Ejaculation-Triggered Reversible Cerebral Vasoconstriction Syndrome: A Case Report with Longitudinal Neuroimaging.

A 40-year-old man presented with thunderclap headache (TCH) and vomiting post-masturbatory ejaculation. He reported a similar episode with posterior neck pain five days earlier after ejaculation. Unlike his migraine history, these headaches were unusually severe. Upon arrival, physical and neurological examinations were unremarkable except for an elevated blood pressure (154/110 mmHg). Brain MRI/MRA systematically ruled out intracerebral/subarachnoid hemorrhages, aneurysms, cerebral venous thrombosis, and cervical artery dissection, with preserved flow voids on B-PASS, T2, and T2-FLAIR. Notably, MRA demonstrated multiple segmental vasoconstrictions compared to a baseline MRA from five years prior. With an RCVS2 score of 8, he was diagnosed with reversible cerebral vasoconstriction syndrome (RCVS). Symptoms resolved within 10 days of starting oral verapamil (120 mg/day), and follow-up MRA at one month showed partial improvement. This case highlights RCVS manifesting as a secondary cause sharing features with the proposed headaches associated with sexual activity (HSA) spectrum. RCVS is the predominant secondary cause of HSA (67-90%), often indistinguishable from primary HSA at onset due to the shared presentation of sudden TCH. Its pathophysiology likely involves an orgasm-induced sympathetic surge causing transient dysregulation of cerebral vascular tone. This case emphasizes that thorough neurovascular imaging is important in HSA to differentiate RCVS from primary headaches, ensuring the prompt initiation of calcium channel blockers and the avoidance of triptans.