目的探究多层螺旋CT(MSCT)及 核磁共振成像(MRI)在肝外胆管结石诊 断中的应用价值，并分析其漏诊原因。 方法 收集我院行ERCP术前2周内，同时 行MSCT、MRI及MRCP检查的120例疑似肝 外胆管结石患者临床资料进行回顾性分 析，比较MSCT及MRI的诊断价值，并分析 MSCT、MRI漏诊特征。结果 ①MRI诊断 肝外胆管结石的灵敏度、阴性预测值高 于MSCT，漏诊率低于MSCT，差异有统计 学意义(P<0.05)。②MSCT：密度<40HU的 结石漏诊率显著高于40HU-60HU及>60HU 两组，差异有统计学意义(P<0.05)；密 度40HU-60HU组中结石<0.5cm的漏诊率显 著高于0.5-1.0cm、>1.0cm两组，差异有 统计学意义(P<0.05)；密度>60HU组中结 石<0.5cm、0.5-1.0cm、>1.0cm的漏诊率 比较，差异无统计学意义(P>0.05)；密 度40HU～60HU组及密度>60HU组中，胆 总管扩张与无胆总管扩张患者的漏诊率 比较，差异均无统计学意义(P>0.05)。 ③MRI：泥沙样结石漏诊率显著高于<5mm 结石、>5cm结石两组，差异有统计学意义 (P<0.05)；无肝外胆管扩张患者的漏诊率 显著高于肝外胆管扩张患者，差异有统计 学意义(P<0.05)。结论 临床高度怀疑肝 外胆管结石的患者在条件允许的情况下首 选MRI检查。MSCT与MRI对肝外胆管结石的 诊断均受结石大小、位置、胆总管扩张情 况等多重因素影响。

Objective To explore the application value of multi-slice spiral CT (MSCT) and magnetic resonance imaging (MRI) in the diagnosis of extrahepatic bile duct stones and to analyze the reasons for the missed diagnosis. Methods The clinical data of 120 patients with suspected extrahepatic bile duct stones who underwent MSCT, MRI, and MRCP examinations at the same time within 2 weeks before ERCP were retrospectively analyzed in our hospital. Diagnostic values of MSCT and MRI were compared, and the features of missed diagnosis of MSCT and MRI were analyzed. Results The sensitivity and negative predictive value of MRI were higher than those of MSCT in the diagnosis of extrahepatic bile duct stones while the missed diagnosis rate was lower than that of MSCT (P<0.05). MSCT: The missed diagnosis rate of stones with density<40 HU was significantly higher than that of stones with density of 40HU-60HU and>60HU (P<0.05). The missed diagnosis rate of stones<0.5cm in the 40HU-60HU group was significantly higher than that of stones with 0.5-1.0cm and >1.0cm (P<0.05). In density>60HU group, there was no statistically significant difference in the missed diagnosis rates of stones<0.5cm, 0.5-1.0cm and >1.0cm (P>0.05). There was no significant difference in the missed diagnosis rate of patients with bile duct dilatation or without bile duct dilatation between the 40HU-60HU group and the density>60HU group (P>0.05). MRI: The missed diagnosis rate of muddy stones was significantly higher than that of<5mm stones and>5cm stones (P<0.05). The rate of missed diagnosis in patients without extrahepatic bile duct dilation was significantly higher than that in patients with extrahepatic bile duct dilatation (P<0.05). Conclusion Patients with clinically suspected extrahepatic bile duct stones should prefer MRI if conditions permit. The diagnosis of extrahepatic bile duct stones by MSCT and MRI is influenced by multiple factors, such as the size and location of stones and common bile duct dilatation.