Background: Symptomatic cluster headache (CH) secondary to internal carotid artery dissection (ICAD) has been frequently reported, however, as far as we know, the coexistence of episodic CH and acute symptomatic CH secondary to ICAD has not.
Case report: A 39 year-old man, affected by episodic CH since the age of 19, presented an atypical headache associated with his usual autonomic symptoms. After a series of negative tests, MRA eventually revealed dissection of the right distal internal carotid artery.
Discussion and conclusions: The coexistence of episodic CH and acute CH symptomatic of ICAD in our patient suggests that, at least in some cases, CH and ICAD may be different expressions of a common underlying cause: hidden vessel wall damage. When risk factors and the change - though partial - of clinical features suggest symptomatic cases, CH patients have to be strictly monitored over time. Given the lack of a gold standard investigation for dynamic diseases such as dissections, these patients require multimodal diagnostic investigation over time, even in cases where exams are normal at onset.