OBJECTIVE Previous studies showed contrasting results with regard to alterations of regional cerebral blood flow/metabolism in subjects with liver cirrhosis. The aim of the study was to extend these findings in a larger series of patients. In addition, we wanted to determine whether such alterations are reversed by successful liver transplantation. METHODS The study group comprised 23 patients with liver cirrhosis and 13 normal controls. At entry to the study, all subjects underwent a complete neurological examination, EEG recordings and SPECT scanning. The severity of liver disease was determined according to the Child-Pugh score. Fourteen patients underwent a second SPECT examination 1 year after liver transplantation. RESULTS Significant rCBF reductions, ranging from 6% to 7%, were found in the majority of the cortical regions of the whole group of patients with cirrhosis, as compared to controls. These reductions were more diffuse in patients with alcoholic liver disease, comprising almost all the assayed regions. Liver transplantation normalized cortical rCBF deficits so that postoperative perfusion indexes were superimposable on control values. However, the frontal cortex remained significantly more impaired in patients with alcoholic cirrhosis than in those with non-alcoholic cirrhosis. The differences in frontal rCBF between the two groups of patients ranged from 6 to 11%. CONCLUSIONS Liver cirrhosis was associated with rCBF defects that depend upon the etiology of liver disease and that subsided after successful liver transplantation. The frontal defects in alcoholic cirrhosis either before or after surgery may imply a neurotoxic, possibly irreversible, action of ethanol.