Abdominal halo in Tc-99M DISIDA hepatobiliary scintigraphy: a sign of massive ascites.

An abdominal halo was demonstrated in a Tc-99m di-isopropyl imminodiacetic acid (DISIDA) hepatobiliary scintigram of a patient with a long history of alcohol abuse and liver disease complicated by massive ascites. This halo was not observed in the concurrent Tc-99m sulfur colloid study. Large amounts of ascitic fluid floated the liver, the bowel and the mesentery in the central abdomen forming an abdominal halo, a band-like clear zone around the abdominal organs. Severe hepatic dysfunction, resulting in prolongation of the blood pool phase in the Tc-99m DISIDA study, will cause exaggeration of this finding. When an abdominal halo is seen it should be considered a sign of massive ascites.