双能量CT在AIS血管内治疗术后即刻颅内出血诊断中的应用价值

Application of dual-energy CT immediately in the diagnosis of intracranial hemorrhage after endovascular treatment of acute ischemic stroke

目的探讨双能量CT(DECT)在急性缺血性卒中(AIS)血管内治疗术后即刻鉴别脑出血及对比剂外渗中的临床应用价值。方法连续收集50名AIS并接受血管内治疗的患者,于术后立即行DECT扫描,经后处理获得混合能量图(MIX)、虚拟平扫图(VNC)、碘覆盖图(IOM)及虚拟去钙图(VNCa),经综合分析诊断,以术后24~48 h随访CT平扫或磁共振SWAN序列为标准进行对照,计算DECT诊断出血的敏感度、特异度、阳性预测值、阴性预测值、准确率。结果50例患者中41例患者MIX图上见高密度影。DECT后处理分析诊断对比剂外渗29例,后经随访证实24例为对比剂外渗,余5例继发出血转化;DECT诊断出血合并对比剂外渗12例,后经随访全部证实;DECT诊断10处不典型钙化,后经随访或结合前片对照全部证实。DECT识别AIS血管内治疗术后即刻颅内出血敏感度为70.6%(12/17)、特异度为100%(36/36)、阳性预测率为100%(12/12)、阴性预测率为87.8%(36/41)、准确率为90.6%(48/53)。结论急性缺血性卒中血管内治疗术后可以即刻运用双能量CT对颅内早期出血准确诊断。

Objective To explore the clinical value of DECT in differentiating between intracranial hemorrhage and contrast medium extravasation immediately after endovascular treatment of acute ischemic stroke(AIS).Methods 50 patients with acute ischemic stroke who underwent endovascular treatment and follow-up DECT immediately were included.Mixed energy images(MIX),virtual non-contrast images(VNC),iodine overlay maps(IOM)and virtual non-calcium images(VNCa)were obtained and evaluated after post-processing.Taking the conventional CT or MR susceptibility weighted angiography(SWAN)images within 24~48 h after operation as the reference standard,the sensitivity,specificity,positive and negative predictive value,accuracy of dual energy CT in the diagnosis of hemorrhage were calculated.Results Among the 50 patients,41 patients had high density on MIX.29 cases were diagnosed as contrast medium extravasation by DECT,24 of them were confirmed by follow-up scan,the other 5 cases were identified as hemorrhagic transformation.12 cases were diagnosed as intracranial hemorrhage complicated with contrast medium extravasation by DECT,all were confirmed by follow-up scan.10 were diagnosed as atypical calcification by DECT,all were confirmed by follow-up or former scan.The sensitivity,specificity,positive and negative predictive value,accuracy of DECT in the diagnosis of hemorrhage after endovascular treatment of AIS were 70.6%(12/17),100%(36/36),100%(12/12),87.8%(36/41)and 90.6%(48/53),respectively.Conclusions DECT can be used to accurately diagnose intracranial hemorrhage immediately after endovascular treatment of AIS.