野村 康晴¹, 松田 康雄², 藪内 以和夫¹, 西岡 稔¹, 田村 信司³

Yasuharu NOMURA¹, Yasuo MATSUDA², Iwao YABUUCHI¹, Minoru NISHIOKA¹, Shinji TAMURA³

¹大手前病院内科, ²大手前病院外科, ³大阪大学第二内科

¹Department of Internal Medicine, Otemae General Hospital, ²Department of Surgery, Otemae General Hospital, ³2nd Department of Internal Medicine, Osaka University Medical School

キーワード : Enhanced Ultrasonography, Contrast agent, Helium, Hepatic tumors

We previously reported that the Enhanced Ultrasonography (EU) with carbon dioxide (CO₂) microbubbles was useful for the diagnosis of hepatic tumors. Recently, we applied helium gas (He) microbubbles as a new contrast agent for EU.
Before the clinical challenge, we examined the acute toxicity for the organs using a experimental dog. No apparent histological change of its liver and lung was found before and after the injection of the He microbubbles into the hepatic artery.
The contrast enhancement of hepatic tumors by He-EU was just as effective as that by CO₂-EU. The effect of enhancement of hepatocellular carcinomas (HCC) by He-EU continued longer than that by CO₂-EU, 12.8±4.18 min., and 3.5±1.62 min., respectively (pMoreover, after the disappearance of contrast enhancement of the non-tumorous liver parenchyma, hepatic tumors were still clearly observed for over 30 min.
After the complete enhancement of the total hepatic parenchyma by the He microbubbles, the back flow of contrast agents to the splenic artery was observed. This phenomenon suggested that the He microbubbles filled the hepatic artery and blocked its blood flow.
The He microbubbles, used with some anticancer agents, may be expected to have some chemoembolization effects on hepatic tumors.