ASL perfusion in acute ischemic stroke: The value of CBF in outcome prediction

The application of novel advanced magnetic resonance imaging (MRI) techniques in clinical practice has significantly improved diagnostic accuracy in early detection of acute ischemic stroke (AIS), additionally allowing outcome prediction. The introduction of arterial spin labeling (ASL) perfusion sequence as a standard in MRI protocols is a significant milestone in neuroradiology. The aim of the present study was to demonstrate the potential of ASL sequence for the detection of absolute (aCBF) and relative (rCBF) cerebral blood flow values for an ischemic area and to examine the correlation of the obtained values with the functional outcome of patients.

The study included 205 patients of both sexes over the age of 18 years, suspected with AIS, who met the inclusion criteria. Brain MRI examination according to the protocol for ischemia with fast three-dimensional pseudocontinuous (3D PCASL) ASL technique was used. Statistical analysis of the collected data was performed with SPSS 15.0.

The appearance of the ROC curve indicated good diagnostic characteristics of aCBF in assessing a favorable stroke outcome, demonstrating a high statistical significance (p < 0.001), and high conclusion validity. The value of the rCBF was significantly higher in patients with a favorable outcome compared with patients with a poor outcome (p  < 0.001). The sum of sensitivity and specificity was the highest using aCBF cut-off value of 19.140 mL/100 g/min, and rCBF cut-off of 49.700 of the contralateral side percentage value.

Our study shows that ASL perfusion sequence allows precise detection of perfusion values and provides a reliable insight into outcome prediction.