Cavo-portal shunting in superior and inferior vena caval obstruction.

Focal radionuclide accumulation of Tc-99m sulfur colloid (SC) and tc-99m macroaggregated albumin (MAA) in the liver has been reported in both inferior and superior vena caval obstruction. We studied a patient with uniform radionuclide accumulation of Tc-99m MAA in the liver during lung scintigraphy. In this patient, both the superior vena cava (SVC) and the inferior vena cava (IVC) were obstructed. Most of the systemic venous return appeared to be passing through the liver on its way to the heart, through the anastomoses between the systemic veins and the portal vein. The the best of our knowledge, uniform hepatic uptake in vena caval obstruction is not reported in the literature.