McGahan J P, Gu W Z, Brock J M, Tesluk H, Jones C D
Department of Radiology, University of California Davis Medical Center, Sacramento 95817, USA.
Acad Radiol. 1996 May;3(5):418-22. doi: 10.1016/s1076-6332(05)80677-4.
Percutaneous methods have been used to treat primary and secondary hepatic neoplasms. In the current study, we evaluated the potential of bipolar radiofrequency (RF) electrocautery to increase in vitro liver tissue destruction when compared with monopolar RF electrocautery.
Two needles (electrodes) were placed into fresh bovine liver tissue for use with bipolar electrocautery. Needle tip exposure was kept constant at 3 cm while other parameters, including treatment time, power (wattage), interneedle distance, and needle tip temperature, were changed. Pathologic and histologic correlation was performed, and tissue necrosis was weighed in grams for individual parameters.
There was a minimal threshold of approximately 45 degrees C where tissue coagulation occurred. Tissue coagulation increased the longer treatment went on. Increasing temperature, wattage, or both increased tissue coagulation such that necrosis was too rapid and char formation occurred, which prevented further coagulation. For all wattages and temperatures, there was increasing tissue necrosis with increasing needle separation, until a point at which further needle separation produced less tissue necrosis. Optimizing parameters allowed tissue coagulation of greater than 30 g.
Bipolar RF electrocautery shows promise for increasing the tissue coagulation in fresh bovine liver compared with the previously described monopolar technique.
经皮方法已用于治疗原发性和继发性肝肿瘤。在本研究中，我们评估了双极射频（RF）电灼术与单极RF电灼术相比，在体外增加肝组织破坏的潜力。
将两根针（电极）插入新鲜牛肝组织中用于双极电灼术。针尖暴露长度保持在3 cm不变，同时改变其他参数，包括治疗时间、功率（瓦特数）、针间距和针尖温度。进行病理和组织学相关性分析，并对各个参数下的组织坏死重量以克为单位进行称重。
组织发生凝固时存在一个约45摄氏度的最小阈值。治疗持续时间越长，组织凝固越明显。温度升高、功率升高或两者同时升高都会增加组织凝固，导致坏死过快并形成焦痂，从而阻止进一步凝固。对于所有功率和温度，随着针间距增加，组织坏死增加，直到某一点，进一步增加针间距会导致组织坏死减少。优化参数可使组织凝固超过30克。
与先前描述的单极技术相比，双极RF电灼术在增加新鲜牛肝组织凝固方面显示出前景。
