Production of Large Ellipsoidal Ablations Using Integrated Nanosecond Pulse Irreversible Electroporation Administered...

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 in vivo liver model.

A percutaneous approach to the liver was made under ultrasound (US) guidance in female pigs weighing between 25 and 35 kg. Protocols consisting of 500-, 1,000-, or 2,000-nanosecond waveforms, 45 °C or 65 °C temperature set point, and 0.02-second dose were administered at 6,000 V with and without active applicator cooling.

INSPIRE temperature control algorithms successfully achieved and maintained target temperatures in vivo. All treatments were completed successfully without cardiac synchronization. Treatments with active cooling and temperature control were completed in approximately 4-8 minutes. Treatment zone sizes ranged from 5.7 to 17.3 cm³ with longer pulse widths resulting in larger volumes. Protocols with 2,000-nanosecond pulses resulted in the largest treatment zones measuring 3.8 cm × 2.4 cm.

INSPIRE treatments can be safely administered through a single applicator approach with voltages up to 6,000 V without prior knowledge of tissue electrical properties or local tissue perfusion conditions. The single applicator method markedly simplifies electroporation procedures compared with conventional multiapplicator methods by generating an ellipsoidal treatment zone.