scispace - formally typeset
Search or ask a question
Patent

Digital waveform generation for electrosurgical generators

TL;DR: In this paper, an electrosurgical generator with an improved microprocessor was proposed to generate output waveforms in the form of a serial digital output from the microprocessor, which is then transformed into an output RF output in an amplifier stage.
Abstract: An electrosurgical generator (10) has an improved design for generating output waveforms using a microprocessor (15). The waveforms are generated in the form of a serial digital output from the microprocessor (15). The serial digital output is transformed into an electrosurgical RF output in an amplifier stage. The improved design also includes a monitoring circuit to continuously monitor the serial digital output by time-averaging the output, and then comparing that value with a threshold. The electrosurgical generator (10) comprises a microprocessor (15), an algorithm in the microprocessor (15) capable of toggling an output port of the microprocessor (15), an output amplifier (16), an adjustable high voltage DC power supply (17), a patient circuit including an active electrode (12) and a return electrode (13). The electrosurgical generator (10) may further comprise a mode selector (20) for selecting one of a plurality of pulse patterns in the serial digital output, and a plurality of command sequences in the algorithm, where each command sequence is designed to produce one of the plurality of patterns. There may also be a tank damp circuit (22) for reducing the amplitude of voltage spikes in the electrosurgical output, and a pulse suppression circuit. The monitoring circuit comprises a low pass filter (19) and a comparator to verify operation of the waveform generator.
Citations
More filters
Patent
10 Jun 2011
TL;DR: In this article, a surgical stapling device particularly suited for endoscopic procedures is described, which includes a handle assembly and an elongated body extending distally from the handle assembly.
Abstract: A surgical stapling device particularly suited for endoscopic procedures is described The device includes a handle assembly and an elongated body extending distally from the handle assembly The distal end of the elongated body is adapted to engage a disposable loading unit A control rod having a proximal end operatively connected to the handle assembly includes a distal end extending through the elongated body A control rod locking member is provided to prevent movement of the control rod until the disposable loading unit is fully secured to the elongated body of the stapling device

2,013 citations

Patent
30 Sep 2004
TL;DR: In this paper, a surgical stapling instrument (1) comprises a body portion (2, 3), a handle (4), and a staple fastening assembly (8), which includes a curved cartridge (10), which comprises at least one curved open row of staples, and a curved anvil (22), which is adapted to cooperate with the cartridge for forming the ends of the staples exiting from the cartridge.
Abstract: A surgical stapling instrument (1) comprises a body portion (2, 3), a handle (4) and a staple fastening assembly (8). The staple fastening assembly (8) includes a curved cartridge (10), which comprises at least one curved open row of staples, and a curved anvil (22), which is adapted to cooperate with the cartridge (10) for forming the ends of the staples exiting from the cartridge (10). The staple fastening assembly (8) is adapted to allow unobstructed access towards the concave inner faces of the cartridge (10) and the anvil (22). The cartridge (10) can be moved towards the anvil (22) from a spaced position for positioning tissue therebetween to a closed position for clamping the tissue. Preferably, a knife is contained within the cartridge (10) and is positioned such that there is at least one row of staples on at least one side of the knife.

1,502 citations

Patent
14 Jun 2016
TL;DR: Newness and distinctiveness is claimed in the features of ornamentation as shown inside the broken line circle in the accompanying representation as discussed by the authors, which is the basis for the representation presented in this paper.
Abstract: Newness and distinctiveness is claimed in the features of ornamentation as shown inside the broken line circle in the accompanying representation.

1,500 citations

Patent
21 Apr 2011
TL;DR: In this paper, a surgical instrument can comprise a channel configured to support a staple cartridge and, in addition, an anvil pivotable between open and closed positions relative to the channel.
Abstract: A surgical instrument can comprise a channel configured to support a staple cartridge and, in addition, an anvil pivotable between open and closed positions relative to the channel. The surgical instrument can further comprise a cutting member configured to incise tissue positioned captured between the staple cartridge and the anvil and, in addition, means for stopping the cutting member prior to a distal end datum, wherein the distal end datum can be defined by the distal-most staple cavity in the staple cartridge. In such embodiments, the incision within the tissue may not extend beyond the portion of the tissue that has been stapled.

1,498 citations

Patent
19 Jun 1996
TL;DR: In this article, the authors present a controller that can cause the generator to supply a blended output signal alternating constantly between a first output signal across the output connections in which the radio frequency output voltage developed across output connections is limited to at least a first predetermined threshold value for cutting or vaporization of tissue, and a second output signal with a power supply coupled to the output stage for supplying power to output stage.
Abstract: In an electrosurgical generator for generating radio frequency power, the generator includes a radio frequency output stage having two or more output connections, and a power supply coupled to the output stage for supplying power to the output stage. A controller is operable to cause the generator to supply a blended output signal alternating constantly between a first output signal across the output connections in which the radio frequency output voltage developed across the output connections is limited to at least a first predetermined threshold value for cutting or vaporisation of tissue, and a second output signal across the output connections in which the radio frequency output voltage developed across the output connections is limited to a second threshold value for coagulation. There is also provided adjustment means, operable by a user of the electrosurgical generator, for changing between various preset settings for the blended signal, the preset settings each having a predetermined duty cycle of the blended signal that is limited to the first threshold value for cutting or vaporisation, and a predetermined duty cycle of the blended signal that is limited to the second threshold value for coagulation.

1,486 citations

References
More filters
Patent
09 Sep 1994
TL;DR: In this article, an electrosurgical generator (11) control responds to tissue impedance between active and return electrodes (12 and 13) during desiccation and alters the output of the generator.
Abstract: An electrosurgical generator (11) control responds to tissue impedance between active and return electrodes (12 and 13) during desiccation. Active and return generator leads supply energy (25) and a user control (16) sets the level of energy (25) desired for electrosurgery. Voltage and current sensing circuits (19) respond to high frequency energy (25) in the leads to signal voltage and current in the leads. A multiplier (21) receives the signals to calculate power. A clock (23) sets units of time during which power calculation. An integrator (24) calculates the energy (25) supplied through the leads per time unit. The user control (16) sets a reference signal (26) for the energy (25) level desired. A correlation circuit (27) receives the energy (30) calculations from the integrator (24) and the reference signal (26) and provides a feedback signal (28) to indicate when the energy (25) calculation equals the user control (16) setting for altering the generator supply of energy (25) to the leads. A counter (38) assesses the number of packets of energy (40) delivered against a setting of the user control (16) and the total energy (25) delivered is a function of multiple packet sequences containing pulses wherein the time between the pulses is controlled by the user control (16). The method uses the automatic control (10) in measuring impedance during tissue desiccation and altering the output of an electrosurgical generator (11).

634 citations

Patent
31 Jan 1991
TL;DR: In this article, an improved method and apparatus for measuring the total energy delivered to a patient during an electrosurgical procedure is presented, where the patient is positioned atop a dispersive plate constituting a first electrode.
Abstract: An improved method and apparatus for measuring the total energy delivered to a patient during an electrosurgical procedure. An electrosurgical target (the patient) is positioned atop a dispersive plate constituting a first electrode. The patient is included in the circuit comprising an electrosurgical generator, the plate electrode and a surgical instrument constituting a second electrode. A mathematical relationship between the current in the circuit and the load impedance is established for selected power settings of said generator. Current in the circuit is measured during electrosurgery by suitable means such as a current transformer. A computing device such as a microprocessor determines the impedence according to the relationship between current and impedence for the particular generator power setting being used. The microprocessor then computes the power delivered to the patient from the current and impedance values. The delivered power is integrated over time to determine the total energy delivered to the patient. The microprocessor may be further programmed to shut off the generator when a selected maximum total energy is delivered.

103 citations

Patent
20 Feb 1986
TL;DR: In this paper, an electrosurgical generator including a patient circuit including an active electrode and a return electrode, a pulse train generating circuit, an M×N storage device having M memory locations where M>1 and where each location contains N storage positions where N≧1, the storage device storing at least one, K-bit binary signal, where 1
Abstract: An electrosurgical generator including a patient circuit including an active electrode and a return electrode; a pulse train generating circuit an M×N storage device having M memory locations where M>1 and where each location contains N storage positions where N≧1, the storage device storing at least one, K-bit binary signal, where 1

89 citations

Patent
Masao Suda1
04 Jun 1993
TL;DR: In this paper, an electrosurgical signal generator includes PROM for previously storing data representative of electrosurgery high-frequency currents, and the data is read out from PROM to produce the electrosural highfrequency current corresponding to the selected operation mode.
Abstract: In an electrosurgical power supply apparatus combined with an electronic endoscope system, there is provided an electrosurgical signal generator. The electrosurgical signal generator includes PROM for previously storing data representative of electrosurgical high-frequency currents. In response to a selection signal of an electrosurgical operation mode, the data is read out from PROM to produce the electrosurgical high-frequency current corresponding to the selected electrosurgical operation mode.

76 citations

Patent
16 Feb 1989
TL;DR: In this article, a waveform generator for electrosurgical devices is described, which includes a MxNxP storage device and a parallel-to-series conversion device.
Abstract: A waveform generator for electrosurgical apparatus disclosed includes a MxNxP storage device and a parallel to series conversion device. For the storage device, M is the maximum number of different waveforms being stored, N equals the number of bits being output from the storage device at a time and P is the maximum number of N bits that can be stored for each waveform. An address counter selects the next N bits of the waveform and these N bits are loaded from the storage device into the conversion device and output in a sequential or series output signal to drive the RF power amplifier of electrosurgical apparatus. The output signal has a bit rate N times faster than the storage device is accessed.

26 citations