MRI 3D-VIBE序列联合MRCP在胰胆管十二指肠连接区癌鉴别诊断中的价值

Differential Diagnosis of Pancreaticobiliary Ductal and Duodenal Union Carcinomas with MRI 3D-VIBE Sequence Combined with MRCP

目的探讨磁共振三维容积式内插值法屏气检查(MRI 3D-VIBE)序列联合磁共振胆胰管成像(MRCP)在胰胆管十二指肠连接区癌(PDDUC)诊断和鉴别诊断中的价值。方法59例经手术病理或临床随访证实的PDDUC患者(胰头癌34例,胆总管下段癌14例,壶腹癌11例),行常规MRI、MRCP及3D-VIBE动态增强扫描,观察肿瘤形态学特点;计算病灶的信噪比(SNR)及对比噪声比(CNR);测量胰胆管汇合角、胰胆管末端间距、十二指肠主乳头至扩张的胰胆管末端的距离、胆总管直径、胰管直径。结果胰头癌、胆总管下段癌和壶腹癌3组间病灶最大径、中心位置、边缘情况和病灶均匀度,差异有统计学意义(P<0.05)。胰头癌较易累及胰周血管,胆总管下段癌和壶腹癌均未见邻近血管受累征象。胰头癌组的胰胆管汇合角度、十二指肠主乳头至胰胆管梗阻端的距离及胰胆管末端间距均大于胆总管下段癌和壶腹癌组;"四管征"多见于胰头癌。门脉期胆总管下段癌SNR高于胰头癌和壶腹癌组(P<0.05),动脉早期和动脉晚期3组间比较差异无统计学意义。门脉期胆总管下段癌信号强度稍高于胰腺实质。结论MRI 3D-VIBE序列联合MRCP能较好显示不同类型PDDUC的形态学特征和强化特点,能较好显示胰胆管的细微差别,有助于胰头癌、胆总管下段癌和壶腹癌的诊断和鉴别诊断。

Objective To evaluate the value of MRI 3-dimensional volumetric interpolated breath-hold examination（VIBE） sequence combined with MR cholangiopancreatography（MRCP） in the differential diagnosis of pancreaticobiliary ductal and duodenal union carcinomas（PDDUC）.Methods Fifty nine patients with PDDUC confirmed by surgical-pathological findings or unequivocal clinical follow-up results were recruited in the study,which included 34 pancreatic head carcinomas,14 distal common bile duct carcinomas,and 11 ampullary carcinomas.In addition to the routine MRI examinations for the upper abdomen,MRCP and Gadolinium-enhanced 3D-VIBE tri-phase（early arterial phase,late arterial phase and portal venous phase） were performed.The morphological features of the lesions,the signal-to-noise ratio（SNR） and contrast-to-noise ratio（CNR） of the lesions were analyzed.The distance between the ends of the dilated pancreaticobiliary duct,the distance from the duodenal lumen to the distal end of the dilated duct,the diameter of the common bile duct and the pancreatic duct were measured.Results The differences among the carcinomas in max-diameters,locations,edge features and degrees of signal equality of the lesions showed statistical significance（P〈0.05）.The percentage of peripancreatic vascular involvement was significantly higher in the pancreatic head carcinoma than in the others.The pancreaticobiliary conjunction angle,the distance between the ends of dilated pancreaticobiliary ducts,the distance from the duodenal lumen to the distal end of dilated duct were larger in the pancreatic head carcinoma than in the distal common bile duct carcinoma and ampullary carcinoma.The pancreatic head carcinoma showed four-segment signs.During portal venous phase,the mean SNR of the distal common bile duct carcinoma was higher than the pancreatic head carcinoma and ampullary carcinoma（P〈0.05）,while in the other phases,no statistical significant differences were found（P〉0.05）.The signal intensity of distal common bile duct carcinoma was higher than the pancreatic head parenchyma during portal venous phase.Conclusion MRI 3D-VIBE sequence combined with MRCP can demonstrate the morphologic features and enhancement characteristics of PDDUC,and display the details of abnormalities of pancreaticobiliary duct.It is valuable in the differential diagnosis of pancreatic head carcinoma,distal common bile duct carcinoma and ampullary carcinoma.