Classifying choledochal cysts using hepatobiliary scintigraphy

Purpose: This retrospective study was designed to classify choledochal cyst s on the basis of the findings of hepatobiliary scintigraphy. Methods: Twenty-one patients with choledochal cysts (15 female, 6 male; mea n age, 20 years) proved on the findings of endoscopic retrograde cholangiop ancreatography (ERCP) or surgery and histopathologic analysis were included in the study. Two nuclear medicine physicians, blinded with regard to chol angiographic and operative details, were asked to review and to classify th e type of choledochal cyst seen on the hepatobiliary scan. Later, scintigra phic results were compared with ERCP and surgical findings for a reference standard. Results: The findings of hepatobiliary scintigraphy correlated with ERCP an d surgical findings in 18 of 21 cases (86%). Scintiscans correctly identifi ed all type 1 cysts (12/12). The sensitivity of scintigraphy in diagnosing type 4 cysts was 66% (6 of 9 cases). It underestimated the intrahepatic ext ent of disease in type 4a biliary cysts (37%). Conclusion: This study illustrates the utility of hepatobiliary scintigraph y in diagnosing type 1 and 4 choledochal cysts.