The article presents information on a 99mTc-RBC scintigraphy. In the study, a 47-year old asymptomatic woman with chronic elevation of aminotransaminases was referred for scintigraphic study to evaluate the vascularity of an extrahepatic mass, detected by ultrasonography in the hilum of the liver. 99mTc-RBC scintigraphy demonstrated extrahepatic portal vein aneurysm. The early filling of the lesion in the dynamic phase was compatible with an increased blood flow inside the mass.