Non-Symmetric RF Pulse Waveform for Safe Tissue Electroporation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods of irreversible electroporation for tissue destruction, such as high voltage pulses, pose a risk of electrical shock and tissue damage due to high amplitude and duration requirements, which are not effectively mitigated by current techniques.
Innovation Solution
The use of non-symmetrical radio-frequency (RF) pulses with alternating polarities, where one half-wave has high amplitude and short duration and the other has low amplitude and longer duration, balances voltage to minimize electrical shocking effects while achieving electroporation, combined with pre-heating or cooling to reduce treatment thresholds.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high voltage pulses with high amplitude and long duration are used for irreversible electroporation, then electroporation effect is improved, but risk of electrical shock and tissue damage increases
Solution Approach 1:
The electrical pulse is segmented into multiple sub-pulses within each half-cycle. Instead of applying a single high-voltage pulse, the patent divides the pulse into several smaller pulses (e.g., 5-10 sub-pulses) that collectively achieve the required electroporation effect. This segmentation reduces the voltage amplitude of individual pulses, thereby reducing electrical shock risk while maintaining cumulative electroporation effectiveness.
Solution Approach 2:
The patent employs periodic alternating polarity pulses where positive and negative half-cycles are repeated in sequence. Each half-cycle contains multiple sub-pulses, and the alternating polarity creates a periodic action that prevents DC shock while achieving cumulative electroporation. The periodic reversal of polarity ensures that no single continuous high-voltage pulse can cause electrical shock, yet the repeated exposure to electrical fields achieves effective cell membrane disruption.
2Ease of operation
If pulse duration is reduced below 10 microseconds to reduce electrical shock sensation, then patient comfort is improved, but higher amplitude of HV pulses is required which increases electrical shock risk
Solution Approach 1:
The patent segments the pulse duration by applying multiple short sub-pulses within each half-cycle. Instead of using a single long high-voltage pulse, the total pulse duration is divided into multiple shorter sub-pulses (e.g., 1-5 microseconds each). This allows the overall treatment duration to be extended for effective electroporation while each individual sub-pulse remains short enough to minimize patient discomfort and electrical shock sensation.
Solution Approach 2:
The patent applies multiple partial pulses (sub-pulses) that individually provide less than the full electroporation effect, but their cumulative action achieves the required therapeutic effect. By applying 5-10 sub-pulses per half-cycle, the patent achieves excessive total exposure that ensures effective electroporation while keeping each individual pulse amplitude and duration within safe limits.
3Reliability
If multiple high voltage pulses are applied to achieve consistent electroporation, then treatment effectiveness is improved, but risk of electrical shock and tissue damage increases
Solution Approach 1:
The patent segments each electrical pulse into multiple sub-pulses with reduced amplitude. Instead of applying a single high-voltage pulse that could cause tissue damage, the pulse is divided into 5-10 smaller sub-pulses. This segmentation allows multiple pulses to be applied for consistent electroporation while the reduced amplitude of each sub-pulse minimizes the risk of arcing, skin surface damage, and electrical shock.
Solution Approach 2:
The patent uses periodic alternating polarity pulses where the rhythm of positive and negative half-cycles creates a safe repeating pattern. The periodic nature allows controlled application of multiple pulses while the polarity reversal prevents cumulative DC effects. This periodic action enables consistent electroporation through repeated exposure while maintaining safety through the alternating pattern that prevents sustained high-voltage shock.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach allows for effective tissue destruction with reduced risk of electrical shock, enabling efficient cell apoptosis with lower electric field strengths, suitable for cosmetic and medical procedures like body contouring and tumor treatment, while maintaining safety and minimizing tissue damage.
Implementation Method 1
This method is based on changing cell membranes using high electrical field leading to the apoptotic death of cells
Implementation Method 2
the high density electrical current flowing through the tissue creates Joule heat increasing tissue temperature to the necrotic level
Implementation Method 3
radio-frequency (RF) energy is used to create thermal tissue destruction. At frequencies above 100 kHz the electrical current does not affect the nerves significantly
Data Source
AI summary
A method for soft tissue destruction comprises applying high voltage pulses causing irreversible electroporation alternating with low amplitude pulses of opposite polarity balanced to provide negligible average current and minimize risk of electrical shock. The method may be accompanied by tissue heating to reduce the electroporation threshold and negative pressure for skin shaping and optimal voltage distribution.