Clinical Spectrum of Reversible Cerebral Vasoconstriction Syndrome With and Without Angiographic Vasoconstriction: A Retrospective Study of 84 Hospitalized Patients.

OBJECTIVE: To determine whether patients with reversible cerebral vasoconstriction syndrome (RCVS) without demonstrable vasoconstriction differ clinically from those with angiographically confirmed vasoconstriction. METHODS: We retrospectively studied consecutive patients with RCVS hospitalized at a tertiary headache center in Japan between February 2011 and March 2026. Patients were classified according to the presence or absence of angiographically demonstrable vasoconstriction on magnetic resonance angiography. Demographic characteristics, clinical features, surrogate markers of disease severity, treatment patterns, triggering factors, neuroimaging abnormalities, and outcomes were compared between groups. RESULTS: Eighty-four patients were included: 61 with demonstrable vasoconstriction and 23 without. The two groups did not differ significantly in age (median, 51 vs. 53 years; p = 0.213), female predominance (80% vs. 78%; p = 1.000), or migraine history (59% vs. 57%; p = 1.000). Clinical features were similar, including the number of thunderclap headache episodes (median, 4 vs. 4; p = 0.577) and the interval from the first to the last thunderclap headache (median, 6 vs. 6 days; p = 0.460). Time to hospitalization, length of hospital stay, calcium channel blocker use (98% vs. 100%; p = 1.000), neuroimaging abnormalities (8% vs. 9%; p = 1.000), and persistent neurological sequelae (2% vs. 0%; p = 1.000) were also comparable. CONCLUSION: Patients without demonstrable vasoconstriction exhibited clinical characteristics, severity indicators, management, and outcomes similar to those with confirmed vasoconstriction. These findings suggest that the two groups may share a common clinical spectrum; however, confirmation in larger prospective studies is warranted.