肝内门静脉和肝静脉的解剖与变异(三维动态增强磁共振血管成像分析)

目的用三维动态增强磁共振血管成像（３ｄｉｍｅｎｔｉｏｎａｌｄｙｎａｍｉｃｃｏｎｔｒａｓｔｅｎｈａｎｃｅｄＭＲＡ，３ＤＤＣＥＭＲＡ）前瞻性地观测肝内门静脉（简称门脉）和肝静脉的解剖和变异。方法共进行１４２例门脉和肝静脉３ＤＤＣＥＭＲＡ检查。对肝内门脉和肝静脉的解剖和变异做分型，计算每一型所占总调查人数的比例，并计算右后下肝静脉的显示率。结果１４２次成像中，８例（５．６％）显示门脉呈三分叉状，７例（４．９％）门脉先分出右后支，然后上行分为左支和右前支，４例（２．８％）门脉右前支源于左支，未发现有门脉左支水平段或右支缺如，余下１２３例（８６．６％）显示正常门脉分支。绝大多数情况下（９５．１％）肝中、肝左静脉合并，而三大支肝静脉单独汇入下腔静脉仅占４．９％。右后下肝静脉的显示率为７．７％。结论肝内门脉变异并不少见。肝中和肝左静脉多合并后汇入下腔静脉。部分病人有较为粗大的右后下肝静脉。３ＤＤＣＥＭＲＡ能方便而清楚地显示上述血管的解剖和变异

Anatomy and variations of the intrahepatic portal vein and hepatic veins: observations based on 3D DCE MRA

Objective A prospective 3dimensional dynamic contrast enhanced MRA (3D DCE MRA) study was undertaken to determine the anatomy and variations of the intrahepatic portal vein and hepatic veins. Methods 142 3D DCE MRA of the portal and hepatic venous systems were analyzed. The normal anatomy of these venous systems was determined. Variants of the intrahepatic portal veins were classified. The percentage of each variation was calculated. The visualization rate of the right posterior inferior hepatic vein was measured. Results Of the 142 patients examined, 8(5.6%) had trifurcation, 7 (4.9%) had a right posterior branch arising from the main portal vein first and then the right anterior and left portal vein originating from the ascending main portal vein, 4(2.8%) had a right anterior branch from the left portal vein, and the absence of the horizontal segment of the left portal vein or absence of the right portal vein was not demonstrated. The remaining 123 (86.6%) patients had normal distribution of the intrahepatic portal vein. In the majority of cases (95.1%), the middle hepatic vein formed a common trunk with the left hepatic vein, while the three major hepatic veins were independent in 4.9% cases. The visualization rate of the right posterior inferior hepatic vein was 7.7%. Conclusions Variations of the intrahepatic portal vein branching are not rare. The middle and left hepatic veins frequently share a common trunk. Some patients have relatively largesize right posterior inferior hepatic vein. The anatomy and variations of the portal and hepatic veins are easily recognized with 3D DCE MRA.