Objective To evaluate the application of Dual source CT cerebral perfusion imaging (CTP)and CT angiography(CTA) in patients with hyperacute stroke.Methods Convention cerebral plain CT, CTP and CTA were performed in 89 patients with hyperacute ischemic stroke within 6 hours of onset of symptom.All cases were reexamined by cerebral plain CT after 2 to 21 days.Dynamic CTP images were processed with the "CT perfusion"software on workstation.Quantitative analysis of cerebral perfusion parameters were performed on CTP images.CT angiography was reconstructed to show carotid and intracerebral artery.Results Conventional plain CT of the 36 cases found no abnormality in 73 cases and early infarction signs in 16 cases,However, abnormal perfusion changes corresponding to clinical symptoms were found in 89 cases,including decrease in cerebral blood flow(CBF) and cerebral blood volume(CBV),delayed time to peak(TTP).There were significant differences of CBF, CBV and TTP between infarction side and contralateral side(P<0.01).CTA demonstrated stenosis or occlusion of middle cerebral artery and internal carotid artery in 89 cases.Cunclusion CTP can early show the ischemic extent and ischemic penumbra , CTA can show the stenosis or occlusion artery in patients with hyperacute stroke.