Segmented RF Ablation Needle for Spherical Tumor Treatment

Solution Overview

Problem

Radiofrequency ablation (RFA) therapy is inefficient due to rising tissue impedance and temperature, requiring temporary cessation of treatment, and existing electrode needles produce ellipsoid ablation shapes that damage surrounding normal tissue when treating sphere-like liver tumors.

Innovation Solution

A monopolar radiofrequency ablation electrode needle with distinct impedance segments, where one segment with lower impedance is interposed between higher impedance segments, allowing for controlled ablation and adjustable exposure to achieve a sphere-like ablation shape, reducing unnecessary tissue damage and treatment time.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single needle electrode is used for radiofrequency ablation, then the treatment can be performed with a simple device structure, but the ablation shape becomes ellipsoid-like which causes unnecessary damage to normal tissue surrounding sphere-like liver tumors

Engineering Contradiction:

Improveelectrode needle structureVSAvoiddamage to normal tissue

Core Design Contradiction:

Device complexityVSObject-affected harmful factors

Solution Approach 1:

The electrode needle is divided into multiple segments with different impedance characteristics (first segment with lower impedance, second segment with higher impedance). This segmentation allows different portions of the needle to contribute differently to the ablation field, enabling more precise control over the ablation shape to match sphere-like tumors while reducing damage to surrounding normal tissue.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different segments of the electrode needle are assigned different impedance properties (first segment: lower impedance, second segment: higher impedance) to create localized variations in the electric field distribution. This local quality differentiation enables the ablation zone to conform more accurately to the spherical tumor shape rather than producing a uniform ellipsoid shape.

Inventive Principle:

Principle #3Local quality

2Productivity

If radiofrequency ablation is performed continuously, then treatment efficiency is maximized, but tissue impedance rises and temperature increases requiring temporary cessation of treatment

Engineering Contradiction:

Improvetreatment efficiencyVSAvoidtreatment continuity

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The electrode needle is divided into multiple segments with different impedance characteristics (first segment with lower impedance, second segment with higher impedance). This segmentation allows different portions of the needle to contribute differently to the ablation field, enabling more precise control over the ablation shape to match sphere-like tumors while reducing damage to surrounding normal tissue.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different segments of the electrode needle are assigned different impedance properties (first segment: lower impedance, second segment: higher impedance) to create localized variations in the electric field distribution. This local quality differentiation enables the ablation zone to conform more accurately to the spherical tumor shape rather than producing a uniform ellipsoid shape.

Inventive Principle:

Principle #3Local quality

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

The electrode needle enables more efficient tissue ablation with reduced treatment time and minimizes normal tissue damage by maintaining lower impedance levels, achieving a sphere-like ablation shape that meets clinical needs for treating sphere-like liver tumors.

Implementation Method 1

The electrode needle will release radio frequency waves, and the tissue which the radio frequency waves pass through will generate thermal energy due to ion agitation, so that the temperature of the treatment area starts to rise.

Methodology Applied

Scientific EffectIon agitation: Joule Heating

Data Source

PatentUS10888372B2Radiofrequency ablation electrode needle

Publication Date: 2021.01.12 IND TECH RES INST

AI summary

A radiofrequency ablation electrode needle includes at least one first segment and at least two second segments. The at least one first segment and the at least two second segments are exposed on a surface of the needle body. An impedance of the at least one first segment is smaller than an impedance of the at least two second segments and at least one of the at least one first segment is disposed between two immediately adjacent ones of the at least two second segments. Besides, the radiofrequency ablation electrode needle is a monopolar electrode needle.