Optimization of a single insertion electrode array for the creation of clinically relevant ablations using high-frequency irreversible electroporation

Abstract

High-frequency irreversible electroporation (H-FIRE) is an emerging ablation modality, delivering rapid bursts of bipolar microsecond-duration electrical pulses to non-thermally ablate tissue including tumors. With advantages over current electroporation techniques including mitigation of muscle stimulation and reduced susceptibility to heterogeneous tissue properties, H-FIRE may produce more uniform and predictable ablations and can potentially be delivered with a single applicator device. However, the resulting ablations tend to be smaller than those provided with equivalent energy monopolar pulse protocols. Here, we develop numerical simulations that demonstrate the potential for clinically relevant ablations with H-FIRE delivered via a single insertion technique comprised of an expandable array and a distally placed grounding pad. Based on existing in vivo data and new in vitro results, delivery of H-FIRE with a clinical IRE single electrode probe (1 cm long) is predicted to produce a 2.2 cm3 ablation while an optimized eight tine array produces a 3.2 cm3 ablation when the same H-FIRE bursts are delivered (5000 V). We demonstrate that alternative pulse protocols can be used to increase ablation volumes with this optimized array and these results indicate that in vivo investigation of a single insertion array and grounding pad are warranted.