Feasibility of 3D quality assurance system with electrode array for electric fields therapy

In this study, we investigated the feasibility of a three-dimensional quality assurance system for Tumor-Treating Fields (TTFields) therapy by applying voltage to a water phantom using an electrode array. The water phantom was prepared by mixing deionized (DI) water with NaCl. A voltage of 50 V_pp at 150 kHz was applied to the phantom, and voltage measurements were taken along five profiles by moving the probe within the phantom to minimize electric field distortion. The experimental data were analyzed using error rates and gamma index analysis. In the three-dimensional evaluation, the average differences in voltage and electric field were 1.06% and 6.65%, respectively. The gamma passing rates for voltage, using criteria of 5%/3 mm and 3%/3 mm, were 100% and 99.61%, respectively. For the electric field, the gamma passing rates were 93.63% and 88.31% when evaluated using criteria of 10%/5 mm and 5%/5 mm, respectively. These findings suggest that employing three-dimensional quality assurance with the electrode array can significantly enhance the treatment quality of TTFields therapy.