3-T high-resolution PDW imaging is a reproducible tool for measuring BA dimensions. In patients with advanced BA atherosclerosis, PR lesions are more frequently observed and contain larger plaques than non-PR lesions.

The purpose of this study was to investigate the relationship between hyperperfusion and hemorrhagic transformation (HT) in acute ischemic stroke (AIS). Pseudo-continuous arterial spin labeling (ASL) with background suppressed 3D GRASE was performed during routine clinical magnetic resonance imaging (MRI) on AIS patients at various time points. Arterial spin labeling cerebral blood flow (CBF) maps were visually inspected for the presence of hyperperfusion. Hemorrhagic transformation was followed during hospitalization and was graded on gradient recalled echo (GRE) scans into hemorrhagic infarction (HI) and parenchymal hematoma (PH). A total of 361 ASL scans were collected from 221 consecutive patients with middle cerebral artery stroke from May 2010 to September 2013. Hyperperfusion was more frequently detected posttreatment (odds ratio (OR) = 4.8, 95% confidence interval (CI) 2.5 to 8.9, P < 0.001) and with high National Institutes of Health Stroke Scale (NIHSS) scores at admission (P<0.001). There was a significant association between having hyperperfusion at any time point and HT (OR = 3.5, 95% CI 2.0 to 6.3, P < 0.001). There was a positive relationship between the grade of HT and time-hyperperfusion with the Spearman's rank correlation of 0.44 (P = 0.003). Arterial spin labeling hyperperfusion may provide an imaging marker of HT, which may guide the management of AIS patients post tissue-type plasminogen activator (tPA) and/or endovascular treatments. Late hyperperfusion should be given more attention to prevent high-grade HT.

BACKGROUND AND PURPOSE:There are limited studies on the morphologic characteristics of MCA atherosclerotic stenosis. Our aim was to quantitatively assess the remodeling pattern and plaque distribution of atherosclerotic MCAs with 3T high-resolution MR imaging.

3T high-resolution MRI combined with DSA offered clear visualization of vessel wall features and accurate assessment of the vessel lumen in IDAs. This combined approach would be highly useful for understanding the underlying pathological status of IDAs and in guiding treatment choices.