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

Objective: To evaluate the clinical value of the diagnoses of extrahepatic biliary tract obstruction by 3D FRFSE sequence 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 1.5T 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 LAVA 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 diagnosed skeptical tumors.