lation time between right heart and liver (RHLT). LTT for each lobe was used to evaluate the early portal hypertension. RHLT is useful in cirrhosis to detect liver areas missing portal inflow. We calculated the classical per-rectal portal shunt index (PRSI) at PRPS and the hepatic perfusion index (HPI) at LAS. RESULTS: The normal LTT value was 24 ± 1 s. Abnormal LTT had PPV = 100% for CLD. Twenty-seven noncirrhotic patients had LTT increased up to 35 s (median 27 s). RHLT (42 ± 1 s) was not related to liver disease. Cirrhosis could be excluded in all patients with PRSI < 5% (P < 0.01). PRSI > 30% had PPV = 100% for cirrhosis. Based on PRPS and LAS we propose the classification of CLD in 5 hemodynamic stages. Stage 0 is normal (LTT = 24 s, PRSI < 5%). In stage 1, LTT is increased, while PRSI remains normal. In stage 2, LTT is decreased between 16 s and 23 s, whereas PRSI is increased between 5% and 10%. In stage 3, PRSI is increased to 10%-30%, and LTT becomes undetectable by PRPS due to the portosystemic shunts. Stage 4 includes the patients with PRSI > 30%. RHLT and HPI were used to subtype stage 4. In our study stage 0 had NPV = 100% for CLD, stage 1 had PPV = 100% for non-cirrhotic CLD, stages 2 and 3 represented the transition from chronic hepatitis to cirrhosis, stage 4 had PPV = 100% for cirrhosis. CONCLUSION: LTT allows the detection of early portal hypertension and of opening of transhepatic shunts. PRSI is useful in CLD with extrahepatic portosystemic shunts. Our hemodynamic model stages the evolution of portal hypertension and portosystemic shunts. It may be of use in the selection of patients for interferon therapy. e a m , d e s i g n e d a n d c o o r d i n a t e d t h e s t u d y, m a d e t h e interpretation of the results, introduced the new parametersand classification, worked on the preparation and revision of the manuscript and on the statistical analysis of data; Balea IA assisted with the manuscript preparation and revision and the statistical analysis of data; Dina LA participated in the selection and follow up of the patients, the statistical analysis of the data and the evaluation of the per-rectal portal scintigraphy classical method based on the per-rectal portal shunt index; Piglesan CD, Tamas S as physicists were members of the investigation team; Grigorescu I participated in the selection and follow up of the patients and assisted with the statistical analysis of the data; Cotul SO is a retired honorary professor. As chief of laboratory before 2002 he introduced the classic per-rectal portal scintigraphy and liver angioscintigraphy into practice in this hospital and was a member of the investigation team.