Yoshimoto Tsuyoshi, Kotoh Kazuhiro, Horikawa Yuki, Kohjima Motoyuki, Morizono Shusuke, Yamashita Shinsaku, Enjoji Munechika, Nakamuta Makoto
Department of Medicine and Bioregulatory Science, Graduate School of Medical Science, Kyushu University, Fukuoka, Japan.
Liver Int. 2007 Apr;27(3):368-72. doi: 10.1111/j.1478-3231.2007.01454.x.
BACKGROUND/AIMS: Although radio frequency ablation (RFA) has been widely accepted as an effective treatment for hepatocellular carcinoma (HCC), severe complications are not uncommon. Major complications seem to occur as a result of over-ablation beyond the intended area. As most patients with HCC have underlying cirrhosis, we speculated that decreased portal flow might cause the necrosis associated with RFA. To confirm this hypothesis, we examined the area of necrosis resulting from RFA under varying conditions of portal flow in a porcine model.
RFA was performed using ultrasonographic guidance in anesthetized pigs. During the RFA procedure, portal flow was regulated by a balloon catheter, which was set in a portal trunk. The necrosis area was measured after sacrifice and was compared with the hyperechoic area that appeared during ablation. In another session, RFA was performed close to the hepatic vein and endothelial damage was examined.
The necrosis area caused by RFA was significantly larger when the portal flow volume was decreased by 50% or more. The hyperechoic lesion was always larger than the area of pathological necrosis regardless of portal flow volume. Under conditions of decreased portal flow, the vessel endothelium near the ablated area was more readily damaged.
Decreased portal flow volume resulted in enlargement of the area of necrosis caused by RFA. Our results indicate that over-ablation could easily occur in patients with advanced cirrhosis, and that this could lead to major complications. Ultrasonographic guidance may be helpful for avoiding over-ablation.
背景/目的：尽管射频消融术（RFA）已被广泛认可为肝细胞癌（HCC）的有效治疗方法，但严重并发症并不罕见。主要并发症似乎是由于超出预期区域的过度消融所致。由于大多数HCC患者存在潜在的肝硬化，我们推测门静脉血流减少可能导致与RFA相关的坏死。为了证实这一假设，我们在猪模型中研究了在不同门静脉血流条件下RFA引起的坏死区域。
在麻醉的猪身上使用超声引导进行RFA。在RFA过程中，通过置于门静脉主干的球囊导管调节门静脉血流。处死动物后测量坏死区域，并与消融过程中出现的高回声区域进行比较。在另一次实验中，在肝静脉附近进行RFA并检查内皮损伤情况。
当门静脉血流量减少50%或更多时，RFA引起的坏死区域明显更大。无论门静脉血流量如何，高回声病变总是大于病理坏死区域。在门静脉血流减少的情况下，消融区域附近的血管内皮更容易受损。
门静脉血流量减少导致RFA引起的坏死区域扩大。我们的结果表明，晚期肝硬化患者很容易发生过度消融，这可能导致严重并发症。超声引导可能有助于避免过度消融。
