磁敏感加权成像突出血管征在卒中患者中的应用价值

Application value of prominent vessel sign on magnetic susceptibility weighted imaging in stroke

急性卒中患者低灌注区域内脑组织局部血管内氧摄取率增高,导致毛细血管及静脉内脱氧血红蛋白与含氧血红蛋白比值增高。利用磁敏感加权成像对脱氧血红蛋白等顺磁性物质的敏感性,脱氧血红蛋白浓度高的血管在SWI上呈现为突出血管征(prominent vessel sign,PVS)。PVS的出现可用于评估缺血半暗带及脑灌注疗效,也预示了侧支循环建立及脑储备能力,PVS的存在也与卒中预后有一定关系。

In the patients with acute stroke,the oxygen extraction fraction（OEF）is increased in the hypoperfused parenchyma,resulting in an increase in the ratio of deoxygenated hemoglobin to oxygenated hemoglobin in the capillary and vein.Because Susceptibility weighted imaging（SWI）is exquisitely sensitive to paramagnetic substances,such as deoxyhemoglobin,prominent vessel sign（PVS）will appear on SWI when the concentration of deoxyhemoglobin in the veins increases.The presence of PVS can be used to assess ischemic penumbra and cerebral reperfusion therapy,and also predict the establishment of collateral circulation and brain reserve capacity.Moreover,the presence of PVS is also related to the prognosis of stroke.