## 2 Materials and Methods
### Experimental Ex Vivo Ablation Conditions  
The experimental set-up used for all the experiments is presented in Figure 1a. Figure 1b is a schematic representation of how the experimental set-up works. Bovine liver was used for the preliminary ex vivo ablative trials. Fresh beef liver was purchased from a local provider. All tissue samples for each set of experiments were cut from a single-animal liver in order to minimize variations in the dielectric properties of the various tissue samples. While this addresses the potential for inter-individual variations, it does not preclude that the placement of the ablation antenna may be affected by intra-tissue variations, such as the proximity of large empty blood vessels or fat pockets. These anatomical structures will be shown at the dissection step. During actual clinical procedures, these structures may be visualized and avoided using radiological imaging techniques such as ultrasound, computer tomography scanning, or magnetic resonance imaging. A commercial MW generator (SurBlate, Vison medical) was used for the preliminary evaluation of this novel MA-CA technology. Additionally, a commercially available cyst MW ablation probe (Vison Medical) was used as pre-beta prototype. The hollow lumens were used to dispense the chemical ablation agent into the target tissues simultaneously with the emission of the MW energy. The same antenna was used for each set of ablation conditions. After each experiment, ethanol was allowed to flow through the antenna at 5 mL/min to ensure that the channels were not clogged. Following this, the antenna was emptied of all residual ethanol using an air-filled syringe. The ablation procedures were performed using the conditions presented in Table 1. Various experiments were carried out at different durations and power levels, with and without ethanol. The optimum conditions obtained were the ones presented in Table 1. Additionally, 100 W was the typical practical value, and the other conditions were used to analyze, in the presence or absence of ethanol, the impact on the distribution of power in the irradiated zone. We also used simulation software (Ansys HFSS) and observed that the results obtained from the ex vivo samples were very similar to the results obtained with the simulation software. The modelling results showed, in the presence of ethanol, that the electric field was significantly concentrated around the emitter compared to the scenario without ethanol. All experiments were performed using the same total energy of 12,000 Joules. The first two sets of experiments, i.e., experimental conditions 1 and 2, were used to test the technology under MWA conditions, and no ethanol was added. Under experimental conditions 3 and 4, different sequences and different ethanol volumes were used. Experimental results where more power and less time were used gave better results. For the elution of ethanol, volume and flow rate were selected to control the spatial evolution of the electrical field and the resulting ablative process over time. The volume of ethanol dispensed was calculated as a function of its thermal properties to offer good control over thermal diffusion to the surrounding non-diseased tissue, and thus, reduce the potential for collateral damage. The effects of various parameters, including conventional ones such as power over time, were applied, along with MA-CA-specific ones such as volume of ethanol dispensed, and the ethanol elution rate was measured and monitored. The evolution of the temperature at various locations surrounding the emission point was monitored, as was the applied and reflected power over time as the ablation proceeded. The resulting ablation zones were  
Figure 1: (a) MA-CA experimental set up—real-time alcohol diffusion/ablation. Represented in the set up are: a data recorder, a microwave generator, an ablation antenna that is water cooled, thermocouples, fibre optics, and an HPLC pump to deliver the ethanol. (b) A schematic representation of the experimental set-up.