Fax +41 61 306 12 34 E-Mail karger@karger.ch www.karger.com Original Paper Cerebrovasc Dis 2012;34:376–384 DOI: 10.1159/000343658 Hyperintensity of Distal Vessels on FLAIR Is Associated with Slow Progression of the Infarction in Acute Ischemic Stroke N. Pérez de la Ossa a M. Hernández-Pérez a S. Domènech b P. Cuadras c A. Massuet b M. Millán a M. Gomis a E. López-Cancio a L. Dorado a A. Dávalos a a Stroke Unit, Department of Neurosciences, b Department of Magnetic Resonance Imaging, Institut de Diagnòstic per la Imatge (IDI), and c Department of Radiology, Hospital Universitari Germans Trias i Pujol, Badalona, Spain FLAIR sequence was graded as absent, subtle or prominent by two readers. Results: A total of 70 patients were included in the study. Mean time between baseline CT and MRI was 124 8 82 min. ASPECTS score on baseline CT was 10 in 34% of patients, 9 in 49% and 8 or less in 17%. ASPECTS score was 2 (1–3) points lower in the DWI and this decrease did not cor- relate with the time elapsed between the two exams. Dis- tal HV sign was observed in 57/70 (81%) patients (subtle in 33 and prominent in 24). HV was more frequently observed in patients with proximal artery occlusion. There were no differences regarding stroke severity, stroke subtype and ASPECTS score on baseline CT between groups. Patients with prominent HV showed a lower progression of the isch- emic area [median ASPECTS score decrease, 1 (1–0)] com- pared with patients with subtle HV [median ASPECTS score decrease, 2 (2–1)] and patients with absence of HV [median ASPECTS score decrease, 3 (4–3)] (p ! 0.001). Prominent HV was independently associated with slow progression of isch- emia in a multivariate logistic regression analysis adjusted by systolic blood pressure on admission, site of occlusion and time elapsed between both neuroimaging exams compared to the absence of HV (OR, 16.2; 95% CI, 2.1–123.1) and to sub- tle HV sign (OR, 6.1; 95% CI, 1.5–23.9). Conclusion: HV sign on FLAIR, especially if prominent, is associated with a slow pro- gression of the ischemic area in acute stroke patients with Key Words Acute stroke  Hyperintense vessels  Fluid-attenuated inversion recovery  Magnetic resonance imaging  Ischemia progression Abstract Background: Hyperintensity of distal vessels on FLAIR-MRI has been associated with a higher grade of arterial collaterals and a smaller infarct volume in acute stroke patients. No studies analyze the influence of the hyperintense vessel (HV) sign on the speed of the ischemia progression during the first hours. Our aim was to study the association of the HV sign with progression of infarction in acute stroke patients. Methods: From a prospectively derived stroke database, we retrospectively selected acute stroke patients with a large artery occlusion of the anterior circulation admitted to our comprehensive stroke center with available baseline CT scan and a multimodal MRI carried out thereafter to make a deci- sion about endovascular treatment. Progression of the isch- emic area was calculated as the difference in the Alberta Stroke Program Early CT Scan (ASPECTS) score between CT scan and diffusion-weighted imaging (DWI). Slow progres- sion was considered as no change or 1 point decrease on the ASPECTS score between both exams. The presence of HV on Received: April 8, 2012 Accepted: September 20, 2012 Published online: November 29, 2012 Dr. Natalia Pérez de la Ossa Herrero Stroke Unit, Department of Neurosciences Hospital Universitari Germans Trias i Pujol, Carretera del Canyet s/n ES–08916 Badalona (Spain) E-Mail natperezossa  @  gmail.com © 2012 S. Karger AG, Basel 1015–9770/12/0346–0376$38.00/0 Accessible online at: www.karger.com/ced