Abstract：Objective: To study the hemodynamic patterns demonstrated in whole brain CT perfusion images(CTPI) in patients with symptomatic severe stenosis or occlusion of intracranial internal carotid artery(ICA). Materials and Methods: The CTPI data of 23 patients with symptomatic severe stenosis(>70%) or occlusion of ICA were analyzed retrospectively. The 4 dimensional CT angiography(4D-CTA) and the parameter maps of CTPI including cerebral blood volume(CBV), cerebral blood flow(CBF), mean transit time(MTT), time to peak(TTP) and delay maps were generated in the off-line workstation by using specific software. The stenosis degree of ICA, clinical symptoms, location of infarction and features of CTPI and the values of parameter maps were recorded. Paired t-test was used to compare the values of ipsilateral with contralateral normal areas in CTP maps. Results: Fifteen patients had occlusion and 8 patients had severe stenosis of ICA. Thirteen cases had infarction in middle cerebral artery(MCA) or anterior cerebral artery(ACA) areas, 6 cases had watershed infarction, 2 cases had lacunar infarction and 2 cases had no infarction. The patterns of CTPI abnormalities included the following: ①Normal or slightly increased CBV/CBF and increased MTT/TTP/Delay time(4 csaes). ②Normal CBV, slightly decreased in CBF and decreased in MTT/TTP/Delay time(3 cases). ③Decreased obviously in CBV/CBF, decreased in regional MTT associated with prolong MTT/TTP/Delay time(16 cases). CBV, CBF, TTP and Delay values of ipsilateral side brain areas had significant difference when compared with those of contralateral brain areas(P<0.05). Conclusions: 320-row CT is a reliable technique in showing intracranial ICA stenosis and perfusion abnormalities.
2012, Vol. 23 
