Ultrasonic Surgical Instrument Frequency Dithering for Resonance Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ultrasonic surgical instruments lack effective frequency control mechanisms to maintain optimal energy transfer efficiency and tissue treatment outcomes, particularly in varying tissue loads and temperatures.
Innovation Solution
An ultrasonic surgical system with a controller that adjusts the frequency of the ultrasonic drive signal based on mechanical motion feedback, using a test signal to calculate resonant frequency and maintain or adjust the frequency range around the resonant frequency to achieve desired tissue treatment outcomes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the ultrasonic drive signal frequency is fixed, then the device complexity is reduced, but the energy transfer efficiency decreases in varying tissue loads and temperatures
Solution Approach 1:
The patent implements dynamic frequency adjustment by continuously monitoring the resonant frequency of the ultrasonic transducer and modifying the drive signal frequency accordingly. This allows the system to adapt to varying tissue loads and temperatures, maintaining optimal energy transfer efficiency without requiring complex manual intervention.
Solution Approach 2:
The patent employs a feedback mechanism where a sensor detects the actual resonant frequency of the ultrasonic transducer, and the controller adjusts the drive signal frequency based on this feedback. This closed-loop control ensures that the system automatically maintains optimal operating conditions despite changes in tissue properties.
2Adaptability or versatility
If the frequency range is widened to accommodate tissue variations, then the adaptability improves, but the manufacturing precision of the transducer decreases
Solution Approach 1:
The patent changes the operating frequency parameter dynamically rather than relying on fixed manufacturing precision. By adjusting the drive signal frequency within a controlled range around the resonant frequency, the system can adapt to different tissue loads while the transducer itself maintains its designed resonant characteristics.
Solution Approach 2:
The patent applies partial frequency adjustment rather than complete frequency variation. By limiting the frequency range to a controlled deviation from the resonant frequency, the system achieves sufficient adaptability for tissue variations while preserving the manufacturing precision benefits of operating near the transducer's designed resonant point.
3Productivity
If the ultrasonic power is increased to improve productivity, then the transection speed increases, but the tissue damage increases
Solution Approach 1:
The patent dynamically adjusts the ultrasonic power level based on real-time detection of tissue conditions and transducer resonant frequency. This allows the system to optimize power delivery for each specific tissue type and loading condition, achieving high productivity while minimizing unnecessary tissue damage from excessive power.
Solution Approach 2:
The patent changes the power parameter of the ultrasonic drive signal based on detected tissue properties and resonant frequency conditions. By modulating power levels within an optimized range rather than operating at maximum power, the system maintains high transection speed while reducing harmful thermal effects on tissue.
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
Enhances energy transfer efficiency and maintains consistent tissue treatment results by dynamically controlling the frequency of the ultrasonic drive signal, ensuring optimal blade velocity and temperature for sealing or transecting tissue.
Implementation Method 1
ultrasonic surgical instruments and systems utilize mechanical vibration energy transmitted at ultrasonic frequencies to treat tissue
Implementation Method 2
an ultrasonic transducer electrically coupled to the ultrasonic generator to receive the ultrasonic drive signal therefrom and configured, in response to the received ultrasonic drive signal, to produce a mechanical motion
Implementation Method 3
Ultrasonic energy transmitted to the blade causes the blade to vibrate at very high frequencies, which allows for heating tissue to treat tissue clamped against or otherwise in contact with the blade
Implementation Method 4
a sensor configured to sense a frequency and a magnitude of the mechanical motion, and a controller configured to receive a target mechanical motion to be produced by the ultrasonic transducer and control the ultrasonic drive signal
Implementation Method 5
controlling the ultrasonic drive signal so that a frequency of the ultrasonic drive signal falls within a frequency range around a resonant frequency of the ultrasonic transducer, the frequency range corresponding to the target mechanical motion produced by the ultrasonic transducer
Data Source
AI summary
An ultrasonic surgical system includes an ultrasonic generator configured to provide an ultrasonic drive signal, and an ultrasonic transducer electrically coupled to the ultrasonic generator to receive the ultrasonic drive signal therefrom and configured, in response to the received ultrasonic drive signal, to produce a mechanical motion. The ultrasonic surgical system further includes a sensor configured to sense a frequency and a magnitude of the mechanical motion, and a controller configured to receive a target mechanical motion to be produced by the ultrasonic transducer and control the ultrasonic drive signal so that a frequency of the ultrasonic drive signal falls within a frequency range around a resonant frequency of the ultrasonic transducer, the frequency range corresponding to the target mechanical motion produced by the ultrasonic transducer.