Novel tetrapolar single-needle electrode for electrochemotherapy in bone cavities: Modeling, design and validation.

Electrochemotherapy is a cancer treatment in which local pulsed electric fields are delivered through electrodes. The effectiveness of the treatment depends on exposing the tumor to a threshold electric field. Electrode geometry plays an important role in the resulting electric field distribution, especially in hard-to-reach areas and deep-seated tumors. We designed and developed a novel tetrapolar single-needle electrode for proper treatment in bone cavities. In silico and in vitro experiments were performed to evaluate the electric field and electric current produced by the electrode. In addition, tomography images of a real case of nasal cavity tumor were segmented into a 3D simulation to evaluate the electrode performance in a bone cavity. The proposed electrode was validated and its operating range was set up to 650 V. In the nasal cavity tumor, we found that the electrode can produce a circular electric field of 3 mm with an electric current of 14.1 A at 500 V, which is compatible with electrochemotherapy standards and commercial equipment.