Ablation Waveform Generator for Muscle-Sparing Biphasic Pulses

The single monophasic pulse is segmented into multiple phase components (first phase with first polarity, second phase with second polarity, third phase with first polarity) delivered in sequence. This segmentation allows the waveform to accumulate sufficient charge for effective IRE while interspersing opposite polarity phases that prevent muscle stimulation by canceling out depolarization effects.

The waveform employs periodic alternation between opposite polarities within each pulse cycle. The first phase (first polarity) is followed by a second phase (second polarity), then a third phase (first polarity), creating a periodic structure that delivers cumulative ablation effect while periodically neutralizing muscle stimulation through polarity reversal.

The waveform parameters are changed from a simple biphasic structure to a multiphasic structure with three distinct phases. The first phase delivers the primary ablation charge, the second phase (with opposite polarity and potentially different duration/amplitude) prevents muscle stimulation, and the third phase (returning to first polarity) supplements the ablation effect. This parameter transformation maintains charge balance for muscle safety while accumulating sufficient total charge for effective IRE.

The waveform is constructed as a composite of multiple phase components with different characteristics. Each phase contributes differently to the overall effect: the first phase provides initial poration, the second phase provides charge balance and muscle protection, and the third phase provides additional poration. This composite structure achieves both safety and efficacy that neither simple monophasic nor simple biphasic waveforms can achieve alone.

The periodic alternation between opposite polarity phases prevents sustained current flow in one direction that would generate heat through resistive heating. By rapidly switching polarities within the pulse train, the waveform delivers cumulative electroporation effects while the alternating directions cancel out thermal accumulation, allowing higher effective doses without thermal damage risk.

The potential harmful effect of high power delivery is converted into a benefit through the multiphasic structure. The opposite polarity phases, which could be seen as reducing net charge delivery, actually prevent thermal accumulation by reversing current direction before significant heat can build up. This transforms what would be a thermal hazard into a safety feature that enables higher effective dosing.