A test for evaluation of peritoneo-venous shunt function: concise communication.

A simple imaging procedure has been devised for patients with peritoneovenous shunts when ascites reaccumulates and a decision must be made on whether or not to revise the shunt. A dose of 99mTc-sulfur colloid is injected into the peritoneal cavity and imaging of the abdomen and chest is performed 30 and 60 min later. After checking for tracer distribution throughout the peritoneal cavity, one looks for radioactivity in the liver and spleen and in the anterior chest tube. With a properly functioning shunt and effective breathing exercises, these are easily identifiable. If the shunt is obstructed, tracer activity will remain in the peritoneal cavity and thus cannot be identified in the liver or spleen.