Gadolinium-Enhanced Phase-Contrast Magnetic Resonance Portography

Abstract

Purpose: The purpose of this study was to investigate the eŠect and usefulness of gadolinium-chelated contrast medium in phase-contrast magnetic resonance (MR) portography.Methods: Twenty-six patients (21 men, 5 women; aged 34 to 79 years, mean 62 years) underwent respiratory-triggered 3-dimensional phase-contrast portography before and after administration of gadolinium in a 1.5T MR unit. Coronal maximum intensity projection (MIP) images of the portal vein were reconstructed and compared to conventional arterial portograms regarding visualization. Signal-to-noise ratio (SNR) and portal vein-to-liver contrast-to-noise ratios (CNR) of main, right, right anterior, right posterior, left portal veins, and umbilical portion were measured on both non-enhanced and gadolinium-enhanced images and compared.Results: Portal veins and branches were more clearly visualized on the gadoliniumenhanced than on the non-enhanced images. Compared to arterial portography, gadolinium-enhanced portography showed similar performances in visualization, except in the right posterior branch and left portal vein. No severe image degradation from respiration was experienced. SNR was signiˆcantly higher on the gadolinium-enhanced than on non-enhanced images except in the right anterior branch. CNR was signiˆcantly higher on the gadolinium-enhanced than on the non-enhanced images at all measured locations.Conclusions: Administration of gadolinium improves the SNR and CNR of phasecontrast portography and visualization of the portal vein. The phase-contrast technique with gadolinium enhancement can be used to evaluate the portal vein as a supplemental technique.

MR-based Measurements of Portal Vein Flow and Liver Stiffness for Predicting Gastroesophageal Varices

“…[16][17][18][19][20][21] MR examination of the liver can be shortened by performing both PC-MRI and MRE during the delay before equilibrium-or hepatocyte-phase after administration of a contrast agent. 22,23 Use of these examinations to predict GEV would signiˆcantly enhance the utility of MR imaging in managing patients with cirrhosis.…”

Preoperative imaging of left portal vein at the Rex recess for Rex shunt formation using wedged hepatic vein carbon dioxide portography

“…It can, however, be difficult to image the Rex segment in children because of small size of the intrahepatic portal vein radicals, the presence of multiple collaterals, and poor inflow. In the presence of cavernous transformation, indirect arterioportography and splenoportography are unreliable because of the obstruction to blood flow, reversal of flow, and dilutional effects, and cross-sectional imaging with computed tomography and MRI can evaluate the extrahepatic portal vein [14][15][16][17][18][19]. Direct transhepatic portography is relatively invasive and would be technically challenging in small children and may fail to show the Rex segment if there is no communication between the left and right portal veins.…”

MR Evaluation of Portal Hypertensive Collateral Shunting Vessels for Predicting Outcome after Transjugular Intrahepatic Portosystemic Shunt

“…Preprocedural cross-sectional imaging of the liver and portal system can detect important contraindications to TIPS placement, such as multiple or huge hepatic cysts or hepatocellular carcinomas or obstruction or thrombosis of the portal or hepatic veins. 1,[9][10][11][12][13][14] Many researchers have investigated the relationships between diameter of the portal vein and portal pressure, 16 ‰ow direction, 17 development of the shunting vessels, 18 diameter of the shunting vessels and gastroesophageal bleeding, 19 or onset of encephalopathy. 20 Ito and associates 21 recently reported decreased diameter and hepatopetal ‰ow of the left gastric vein and the presence of non-variceal portosystemic shunt as predictive factors for variceal relapse after endoscopic therapies.…”

“…[9][10][11][12][13][14] We aimed to assess whether MR imaging evaluation of portosystemic collateral shunts can be used to predict therapeutic eŠectiveness of, complications after, and technical di‹culty during TIPS creation.…”