目的比较水冷915MHz和2450MHz微波在活体与离体猪肝实验中温度曲线和消融区的差异。方法使用915和2450MHz微波消融和热监测系统,共获得58个消融区和180个温度数据。输出设置为915MHz50W,70W和2450MHz50W,70W,并设置时间为600S。每个温度点的温度曲线在天线旁开5、10、15mm处,对消融区的宽径和长径进行测量。结果在活体与离体实验中,除旁开5mm,915MHz水冷微波其余点的峰值温度[活体50w10mm:(59+4.26)℃;70W10mm:(67±9.01)℃]均高于2450MHz微波[活体50w10mm:(54±4.09)℃;70w10mm:(57±6.13)℃](P〈0.05)。在相同条件下,离体肝脏的消融区宽径和长径[活体50w宽径:(3.13±0.76)cm;长径(4.95±0.87)cm]均显着大于2450MHz微波[活体50w宽径:(2.34±0.49)cm;长径(3.43±0.96)cm](P〈0.05)。结论在离体和活体的肝脏实验中,915MHz水冷微波比2450MHz可以形成更大的消融区和达到更高的温度。
Objective To compare temperature curve and ablation zone between 915 and 2450 MHz cooled-shaft microwave antenna for porcine livers in vivo and in vitro. Methods The 915 and 2450 MHz microwave ablation and thermal monitor system were used in this study. A total of 58 ablation zones and 180 temperature data were obtained from porcine livers in vivo and in vitro. The output settings were 915 MHz 50 W, 70 W and 2450 MHz 50 W , 70 W, and the setting time was 600 s. The temperature curve of every temperature spot was at 5, 10, 15 mm away from the antenna, and the short- and long-axis diameters of the coagulation zones were measured. Results The peak temperatures for the 915 MHz cooled-shaft antenna[in vivo 50 W 10 mm: (59±4.26)℃ ; 70 W 10 mm: (67±9.01)℃ ] were significantly higher than those for the 2450 MHz cooled-shaft antenna [in vivo 50 W 10 mm: (54±4.09)℃;70 W 10 mm: (57±6.13)℃ ] in both in vitro and in vivo livers except for 5 mm away from the antenna in vitro liver(P〈0.05). Meanwhile, the short- and long-axis diameters for the 915 MHz cooled-shaft antenna[in vivo 50 W short axis: (3.13_+0.76)em; long-axis (4.95±0.87)cm I were significantly larger than those for the 2450 MHz cooled-shaft antenna [ in vivo 50 W short- axis: (2.34±0.49) cm;long-axis (3.43±0.96) cm in both in vitro and in vivo porcine livers (P〈 0.05). At the same setting, the short- and long-axis diameters in the in vitro liver increased compared to those in vivo liver, and in 70 W power setting, the peak temperature of every surveying spot in the in vitro liver wassignificantly higher than that in tile in vivo liver (P〈0.05). Conclusion The 915 MHz cooled-shaft antenna can yiehl a significantly larger ablation zone and achieve higher temperature in ablation zone than a 2450 MHz cooled-shaft antenna in both in vitro and in vivo livers.