Abstract
A modification of the test procedure for evaluation of the peritoneo-venous shunt is described. When Tc-99m sulfur colloid is introduced by intraperitoneal injection, scintiphotos of a patent shunt can usually be obtained immediately after injection. If the shunt is not visualized immediately, a liver scan must be obtained to distinguish ascitic fluid from functioning liver tissue. Cases in which this technique has been used show it to be a reliable method for assessing peritoneo-venous shunt patency.