Tan Beng Jit, El-Hakim Assaad, Morgenstern Nora, Semerdzhiev Yavor, Smith Arthur, Lee Benjamin R
Department of Urology, Long Island Jewish Medical Center, New Hyde Park, New York 11040-1496, USA.
J Urol. 2004 Nov;172(5 Pt 1):2007-12. doi: 10.1097/01.ju.0000138083.84066.98.
We investigated and compared the gross and histopathological features of radio frequency (RF) ablated renal tissue using saline infused RF ablation (RFA) vs dry RFA in a porcine model.
Ten porcine kidneys underwent laparoscopic RFA. The lower and upper poles of each right kidney were treated with 1 and 2 cycles of saline augmented (wet) RFA, respectively. The upper pole of each left kidney was RF ablated without saline infusion (dry RFA) and a control lesion was created in the lower pole. The animals were sacrificed immediately after ', 2 and 9 days after (subacute), and 14 and 21 days after (chronic) treatment, respectively. Gross pathological and histological changes caused by the different RF treatments were compared.
Mean time to attain target temperature was shorter with wet than with dry RFA. Grossly the lesion sizes achieved were larger using wet RFA but independent of the number of wet RFA treatment cycles. Gross lesion sizes decreased with time for each treatment modality. No histopathological differences were seen between the 2 RFA treatment modalities as well as between 1 vs 2 cycles of wet RFA. In the acute phase hematoxylin and eosin staining of ablated tissue revealed focal areas of alterations in renal tubular histology. However, nicotinamide adenine dinucleotide staining of corresponding areas confirmed the lack of cellular viability except for glomeruli. In the subacute phase there were focal coagulation necrosis and thrombosed blood vessels. Within the necrotic areas the glomeruli were the last structures to lose viability. In the chronic phase fibrosis with decreased lesion size was seen. Nicotinamide adenine dinucleotide staining demonstrated that the cellular kill was permanent during the entire study period.
The effects of RFA of renal tissue has 2 phases, namely initial direct thermal ablation causing acute cell death and a later subacute phase causing subsequent infarction of the distal arterial vascular supply to the ablated region, resulting in more cell death and coagulative necrosis. Glomeruli are the last structures to lose viability in necrotic areas. Most importantly cellular death caused by RFA is permanent.
我们在猪模型中研究并比较了使用生理盐水灌注射频消融（RFA）与干式RFA对射频消融肾组织的大体和组织病理学特征。
十只猪肾接受了腹腔镜RFA。每个右肾的下极和上极分别用1个和2个周期的生理盐水增强（湿式）RFA进行治疗。每个左肾的上极在不灌注生理盐水的情况下进行射频消融（干式RFA），并在下极创建一个对照病变。动物分别在治疗后即刻、2天和9天（亚急性期）以及14天和21天（慢性期）后处死。比较不同射频治疗引起的大体病理和组织学变化。
湿式RFA达到目标温度的平均时间比干式RFA短。大体上，湿式RFA实现的病变大小更大，但与湿式RFA治疗周期数无关。每种治疗方式的大体病变大小随时间减小。两种RFA治疗方式之间以及湿式RFA的1个周期与2个周期之间均未观察到组织病理学差异。在急性期，消融组织的苏木精-伊红染色显示肾小管组织学有局灶性改变区域。然而，相应区域的烟酰胺腺嘌呤二核苷酸染色证实除肾小球外缺乏细胞活力。在亚急性期有局灶性凝固性坏死和血栓形成的血管。在坏死区域内，肾小球是最后失去活力的结构。在慢性期可见纤维化且病变大小减小。烟酰胺腺嘌呤二核苷酸染色表明在整个研究期间细胞杀伤是永久性的。
肾组织RFA的作用有两个阶段，即最初直接热消融导致急性细胞死亡，随后是亚急性期导致消融区域远端动脉血管供应的后续梗死，导致更多细胞死亡和凝固性坏死。肾小球是坏死区域最后失去活力的结构。最重要的是，RFA引起的细胞死亡是永久性的。
