Microwave Ablation Probe Crimped Choke for RF Reflection Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Microwave ablation probes face challenges in minimizing tissue damage and creating a repeatable, known heating zone due to back current reflections, which can cause undesirable heating and damage to surrounding tissues, and existing solutions increase the probe size, exacerbating the issue.
Innovation Solution
The integration of a crimped choke within the microwave ablation probe's inner tube, which blocks back current reflections and a cooling system to circulate fluid, maintains a small probe size while controlling the ablation zone's shape and size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the microwave ablation antenna size is reduced to minimize damage to surrounding tissue, then the damage to non-target tissue is minimized, but the ability to produce a repeatable and known heating zone becomes compromised
Solution Approach 1:
A choke structure is introduced as an intermediary component between the antenna and the surrounding tissue. The choke acts as a mediator that controls the electromagnetic field distribution, enabling the antenna to produce a predictable and repeatable heating zone while maintaining a small size. The choke's specific impedance characteristics mediate the interaction between the antenna and tissue, ensuring controlled energy delivery.
Solution Approach 2:
The choke structure changes the electrical parameters (impedance, current distribution) in the region surrounding the antenna. By modifying these parameters through the choke's design, the heating zone characteristics become more predictable and repeatable, even with a small antenna size. The choke transforms the electromagnetic field parameters to achieve desired thermal outcomes.
2Object-affected harmful factors
If a choke structure is added to block back current reflections, then the damage to surrounding tissue is reduced, but the device complexity increases
Solution Approach 1:
The choke structure is merged with the existing probe components, integrating the back current blocking function into the overall probe design rather than adding a completely separate component. The choke is positioned and configured to work in conjunction with the antenna and cooling system, combining multiple functions into a unified structure that reduces overall complexity.
Solution Approach 2:
The choke is implemented as a thin-walled tubular structure that is flexible in its electromagnetic interaction while maintaining structural integrity. This thin-film approach allows the choke to perform its function of blocking back currents without requiring bulky or complex construction, keeping the overall device compact and simple.
3Manufacturing precision
If the inner tube is crimped to form a choke, then the manufacturing precision is improved, but the ease of manufacture decreases
Solution Approach 1:
The crimping operation is performed at a predetermined position along the inner tube, establishing the choke location before final assembly. This preliminary action ensures precise positioning of the choke relative to the antenna and cooling channels, achieving the required manufacturing precision while allowing the crimping process to be standardized and simplified.
Solution Approach 2:
The crimping process replaces more complex mechanical positioning or assembly operations. By using a simple crimping action to form the choke, the manufacturing process becomes easier while still achieving precise positioning. The crimping mechanism substitutes for more elaborate fixation or alignment systems that would otherwise be required.
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 crimped choke effectively reduces back current reflections, allowing for a more spherical and controlled ablation zone, minimizing damage to non-target tissues and maintaining a compact probe size, thereby improving the precision and safety of microwave ablation treatments.
Implementation Method 1
The inward formation can block back current that may be reflected from the antenna of the probe during operation
Implementation Method 2
a cooling system to circulate fluid
Implementation Method 3
A microwave ablation antenna can be included in the probe and be used to deliver Radio Frequency (RF) energy such as microwave energy to a target tissue to heat the target tissue and destroy the target tissue
Data Source
AI summary
A microwave ablation probe includes a cable comprising an antenna configured to deliver Radio Frequency (RF) energy to a target zone and a cooling path defined by a first channel and a second channel configured to circulate cooling fluid in the probe. The inner tube also comprises a choke formed thereon configured to reduce RF energy reflected away from the antenna.