Inductively Heated Surgical Tool With Ferromagnetic Coating
Solution Overview
Problem
Current surgical tools, such as electrosurgery modalities and thermal devices, face issues like unintended tissue damage, slow heating and cooling, and the need for precise thermal control, particularly in achieving hemostasis and tissue destruction without causing collateral damage.
Innovation Solution
A thermal surgical tool system with a ferromagnetic coating over a conductor, powered by an oscillating electrical energy source for inductive heating, allowing for rapid and precise control of thermal effects, including hemostasis, tissue welding, and destruction, using a power control mechanism to adjust power delivery in real-time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If monopolar or bipolar electrosurgery modalities are used to achieve tissue cutting and coagulation, then hemostasis and tissue destruction can be achieved, but unintended tissue damage and deep tissue effects occur due to electrical current passing through the patient
Solution Approach 1:
The patent replaces electrical current-based heating (monopolar/bipolar electrosurgery) with resistive heating elements that convert electrical energy directly to heat at the tip of the instrument. This substitution confines thermal energy to the immediate treatment area, eliminating the need for current to pass through the patient's body and thereby preventing deep tissue effects and unintended damage while maintaining effective hemostasis and tissue destruction capabilities
Solution Approach 2:
The patent implements localized heating by concentrating thermal energy generation at the tip of the surgical instrument where treatment is needed. The resistive heating elements are positioned to generate heat only at the desired treatment site, creating a localized thermal field that affects only the target tissue and surrounding area, rather than causing widespread thermal damage to deep tissues
2Reliability
If high voltage is used in monopolar electrosurgery to achieve hemostasis, then coagulation effectiveness improves, but tissue damage extends away from the coagulation point and return electrode burns occur
Solution Approach 1:
The patent replaces high voltage electrical current with controlled resistive heating elements that generate thermal energy locally at the instrument tip. This substitution allows effective coagulation through controlled heating without requiring high voltage current to pass through the patient, thereby preventing both extended tissue damage and return electrode burns while maintaining coagulation effectiveness
Solution Approach 2:
The patent extracts the heating function from the electrical current path by using dedicated resistive heating elements at the instrument tip. This separation allows thermal energy to be generated exactly where needed without the harmful effects of electrical current passing through the patient's body, eliminating return electrode burns and limiting thermal damage to the immediate treatment area
3Speed
If ferrite beads and alloy mixes in ceramics are used for rapid heating, then heating speed improves, but material fracture occurs due to large temperature differential when contacted with liquids
Solution Approach 1:
The patent uses composite material structures for the resistive heating elements that combine materials with compatible thermal expansion coefficients and good thermal conductivity. This composite construction allows rapid heating while preventing material fracture when the heated element contacts body fluids, as the composite structure can accommodate thermal stresses without cracking or failing
Solution Approach 2:
The patent modifies the thermal and mechanical parameters of the heating element materials to achieve rapid heating without fracture. By selecting materials with appropriate thermal conductivity, heat capacity, and mechanical strength, the system achieves fast heating response while maintaining structural integrity when contacted with liquids at body temperature
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
Enables precise thermal control with rapid heating and cooling, minimizing accidental tissue damage and reducing the need for expensive equipment, while providing efficient tissue treatment with reduced deep tissue effects.
Implementation Method 1
an oscillating electrical energy source for generating heat at the location of the coating. The oscillating electrical energy may cause inductive heating of the ferromagnetic coating
Implementation Method 2
When excited by the magnetic field associated with high frequency current passing through a conductor, ferrite beads and alloy mixes in ceramics can reach high temperatures very quickly
Data Source
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AI summary
Oscillating electrical energy is delivered to an electrical conductor, such as a wire or a catheter, which is coated circumferentially with a ferromagnetic material in a selected region. With high frequency electrical energy, the ferromegnetic material has a quick response in heating and cooling adjustable by the controllable power delivery. The ferromagnetic material can be used for separating tissue, coagulation, tissue destruction or achieving other desired tissue effects in numerous surgical procedures. Thermal, electrosurgical and mechanical modalities may be combined in a surgical tool. Potentially damaging effects in a first modality may be minimized by using a secondary modality. In one example, thermal hemostatis may thus help electrosurgical applications avoid the adverse tissue effects associated with hemostatic monopolar electrosurgical waveforms while retaining the benefits of using monopolar incising waveforms.