The Arthur Smith Institute for Urology, New Hyde Park, NY, USA.
BJU Int. 2012 Sep;110(5):688-91. doi: 10.1111/j.1464-410X.2012.10940.x. Epub 2012 Mar 6.
What's known on the subject? and What does the study add? With the advancement of minimally invasive surgery, the management of small renal masses (SRM) has dramatically changed. Ablative technology such as radiofrequency ablation (RFA) and cryoablation have emerged as viable alternative modalities to extirpative surgery. RFA is one of the most studied and applied energy-based, needle-ablative treatment modalities, with encouraging mid- and long-term oncological outcomes. Monopolar devices have several shortcomings. The electrodes are susceptible to the cooling effect of nearby blood vessels that act as a 'heat sink', limiting the extent of tissue ablation and forming lesions with asymmetric borders and 'skip lesions'. Therefore, it is difficult to monitor and accurately predict the size of ablated lesions. A novel bipolar radiofrequency ablation (BRFA) device has been recently developed to address concerns with monopolar systems (Trod Medical, Paris, France). The BRFA system addresses the limitations of monopolar RFA, in terms of lesion size, targeting, consistency and concerns about cell death in the ablated area. We evaluated the BRFA device in 10 patients undergoing laparoscopic partial or radical nephrectomy. The present study demonstrates the safety and efficacy of a novel BRFA device. A BRFA device can produce a defined reproducible lesion with a precise transition zone to normal tissue. The area of ablated tissue exhibited completely devitalized cells and precise transition zone. With these characteristics, the potential advantages of this new technology during RFA ablation of SRM include less collateral damage and more complete ablation without skip lesions. This has the potential to lower rates of local recurrence and reduce incidence of skin burns. Further follow-up studies are necessary to determine its oncological efficacy.
To evaluate a novel bipolar radiofrequency ablation (BRFA) system for the destruction of kidney tumours in patients.
Bipolar radiofrequency ablation (BRFA) was used to ablate renal masses in 10 patients undergoing laparoscopic radical or partial nephrectomy. The probe was placed percutaneously and laparoscopically guided into the tumour after routine laparoscopic exposure. The electrical current was continuously adjusted by the generator to overcome disruption from increasing impedance created from desiccated tissue. The specimens were then excised in routine fashion and analysed by a single pathologist. Lesion size and shape, and size of the transition zone to viable tissue were measured via nicotinamide adenine dinucleotide (NADH) staining.
Ablation was successful in all 10 tumours. Mean time to set up and place the probe was between 2 and 4 min. Duration of ablation was 200 s. None of the ablated tissue showed signs of viable cells by histological examination and NADH staining. The mean size of the ablation zone was 6.26 cm(3), with regular borders and a tapered cylindrical shape similar to the shape of the outer coil. The width of the transition zone, or area spanning complete tissue ablation to the first viable cells, ranged from 10 to 60 µm. There were no complications noted due to the ablation.
A BRFA device can produce a defined reproducible lesion with a precise transition zone to normal tissue. The area of ablated tissue exhibited completely devitalized cells and precise transition zone.
评估一种新型的双极射频消融（BRFA）系统在治疗肾肿瘤患者中的应用。
BRFA 用于消融 10 例行腹腔镜根治性或部分肾切除术患者的肾肿瘤。在常规腹腔镜暴露后，将探头经皮和腹腔镜引导至肿瘤部位。发生器不断调整电流，以克服由干燥组织引起的阻抗增加造成的干扰。然后按常规方法切除标本，并由一名病理学家进行分析。通过烟酰胺腺嘌呤二核苷酸（NADH）染色测量病变大小和形状以及与存活组织的过渡区大小。
10 个肿瘤的消融均获得成功。放置探头的平均设置和放置时间为 2 至 4 分钟。消融时间为 200 秒。组织学检查和 NADH 染色均未发现任何有活性细胞的消融组织。消融区的平均大小为 6.26cm3，边界规则，呈锥形圆柱形，与外管形状相似。过渡区的宽度，即跨越完全消融组织到第一个存活细胞的区域，范围为 10 至 60µm。由于消融没有出现并发症。
BRFA 设备可产生具有精确过渡区的规则可重复的病变。消融组织区域显示完全失活的细胞和精确的过渡区。
