Impact of Voltage on the Production on Spherical Ablations for Integrated Time Nanosecond Pulse Irreversible Electroporation.

Abstract

Objective: To study the safety and reproducibility of high-voltage integrated nanosecond pulse irreversible electroporation (INSPIRE) administered through a single applicator and grounding pad approach in a healthy liver model.

Methods: A percutaneous approach to the liver was made under ultrasound guidance in female pigs weighing between 25 and 35 kg. INSPIRE treatments at 3000 V, 4500 V, and 6000 V using 1000 ns or 2000 ns waveforms, with a 0.02 s dose and a 45°C temperature set point were delivered using an actively cooled single applicator and distal grounding pad. Ablation size, muscle stimulation, and cardiac safety were evaluated.

Results: All INSPIRE treatments were completed successfully without cardiac synchronization or break-through muscle stimulation. Ablations were visible on ultrasound shortly after treatments were complete. Treatments were completed within approximately 2-8 minutes. The largest ablations, achieved with the 2000 ns waveform at 6000 V, measured 4.4 ± 0.7 cm by 2.9 ± 0.1 cm.

Conclusion: INSPIRE can be safely used to achieve significantly larger ablations significantly faster than current irreversible electroporation (IRE) technologies using a simplified single-applicator and grounding pad approach.

Significance: INSPIRE overcomes technical and procedural challenges facing IRE including ablation size limitations, muscle stimulation, the need for cardiac synchronization, long procedure times, and the lack of visualization during procedures.