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.
Abstract:
A control system (10) and method for the operation of neurosurgical bipolar electrodes (11) provides a source of high frequency energy (13') connected to bipolar electrodes (11). Contacting surfaces are on the bipolar electrodes (11) of highly electrically conductive material. A current transducer attached to the source of high frequency energy (13') measures (20) the RMS current applied between the contact surfaces (25). A current transducer attached to the source of high frequency energy (13') provides a signal (26) correlated to the instantaneous values of the RMS voltage between the contacts. A control connects to the source of high frequency energy (13') for initially regulating the RMS current applied by the contacting surfaces in response to the impedance until the signal (19) divided by the measure (20) which is representative of the instantaneous impedance of the load reaches a predetermined value. The control regulates the RMS power applied by the contacting surfaces in accord with the impedance until the signal (19) divided by the measure (20) reaches a predefined value. The control responds to the measure (20) and the signal (19) so that the RMS voltage applied to the load being treated between the contacting surfaces regulated while its impedance is monitored until a prescribed value is reached. The control regulates the RMS voltage applied in accord with the impedance by changing the RMS voltage to a percentage of that applied until the prescribed value is obtained so that the tissues stay moist and are coagulated without drying and carbonizing or turning to eschar.
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.