Optimization and characterization of a novel internally-cooled radiofrequency ablation system with optimized pulsing algorithm in an bovine liver.

To prospectively characterize and optimize radiofrequency energy deposition to determine ideal parameters for achieving large ablation zones. An internally-cooled RF system was used to perform 214 ablations in 72 bovine livers. Tip exposure (1-5 cm), electrode current (400-2500 mA), and application duration (3-15 min) were systematically varied.

Evaluation of a CT-Guided Robotic System for Precise Percutaneous Needle Insertion.

Purpose: To assess overall targeting accuracy for CT-guided needle insertion using prototype robotic system for common target sites.

Materials And Methods: Using CT guidance, metallic (2 × 1 mm) targets were embedded in retroperitoneum (n = 8), kidneys (n = 8), and liver (n = 14) of 8 Yorkshire pigs (55-65 kg). Bronchial bifurcations were targeted in the lung (n = 13).

Optimizing Irreversible Electroporation Ablation with a Bipolar Electrode.

Purpose: To optimize single-insertion bipolar irreversible electroporation (IRE) by characterizing effects of electric parameters and controlling tissue electric properties in a porcine model.

Materials And Methods: Single-insertion electrode bipolar IRE was performed in 28 in vivo pig livers (78 ablations). First, effects of voltage (2,700-3,000 V), number of pulses, repeated cycles (1-6 cycles), and pulse width (70-100 µs) were studied.

Irreversible electroporation: treatment effect is susceptible to local environment and tissue properties.

Purpose: To study the effects of the surrounding electrical microenvironment and local tissue parameters on the electrical parameters and outcome of irreversible electroporation (IRE) ablation in porcine muscle, kidney, and liver tissue.

Materials And Methods: Animal Care and Use Committee approval was obtained, and National Institutes of Health guidelines were followed. IRE ablation (n = 90) was applied in muscle (n = 44), kidney (n = 28), and liver (n = 18) tissue in 18 pigs.

Irreversible electroporation ablation: is all the damage nonthermal?

Purpose: To determine whether high-dose irreversible electroporation (IRE) ablation induces thermal effects in normal liver tissue.

Materials And Methods: Animal care and use committee approval was obtained prior to the experiments. IRE ablation (n = 78) was performed by a single four-person team in vivo in 22 porcine livers by applying electric current to two 1.

Characterization of irreversible electroporation ablation in in vivo porcine liver.

Objective: The purpose of this study was to prospectively characterize and optimize irreversible electroporation ablation to determine the best parameters to achieve the largest target zones of coagulation for two electrodes.

Materials And Methods: Ultrasound-guided irreversible electroporation ablation (n=110) was performed in vivo in 25 pig livers using two 18-gauge electroporation electrodes and an irreversible electroporation generator. Five variables for energy deposition and electrode configuration were sequentially studied: number of electrical pulses (n=20-90), length of pulses (20-100 microseconds), generator voltage (2250-3000 V), interelectrode spacing (1.