Selective portal vein embolization with absolute ethanol induces hepatic hypertrophy and makes more extensive hepatectomy possible

Portal vein embolization has been used recently to decrease the amount of the liver to be resected and to enhance the function of the remaining hypertrophied lobes. We have observed a strong contact destructivity of absolute ethanol and used it for portal vein embolization. The present study was performed to produce hepatic hypertrophy and to show histopathologic changes that follow ethanol embolization of rat liver. Hepatic proliferation and histopathology were studied in rats receiving low and high doses of absolute ethanol via portal vein and rats undergoing 70% hepatectomy alone. The liver weight of the unresected and unembolized lobes increased rapidly after embolization and hepatectomy. Although the increase was more rapid in the high-dose group than the low-dose group in early days, the final results were not different from each other and were almost equal to those after hepatectomy. Complete obstruction of portal venous branches and massive necrosis were the main histopathologic observations after portal vein embolization with all doses of ethanol. Because the mortality rate in the low-dose group was lower than in the high-dose group and extensive necrosis of the liver parenchyma and subsequent regeneration was sufficient, using minimum dose of ethanol was much safer. Based on the biochemical and hematologic parameters, portal vein embolization with low-dose ethanol did not impair liver function more than hepatectomy alone during the initial 14 days. Portal vein embolization with absolute ethanol makes more extensive hepatectomy possible by reducing the volume necessary to resect and preserves the function of the remaining liver.