Abstract: Objective To study the clinical diagnosis value of the combination application of CT perfusion(CTP) and CT angiography (CTA) in cerebrovascular diseases. Methods 20 patients suspected of cerebrovascular diseases（CVD） were examined with CTP and CTA. All the CTA data were send to 3D post processing card for MIP, SSD and VR reconstruction. Perfusion data were analyzed by CT perfusion package. The absolute TTP, MTT, CBV, CBF values and the relative value between normal and pathological sides were calculated.Results Low perfusion which indicated the prophase of ischemia infarction were detected in 15 cases, 12 cases were located in MCA area, and 10 of them the stenosis of responsible arteries were demonstrated. The degree of the vessel stenosis can be evaluated exactly by CTA source images. Other 5 cases were located in the area of PCA and no positive detection in CTA examination.Conclusion Combined application of CTP and CTA can finish two examinations at the same time in the fast and economic way. Both the hemodynamics changing and the morphology of the vessels were demonstrated which providing omnidirectional pathophysiological information for clinical diagnosis and therapy.

Key words: CT perfusion, CT angiography, cerebrovascular diseases