Clinical Notes Where SUNCT Contacts TN: A Case Report Fabrizio Rinaldi, MD; Renata Rao, MD; Elisabetta Venturelli, MD; Paolo Liberini, MD; Stefano Gipponi, MD; Elisa Pari, MD; Eluisa Sapia, MD; Alessandro Padovani, MD, PhD Background.—Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) and trigeminal neuralgia (TN) are unilateral painful conditions that can share the same triggering factors, autonomic features and the main location, as well as the cyclically recurrent crises. Both these syndromes are associated with a high percentage of findings of vascular malformation touching the trigeminal nerve, suggesting a pathophysiological relationship. Case.—In this paper, we report a new case with the main purpose to shine a light on the pathophysiology of these conditions. Conclusion.—Many authors described a SUNCT case deriving from TN or vice versa, suggesting that these conditions are strongly related. Every case of transformed TN or SUNCT should therefore be reported to gather and compare further information. Key words: SUNCT, trigeminal neuralgia, neurovascular contact, vascular malformation (Headache 2013;53:1492-1495) Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) rep- resents a brief headache syndrome first described in 1989. 1 It has been grouped in International Headache Society (IHS) Classification 2004 with other short- duration headache syndromes with prominent auto- nomic features under the general term of trigeminal autonomic cephalalgias (TACs). SUNCT syndrome is a painful condition charac- terized by unilateral neuralgiform attacks, located in the orbital-periorbital areas and associated with ipsi- lateral autonomous phenomena. According to the IHS criteria, pain intensity is moderate to severe, lasting from 5 seconds to 250 seconds. The frequency of the pain can range from two crises per day to 10  30 crises per hour and may be associated with cutaneous trigger zones in a trigeminal topography. Trigeminal neuralgia (TN) is another craniofacial syndrome characterized by brief paroxysmal pain, triggered by innocuous stimuli, and associated with a facial tic but not autonomic manifestations, although lacrimation have been reported in TN. Like SUNCT attacks, those of TN are short lasting (1-120 seconds) and may also be triggered by face touching, teeth brushing, chewing, and so on. 2 For this reason, it is clear how SUNCT shares the triggering factors of TN, the autonomic features and the main location (orbital) of the other TACs and the same cyclically recurrent crises of SUNCT and TN. The marked similarities between SUNCT and TN suggest a pathophysiological relationship. From the Clinical Neurology, University Hospital “Spedali Civili,” Brescia, Italy. Address all correspondence to F. Rinaldi, Clinical Neurology, University Hospital “Spedali Civili,” Piazzale Spedali Civili 1, Brescia 25100, Italy. Accepted for publication September 14, 2012. Conflict of Interest: The authors report no conflict of interest. ISSN 0017-8748 doi: 10.1111/head.12007 Published by Wiley Periodicals, Inc. Headache © 2013 American Headache Society 1492