薄层CT平扫对主动脉夹层诊断的价值

目的 探讨薄层CT平扫对主动脉夹层的临床诊断价值。方法 回顾性分析56例疑似主动脉夹层病人,男26例,女30例,平均年龄(55.9±11.2)岁,以CT血管成像(CTA)作为金标准,其中30例确诊为主动脉夹层,26例非主动脉夹层。采用χ2检验对2组间内膜瓣钙化内移、增宽的主动脉密度不均、管腔内线样高密度、主动脉横径增宽这4个主要CT平扫征象及伴随征象的差异进行比较,并对主要征象做诊断准确性分析。结果 主动脉夹层平扫的主要征象包括内膜瓣钙化内移(22例,39.3%)、增宽的主动脉密度不均(44例,78.6%)、腔内线样高密度(31例,55.4%)、主动脉横径局限性或广泛性增宽(36例,64.3%);伴随征象包括主动脉壁钙化(47例,83.9%)、病变累及分支血管管腔增粗(6例,10.7%)、心包积液(11例,19.6%)、胸腔积液(15例,26.8%)。主动脉夹层组的内膜瓣钙化内移和管腔内线样高密度发生率均高于非主动脉夹层组(均P<0.05);其中,内膜瓣钙化内移诊断主动脉夹层的敏感度66.7%,特异度92.3%,准确度78.6%;管腔内线样高密度的敏感度80%,特异度73.1%,准确度76.8%。2组其他CT征象比较差异无统计学意义(P>0.05)。结论 薄层CT平扫对急诊主动脉夹层的诊断具有重要提示意义。

The value of non-enhanced thin-slice CT in diagnosis of aortic dissection

Objective To explore the value of non-enhanced thin-slice CT in the diagnosis of aortic dissection.Methods All of 56 cases(26 males and 30 females,mean age 55.9±11.2 years)of suspected aortic dissection were retrospectively analyzed.CT angiography(CTA)was used as the gold standard,30 cases were diagnosed as aortic dissection,and 26 cases as non-aortic dissection.The four main plain CT signs(calcification,aortic density of widening,linear high density in lumen,and aortic diameter widening)and accompanying signs were compared between the two groups by using chi square test.The diagnostic accuracies using main signs were calculated.Results The main signs of aortic dissection on plain scan included calcification of intimal valve(22 cases,39.3%),uneven density of widened aorta(44 cases,78.6%),linear high density in lumen(31 cases,55.4%),and limited or extensive enlargement of aortic transverse diameter(36 cases,64.3%).The accompanying signs included calcification of aortic wall(47 cases,83.9%),thickening of branches and vessels(6 cases,10.7%),pericardium effusion(11 cases,19.6%),and pleural effusion(15 cases,26.8%).The frequencies of presenting those signs were significant difference between the two groups(P<0.05).The sensitivity,specificity and accuracy of endocardial valve calcification were 66.7%,92.3%and 78.6% respectively.The sensitivity,specificity and accuracy of high-density were 80%,73.1%and 76.8%respectively.There was no significant difference in other CT signs between the two groups(P>0.05).Conclusion Non-enhanced thin-slice CT plays an important role in the diagnosis of aortic dissection.