RESUMO
Objective To explore the way to evaluate hemodynamics of posterior circulation distal ischemia with PWI. Methods Thirty-two patients with vertebral basilar artery severe stenosis were reviewed and compared with thirty normal persons. Information and data of PWI and MRA were collected and analyzed. Following parameters were observed, index of vascular stenosis, collateral vessels, cerebral blood flow (rCBF), cerebral blood volume (rCBV), and mean transit time (rMTT). Results All the patients had at least one vertebral basilar artery with more than 70% stenosis. There were 17 cases with severe vertebral artery stenosis , 20 cases with severe basal artery stenosis , 8 cases with severe superior cerebellar artery stenosis , 17 cases with posterior cerebral artery stenosis , 22 cases with after the traffic artery open , 11 cases with soft meningeal arteries show and 12 cases with small artery show. The ratio of ROI with frontal white matter was lower than the rCBF and rCBV in the country group. MTT value was extended and P value of the parameters in both groups was less than 0.05, reflecting the statistical difference. Conclusions PWI combined with MRA can effectively evaluate the posterior circulation distal ischemia area and tissue perfusion , as well as the hemodynamic status of ischemia area.