Background: Fluid-attenuated inversion recovery (FLAIR) sequences may reveal hyperintense vessel signals (HVS) at the acute stage of cerebral ischemia. The aim of this study was to test the hypothesis that HVS are associated with a worse outcome. Methods: We included 30 consecutive patients admitted within 12 h after onset of hemispheric cerebral ischemia. The outcome was assessed with the modified Rankin Scale at month 1. Results: Proximal HVS were present in 9 patients and distal HVS in 16. All patients with proximal occlusions on time-of-flight sequences had distal HVS on FLAIR. Patients with poor outcome at month 1 (modified Rankin Scale 3–6) more frequently had had HVS on MRI (12/13 vs. 4/17; p< 0.001). Conclusion: Distal HVS found on FLAIR sequences within 12 h of acute cerebral ischemia are associated with a worse 1-month outcome.