Abstract
Background and Purpose:
Radiofrequency (RF) ablation of renal tumors is a major technique for tumor cell destruction while preserving healthy renal parenchyma. There is no consensus in the literature regarding the optimal temperature, impedance, and time for RF application for effective cell destruction. This study investigated two variables while keeping time unchanged: Temperature for RF cell destruction and tissue impedance in dog kidneys.
Materials and Methods:
Sixteen dogs had renal punctures through videolaparoscopy for RF interstitial tissue ablation. A RF generator was applied for 10 minutes to the dog's kidney at different target temperatures: 80°C, 90°C, and 100°C. On postoperative day14, the animals were sacrificed and nephrectomized. All lesions were macroscopically and microscopically examined. The bioelectrical impedance was evaluated at three different temperatures.
Results:
Renal injuries were wider and deeper at 90°C (P < 0.001), and they were similar at 80°C and 100°C. The bioelectrical impedance was lower at 90°C than at the temperatures of 80°C and 100°C (P < 0.001). Viable cells in the RF ablation tissue area were not found in the microscopic examination.
Conclusion:
The most effective cell destruction in terms of width and depth was achieved at 90°C, which was also the optimal temperature for tissue impedance. RF ablation of renal cells eliminated all viable cells.