Application Of CT Perfusion Imaging And CT Angiography In Dignosis Of Ischemia Cerebrovascular Disease

Objective:The purpose of this study is to assessment the value of combining computerizedtomography perfusion imaging (CTP) with computerized tomography angiography (CTA)in the applications of diagnosis in ischemia cerebrovascular disease, and to discuss therelationships between cerebral hemodynamics and the blood-supply artery vascularstenosis and clinical symptoms.Methods:There are48patients whose clinical symptoms displayed dizziness, barylalia,myasthenia, hypalgesia, hemiplegia, unconsciousness, distortion of commissure. Thosewho suspiciously suffered ischemia cerebrovascular disease underwent conventional CT toexclude intracranial hemorrhage, brain tumor, and then CTP examination was performed,and CTA examination was performed five minutes later. After the post-prossessing, theperfusion parameters were got. The datas consist of cerebral blood volume (CBV), cerebrablood flow (CBF), mean transit time (MTT), time to peak (TTP). CTA datas weretransmitted to the workstation, and multiple planar reformation (MPR), maximum intensityprojection (MIP), curved planar reformation (CPR), volume rendering (VR) were obtained.Stenosis degree of feeding arteries were recorded. All statisticses were performed usingSPSS13.0software. Variables are presented as means±standard deviation. Testing theischemic central area and ischemic surrounding area by t test. Using spearman rankcorrelation to analyze the correlation between the stenosis degree of feeding artery andperfusion parameters. P<0.05suggest that the results are significance.Results: 1. After CTP examination, patients who suspiciously suffered ischemia cerebrovascular disease could get more information than conventional CT examination.2. The parameters of CBF, MTT, TTP were significantly different between theaffected side and the contralateral side (P＜0.05). CBV was no significantly different (P＞0.05). CBF was decreased in abnormal area. MTT, TTP parameters were prolonged.3. In conventional CT,15patients showed cerebral infarction, the parameters of CBF,MTT, MTT, TTP were significantly different between ischemic central area and ischemicsurrounding area. CBF, CBV parameters in ischemic central area is less than ischemicsurrounding area. MTT and TTP parameters were prolonged obviously.4.25cases have artery stenosis or occlusion, parts of them have cerebral infarction.There is no correlation between degree of artery stenosis and clinical symptoms. Ifcollateral circulations were reconstructed, even artery had occluded, no infarction wouldocuur. MTT, TTP showed abnormal in CTP examination.5. There was statistically correlation between the values of TTP and MTT and thedegree of artery Stenosis, MTT (r=0.499, P＜0.05), TTP (r=0.673, P＜0.05), While theCBV, CBF had no significant correlation.Conclusion:1. The CTP examination clearly demonstrates the abnormal hemodynamic changes ofbrain. There is no significant correlation between the values of CBV, CBF and the degree ofartery stenosis, therefore the brain tissue Ischemia situation cannot be completely predictedby degree of artery stenosis and clinical symptoms.2. Combining with CTA and CTP to evaluate the function and morphology of thebrain in the patients who suffering from ischemic cerebrovascular disease. These examinations play an important role in diagnosis and treatment of ischemia cerebrovasculardisease.