Targeted Tissue Ablation With Nanosecond Pulses

Ethicon Endo-Surg., Cincinnati, OH, USA
IEEE Transactions on Biomedical Engineering (Impact Factor: 2.35). 09/2011; 58(8):2161 - 2167. DOI: 10.1109/TBME.2011.2113183
Source: IEEE Xplore


In-vivo porcine studies on the effect of nanosecond high-voltage pulses on liver tissue have shown that cell death can be induced in well-defined tissue volumes without damaging collagen-predominant structures. Comparison of the experimental results with the results of a 3-D finite element model allowed us to determine the threshold electric field for cell death. For 30, 100-ns-long pulses this was found to be in the range from 12 to 15 kV/cm. Modeling of the temperature distribution in the tissue using Pennes' bioheat equation showed that the lethal effect of nanosecond pulses on cells is nonthermal. Muscle contractions, generally caused by high-voltage pulses, were significantly reduced for the 100-ns pulses compared to microsecond-long pulses. The results of these studies indicate that high-voltage nanosecond pulses reliably kill normal liver cells in vivo, and therefore, may be useful for liver tumor treatments.

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Available from: Stephen Beebe, Dec 18, 2015
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    • "The high voltage pulses were delivered to the centre needle [33] [34]. The tumour is surrounded by the electrode array thereby establishing a well-define treatment zone minimising damage to surrounding tissue [22]. The margins of safety are determined by tumour size and electrode design. "
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    • "Confining the treatment only to cancer cells may be obtained by placing the electrodes in the cancerous tissue and in the meantime creating a large electric field gradient from cancerous tissue to normal tissue using needle electrodes. As a result, a relatively well-defined ablation zone may be expected [37]. The correlation of electric field intensity and cell death become a priori in order to define the effective treatment zone and spare normal tissue. "
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