Ultrasonic End Effector Feedback for Tissue Sealing With Less Heat
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current ultrasonic surgical instruments face challenges in effectively sealing blood vessels and providing feedback to users about tissue cutting, leading to potential damage from excessive heat generation and limited ability to recognize instrument configurations for optimized control.
Innovation Solution
The development of a surgical system that includes a method for driving an ultrasonic end effector with a generator capable of monitoring electrical signals and determining tissue impedance, providing feedback through visual, audible, and tactile indicators, and using frequency step functions to separate and seal tissue layers without relying solely on clamp force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If ultrasonic energy is applied to cut and seal tissue, then cutting precision and hemostasis are improved, but heat generation causes potential damage to surrounding tissue
Solution Approach 1:
The ultrasonic blade operates by vibrating at high frequency (e.g., 55,500 times per second) in periodic cycles, creating mechanical cutting action through cavitation and mechanical stress rather than continuous heat application. This periodic vibration allows precise tissue separation while limiting thermal damage to adjacent structures.
Solution Approach 2:
The ultrasonic energy causes phase transitions in tissue proteins through denaturation, transforming the tissue structure from its native state to a coagulated state. This phase change mechanism enables cutting and sealing through protein coagulation rather than thermal carbonization, reducing harmful heat effects on surrounding tissue.
2Reliability
If clamp force is increased to separate vessel layers for sealing, then vessel sealing efficiency is improved, but device complexity and operational difficulty increase
Solution Approach 1:
Instead of relying solely on increased mechanical clamp force to separate vessel layers, the ultrasonic blade uses high-frequency mechanical vibration to mechanically separate the inner muscle layer from the adventitia layer. This vibration-based separation mechanism achieves effective vessel layer separation without requiring excessively complex clamp force mechanisms.
Solution Approach 2:
The patent replaces purely mechanical clamp force application with ultrasonic vibration-based tissue separation. The ultrasonic energy field substitutes for excessive mechanical pressure, achieving layer separation through acoustic-mechanical interaction rather than solely through mechanical force, thereby reducing device complexity.
3Manufacturing precision
If ultrasonic power is continuously applied to ensure complete cutting, then cutting completeness is improved, but energy consumption increases and risk of instrument damage rises
Solution Approach 1:
The system incorporates feedback mechanisms that monitor cutting progress and tissue impedance changes in real-time. Based on this feedback, the ultrasonic power delivery is dynamically adjusted to provide only the necessary energy for complete cutting, preventing excessive energy consumption and reducing the risk of instrument damage from prolonged high-power operation.
Solution Approach 2:
The ultrasonic blade applies partial action by using high-frequency low-amplitude vibrations rather than continuous high-power delivery. This approach achieves complete cutting through cumulative mechanical effect over time, reducing instantaneous energy consumption and minimizing the risk of instrument overheating or damage while ensuring cutting completeness.
4Loss of information
If visual feedback is provided to indicate cut completion, then user awareness is improved, but device complexity increases
Solution Approach 1:
The system employs color changes or visual indicators (such as LED indicators or display color changes) to communicate cut completion status to the user. This visual feedback mechanism provides clear information about cutting progress without requiring complex sensor arrays or processing systems, maintaining simplicity while improving user awareness.
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 solution enhances vessel sealing efficiency, reduces heat-related damage, and allows for optimized control of ultrasonic surgical instruments by providing real-time feedback and adaptive frequency adjustments, improving hemostasis and reducing energy consumption.
Implementation Method 1
Vibrating at high frequencies (e.g., 55,500 times per second), the ultrasonic blade denatures protein in the tissue
Implementation Method 2
the ultrasonic blade denatures protein in the tissue to form a sticky coagulum
Implementation Method 3
A generator is coupled to an ultrasonic drive system... capable of monitoring electrical signals and determining tissue impedance
Data Source
AI summary
Various embodiments are directed to a method of driving an end effector coupled to an ultrasonic drive system of a surgical instrument. The method comprises generating at least one electrical signal. The at least one electrical signal is monitored against a first set of logic conditions. A first response is triggered when the first set of logic conditions is met. A parameter is determined from the at least one electrical signal.