Plasma-Based Tissue Ablation via Capacitive Coupling

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing electrosurgical devices for tissue ablation face challenges such as slow treatment times, incomplete treatments, non-uniform ablation depths, and risk of injury to adjacent organs due to inefficiencies in delivering radiofrequency energy.

Innovation Solution

The use of a system that delivers radiofrequency current through a series of dielectric media, where an electrically non-conductive gas is ionized to form a plasma, capacitively coupling the energy to tissue through a thin dielectric wall, allowing for controlled and uniform ablation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If traditional solid electrodes or balloon electrodes are used for radiofrequency ablation, then tissue ablation can be achieved, but treatment times are relatively slow and ablation depths are non-uniform

Engineering Contradiction:

Improvetreatment speedVSAvoidablation depth uniformity

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The patent changes the physical state of the dielectric medium from liquid or solid to gas, and utilizes ionization to transform the gas into plasma. This parameter change enables rapid energy transfer to tissue while the ionized state provides uniform current distribution across the electrode surface, achieving both fast treatment and uniform ablation depth

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent replaces traditional direct contact mechanical electrodes with a capacitive coupling system using ionized gas plasma. This substitution eliminates the need for direct mechanical contact between solid electrodes and tissue, allowing for more uniform energy distribution and faster treatment while maintaining precise control over ablation depth

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If high power radiofrequency energy is delivered to achieve complete ablation, then treatment completeness improves, but risk of injury to adjacent organs increases

Engineering Contradiction:

Improveablation completenessVSAvoidrisk of injury to adjacent organs

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent introduces ionized gas plasma as an intermediary medium between the electrode and the target tissue. This plasma layer acts as a controlled energy transfer interface that distributes radiofrequency energy uniformly, ensuring complete ablation of the target while preventing excessive energy concentration that could damage adjacent organs

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

By changing the dielectric medium to ionized gas plasma, the patent achieves better control over energy penetration depth and distribution. The plasma state allows for precise adjustment of energy parameters, enabling complete ablation of the target tissue while limiting energy spread to protect surrounding healthy tissues and organs

Inventive Principle:

Principle #35Parameter changes

3Use of energy by moving object

If radiofrequency current is delivered through direct contact electrodes, then energy transfer is efficient, but treatment uniformity and control are compromised

Engineering Contradiction:

Improveenergy transfer efficiencyVSAvoidablation uniformity

Core Design Contradiction:

Use of energy by moving objectVSManufacturing precision

Solution Approach 1:

The patent replaces direct mechanical contact between electrodes and tissue with capacitive coupling through ionized gas plasma. This substitution maintains high energy transfer efficiency by utilizing the conductive properties of plasma while achieving uniform current distribution across the entire electrode surface, thereby improving both efficiency and uniformity simultaneously

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 enables rapid, uniform tissue ablation with controlled depth and reduced risk to adjacent organs by effectively coupling radiofrequency energy through a plasma formed in an electrically non-conductive gas, improving treatment efficiency and safety.

Implementation Method 1

an electrically non-conductive gas which is ionized to capacitively couple to surrounding tissue

Methodology Applied

Scientific EffectIonization: Ionisation

Implementation Method 2

the gas is ionized to form a plasma, typically by application of a high voltage radiofrequency voltage

Methodology Applied

Scientific EffectPlasma formation: Plasma

Implementation Method 3

capacitively couple the current in the plasma across the dielectric wall and into tissue adjacent the external surface

Methodology Applied

Scientific EffectCapacitive coupling: Capacitance

Implementation Method 4

delivering a radiofrequency current to the tissue in order to heat and usually ablate the tissue

Methodology Applied

Scientific EffectRadiofrequency heating: Dielectric Heating

Data Source

PatentUS8197476B2Tissue ablation systems

Publication Date: 2012.06.12 AXORA MEDICAL INC

AI summary

Tissue is treated using a radiofrequency power supply connected to an applicator having a chamber filled with an electrically non-conductive gas surrounded by a thin dielectric wall. A radiofrequency voltage is applied at a level sufficient to ionize the gas into a plasma and to capacitively couple the ionized plasma with the tissue to deliver radiofrequency current to ablate or otherwise treat the tissue.