The Use of Carbon Dioxide Wedged Hepatic Venography to Identify the Portal Vein: Comparison with Direct Catheter Portography with Iodinated Contrast Medium and Analysis of Predictive Factors Influencing Level of Opacification

CO2 WHV is safe, highly efficient, and reliable in the identification of the right and left portal veins. CO2 WHV is clearly less effective in opacifying the entire portal main trunk. With use of CO2 WHV, the portal venous system is most distinctly opacified in patients presenting with a high portosystemic gradient, a spontaneous splenorenal shunt, esophageal varices, and reversed portal flow.