Keywords:
CT, Neuroradiology brain, CT-Quantitative, Computer Applications-Detection, diagnosis, Ischaemia / Infarction, Retrospective, Not applicable, Performed at one institution
Authors:
S. Ichikawa, H. YAMAMOTO; Kurashiki/JP
DOI:
10.26044/ecr2020/C-07900
Results
Noise levels (SD) of CT perfusion data at each dose level were as follows: 75 mAs, 11.2±1.1; 60 mAs, 12.5±1.2; 45 mAs, 14.4±1.4; 30 mAs, 17.7±1.7; and 15 mAs, 25.0±2.4.
The quantitative values of each CT perfusion parameter at different dose levels in the affected and contralateral normal regions are summarized in Table 1 . All quantitative values of the low-dose CT perfusion data sets at the tube current-time product of 60 and 45 mAs were comparable with those of the original CT perfusion data (p>0.05 for all). At the tube current-time product of 30 mAs, CBF, MTT, and TTP of the affected region showed significant differences (p<0.05), while no significant differences were shown in CBV of the affected region and all parameters of the contralateral normal region (p>0.05). We found significant differences in CBV and TTP of the affected region and in MTT and TTP of the contralateral normal region at the tube current-time product of 15 mAs (p<0.05). Representative CT perfusion images at different dose levels are shown in Fig. 3 and Fig. 4 .