SWI/DWI融合图像对急性缺血性脑卒中患者缺血半暗带的评估价值

目的：探讨磁敏感加权成像(SWI)/扩散加权成像(DWI)融合图像对急性缺血性脑卒中(AIS)患者缺血半暗带(IP)的评估价值。方法回顾性分析47例临床和影像均证实的 AIS 患者,由2位医师分别对 SWI/DWI 融合图像进行判读；当融合图像上扩散受限区周围静脉较对侧增多、增粗即定义为磁敏感-扩散加权不匹配(SDM),并以灌注-扩散加权不匹配(PDM)作为“金标准”进行对照,受试者工作特征曲线(ROC)评估融合图像对 IP 的诊断效能,并比较2位医师采用融合图像评估 IP 的一致性。结果2位医师采用融合图像诊断 IP 的曲线下面积(AUC)分别为0.885、0.877,诊断敏感性分别为84.2%、78.9%,特异性分别为92.9%、96.4%；SDM 和 PDM 诊断 IP 的一致性较高,两者无显著差异(P >0.05),且2位医师之间的一致性亦较高(Kappa=0.908,P >0.05)。结论SWI/DWI 融合图像对 AIS 患者的 IP 具有较高的诊断价值,可作为 AIS 患者 IP 评估的一种简单易行的影像学方法。

The diagnostic value of ischemic penumbra with fusion images of SWI and DWI in patients with acute ischemic stroke

Objective To evaluate the diagnostic ability of fusion images of SWI and DWI in ischemic penumbra(IP)of patients with acute ischemic stroke(AIS).Methods 47 AIS patients were retrospective analyzed.Two neuroradiologists analyzed the fusion images of SWI and DWI respectively.SDM was defined as that the hypo-intensity signals of intramedullary or sulcal veins were dilated or increased on fusion images compared with contralateral areas.The results compared with the PDM,which was considered as the“gold standard”.Areas under the receiver operating characteristic curve(AUC)were used to assess the efficacy of SDM which determined by fusion images and compared to PDM.Chi-square test was used to analyze the consistency between the two neuroradiologists and also the consistency between SDM and PDM in IP assessment Results The fusion images of SWI and DWI had a high diagnostic efficacy compared to PDM, AUC of the two radiologists were 0.885,0.877,the diagnostic sensitivity were 84.2%,78.9% and specificity were 92.9%,96.4%respectively.There was also a high consistency in SDM assessment through fusion images between the two neuroradiologists (Kappa=0.908,P >0.05). Conclusion Fusion images of SWI and DWI have a high diagnostic efficacy in IP assessment,which may be considered as a simple approach for IP assessment in patients with AIS.