Experiments of Microwave Ablation Based on Dual-Frequency Antenna Under Pulsed Mode

In this letter, we review the microwave ablation (MWA) under pulsed wave (PW) mode and perform the experiments by using a dual-frequency antenna. Parameters such as frequency (915 MHz or 2450 MHz), excitation power (40 W or 60 W), duty cycle (40%–60%), cycle (10 ms–100 s), and durations (5 min or 10) min are variably combined in different experimental schemes for investigation. Based on the results of these experiments, which use our super compact dual-frequency antenna and egg white as a reference tissue environment, it can be seen that PW MWA may reduce backward heating and increase ablation roundness to 0.964 (compared to a traditional continuous wave (CW) ablation roundness of 0.5). For further verification of these results and for comparison, a single-frequency antenna is also used under PW mode and the achieved ablation roundness is 0.91, which is also greater than that of 0.55 under CW mode. PW MWA can thus be considered as an effective candidate for tissue ablation during the treatment of tumors.