Hepatic microcirculation of liver cirrhosis studied by corrosion cast/scanning electron microscope examination.

Changes of hepatic microcirculations in 22 autopsy cases of liver cirrhosis were analyzed by corrosion cast/scanning electron microscope (SEM) examination. By this method, the site of arterioportal (A-P) communication in liver cirrhosis was clearly demonstrated between proliferated portal venules and arterial capillaries. The communications were observed at the same site as in the normal liver and were not at larger arterial and portal vein branches. The findings indicate that the increase of A-P communication in liver cirrhosis may be called "capillary shunting". On the basis of the findings, it was postulated that the A-P shunt could not assist in the development of portal hypertension by the transmission of high arterial pressure to the portal vein but could only compensate for decreased portal flow and/or elevate the oxygen concentration in the sinusoids to improve the hypoxic state of the liver parenchyma. It was also demonstrated that the arterial capillarization of the interstitial septa in micronodular wide septal cirrhosis was more prominent than that in macronodular thin septal cirrhosis. A grade of portal vein reduction and compensatory arterialization in a fibrous septum have been regarded as an index to estimate the advancement of liver cirrhosis. Therefore, if alcoholic micronodular cirrhosis could change into macronodular, the process should have occurred at least before the establishment of micronodular wide septal cirrhosis.