Tics in TACs: A Step into an Avalanche? Systematic Literature Review and Conclusions

BackgroundTrigeminal autonomic cephalalgias (TACs) comprise cluster headache, paroxysmal hemicrania, short-lasting unilateral neuralgiform headache attacks, and hemicrania continua. In some cases, trigeminal neuralgia (TN, tic douloureux) or TN-like pain may co-occur with TACs. AimThis article will review the co-occurrence and overlap of TACs and tics in order to contribute to a better understanding of the issue and an improved management of the patients. MethodsFor performing a systematic literature review Pubmed was searched using a total of ten terms. The articles identified were screened for further articles of relevance. SummaryTACs are related to tics in various ways. TN or TN-like paroxysms may co-occur with CH, PH, and HC, labeled as cluster-tic syndrome, PH-tic syndrome, and HC-tic syndrome. Such co-occurrence was not only found in the primary TACs but also in secondary headaches resembling TACs. The initial onset of TAC and tic may be simultaneous or separated by months or years. In acute attacks, tic and TAC may occur concurrently or much more often independently of each other. The term cluster-tic syndrome was also used in patients with a single type of pain in a twilight zone between TACs and TN fulfilling none of the relevant diagnostic criteria. Short-lasting neuralgiform headache attacks overlap with TN in terms of clinical features, imaging findings, and therapy.