Schlund J F, Semelka R C, Kettritz U, Eisenberg L B, Lee J K
Department of Radiology, University of North Carolina, School of Medicine, Chapel Hill 27599-7510, USA.
J Magn Reson Imaging. 1995 Jul-Aug;5(4):375-7. doi: 10.1002/jmri.1880050402.
The purpose of the present study was to demonstrate the frequency of occurrence of transient increased segmental hepatic enhancement distal to portal vein obstruction in patients with a lobar (main branch) portal vein obstruction. MR images of all patients with main and lobar branch portal vein obstruction examined by dynamic gadolinium enhanced gradient echo MR images between December 1990 and July 1994 were reviewed retrospectively. All studies included T2-weighted imaging, T1-weighted spoiled gradient echo 'fast low angle shot ([FLASH])', and postgadolinium enhanced FLASH imaging at 1, 45, and 90 sec and 10 min. Fourteen patients were identified with portal vein obstruction which included: six with main portal and right and left branch occlusion, six with right lobar, and two with left lobar. In the six patients with main portal vein obstruction, enhancement on 1-sec postgadolinium FLASH images was homogenous (three patients), diffusely heterogeneous (two patients), or peripherally hyperintense (one patient). In eight of eight patients with isolated obstruction of the right or left lobar portal vein, transient-increased segmental enhancement distal to portal vein occlusion was observed on immediate postcontrast images. Relatively high signal intensity of the involved segments was present on 1-sec images and liver parenchymal enhancement became more homogeneous by 45 to 90 sec in all cases. In conclusion, transient-increased segmental enhancement occurred in eight of eight patients with isolated right or left portal vein occlusion. We postulate that this effect occurs due to increased hepatic arterial blood flow in the presence of portal vein obstruction.
本研究的目的是证实叶（主分支）门静脉梗阻患者门静脉梗阻远端节段性肝脏一过性强化的发生率。回顾性分析了1990年12月至1994年7月间通过动态钆增强梯度回波磁共振成像检查的所有主分支和叶分支门静脉梗阻患者的磁共振图像。所有研究均包括T2加权成像、T1加权扰相梯度回波快速低角度激发（[FLASH]）成像，以及钆增强后1秒、45秒、90秒和10分钟时的FLASH成像。确定了14例门静脉梗阻患者，其中包括：6例主门静脉及左右分支闭塞，6例右叶梗阻，2例左叶梗阻。在6例主门静脉梗阻患者中，钆增强后1秒FLASH图像上的强化表现为均匀（3例）、弥漫性不均匀（2例）或周边高信号（1例）。在8例孤立性右或左叶门静脉梗阻患者中，8例在对比剂注射后即刻图像上均观察到门静脉闭塞远端节段性一过性强化。所有病例中，受累节段在1秒图像上均呈现相对高信号强度，至45至90秒时肝实质强化变得更加均匀。总之，8例孤立性右或左门静脉闭塞患者中均出现节段性一过性强化。我们推测这种效应是由于门静脉梗阻时肝动脉血流增加所致。
