Sequential liver scanning was introduced for the diagnosis of medical and surgical jaundices by Yamada and Taplin(1) using I-131-Rose Bengal. Following this trial authors have reevaluated the I-131-BSP (monoiodide)(2) and applied this dye successfully for the same purpose as well as for hepatic function study(2). In this paper, taking note of the fact that I-131-BSP sequential scanning method makes visible the mechanism of liver uptake, intrahepatic transport and biliary excretion of this dye, the authors aimed to make clear the classification of constitutional hyperbilirubinemias and the pathophysiology of this disease subjects, which are still controversial among researchers.