An experimental study of percutaneous absolute ethanol injection therapy for small hepatocellular carcinoma: effects of absolute ethanol on the healthy canine liver.

As a basic study of percutaneous ethanol injection therapy (PEIT) under ultrasound guidance, 1 ml of absolute ethanol was injected into the healthy liver of adult mongrel. Ultrasonographic, macroscopic and histologic studies of the injection site were carried out chronologically and the mechanism for cell necrosis was evaluated. It was concluded that absolute ethanol injected to the healthy mongrel liver caused not only direct cell damage due to potent fixative effect through deprivation of fluid from cells, but also indirect cell damage due to impairment of tissue blood flow related to thrombus formation, which resulted in necrosis. Moreover, disappearance of acoustic shadow (AS) was considered to be due to absorption or removal of the gases, which were the air in the PTC needle injected into the liver and the evaporated oxygen from denatured oxyhemoglobin (HbO2), and the denatured red blood cells after improvement of blood flow at the surrounding area of the injection site. Gradual attenuation of the echogenicity might reflect the progression of necrosis at the injection site recognized histologically.