【摘要】 目的 探讨磁共振弥散（DWI）和灌注成像（PWI）结合,对短暂性脑缺血（TIA）分类及预后评估的价值。方法 41例TIA患者入选,第1次DWI及PWI均在发病后24 h内进行,DWI阳性或PWI异常者分别于7～11 d内、1～3月复查T₂WI、FLAIR、DWI及PWI;DWI阴性及PWI正常者7～14d后复查,如无异常,则随访终止,反之,同上随访。症状侧脑血容量（CBV）和平均通过时间（MTT）值分别除以对侧对照正常半球的CBV和MTT值得到其相对值,即rCBV和rMTT,rCBF值由rCBV除以rMTT得到。根据随访后的DWI表现,TIA患者被分为预后好与差2组。结果 28例（68%）患者有DWI或PWI的异常。在这些患者中15例仅有DWI异常,6例仅有PWI异常,7例既有DWI异常又有PWI异常。预后差的TIA患者rCBF和rCBV均明显高于预后好的患者。结论 磁共振弥散和灌注结合有助于评价TIA患者缺血的程度,对于治疗及预后判断都非常有价值。更多还原

【Abstract】 Objective To investigate the classification and the evaluation of prognosis of transient ischemic attack(TIA) by MR diffusion-weighted imaging(DWI) in combination with perfusion-weighted imaging(PWI).Methods 41 patients with a admitted diagnosis of TIA underwent DWI and PWI studies within 24 hours,within 7-14 days and 1-3 months ofter onset.The values of cerebral blood volume(CBV) and mean transit time(MTT) were measured in the abnormal regions and the normal contralateral regions in white matter at each time point.The ratio of abnormal regions to control regions of interest were calculated.The data were expressed as relative CBV and MTT.Relative CBF was get by rCBV/rMTT.TIA patients were divided into two groups:poor and good prognosis according to the DWI results after follow-up.Results MR imaging showed abnormal changes of brain in 28 patients(68%),including 15 cases on DWI,7 on both DWI and PWI and 6 cases only on PWI.In comparison with the cases with good prognosis,the rCBF and rCBV were significantly higher in poor prognosis patients.Conclusion DWI and PWI can be used for classifications of TIA,which will contributes a lot to assess the ischemic degree for treatment and prognosis of TIA patients.更多还原