Diagnosis of sclerosing cholangitis (SC) by Tc-99m-disida SPECT imaging

The role of planar scintigraphy and SPECT as a non-invasive imaging modality was assessed critically in the diagnosis of SC, a condition characterized by segmental narrowing and dilatation of intra and extra hepatic biliary ducts. Five normal subjects and 10 patients with cholangiographically documented SC were studied with 3 to 5 mCi of Tc-99m-DISIDA. Planar images were obtained. The tomographic images were reconstructed in transaxial, sagital and coronal planes. The tomo images and planar scintigraphy were then compared with cholangiograms to identify the exact sites of involvement. Tomo and planar scintigraphy showed homogeneous uptake and uniform excretion from all liver regions in normal subjects. In SC, the uptake was inhomogeneous and half-time excretion showed wide regional variation. SPECT images displayed dilated ducts as bile pooling and correctly identified ducts involved in the cholangiograms. The authors concluded that planar and SPECT scintigraphy offer a new non-invasive method for detection of SC and that the measurement of excretion half-time may offer a better objective parameter in following the course of therapy for SC.