Lee J M, Han J K, Chang J M, Chung S Y, Kim S H, Lee J Y, Choi B I
Department of Radiology, and Institute of Radiation Medicine, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul 110-744.
Br J Radiol. 2006 Jul;79(943):562-71. doi: 10.1259/bjr/51844219.
The purpose of this study was to compare the amounts of in vivo coagulation obtained by radiofrequency (RF) ablation in porcine lung, using three types of electrodes. 15 in vivo ablation procedures were performed in the lungs of five pigs using three kinds of currently available RF devices under CT guidance. After placing an electrode in the lung, three ablation zones were created at each of three different regimens: Group A: RF ablation with an internally cooled electrode; Group B: RF ablation with a perfusion electrode, with instillation of 0.9% NaCl solution at a rate of 1.5 ml min(-1); Group C: RF ablation with a multitined expandable electrode. According to the manufacturer's recommendations, RF application times were 12 min in group A and 20 min in group B. In group C, RF energy was delivered for 7 min after a mean temperature of 110 degrees C was reached at 5 cm deployment. 36 min after the procedures, contrast-enhanced CT scans were obtained to evaluate the volume of zone of coagulation, and lungs were harvested for gross measurements. After macroscopic and histopathological analyses of 5 mm-thick lung sections, diameters, volumes and variation coefficients of regions of central coagulation were assessed. During RF ablation, the perfusion electrode allowed a larger energy delivery than the internally cooled or the multitined expandable electrodes, i.e. 33.6+/-4.7 kJ in group A, 40.0+/-8.2 kJ in group B and 23.5+/-6.1 kJ in group C (p<0.05). On gross observation, the cut surface of the gross specimen containing RF-induced coagulation showed that the ablated tissue appeared to be a central, firm, dark-brown area surrounded by an irregular outer margin (approximately 3-10 mm thick) of bright red tissue. In vivo studies showed that RF ablation using the perfusion electrode achieved larger coagulation volume than RF ablation using the other electrodes (p<0.05): 7.2+/-4.1 cm3 in group A; 16.9+/-5.5 cm3 in group B; 7.5+/-3.3 cm3 in group C. The corresponding variation coefficients were 0.55, 0.31, and 0.45, respectively. Our study shows that RF ablation using a perfusion electrode achieves a larger coagulation volume with an irregular margin than RF ablation using internally cooled or multitined expandable electrodes in the porcine lung.
本研究的目的是比较使用三种类型电极在猪肺中通过射频（RF）消融获得的体内凝血量。在CT引导下，使用三种现有的RF设备对五头猪的肺部进行了15次体内消融手术。将电极置于肺内后，在三种不同方案下各创建三个消融区：A组：使用内部冷却电极进行RF消融；B组：使用灌注电极进行RF消融，以1.5 ml min(-1)的速率滴注0.9%氯化钠溶液；C组：使用多叉可扩张电极进行RF消融。根据制造商的建议，A组的RF施加时间为12分钟，B组为20分钟。在C组中，在5 cm展开时达到110℃的平均温度后，施加RF能量7分钟。手术后36分钟，进行对比增强CT扫描以评估凝血区的体积，并摘取肺进行大体测量。对5 mm厚的肺切片进行宏观和组织病理学分析后，评估中央凝血区域的直径、体积和变异系数。在RF消融过程中，灌注电极比内部冷却电极或多叉可扩张电极允许传递更大的能量，即A组为33.6±4.7 kJ，B组为40.0±8.2 kJ，C组为23.5±6.1 kJ（p<0.05）。大体观察显示，含有RF诱导凝血的大体标本的切面表明，消融组织似乎是一个中央坚实的深棕色区域，周围是一层不规则的鲜红色组织外缘（约3-10 mm厚）。体内研究表明，使用灌注电极进行RF消融比使用其他电极获得的凝血体积更大（p<0.05）：A组为7.2±4.1 cm3；B组为16.9±5.5 cm3；C组为7.5±3.3 cm3。相应的变异系数分别为0.55、0.31和0.45。我们的研究表明，在猪肺中，使用灌注电极进行RF消融比使用内部冷却电极或多叉可扩张电极获得的凝血体积更大，边缘不规则。
