Feng Jian, Wang Song, Jiang Kai
Department of Hepatobiliary Surgery, Chinese PLA General Hospital, Beijing 100853, China.
Department of General Surgery, Taizhou Central Hospital (Taizhou University Hospital), Taizhou 318000, Zhejiang Province, China.
World J Gastrointest Oncol. 2021 Feb 15;13(2):109-118. doi: 10.4251/wjgo.v13.i2.109.
The results of the heat irrigating effect of radiofrequency ablation (RFA) are uncertain, and the accurate impact of the heat irrigating effect on regional liver tissue is unknown due to a lack of control experiments.
The aim of this study was to determine the influence of the heat irrigating effect of RFA on regional liver tissue in Bama miniature pigs.
Eight Bama miniature pigs were randomly divided into the observation group (group A) and the control group (group B), with 4 pigs/group. An RFA electrode needle was implanted near the hepatic segment vasculature (3-5 mm from the hepatic segment portal vein) under ultrasound guidance in group A. Similarly, an RFA electrode needle was implanted far from the hepatic segment vasculature (8-10 mm from the hepatic segment portal vein) in group B. The left internal lobe and right medial lobe were chosen as RFA sites in each pig. RFA was performed at the left internal lobe on day one in each pig, and at the right medial lobe 7 d later. Each RFA lasted 12 min. The general status of the pigs and serious complications were observed during the perioperative period. The pigs were sacrificed and the livers were removed immediately after RFA on the eighth day. The samples were roughly observed. Hematoxylin-eosin and Ki67 staining, as well as TUNEL detection, were performed on the tissue sections.
All 8 animals successfully underwent ultrasound-guided RFA. No serious complications, such as massive hemorrhage, biliary fistula, severe pleural effusion, pneumothorax, peripheral organ failure, or renal failure occurred in any of the animals during the perioperative period. The RFA coagulative necrosis lesion was spherical and the surrounding liver tissue showed an inflammatory response. The difference in the Suzuki score of the liver tissue surrounding the ablated portal vein, and its distal area between groups A and B, was statistically significant ( < 0.05). More apoptotic cells were seen in liver tissue surrounding the ablated portal vein and its distal area in group A, while fewer apoptotic cells in the same area were seen in group B. The difference in the apoptotic index of the above area between group A and group B was statistically significant ( < 0.05). Cells staining positive for Ki67 were observed in liver tissue at the left internal lobe around the ablated portal vein and its distal area in group A. No Ki67 staining positive cells were observed in other tissue sections. The difference in the Ki67 staining positive index in the above area was statistically significant ( < 0.05) between group A and group B.
Changes as a result of thermal damage occur in liver tissue around the ablated portal vein and its distal area due to the heat irrigating effect when the RFA electrode tip is close to (< 5 mm) the portal vein.
射频消融（RFA）热灌注效应的结果尚不确定，由于缺乏对照实验，热灌注效应对局部肝组织的准确影响尚不清楚。
本研究旨在确定RFA热灌注效应对巴马小型猪局部肝组织的影响。
将8只巴马小型猪随机分为观察组（A组）和对照组（B组），每组4只。A组在超声引导下将RFA电极针植入肝段血管附近（距肝段门静脉3 - 5 mm）。同样，B组将RFA电极针植入远离肝段血管处（距肝段门静脉8 - 10 mm）。每只猪选择左内叶和右中叶作为RFA部位。每只猪第1天在左内叶进行RFA，7 d后在右中叶进行RFA。每次RFA持续12 min。观察围手术期猪的一般情况及严重并发症。第8天RFA后立即处死猪并取出肝脏。对样本进行大体观察。对组织切片进行苏木精-伊红染色、Ki67染色以及TUNEL检测。
8只动物均成功接受超声引导下的RFA。围手术期所有动物均未发生严重并发症，如大量出血、胆瘘、严重胸腔积液、气胸、外周器官衰竭或肾衰竭。RFA凝固性坏死灶呈球形，周围肝组织出现炎症反应。A组和B组消融门静脉周围及其远端区域肝组织的铃木评分差异有统计学意义（<0.05）。A组消融门静脉周围及其远端区域肝组织可见更多凋亡细胞，而B组同一区域凋亡细胞较少。A组和B组上述区域凋亡指数差异有统计学意义（<0.05）。A组消融门静脉周围及其远端区域左内叶肝组织中观察到Ki67染色阳性细胞。其他组织切片未观察到Ki67染色阳性细胞。A组和B组上述区域Ki67染色阳性指数差异有统计学意义（<0.05）。
当RFA电极尖端靠近（<5 mm）门静脉时，由于热灌注效应，消融门静脉周围及其远端区域的肝组织会发生热损伤改变。
