Figure 4From: Analytical and numerical quantification and comparison of the local electric field in the tissue for different electrode configurations Calculated electric field distribution for different needle electrode configurations. Numerical results of the electric field distribution for the geometries defined in Fig. 2: a) two needle electrodes, b) four needle electrodes, c) six needle electrodes in two rows, d) six electrodes placed in a circle with polarities as shown in Fig. 2d, e) six needle electrodes placed in a circle with polarities as shown in Fig. 2e, f) seven needle electrodes placed in a circle – using alternating polarities seven needle electrodes placed in a circle – with central positive and surrounding electrodes having negative polarities and g) seven needle electrodes placed in a circle – with central positive and surrounding electrodes having negative polarities. In all cases the applied voltage was set in such a way that U/d = 1.15 V/cm, where d = 8.66 mm for Figs. 4a, 4b, 4c, 4d and 4e and d = 5 mm for Figs. 4f and 4g. The circle represents the target tissue and the white region represents part of tissue where E ≥ U/d.Back to article page