MRI、CT影像学表现差异在肝脏孤立性坏死结节中的诊断价值

Diagnostic value of MRI and CT in liver solitary necrotic nodule

目的探讨肝脏孤立性坏死结节(SNN)的MRI、CT影像学表现及诊断价值。方法选取2014年1月~2020年6月在我院就诊的肝脏SNN患者40例,其中接受MRI检查的22例患者作为MRI组,CT检查的18例患者作为CT组,分析MRI、CT诊断肝脏SNN的价值,同时分析单纯凝固性坏死型、伴液化性坏死型和多结节融合型病灶的MRI、CT影像学表现差异。结果MRI诊断肝脏SNN准确率为95.45%,明显高于CT组(P<0.05);CT组,单纯凝固性坏死型、伴液化性坏死型和多结节融合型病灶CT平扫及增强扫描表现差异无统计学意义(P>0.05),单纯凝固性坏死型、伴液化性坏死型和多结节融合型病灶CT平扫主要呈低密度影,分别占83.33%、42.86%和40.00%,3种病灶均无强化,其中分别有83.33%、57.14%和80.00%病灶包膜延迟强化;MRI组,伴液化性坏死型T2WI序列低信号比例高于单纯凝固性坏死型和多结节融合型(P<0.05),多结节融合型T2WI序列稍高信号比例高于伴液化性坏死型(P<0.05),单纯凝固性坏死型、伴液化性坏死型和多结节融合型病灶T1WI序列低信号比例均为100.00%,T2WI序列低信号鉴别伴液化性坏死型SNN的敏感度为100.00%,特异性为78.57%,准确率为86.36%,阳性预测值为72.73%,阴性预测值为100.00%;T2WI序列序列稍高信号鉴别伴液化性坏死型鉴别多结节融合型SNN的敏感度为100.00%,特异性为68.75%,准确率为77.27%,阳性预测值为54.55%,阴性预测值为100.00%,单纯凝固性坏死型、伴液化性坏死型和多结节融合型动脉期、门脉期和延迟期病灶无强化比例均为100.00%,但延迟期所有病灶边缘有强化。结论MRI和CT在肝脏SNN诊断中有一定应用价值,其中MRI诊断价值较好。

Objective To investigate the MRI and CT findings and diagnostic value of solitary necrotic nodule(SNN)of the liver.Methods Forty cases of liver SNN patients in our hospital from January 2014 to June 2020 were selected,including 22 cases of MRI examination(MRI group)and 18 cases of CT examination(CT group).The value of MRI and CT in the diagnosis of liver SNN were analyzed.The differences of MRI and CT images of simple coagulative necrosis type,liquefying necrosis type and multi nodule fusion type were analyzed.Results The accuracy of MRI in diagnosing liver SNN was 95.45%,which was significantly higher than that in CT group(P<0.05).In the CT group,there was no significant difference in the plain and enhanced CT findings of the simple coagulation necrosis type,liquefaction necrosis type and multi nodule fusion type(P>0.05).The lesions of simple coagulation necrosis,liquefaction necrosis and multi nodule fusion showed low density on plain CT scan,accounting for 83.33%,42.86%and 40.00%.There was no enhancement in the three types of lesions,including 83.33%,57.14% and 80.00% of the capsule of lesions had delayed enhancement.In MRI group,the low signal ratio of T2WI in liquefying necrosis was significantly higher than that of coagulation necrosis and multi nodule fusion(P<0.05).The proportion of slightly high signal in T2WI of multi nodule fusion type was significantly higher than that of liquefaction necrosis type(P<0.05).The low signal ratio of T1WI sequence in the single coagulable necrosis type,liquefaction necrosis type and multi-nodule fusion type lesions was 100.00%.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of T2WI sequence low signal for the identification of SNN with liquefaction necrosis were 100.00%,78.57%,86.36%,72.73% and 100.00% respectively.The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of slightly higher signal of T2WI sequence identifies SNNs with multi-nodular fusion were 100.00%,68.75%,77.27%,54.55% and 100.00%,respectively for the identification of SNN with liquefaction necrosis.The proportion of lesions of the necrotic type,liquefactive necrosis type and multi-tuberculous fusion without enhancement at the arterial,portal and delayed stages was 100.00%,but there was enhancement in the edge of all lesions at the delayed stage.Conclusion MRI and CT have certain application value in the diagnosis of liver SNN,among which MRI has better diagnostic value.