Abstract: Systems and methods for estimating tissue parameters, including mass of tissue to be treated and a thermal resistance scale factor between the tissue and an electrode of an energy delivery device, are disclosed. The method includes sensing tissue temperatures, estimating a mass of the tissue and a thermal resistance scale factor between the tissue and an electrode, and controlling an electrosurgical generator based on the estimated mass and the estimated thermal resistance scale factor. The method may be performed iteratively and non-iteratively. The iterative method may employ a gradient descent algorithm that iteratively adds a derivative step to the estimates of the mass and thermal resistance scale factor until a condition is met. The non-iterative method includes selecting maximum and minimum temperature differences and estimating the mass and the thermal resistance scale factor based on a predetermined reduction point from the maximum temperature difference to the minimum temperature difference.

Abstract: A method for operating an electrosurgical generator is disclosed, including receiving a high level algorithm at an electrosurgical generator including a processor, a power supply, and a radio frequency amplifier, the high level algorithm including an interpreted language script, processing the interpreted language script through an interpreter engine executed by the processor, selecting at least one of a plurality of configuration files stored in the electrosurgical generator based on the interpreted language script to effect a desired mode of operation, and executing the interpreted language script based on the selected one of the plurality of configuration files to generate instructions which cause the electrosurgical generator to control at least one of the power supply and the radio frequency amplifier to generate radio frequency energy according to the selected one of the plurality of configuration files.

Abstract: Controlling a level of electrosurgical energy provided to tissue based on detected arcing patterns or impedance changes. The drag force imposed on an electrode or blade of an electrosurgical instrument may be controlled by adjusting the level of electrosurgical energy based on the arcing patterns or impedance changes. The arcing patterns or impedance changes may be detected by sensing and analyzing voltage and/or current waveforms of the electrosurgical energy. The current and/or voltage waveform analysis may involve calculating impedance based on the voltage and current waveforms and calculating changes in impedance over time. The waveform analysis may involve detecting harmonic distortion using FFTs, DFTs, Goertzel filters, polyphase demodulation techniques, and/or bandpass filters. The waveform analysis may involve determining a normalized difference or the average phase difference between the voltage and current waveforms.

Abstract: A control system for use with an electrosurgical generator which delivers electrosurgical energy to tissue has a control module. The module includes a processor executing an algorithm. The algorithm has the steps of determining a sensed voltage value corresponding to a sensed voltage signal output by the electrosurgical generator and determining a sensed current value corresponding to a sensed current signal output by the electrosurgical generator. The algorithm has the steps of determining phase information corresponding to a phase shift between the voltage signal and the current signal and determining a characteristic related to the electrosurgical energy delivered to the tissue using the phase information, the sensed voltage value and the sensed current value.

Abstract: A jaw angle detection system for an end effector assembly includes a first electrical contact that connects to a first jaw member and connects to a generator. A sensor connects to a second jaw member (or an actuator) and connects to the generator, and configured to move relative to the first electrical contact upon movement of the second jaw member (or the actuator) when the first and second jaw members are moved to close about tissue disposed therebetween. Information relating to the position of the sensor relative to the first electrical contact is relayed back to the generator to determine an angle between the first and second jaw members.

Abstract: An electrosurgical system is disclosed. The electrosurgical system includes an electrosurgical generator adapted to supply electrosurgical energy to tissue. The electrosurgical generator includes impedance sensing circuitry which measures impedance of tissue, a microprocessor configured to determine whether a tissue reaction has occurred as a function of a minimum impedance value and a predetermined rise in impedance, wherein tissue reaction corresponds to a boiling point of tissue fluid, and an electrosurgical instrument including at least one active electrode adapted to apply electrosurgical energy to tissue.

Abstract: An electrosurgical generator includes an electrosurgical energy output configured to deliver electrosurgical energy to a bipolar end effector assembly in a conductive fluid environment for treating tissue. A controller having a processor is configured to control a waveform of the electrosurgical energy such that the waveform oscillates between a cut phase for initiating and sustaining tissue cutting, wherein the waveform includes a cut energy greater than the energy needed to create and sustain arcing, and a hemostasis phase, for desiccating/coagulating tissue, wherein the waveform includes a hemostasis energy less than the energy needed to sustain arcing.

Abstract: The present disclosure relates to an electrosurgical generator which includes a controller configured to generate a first pulse train having at least one first control pulse and at least one first reset pulse. The controller also includes a second pulse train having at least one second control pulse and at least one second reset pulse. The first control pulse(s) and the second control pulse(s) are asynchronous and the reset pulse(s) are synchronous. The electrosurgical generator also includes an RF output stage which includes a first switching element and a second switching element. The control pulses are configured to activate the first switching element and second switching elements, respectively, in an asynchronous fashion to generate a non-continuous RF waveform.

Abstract: The present disclosure relates to an electrosurgical generator which includes a controller configured to generate a first pulse train having at least one first control pulse and at least one first reset pulse. The controller also includes a second pulse train having at least one second control pulse and at least one second reset pulse. The first control pulse(s) and the second control pulse(s) are asynchronous and the reset pulse(s) are synchronous. The electrosurgical generator also includes an RF output stage which includes a first switching element and a second switching element. The control pulses are configured to activate the first switching element and second switching elements, respectively, in an asynchronous fashion to generate a non-continuous RF waveform.

Abstract: Controlling a level of electrosurgical energy provided to tissue based on detected arcing patterns or impedance changes. The drag force imposed on an electrode or blade of an electrosurgical instrument may be controlled by adjusting the level of electrosurgical energy based on the arcing patterns or impedance changes. The arcing patterns or impedance changes may be detected by sensing and analyzing voltage and/or current waveforms of the electrosurgical energy The current and/or voltage waveform analysis may involve calculating impedance based on the voltage and current waveforms and calculating changes in impedance over time. The waveform analysis may involve detecting harmonic distortion using FFTs, DFTs, Goertzel filters, polyphase demodulation techniques, and/or bandpass filters. The waveform analysis may involve determining a normalized difference or the average phase difference between the voltage and current waveforms.

Abstract: A controller for an electrosurgical generator includes an RF inverter, a signal processor, a software compensator, a hardware compensator, and an RF inverter controller. The RF inverter generates an electrosurgical waveform and the signal processor outputs a measured value of at least one of a voltage, a current, or power of the electrosurgical waveform. The software compensator generates a desired value for at least one of the voltage, the current, or the power of the electrosurgical waveform, and the hardware compensator generates a phase shift based on the measured value and the desired value. The RF inverter controller generates a pulse-width modulation (PWM) signal based on the phase shift to control the RF inverter.

Abstract: A control system for use with an electrosurgical generator which delivers electrosurgical energy to tissue has a control module. The module includes a processor executing an algorithm. The algorithm has the steps of determining a sensed voltage value corresponding to a sensed voltage signal output by the electrosurgical generator and determining a sensed current value corresponding to a sensed current signal output by the electrosurgical generator. The algorithm has the steps of determining phase information corresponding to a phase shift between the voltage signal and the current signal and determining a characteristic related to the electrosurgical energy delivered to the tissue using the phase information, the sensed voltage value and the sensed current value.

Abstract: A jaw angle detection system for an end effector assembly includes a first electrical contact that connects to a first jaw member and connects to a generator. A sensor connects to a second jaw member (or an actuator) and connects to the generator, and configured to move relative to the first electrical contact upon movement of the second jaw member (or the actuator) when the first and second jaw members are moved to close about tissue disposed therebetween. Information relating to the position of the sensor relative to the first electrical contact is relayed back to the generator to determine an angle between the first and second jaw members.

Abstract: An electrosurgical system is disclosed. The electrosurgical system includes an electrosurgical generator adapted to supply electrosurgical energy to tissue. The electrosurgical generator includes impedance sensing circuitry which measures impedance of tissue, a microprocessor configured to determine whether a tissue reaction has occurred as a function of a minimum impedance value and a predetermined rise in impedance, wherein tissue reaction corresponds to a boiling point of tissue fluid, and an electrosurgical instrument including at least one active electrode adapted to apply electrosurgical energy to tissue.

Abstract: An electrosurgical generator includes an electrosurgical energy output configured to deliver electrosurgical energy to a bipolar end effector assembly in a conductive fluid environment for treating tissue. A controller having a processor is configured to control a waveform of the electrosurgical energy such that the waveform oscillates between a cut phase for initiating and sustaining tissue cutting, wherein the waveform includes a cut energy greater than the energy needed to create and sustain arcing, and a hemostasis phase, for desiccating/coagulating tissue, wherein the waveform includes a hemostasis energy less than the energy needed to sustain arcing.

Abstract: An electrosurgical system is disclosed. The electrosurgical system includes an electrosurgical generator adapted to supply electrosurgical energy to tissue. The electrosurgical generator includes impedance sensing circuitry which measures impedance of tissue, a microprocessor configured to determine whether a tissue reaction has occurred as a function of a minimum impedance value and a predetermined rise in impedance, wherein tissue reaction corresponds to a boiling point of tissue fluid, and an electrosurgical instrument including at least one active electrode adapted to apply electrosurgical energy to tissue.

Abstract: An electrosurgical system is disclosed. The electrosurgical system includes an electrosurgical generator adapted to supply electrosurgical energy to tissue. The electrosurgical generator includes impedance sensing circuitry which measures impedance of tissue, a microprocessor configured to determine whether a tissue reaction has occurred as a function of a minimum impedance value and a predetermined rise in impedance, wherein tissue reaction corresponds to a boiling point of tissue fluid, and an electrosurgical instrument including at least one active electrode adapted to apply electrosurgical energy to tissue.

Abstract: An end-effector assembly includes first and second jaw members disposed in opposing relation relative to one another, at least one of the jaw members moveable from an open position to a closed position for grasping tissue therebetween. First and second conductive plates are disposed on opposing surfaces of corresponding first and second jaw members. First and second compressible membranes are configured to electrically connect corresponding first and second conductive plates to a surgical field when subjected to a compression bias.

Abstract: A method for operating an electrosurgical generator is disclosed, including receiving a high level algorithm at an electrosurgical generator including a processor, a power supply, and a radio frequency amplifier, the high level algorithm including an interpreted language script, processing the interpreted language script through an interpreter engine executed by the processor, selecting at least one of a plurality of configuration files stored in the electrosurgical generator based on the interpreted language script to effect a desired mode of operation, and executing the interpreted language script based on the selected one of the plurality of configuration files to generate instructions which cause the electrosurgical generator to control at least one of the power supply and the radio frequency amplifier to generate radio frequency energy according to the selected one of the plurality of configuration files.

Abstract: An end-effector assembly includes first and second jaw members disposed in opposing relation relative to one another, at least one of the jaw members moveable from an open position to a closed position for grasping tissue therebetween. First and second conductive plates are disposed on opposing surfaces of corresponding first and second jaw members. First and second compressible membranes are configured to electrically connect corresponding first and second conductive plates to a surgical field when subjected to a compression bias.