Optimal Scanning Protocol of Whole-Brain CT Perfusion in Patients With Acute Ischemic Stroke

Whole-brain computed tomography perfusion (CTP) imaging is a dose-intensive imaging technique. We aimed to investigate optimal scanning protocol of the whole-brain CTP using a 320-detector row CT in reducing radiation dose for acute ischemic stroke (AIS) patients. This study included 54 consecutive AIS patients who underwent whole-brain CTP on a 320-detector row CT scanner. We evaluated the penumbra and ischemic core volumes of CTPfull, CTP3/4, and CTP1/2, created using full, 3/4 and 1/2 scanning data, respectively. Wilcoxon signed-rank test, Spearman correlation coefficient, and Bland-Altman analysis were used for the statistical analysis. In addition, hypothetical treatment decisions based on the DEFUSE-3 criteria were also evaluated to determine whether there were any differences in the treatment decisions when using reduced sampling data (CTP3/4 and CTP1/2) compared with full data to assess its clinical efficacy. The penumbra and ischemic core median volumes on CTPfull, CTP3/4, and CTP1/2 were 111.5 mL [interquartile range (IQR): 52.0-173.0] and 5.5 mL (IQR: 0 to 24.0), 106.5 mL (IQR: 47.0 to 170.0) and 6.5 mL (IQR: 0 to 24.0), 106.5 mL (IQR: 48.0 to 178.0), and 5.5 mL (IQR: 0 to 23.0), respectively. There were no significant differences in penumbra (P>0.05) and ischemic core (P>0.05) volumes between CTPfull, CTP3/4, and CTP1/2. Spearman correlation analysis showed significant correlations between CTPfull and CTP3/4 and CTP1/2 for both penumbra (r=0.989 to 0.998, P<0.001) and ischemic core (r=0.997 to 0.982, P<0.001) volumes. The hypothetical treatment strategies determined using reduced sampling data (CTP3/4, and CTP1/2) were largely consistent compared with those using CTPfull. The use of half-scanning data for the whole-brain CTP image with a 320-detector row CT may help to lower the radiation exposure to AIS patients without significant loss of perfusion information.