Digital Waveform Generator for Multi-Transducer Ultrasonic Surgery

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional ultrasonic and electrosurgical systems lack the ability to customize power output based on the type of tissue being treated, and they are limited in driving multiple ultrasonic transducers simultaneously or achieving various tissue effects with a single instrument.

Innovation Solution

A generator is designed with a digital processing circuit, memory circuit, and digital synthesis circuit to store and combine phase points from lookup tables, generating combined phase points that are converted into analog signals to drive multiple ultrasonic transducers, allowing for customizable electrical signal waveforms and simultaneous delivery of RF and ultrasonic energy.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional ultrasonic and electrosurgical systems are used, then the systems can perform basic cutting and coagulation functions, but they lack the ability to customize power output based on tissue type and cannot drive multiple ultrasonic transducers simultaneously

Engineering Contradiction:
Improvecustomizability of power outputVSAvoidsystem complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The generator is designed to drive multiple ultrasonic transducers (first and second transducers) simultaneously with different waveforms, enabling a single device to perform multiple surgical functions including cutting, coagulation, and hemostasis across different tissue types, thereby achieving multi-functionality and adaptability without requiring separate specialized devices

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Productivity

If a single ultrasonic transducer is used, then the system structure is simple, but it is impossible to achieve simultaneous cutting and coagulation with controlled power output for different tissue effects

Engineering Contradiction:
Improvesimultaneous tissue treatment capabilityVSAvoidnumber of transducers
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent combines multiple ultrasonic transducers (first and second transducers) into a single surgical instrument, allowing simultaneous generation of different ultrasonic waveforms for cutting and coagulation functions. This merging approach enables multiple tissue treatment capabilities while integrating the transducers within one unified device structure

Inventive Principle:
Principle #5Merging (Combining)

3Manufacturing precision

If conventional waveform generation is used, then the system is simple to operate, but it cannot achieve precise control of tissue effects for different tissue types

Engineering Contradiction:
Improveprecision of tissue effect controlVSAvoiddigital signal processing complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The system employs digital signal processing to generate and control multiple ultrasonic waveforms with varying parameters (frequency, amplitude, duty cycle) stored in lookup tables. By dynamically changing waveform parameters based on selected tissue types and desired effects, the system achieves precise control over tissue effects for cutting, coagulation, and hemostasis while maintaining programmable adaptability

Inventive Principle:
Principle #35Parameter changes

4Adaptability or versatility

If multiple waveforms are generated digitally with lookup tables, then customizable waveforms for different tissue types are achieved, but the device complexity increases

Engineering Contradiction:
Improvewaveform customization capabilityVSAvoiddigital processing circuit complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The system pre-calculates and stores multiple ultrasonic waveforms with different parameters in lookup tables within the digital processing circuit. This preliminary preparation of waveform data allows the system to quickly retrieve and switch between customized waveforms for different tissue types and surgical effects without performing complex real-time calculations, thereby achieving waveform adaptability while managing digital processing complexity through advance preparation

Inventive Principle:
Principle #10Preliminary action

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 control of tissue effects by generating customizable electrical signal waveforms, allowing for efficient cutting, coagulation, and hemostasis across different tissue types, while overcoming limitations of conventional systems in driving multiple ultrasonic transducers and achieving longer active lengths.

Implementation Method 1

a digital-to-analog converter (DAC) circuit... the DAC circuit to convert the combined phase point into an analog signal

Methodology Applied
Scientific EffectDigital-to-Analog Conversion:

Implementation Method 2

Vibrating at high frequencies (e.g., 55,500 times per second), the ultrasonic blade denatures protein in the tissue

Methodology Applied
Scientific EffectUltrasonic Vibration: Ultrasonic Vibration

Implementation Method 3

Heat generated by the current flowing through the tissue may form hemostatic seals within the tissue

Methodology Applied
Scientific EffectJoule Heating: Joule Heating

Data Source

PatentEP3355816B1Generator for digitally generating combined electrical signal waveforms for ultrasonic surgical instruments
Publication Date: 2022.06.15 ETHICON INC
  • EP3355816B1 patent drawingFigure 1
  • EP3355816B1 patent drawingFigure 2
  • EP3355816B1 patent drawingFigure 3

AI summary

Disclosed is a method of generating electrical signal waveforms by a generator. The method includes storing phase points of first and second digital electrical signal waveforms in first and second lookup tables. The first and second digital electrical signal waveforms are represented by a predetermined number of phase points that define wave shapes. At each clock cycle, a digital synthesis circuit retrieves phase points from the first and second lookup tables and the digital processing circuit combines phase points from the first and second lookup tables. A digital-to-analog converter (DAC) circuit converts the combined phase point into an analog signal. The analog signal is configured to drive a first and second ultrasonic transducer.