MRCP、FIESTA序列和LAVA序列动态增强扫描诊断肝外胆道梗阻的对比研究

Comparative study of MRCP,FIESTA and dynamic enhanced LAVA sequences in the diagnosis of extrahepatic biliary obstruction

目的:评价FSE序列MRCP、FIESTA序列和LAVA动态增强扫描诊断肝外胆道梗阻的临床价值。方法:对50例经超声诊断肝外胆道梗阻的患者,以1.5T HD MR行FSE序列MRCP、FIESTA序列冠状位扫描,并以LAVA序列行冠状动态增强扫描,分别在注射Gd-DTPA后10、30和60s行3期冠状位扫描,将FIESTA序列图像及LAVA序列动态增强图像、MRCP诊断结果与手术病理进行对比。结果:MRCP可以显示梗阻的部位以及可能的病因,但对病变的侵犯范围显示能力有限;FIESTA序列可以显示梗阻的部位、胆管与门静脉的关系,显示胆管结石有较大的价值,但对胆管的肿瘤、胰头部肿瘤显示能力不足;LAVA序列动态增强扫描对恶性肿瘤所致的梗阻有较强的诊断能力,尤其是在诊断肿瘤的侵犯范围方面有较大的临床意义。结论:肝外胆道梗阻的MRI检查可先行FIESTA序列扫描及MRCP扫描,对疑诊断肿瘤的患者可行LAVA序列动态增强扫描。

Objective： To evaluate the clinical value of the diagnoses of extrahepatic biliary tract obstruction by 3D FRFSE se- quence of MRCP, 2D FIESTA sequence and 3D dynamic enhancement scans of LAVA sequence. Methods： A total of 50 patient with extrahepatic biliary tract obstruction who were diagnosed by ultrasound were scanned by GE Signa EXCITE 1. ST HD Echospeed MR（GE Milwaukee）,each was followed by coronal scanned,which included three period,20,40 and 60 seconds after injecting Magnevist（schering pharmaceutical Ltd）, using 3D FRFSE sequence of MRCP, 2D FIESTA sequence,and 3D dynamic enhancement scans of I.AVA sequence. Compared the pathology of the operations with the images of 2D FIESTA sequence,the 3D dynamic enhancement images of LAVA sequence and the results of 3D FRFSE MRCP. Results.. 2D FIESTA sequence can display the locations of the obstruction,the relationship between biliary tract and portal vein. Displaying calculus of bile duct is of great value,but the capability of displaying the tumors of biliary tract and head of pancreas is not very high. 3D FRFSE MRCP can display the locations of the obstruction and the potential etiopathogenisis, but the capability of displaying the invasive range of the affection is so limited. The 3D dynamic enhancement scans of LAVA sequence have a better diagnostic capability of obstructions which is resulted by malignant tumors,especially have a better clinical significance in diagnosing the invasive range of the tumors. Conclusions：The examinations of extrahepatic biliary tract obstruction are scanned by 2D FIESTA sequence and 3D FRFSE MRCP firstly,and then using the 3D dynamic enhancement scans of LAVA sequence to the patients,who are diag- nosed skeptical tumors.