[go: up one dir, main page]

WO2025083577A1 - Système électrochirurgical et procédé de vérification de la précision d'un capteur de courant - Google Patents

Système électrochirurgical et procédé de vérification de la précision d'un capteur de courant Download PDF

Info

Publication number
WO2025083577A1
WO2025083577A1 PCT/IB2024/060145 IB2024060145W WO2025083577A1 WO 2025083577 A1 WO2025083577 A1 WO 2025083577A1 IB 2024060145 W IB2024060145 W IB 2024060145W WO 2025083577 A1 WO2025083577 A1 WO 2025083577A1
Authority
WO
WIPO (PCT)
Prior art keywords
test signal
sensor
processor
signal parameter
inverter
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
PCT/IB2024/060145
Other languages
English (en)
Inventor
Lewis R. PUTERBAUGH
Mark A. Johnston
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Covidien LP
Original Assignee
Covidien LP
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Covidien LP filed Critical Covidien LP
Publication of WO2025083577A1 publication Critical patent/WO2025083577A1/fr
Pending legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B18/04—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by heating
    • A61B18/12—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body by heating by passing a current through the tissue to be heated, e.g. high-frequency current
    • A61B18/1206—Generators therefor
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00642—Sensing and controlling the application of energy with feedback, i.e. closed loop control
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00696—Controlled or regulated parameters
    • A61B2018/00702—Power or energy
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00696—Controlled or regulated parameters
    • A61B2018/00702—Power or energy
    • A61B2018/00708—Power or energy switching the power on or off
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00773—Sensed parameters
    • A61B2018/00827—Current
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00773—Sensed parameters
    • A61B2018/00869—Phase
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00773—Sensed parameters
    • A61B2018/00892—Voltage
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B18/00—Surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body
    • A61B2018/00636—Sensing and controlling the application of energy
    • A61B2018/00898—Alarms or notifications created in response to an abnormal condition
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass

Definitions

  • Electrosurgery involves application of high radio frequency (RF) electrical current to a surgical site to cut, ablate, desiccate, or coagulate tissue.
  • RF radio frequency
  • a source or active electrode delivers radio frequency alternating current from the electrosurgical generator to the targeted tissue.
  • a patient return electrode is placed remotely from the active electrode to conduct the current back to the generator.
  • bipolar electrosurgery In bipolar electrosurgery, return and active electrodes are placed in close proximity to each other such that an electrical circuit is formed between the two electrodes (e.g., in the case of an electrosurgical forceps). In this manner, the applied electrical current is limited to the body tissue positioned between the electrodes. Accordingly, bipolar electrosurgery generally involves the use of instruments where it is desired to achieve a focused delivery of electrosurgical energy between two electrodes. Some electrosurgical generators use a closed loop control scheme for setting RF energy output to the instrument and include RF sensors for feedback control.
  • the present disclosure provides for electrosurgical generators including one or more sensors for measuring electrical properties of output RF energy.
  • the sensors are part of a closed loop control scheme where the sensor measurements are used to control the generator’s energy output. Accordingly, a closed-loop system’s performance is affected by the accuracy of sensor output, and inaccuracy in the measurements provided by the sensors may result in erroneous RF output.
  • One approach for verifying accuracy of the sensors is to use redundant sensor chains. The outputs of two redundant sensor chains can be compared and if the sensors’ measurements differ sufficiently, a dosage error signal can be output. However, this approach requires use of redundant sensor chains that are sufficiently similar to each other, which is costly. The presently disclosed systems and methods can verify acceptable RF sensor operation without using such redundant sensor chains.
  • the electrosurgical generator includes a stimulation circuit for injecting a test signal through an additional primary winding of a sensor to verify the current sensor chain is within specifications at any suitable time, e.g., at start up, prior to each activation, or some other frequency.
  • the circuit injects a square wave signal with known current into a current sensor, such as a current transformer or a Rogowski coil. By using a square wave at or near the RF output frequency, the sensor can be checked at the three main frequencies of interest. This circuit eliminates the need for a redundant RF sensor chain and saves space and cost of the generator design.
  • an electrosurgical generator includes a radio frequency (RF) inverter for outputting an RF waveform and a sensor coupled to the RF inverter for measuring one or more parameters of the RF waveform.
  • the generator also includes a stimulation circuit coupled to the sensor for outputting a test signal through the sensor and a processor for receiving a measured test signal from the sensor, comparing a measured test signal parameter to a stored test signal parameter, determining an operational status of the sensor based on a comparison of the measured test signal parameter to the stored test signal parameter, and controlling the RF inverter based on the operational status of the sensor.
  • RF radio frequency
  • the generator may also include an isolation transformer coupled to the RF inverter via a conductor.
  • the sensor may be a current sensor and may have a first winding galvanically coupled to the conductor.
  • the electrosurgical generator may further include a sensing circuit for providing RF current sensor measurements to the processor.
  • the current sensor may further include a second winding galvanically coupled to the sensing circuit.
  • the current sensor may additionally include a third winding galvanically coupled to the stimulation circuit.
  • the second winding may be magnetically coupled to (i.e., galvanically isolated from) the first winding and the third winding.
  • the processor may further process the measured test signal using a Goertzel algorithm to determine the measured test signal parameter.
  • the measured test signal may be a square waveform and the measured test signal parameter may be at least one of amplitude or phase.
  • the square waveform may have the same fundamental frequency as the RF waveform.
  • the processor may further process the measured test signal at a plurality of harmonic frequencies of the square waveform.
  • the processor may also determine whether the sensor is faulty based on a mismatch between the measured test signal parameter and the stored test signal parameter.
  • the electrosurgical generator may also include a display, and the processor may further output an alert on the display in response to determining the sensor is faulty.
  • a method for verifying accuracy of a sensor in an electrosurgical generator includes receiving a measured test signal from a sensor coupled to an RF inverter outputting an RF waveform, and a stimulation circuit providing a test signal to the sensor.
  • the method also includes comparing, at a processor, a measured test signal parameter to a stored test signal parameter and determining, at the processor, an operational status of the sensor based on a comparison of the measured test signal parameter to the stored test signal parameter.
  • the method further includes controlling, via the processor, the RF inverter based on the operational status of the sensor.
  • Implementations of the above embodiment may include one or more of the following features.
  • the method may also include processing the measured test signal using a Goertzel algorithm to determine the measured test signal parameter.
  • the measured test signal may be a square waveform and the measured test signal parameter is at least one of amplitude or phase.
  • the square waveform may have the same fundamental frequency as the RF waveform.
  • the method may further include processing the measured test signal at a plurality of harmonic frequencies of the square waveform.
  • the method may additionally include determining, at the processor, whether the sensor is faulty based on a mismatch between the measured test signal parameter and the stored test signal parameter.
  • the method may also include outputting an alert on a display of the electrosurgical generator in response to determining the sensor is faulty.
  • an electrosurgical generator includes a radio frequency (RF) inverter for outputting an RF waveform.
  • the generator also includes an isolation transformer coupled to the RF inverter via a conductor and a stimulation circuit for outputting a test signal.
  • the generator also includes a sensor coupled to the RF inverter for measuring at least one parameter of the RF waveform.
  • the sensor also includes a first winding galvanically coupled to the conductor, a second winding galvanically coupled to a sensing circuit, and a third winding galvanically coupled to the stimulation circuit.
  • the generator further includes a processor for receiving a measured test signal from the sensor, comparing a measured test signal parameter to a stored test signal parameter, determining an operational status of the sensor based on a comparison of the measured test signal parameter to a stored test signal parameter, and controlling the RF inverter based on the operational status of the sensor.
  • FIG. 1 is a perspective view of an electrosurgical system according to an embodiment of the present disclosure
  • FIG. 2 is a front view of an electrosurgical generator of FIG. 1 according to an embodiment of the present disclosure
  • FIG. 3 is a schematic diagram of the electrosurgical generator of FIG. 1 according to an embodiment of the present disclosure
  • FIG. 5 is a flow chart of a method for verifying accuracy of the current sensor according to an embodiment of the present disclosure.
  • an electrosurgical generator may be used in monopolar and/or bipolar electrosurgical procedures, including, but not limited to, cutting, coagulation, ablation, vessel sealing procedures, etc.
  • the generator may include a plurality of outputs for interfacing with various ultrasonic and electrosurgical instruments (e.g., ultrasonic dissectors and hemostats, monopolar instruments, return electrode pads, bipolar electrosurgical forceps, footswitches, etc.). Further, the generator may include electronic circuitry configured to generate radio frequency energy specifically suited for powering ultrasonic instruments and electrosurgical devices operating in various electrosurgical modes (e.g., cut, blend, coagulate, division with hemostasis, fulgurate, spray, etc.) and procedures (e.g., monopolar, bipolar, vessel sealing).
  • ultrasonic and electrosurgical instruments e.g., ultrasonic dissectors and hemostats, monopolar instruments, return electrode pads, bipolar electrosurgical forceps, footswitches, etc.
  • the generator may include electronic circuitry configured to generate radio frequency energy specifically suited for powering ultrasonic instruments and electrosurgical devices operating in various electrosurgical modes (e.g., cut, blend, coagulate, division with hemostasis, ful
  • an electrosurgical system 10 which includes one or more monopolar electrosurgical instruments 20 (also referred to herein as “monopolar instrument 20”) having an active electrode 23 (e.g., electrosurgical cutting probe, ablation electrode(s), etc.) for treating tissue of a patient.
  • the system 10 may include a plurality of return electrode pads 26 that, in use, are disposed on a patient to minimize the chances of tissue damage by maximizing the overall contact area with the patient.
  • Electrosurgical alternating RF current is supplied to the monopolar instrument 20 by a generator 100 via supply line 24. The alternating RF current is returned to the generator 100 through the return electrode pad 26 via a return line 28.
  • the generator 100 and the return electrode pads 26 may be configured for monitoring tissue-to- patient contact to ensure that sufficient contact exists therebetween.
  • the return electrode pad 26 includes a pair of flat, flexible (e.g., foil) electrodes 26a and 26b, which are used to monitor tissue-to-patient contact by detecting a difference in electrical properties of the foil electrodes 26a and 26b.
  • the electrosurgical system 10 also includes one or more bipolar electrosurgical instruments 30 (also referred to herein as “bipolar instrument 30”) having one or more electrodes for treating tissue of a patient.
  • bipolar instrument 30 Two non-limiting examples of bipolar instruments 30 are shown as an electrosurgical sealing device 51 and electrosurgical tweezers 52.
  • the electrosurgical sealing device 51 30 includes a housing 31 and opposing jaw members 33 and 35 disposed at a distal end of a shaft 32.
  • the jaw members 33 and 35 have one or more active electrodes 34 and a return electrode 36 disposed therein, respectively.
  • the active electrode 34 and the return electrode 36 are connected to the generator 100 through cable 38 that includes the supply and return lines 24’, 28’, which may be coupled to active and return terminals 210 and 212, respectively, of the generator 100 (FIG. 3).
  • the electrosurgical sealing device 51 is coupled to the generator 100 at a port having connections to the active and return terminals 210 and 212 (FIG. 3) via a plug disposed at the end of the cable 38, wherein the plug includes contacts from the supply and return lines 24’, 28’ as described in more detail below.
  • the electrosurgical sealing device 51 also includes a button 42 configured to signal to the generator 100 to output electrosurgical energy through the electrodes 34 and 36.
  • the electrosurgical sealing device 51 also includes a lever 40 movable relative to a handle 41.
  • the handle 41 is formed as part of the housing 31 and the lever 40 may be pivotably coupled within the housing 31.
  • the lever 40 actuates, i.e., opens and closes, the jaw members 33 and 35, via one or more mechanical linkages
  • the electrosurgical tweezers 52 include a pair of electrodes 53a and 53b, respectively, for treating tissue of a patient.
  • the electrosurgical tweezers 52 are coupled to a generator 100 via a cable 58 having supply and return lines 56 and 57, respectively.
  • the electrosurgical system 10 also includes a footswitch 70, which may be a pedal.
  • the footswitch 70 may be paired to activate any one of the monopolar instrument 20, the electrosurgical sealing device 51 , or the electrosurgical tweezers 52, and may provide an alternative activation mechanism in addition to the user inputs on the generator 100 or any hand switches present on the aforementioned instruments.
  • the footswitch 70 may include a plurality of buttons and/or switches configured to provide multiple user inputs.
  • the generator 100 may include a plurality of ports 110, 112, 114, 116 to accommodate various types of electrosurgical instruments, a port 118 for coupling to a return electrode pad, and a port 119 configured to couple to the footswitch 70. While illustrated on the front face 102, it will be understood that the ports 110, 112, 114, 116, 118, 119 can be positioned at any suitable location on the generator 100, including a top surface, a back surface, a bottom surface, or the like.
  • the ports 110 and 112 are configured to couple to monopolar electrosurgical instruments (e.g., the monopolar instrument 20).
  • the ports 114 and 116 are configured to couple to bipolar electrosurgical instruments (e.g., the bipolar instruments 30).
  • the generator 100 includes a display 120 for providing the user with variety of output information (e.g., intensity settings, treatment complete indicators, etc.).
  • the display 120 is a touchscreen configured to display a menu for each of the ports 110, 112, 114, 116 and the coupled instrument. The user may also adjust inputs by touching corresponding menu options.
  • the generator 100 may further include suitable input controls 122 (e.g., buttons, activators, switches, touch screen, etc.) for controlling the generator 100.
  • the generator 100 operates in a variety of modes, in which the generator 100 outputs monopolar and/or bipolar waveforms corresponding to the selected mode.
  • Each of the modes may be activated by the button 42 disposed on the electrosurgical sealing device 30.
  • Each of the modes outputs RF energy based on a preprogrammed power curve that limits how much power is output by the generator 100 at varying impedance ranges of the load (e.g., tissue).
  • Each of the power curves includes power, voltage, and current control ranges that are defined by the user- selected intensity setting and the measured impedance of the load.
  • the generator 100 may operate in the following monopolar modes, which include, but are not limited to, cut, blend, division with hemostasis, fulgurate, and spray.
  • the generator 100 may operate in the following bipolar modes, including bipolar cutting, bipolar coagulation, automatic bipolar, which operates in response to sensing tissue contact, and various algorithm- controlled vessel sealing modes.
  • the generator 100 may also output energy required to power an ultrasonic transducer, thereby enabling control and modulation of ultrasonic surgical instruments.
  • Each of the RF waveforms may be either monopolar or bipolar RF waveforms, each of which may be continuous or discontinuous and may have a carrier frequency from about 200 kHz to about 500 kHz.
  • continuous waveforms are waveforms that have a 100% duty cycle. In embodiments, continuous waveforms are used to impart a cutting effect on tissue. Conversely, discontinuous waveforms are waveforms that have a non-continuous duty cycle, e.g., below 100%. Discontinuous waveforms may be used to provide coagulation effects to tissue.
  • the generator 100 includes a controller 204, a power supply 206, and an RF inverter 208.
  • the power supply 206 may be high voltage, DC power supplies connected to a common AC source (e.g., line voltage) and provide high voltage, DC power to their respective RF inverter 208, which then convert DC power into a RF waveform through active terminal 210 and return terminal 212 corresponding to the selected mode.
  • the active terminal 210 and the return terminal 212 are coupled to the RF inverter 208 through an isolation transformer 214.
  • the isolation transformer 214 includes a primary winding 214a coupled to the RF inverter 208 and a secondary winding 214b coupled to the active and return terminals 210 and 212.
  • Electrosurgical energy for energizing the monopolar electrosurgical instrument 20 is delivered through the ports 110 and 112, each of which is coupled to the active terminal 210.
  • RF energy is returned through the return electrode pad coupled to the port 118, which in turn, is coupled to the return terminal 212.
  • the secondary winding 214b of the isolation transformer 214 is coupled to the active and return terminals 210 and 212.
  • RF energy for energizing a bipolar electrosurgical instrument is delivered through the ports 114 and 116, each of which is coupled to the active terminal 210 and the return terminal 212.
  • the generator 100 may include a plurality of steering relays or other switching devices configured to couple the active terminal 210 and the return terminals 212 to various ports 110, 112, 114, 116, 118 based on the combination of the monopolar and bipolar electrosurgical instruments 20, 30 being used (e.g. the monopolar instrument 20, the electrosurgical sealing device 51, or the electrosurgical tweezers 52).
  • a plurality of steering relays or other switching devices configured to couple the active terminal 210 and the return terminals 212 to various ports 110, 112, 114, 116, 118 based on the combination of the monopolar and bipolar electrosurgical instruments 20, 30 being used (e.g. the monopolar instrument 20, the electrosurgical sealing device 51, or the electrosurgical tweezers 52).
  • the RF inverter 208 is configured to operate in a plurality of modes, during which the generator 100 outputs corresponding waveforms having specific duty cycles, peak voltages, crest factors, etc. It is envisioned that in other embodiments, the generator 100 may be based on other types of suitable power supply topologies.
  • RF inverter 208 may be a resonant RF amplifier or non-resonant RF amplifier.
  • a non-resonant RF amplifier denotes an amplifier lacking any tuning components, i.e., inductors, capacitors, etc., disposed between the RF inverter and the load, e.g., tissue.
  • the controller 204 includes a processor operably connected to a memory.
  • the controller 204 is operably connected to the power supply 206 and/or RF inverter 208 allowing the processor to control the output of the RF inverter 208 of the generator 100 according to either open and/or closed control loop schemes.
  • a closed loop control scheme is a feedback control loop, in which a plurality of sensors measures a variety of tissue and energy properties (e.g., tissue impedance, tissue temperature, output power, current and/or voltage, etc.), and provides feedback to the controller 204.
  • the controller 204 then controls the power supply 206 and/or the RF inverter 208, which adjust the DC and/or RF waveform, respectively.
  • the generator 100 may also include a plurality of sensors 216, each of which monitors output of the RF inverter 208 of the generator 100.
  • the sensors 216 may be any suitable voltage, current, power, and impedance sensors.
  • the sensors 216 are coupled to the active and return terminals 210 and 212 of the RF inverter 208.
  • the leads 220a and 220b couple the RF inverter 208 to the primary winding 214a of the transformer 214.
  • the sensors 216 are configured to sense voltage, current, and other electrical properties of energy supplied to the active terminal 210 and the return terminal 212.
  • the senor 216 may be coupled to the power supply 206 and may be configured to sense properties of DC current supplied to the RF inverter 208.
  • the controller 204 also receives input (e.g., activation) signals from at least one of the display 120, the input controls 122 of the generator 100, the monopolar instrument 20, the electrosurgical sealing device 51 , or the electrosurgical tweezers 52.
  • the controller 204 adjusts power output by the generator 100 and/or performs other control functions thereon in response to the input signals.
  • the RF inverter 208 includes a plurality of switching elements 228a-228d, which are arranged in an H-bridge topology.
  • RF inverter 208 may be configured according to any suitable topology including, but not limited to, half-bridge, full-bridge, push- pull, and the like.
  • Suitable switching elements include voltage-controlled devices such as transistors, field-effect transistors (FETs), combinations thereof, and the like.
  • the FETs may be formed from silicon, gallium nitride, aluminum nitride, boron nitride, silicon carbide, or any other suitable wide bandgap materials.
  • the RF inverter 208 includes the switching elements 228a-228d, e.g., arranged in a H-bridge, and the output of the power transformer 214 at to the active terminal 210 and the return terminal 212.
  • the switching elements 228a-228d e.g., arranged in a H-bridge
  • the output of the power transformer 214 at to the active terminal 210 and the return terminal 212.
  • the controller 204 is in communication with the RF inverter 208, and in particular, with the switching elements 228a-228d. Controller 204 is configured to output control signals, which may be pulse-width modulated (“PWM”) signals, to switching elements 228a-228d. In particular, controller 204 modulates a control signal supplied to switching elements 228a-228d of the RF inverter 208. The control signal provides PWM signals that operate the RF inverter 208 at a selected carrier frequency.
  • PWM pulse-width modulated
  • controller 204 calculates power characteristics of the RF inverter 208 output and controls the output of the generator 100 based at least in part on the measured power characteristics, which include, but are not limited to, voltage, current, and power at the output of RF inverter 208.
  • the sensor 216 may be a current sensor 300, such as a current transformer, which measures the alternating current in an RF conductor 308, i.e., one of the active and return terminals 210 and 212.
  • the current sensor 300 includes a primary winding 300a electrically coupled to the RF conductor 308 and carries the RF current output by the generator 100.
  • the current sensor 300 also includes a secondary winding 300b, magnetically coupled to the primary winding 300a, which produces an alternating current in the secondary winding 300b that is proportional to the current in the primary winding 300a, allowing for measuring of the RF current.
  • the secondary winding 300b is coupled to a current sense circuit 302, which is in communication with and provides RF current sensor measurements to the controller 204 based on the current measured by the secondary winding 300b.
  • the current sensor 300 could also be a conventional current sense transformer, with a high permeability toroid and 3 windings.
  • the RF current sensor 300 may be a Rogowski coil that measures alternating current (e.g., RF current) and includes an outer conductor coil (e.g., toroid) that acts as an active conductor wrapped around an inner conductor that acts as a return conductor with a lead carrying the current passing through the center of the coil.
  • the coil may have any suitable shape such as helical, toroidal, etc.
  • the coil may have a polygonal cross-section.
  • the Rogowski coil may include a low permeability core (e.g., air core) that provides a voltage output having a time-derivate of the current being measured to a conditioning circuit that integrates the output to provide a voltage signal indicative of the current.
  • the Rogowski coil may be disposed on a printed circuit board such that an RF conductor 308 carrying the current passes through the Rogowski coil.
  • the current sensor 300 is coupled to a conditioning circuit, which outputs a sensor signal corresponding to the detected RF current passing through the conductor 308.
  • a more detailed description of the Rogowski coil RF current sensor is provided in U.S. Patent No. 9,116,179, titled “System and Method for Voltage and Current Sensing”, the entire disclosure of which is incorporated herein by reference.
  • a stimulation circuit 320 includes a stimulating conductor 322 electrically coupled to a third winding 300c of the RF sensor 300.
  • the third winding 300c is magnetically coupled to the secondary winding 300b and produces an alternating current in the secondary winding 300b that is proportional to the current in the third winding 300c, allowing for measuring of the current of a test signal generated by the stimulation circuit 320.
  • the stimulation circuit 320 is used to verify the functionality of the current sensor 300 and associated signal chain (e.g., filters, amplifiers, A/D converter, etc.).
  • the stimulation circuit 320 outputs a test signal, which is measured by the current sensor 300 and its output is analyzed and compared by the controller 204 with a known sensor response (e.g., values stored in memory) corresponding to the test signal. If the measured test signal parameter matches the stored sensor response, the controller 204 outputs an indication that the current sensor 300 is functioning properly. If the test signal does not match, the controller 204 outputs an error alert, indicating the current sensor 300 is malfunctioning.
  • a known sensor response e.g., values stored in memory
  • the stimulation circuit 320 outputs a test signal, which may be a square wave signal with known current at or near (e.g., +/- 5 kHz) the RF output frequency, e.g., from about 200 kHz to about 500 kHz.
  • a test signal which may be a square wave signal with known current at or near (e.g., +/- 5 kHz) the RF output frequency, e.g., from about 200 kHz to about 500 kHz.
  • the current sensor 300 may be checked at three main frequencies of interest, i.e., fundamental (first) frequency, 3rd harmonic frequency, and 5th harmonic frequency. To verify the correct operation, the gain and phase is verified at one or more frequencies over the frequency range of interest.
  • correct operation of the current sensor 300 may be verified at the fundamental frequency (e.g., 443kHz, which is the fundamental frequency for monopolar cut mode of the RF inverter 208), at the 3rd harmonic frequency, (e.g., 1.33MHz), and the 5th harmonic frequency (e.g., 2.22MHz).
  • the current sensor signal chain may also be tested by injecting a sinusoidal current of known amplitude and phase at each of these frequencies in turn, a square waveform may be used for this rather than a sine waveform, which is more difficult to reproduce.
  • a square waveform with positive and negative symmetry may be represented by its Fourier series, consisting of a series of odd harmonics (i.e., 1st, 3rd, and 5th harmonics).
  • the fundamental frequency of the test signal may be extracted by analog hardware filters or digital signal processing.
  • the controller 204 digitally samples the output of the current sensor 300 and uses the Goertzel algorithm, a computationally efficient method for evaluating amplitude and phase at a single frequency.
  • the controller 204 also uses the Goertzel algorithm to extract the amplitude and phase at the 3rd and 5th harmonics by running the algorithm again on the same set of sampled data at those frequencies.
  • the stimulation circuit 320 may also repeat injection of test signals at the other frequencies of interest (e.g., the 3rd and 5th harmonics) to achieve better signal integrity. It is envisioned that different harmonic frequencies may be used for different modes being used.
  • FIG. 5 shows a method for verifying accuracy of the current sensor 300, portions of which may be implemented as software instructions stored in memory and executable by a processor.
  • the controller 204 initiates a test process by instructing the stimulation circuit 320 to output a test signal.
  • the test signal substantially matches the RF signal that the generator 100 generates for a selected operational mode, e.g., the test signal has the same fundamental frequency as the RF signal.
  • the test signal is transmitted to the current sensor 300 by the stimulation circuit 320.
  • the current sensor 300 outputs a measured test signal, which is provided to the controller 204.
  • the measured test signal provided to the controller 204 may include a set of sampled data as a plurality of digital values.
  • the controller 204 processes the measured test signal data using the Goertzel algorithm to extract one or more measured test signal parameters from the sample data, such as the amplitude and phase.
  • another signal processing algorithm may be used to determine signal properties of interest, e.g., amplitude and phase.
  • the controller 204 compares the calculated test signal parameters to stored test signal parameters, which include amplitude and phase of the test signal. The controller 204 determines whether the calculated signal parameters match (e.g., within a prescribed error threshold) the stored signal parameters to determine whether the current sensor 300 is operating within the stored signal parameters.
  • the controller 204 determines that the current sensor 300 is operating properly, i.e., accurately, and enables the generator 100 to output RF energy.
  • the controller 204 may also output a message on the display 120 stating the current sensor 300 is operational.
  • the controller 204 determines that the current sensor 300 is malfunctioning and disables the generator 100.
  • the controller 204 may also output a message on the display 120 stating the current sensor 300 is malfunctioning.
  • the method may be a repeated multiple times to inject a test signal corresponding to each of multiple harmonics of the test signal/RF signal.
  • the controller 204 may perform the same comparison step to determine whether the current sensor 300 is operating correctly. Thus, if any of the individual harmonic test signal parameters does not match, then the controller 204 would indicate that the current sensor 300 is faulty. Conversely, if all of the parameters of each individual harmonic test signal match, the current sensor 300 is operational and the controller 204 controls operation of the generator 100 in the manner described above.
  • An electrosurgical generator comprising: a radio frequency (RF) inverter configured to provide an output RF waveform; a stimulation circuit configured to output a test signal; a sensor coupled to at least the stimulation circuit, with the sensor configured to receive the test signal and to output a measured test signal having at least one test signal parameter; and a processor communicatively coupled to the sensor and configured to: receive the measured test signal from the sensor; compare the at least one test signal parameter to a corresponding at least one stored test signal parameter; determine an operational status of the sensor based on the comparison; and control the RF inverter based on the determined operational status of the sensor.
  • RF radio frequency
  • Example 2 The electrosurgical generator according to example 1, wherein the sensor is coupled to the RF inverter, and further configured to receive the output RF waveform and to provide an output signal to the processor based thereon.
  • Example 3 The electrosurgical generator according to example 1, wherein the processor is further configured to determine the at least one test signal parameter by processing the measured test signal using a Goertzel algorithm.
  • Example 4 The electrosurgical generator according to example 3, wherein the measured test signal is a square waveform, and the at least one test signal parameter is at least one of an amplitude or a phase.
  • Example 5 The electrosurgical generator according to example 4, wherein the square waveform and the output RF waveform have a common fundamental frequency.
  • Example 6 The electrosurgical generator according to example 4, wherein the processor is further configured to process the measured test signal at a plurality of harmonic frequencies of the square waveform.
  • Example 7 The electrosurgical generator according to example 1, wherein the processor is further configured to determine that the sensor is faulty based on a mismatch between the at least one test signal parameter and the at least one stored test signal parameter.
  • Example 8 The electrosurgical generator according to example 7, further comprising a display, wherein the processor is further configured to output an alert on the display in response to determining the sensor is faulty.
  • Example 9 The electrosurgical generator according to example 1, further comprising an isolation transformer coupled to the RF inverter via a conductor.
  • Example 10 The electrosurgical generator according to example 9, wherein the sensor is a current sensor comprising a first winding galvanically coupled to the conductor.
  • Example 11 The electrosurgical generator according to example 10, further comprising a sensing circuit for providing RF current sensor measurements to the processor.
  • Example 12 The electrosurgical generator according to example 11, wherein the current sensor further includes: a second winding galvanically coupled to the sensing circuit.
  • Example 13 The electrosurgical generator according to example 12, wherein the current sensor further includes: a third winding galvanically coupled to the stimulation circuit.
  • Example 14 A method for verifying accuracy of a sensor in an electrosurgical generator, the method comprising: receiving, by a sensor, a test signal from a stimulation circuit, the sensor being coupled to a radio frequency (RF) inverter providing an output RF waveform; outputting, by the sensor, a measured test signal to a processor, wherein the measured test signal is based on the received test signal and comprises at least one measured test signal parameter ; comparing, at the processor, the measured test signal parameter to a stored test signal parameter; determining, at the processor, an operational status of the sensor based on the comparison of the measured test signal parameter to the stored test signal parameter; and controlling, via the processor, the RF inverter based on the operational status of the sensor.
  • RF radio frequency
  • Example 15 The method according to example 14, further comprising determining, by the processor, the measured test signal parameter by using a Goertzel algorithm to process the measured test signal from the sensor.
  • Example 16 The method according to example 15, wherein the measured test signal is a square waveform and the measured test signal parameter is at least one of amplitude or phase.
  • Example 17 The method according to example 16, wherein the square waveform and the output RF waveform have a common fundamental frequency.
  • Example 18 The method according to example 16, further comprising processing the measured test signal at a plurality of harmonic frequencies of the square waveform.
  • Example 19 The method according to example 14, further comprising determining, at the processor, that the sensor is faulty based on a mismatch between the measured test signal parameter and the stored test signal parameter.
  • Example 20 The method according to example 19, further comprising outputting an alert on a display of the electrosurgical generator in response to determining the sensor is faulty.

Landscapes

  • Health & Medical Sciences (AREA)
  • Surgery (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Biomedical Technology (AREA)
  • Otolaryngology (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Plasma & Fusion (AREA)
  • Physics & Mathematics (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Medical Informatics (AREA)
  • Molecular Biology (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Surgical Instruments (AREA)

Abstract

L'invention concerne un générateur électrochirurgical incluant un onduleur radiofréquence (RF) pour délivrer une forme d'onde RF et un capteur couplé à l'onduleur RF pour mesurer un ou plusieurs paramètres de la forme d'onde RF. Le générateur inclut également un circuit de stimulation couplé au capteur pour délivrer un signal de test via le capteur et un processeur pour recevoir un signal de test mesuré provenant du capteur. Le processeur compare également un paramètre de signal de test mesuré à un paramètre de signal de test stocké, détermine un état opérationnel du capteur sur la base d'une comparaison entre le paramètre de signal de test mesuré et un paramètre de signal de test stocké, et commande l'onduleur RF sur la base de l'état opérationnel du capteur.
PCT/IB2024/060145 2023-10-18 2024-10-16 Système électrochirurgical et procédé de vérification de la précision d'un capteur de courant Pending WO2025083577A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US202363591152P 2023-10-18 2023-10-18
US63/591,152 2023-10-18

Publications (1)

Publication Number Publication Date
WO2025083577A1 true WO2025083577A1 (fr) 2025-04-24

Family

ID=93378924

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2024/060145 Pending WO2025083577A1 (fr) 2023-10-18 2024-10-16 Système électrochirurgical et procédé de vérification de la précision d'un capteur de courant

Country Status (1)

Country Link
WO (1) WO2025083577A1 (fr)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060224152A1 (en) * 2005-03-31 2006-10-05 Sherwood Services Ag Method and system for compensating for external impedance of an energy carrying component when controlling an electrosurgical generator
US20130035679A1 (en) * 2011-08-01 2013-02-07 TYCO Healthare Group LP Electrosurgical Apparatus with Real-Time RF Tissue Energy Control
US20130053840A1 (en) * 2011-08-30 2013-02-28 Tyco Healthcare Group Lp System and Method for DC Tissue Impedance Sensing
US9116179B2 (en) 2012-12-17 2015-08-25 Covidien Lp System and method for voltage and current sensing
US20160310202A1 (en) * 2015-04-23 2016-10-27 Covidien Lp Control systems for electrosurgical generator
US20190046256A1 (en) * 2012-04-09 2019-02-14 Covidien Lp Method for employing single fault safe redundant signals

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060224152A1 (en) * 2005-03-31 2006-10-05 Sherwood Services Ag Method and system for compensating for external impedance of an energy carrying component when controlling an electrosurgical generator
US20130035679A1 (en) * 2011-08-01 2013-02-07 TYCO Healthare Group LP Electrosurgical Apparatus with Real-Time RF Tissue Energy Control
US20130053840A1 (en) * 2011-08-30 2013-02-28 Tyco Healthcare Group Lp System and Method for DC Tissue Impedance Sensing
US20190046256A1 (en) * 2012-04-09 2019-02-14 Covidien Lp Method for employing single fault safe redundant signals
US9116179B2 (en) 2012-12-17 2015-08-25 Covidien Lp System and method for voltage and current sensing
US20160310202A1 (en) * 2015-04-23 2016-10-27 Covidien Lp Control systems for electrosurgical generator

Similar Documents

Publication Publication Date Title
US11864814B2 (en) System and method for harmonic control of dual-output generators
US12426936B2 (en) Ultrasonic and radiofrequency energy production and control from a single power converter
CN103635157B (zh) 具有实时射频组织能量控制的电外科装置
US7956620B2 (en) System and method for augmented impedance sensing
EP2353533B1 (fr) Vague carrée pour obturation de vaisseaux
EP2750618B1 (fr) Système de détection dc d'impédance de tissu
EP2499983B1 (fr) Capteur de courant isolé
US10869712B2 (en) System and method for high frequency leakage reduction through selective harmonic elimination in electrosurgical generators
US20210361337A1 (en) Independent control of dual rf bipolar electrosurgery
US20210361339A1 (en) Independent control of dual rf monopolar electrosurgery with shared return electrode
WO2025083577A1 (fr) Système électrochirurgical et procédé de vérification de la précision d'un capteur de courant
US20210361340A1 (en) Independent control of dual rf electrosurgery
US20250143774A1 (en) Independent control of dual rf electrosurgery

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 24801664

Country of ref document: EP

Kind code of ref document: A1