Figures & data
Figure 1. (A) Experimental set-up; (B) Experimental set-up, electric wiring scheme: ○ electrode; • thermocouple.
Figure 2. (A) Measurement of the ablation zone size, definition of planes. (B) Measurements in the axial plane: - - - - rectangle defined by the active parts of the electrodes; – – – – coagulation zone; small arrows, axial margins outside this rectangle; large arrow, axial diameter. (C) Measurements in the transverse plane: ···· square defined by the active parts of the electrodes; – – – coagulation zone; small arrows, lateral margins outside this square; large arrows, transverse diameters.
Figure 3. Geometrical model for FEM analysis.
Table I. Thermal and electrical properties of liver and electrode Citation[22].
Figure 4. (A) Influence of the inter-electrode distance on temperature as measured during experiments or predicted by FEM. (B) Influence of the inter-electrode distance on completeness of ablation in both planes.
Figure 5. Influence of the inter-electrode distance on the coagulation zone in the axial and transverse planes.
Table II. Dimensions of the coagulation zone with standard set-up: Experimentally measured (mean ± SD (range)) vs. predicted by FEM.
Figure 6. Evolution of impedance and temperature with the standard set-up: 50 W power, 2 cm inter-electrode distance, 1.8 mm diameter electrodes (mean ± SD).
Figure 7. (A) Electric field in the transverse plane at the mid height of the electrodes applying 50 W with an inter-electrode distance of 3 cm. (B) Temperature (°C) after 7 min of RFA in the transverse plane applying 50 W with an inter-electrode distance of 3 cm. ––– 50° isotherm; - - - - 60° isotherm.
Figure 8. (A) 3D representation of 50°C isotherm after 7 min of RFA applying 50 W with an inter-electrode distance of 2 cm (left: front view; right: side view). (B) 3D representation of 50°C isotherm after 7 min of RFA applying 50 W with an inter-electrode distance of 3 cm (left: front view; right: side view).
