Definition

Short lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) is a trigeminal autonomic cephalgia (TAC) characterized by attacks of trigeminal pain accompanied by red eye (conjunctival injection) and tearing (lacrimation.) The syndrome is predominant in males, with a mean age of onset around 50 years.1 The attacks are strictly unilateral, generally with the pain persistently confined to the ocular/periocular area.2 Generally, the pain is severe and neuralgic in character.1

An irregular temporal pattern is the rule, with symptomatic periods alternating with remissions in an unpredictable fashion.2 The attack frequency varies from less than one attack daily to more than 60 attacks per hour. The attacks predominate during the daytime, nocturnal attacks being seldom reported.1

Another TAC, short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA) should also be considered at the diagnostic stage. Like SUNCT, SUNA is a trigeminal autonomic cephalgia (TAC) characterized by attacks of trigeminal pain accompanied by cranial autonomic symptoms other than red eye and tearing.

SUNCT Diagnostic criteria:
A At least 20 attacks fulfilling criteria B–E
B Attacks of unilateral, orbital, supraorbital or temporal stabbing or pulsating pain last 5–240 seconds
C Pain is accompanied by ipsilateral conjunctival injection and lacrimation
D Attacks occur with a frequency from three to 200 per day
E Not attributed to another disorder

Table: J Neurol Neurosurg Psychiatry 2005;76:301-305 doi:10.1136/jnnp.2004.036012 http://dx.doi.org/10.1136/bmj.e2407

1. Matharu MS1, Cohen AS, Boes CJ, Goadsby PJ. Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing syndrome: a review.Curr Pain Headache Rep. 2003 Aug;7(4):308-18.↩
2. Pareja JA1, Caminero AB, Sjaastad O. SUNCT Syndrome: diagnosis and treatment. CNS Drugs 2002;16(6):373-83.↩

further reading:
P J Goadsby. Trigeminal autonomic cephalalgias: fancy term or constructive change to the IHS classification? J Neurol Neurosurg Psychiatry 2005;76:301-305 doi:10.1136/jnnp.2004.036012
T. Sprenger, MD, H. Boecker, MD, T. R. Tolle, MD PhD, G. Bussone, MD, A. May, MD and M. Leone, MD, Specific hypothalamic activation during a spontaneous cluster headache attack. Neurology February 10, 2004 vol. 62 no. 3 516-517.
Benoliel, Rafael. Trigeminal Autonomic Cephalgias. British Journal of Pain 6.3 (2012): 106–123.
Michele Viana, Cristina Tassorelli, Marta Allena, Giuseppe Nappi, Ottar Sjaastad, Fabio Antonaci. Diagnostic and Therapeutic Errors in Trigeminal Autonomic Cephalalgias and Hemicrania Continua: a Systematic Review The Journal of Headache and Pain, 14.1 (2013): Page 1
Leonne, M. Bussone, G. Pathophysiology of Trigeminal Autonomic Cephalalgias Lancet Neurology 8.8 (2009): 755-64
Rev. 07/17