胆道系统扩张的MRI诊断

MR Diagnosis of Dilated Biliary Duct.

本文回顾性分析了胆道扩张的MR表现,认为MR对胆管扩张的检出十分敏感。T_1加权成像时,肝内胆管扩张呈树枝状低信号影,近肝门处此影愈粗。T_2加权成像时,则树枝状影呈高信号,且能检出更多肝周细小扩张的胆管。肝外扩张的胆管,横断面T_1、T_2加权成像分别呈低或高信号的圆形影。MRI 对判断胆管扩张的平面亦十分准确,但对确定梗阻的原因还有一定限度。

The manifestations of dilated biliary ductswere reviewed retrospectively in this article.Authors thought that MRI is a very sensitivemethod for detecting dilated biliary ducts.On T_1-weighted image,dilated intrahepaticalbiliary ducts appear as a branch-likedstructure with hypointensity,which is biggerin diameter near the hepatic porta.On T_2weighted image,the branch-liked structurebecome hyperintensity and more small borebiliary ducats are demonstrated in theperiphery of liver.Dilated extrahepaticbiliary ducts appear as round structures withhypo-or hyperintensity on transaxial T_1-orT_2-weighted images.The obstructed level ofbiliary ducts was determinted accuratedlywith MRI.But some limitation still exists indefining obstructed causes.