Quantitative measurement of human tissue hepatic blood volume by C15O inhalation with positron‐emission tomography

In order to estimate the tissue liver function, tissue hepatic blood volume was measured quantitatively and non-invasively using C 15 O inhalation in conjunction with positron-emission tomography. Fifty-eight patients with normal liver function, 14 patients with chronic hepatitis, 28 patients with hepatic cirrhosis, and 4 patients with obstructive jaundice were studied by positron-emission tomography scan after the single breath inhalation of 20 mCi of high specific activity 15 O-labeled carbon monoxide. The mean tissue hepatic blood volume was significantly greater in patients with normal livers than in patients with chronic hepatitis or hepatic cirrhosis (mean : 20.5, 18.2, and 16.1 ml per 100 cm 3 , respectively, p=8.6x10 -8 ). Tissue hepatic blood volume (tHBV) correlated with the reaction of the mesenchymal system and protein synthesis, because there was a potent correlation between tHBV and hepatic fibrosis. In normal livers, we were able to demonstrate significant differences in tissue hepatic blood volume among liver segments.