Technetium Tc-99m disofenin
Technetium Tc-99m disofenin is a radiopharmaceutical agent used in hepatobiliary imaging for diagnostic purposes. It is well suited for both planar and single photon tomographic scintigraphy to quantitatively measure the function of liver, gallbladder and bile ducts and detect any anatomical changes in the hepatobliary system. It is available as an intravenous injection in a preparation kit under the name Hepatolite. Technetium Tc-99m is a metastable nuclear isomer and disofenin is an iminodiacetic acid derivative with no known pharmacologic actions at the doses recommended. However disofenin is the most commonly used iminodiacetic acid since it has a high liver to renal extraction and its hepatic uptake is not as highly dependent on serum bilirubin levels (a competitive inhibitor for liver uptake) as are other tracers from the iminodiacetic acid.