, gabapentin, corticosteroids or surgical procedures may be of help. However, caution is recommended when assessing any therapy in a disorder such as SUNCT syndrome, in which the rather chaotic and unpredictable temporal pattern makes the assessment of any drug/therapeutic effect per se a particularly difficult matter.