Hypointense Vessels Detected by Susceptibility‐Weighted Imaging Identifies Tissue at Risk of Infarction in Anterior Circulation Stroke

ABSTRACT BACKGROUND AND PURPOSE The diagnostic value of susceptibility‐weighted magnetic resonance imaging of acute stroke patients has shown potential as a surrogate marker of impaired hemodynamics. We investigate the value of asymmetrical hypointense cerebral vessels (HV) for the identification of vessel status and tissue at risk of infarction (TaR). METHODS Symmetry of HV was visually rated on SWI data from a well‐defined population of acute anterior circulation stroke with onset 6 seconds. Status of the extra‐ and intracranial arteries was assessed by ultrasound and MR angiography. RESULTS 35 patients were included (12 women; median age 69 years, IQR 61–77; median NIHSS at admission 10, IQR 6–20). Asymmetrically distributed HV were detected at the stroke hemisphere in 25 patients (71%). Of those, 12 patients displayed occlusion of the middle cerebral artery, whereas occlusion of the extracranial ICA was detected in 6 patients. TaR was larger, yet not significantly different in patients with asymmetrically HV (mean volume 38.9 ml, SD 52.9 ml) compared to patients showing symmetrical HV (4.2 ml; SD 10.7 ml, p‐value 0.081). Significant differences where, however, found after excluding patients with extracranial ICA occlusions (42.9 ml; SD 50.4 ml vs. 4.2 ml, SD 10.8 ml, p‐value 0.025). CONCLUSION Visual analysis of HV in SWI identifies tissue at risk in patients with anterior circulation stroke. Potentially pre‐existing extracranial ICA occlusions leading to prominent HV have to be considered as a confounding factor.