Abstract: An electrosurgical system includes a generator for generating radio frequency power, and an electrosurgical instrument including at least three electrodes and. The generator includes a radio frequency output stage having at least a pair of RF output lines, and a power supply coupled to the output stage for supplying power to the output stage. A controller is operable to limit the radio frequency output voltage developed across the output lines to at least a first predetermined threshold value to produce a cutting RF waveform, and a second threshold value to produce a coagulating RF waveform. In a combined mode, the controller delivers both cutting and coagulating waveforms, either simultaneously or by alternating constantly between the first and second threshold values to form a blended signal.

Abstract: A bipolar electrosurgical instrument for cutting and sealing tissue comprises first and second jaw members movable between open and closed positions so as to be capable of grasping tissue therebetween. The first jaw member includes first and second coagulating electrodes on its inner surface, and an insulating member separating the first and second electrodes. The first jaw member also includes a third cutting electrode on an outer surface separate from the inner surface, and the second jaw member has a tissue-contacting surface which is electrically insulating over its entire surface. The electrosurgical instrument is capable of selectively causing coagulation of tissue between the first and second electrodes, and/or the cutting of tissue contacted by the third electrode.

Abstract: An electrosurgical system includes a generator (10) for generating radio frequency power, and an electrosurgical instrument (12) including at least three electrodes. The generator comprises a radio frequency output stage having at least a pair of output lines (60C), and a power supply (66) coupled to the output stage for supplying power to the output stage. The generator also includes a controller (72) capable of varying a radio frequency signal supplied to the output lines, and a switching circuit (62) having three or more output connections (62A, 62B, 62C) each electrically connected with a respective one of the at least three electrodes. This switching circuit is operable to vary the connections between the output lines (60C) and the output connections (62A, 62B, 62C).

Abstract: An electrosurgical system includes a generator for generating radio frequency power, and an electrosurgical instrument including at least three electrodes and. The generator includes a radio frequency output stage having at least a pair of RF output lines, and a power supply coupled to the output stage for supplying power to the output stage. A controller is operable to limit the radio frequency output voltage developed across the output lines to at least a first predetermined threshold value to produce a cutting RF waveform, and a second threshold value to produce a coagulating RF waveform. In a combined mode, the controller delivers both cutting and coagulating waveforms, either simultaneously or by alternating constantly between the first and second threshold values to form a blended signal.

Abstract: An electrosurgical cutting blade (1) comprises a first electrode (2), a second electrode (3), and an electrical insulator (4) separating the first and second electrodes. The first and second electrodes have dissimilar characteristics (cross-sectional area, thermal conductivity etc.) such that the first electrode (2) is encouraged to become an active electrode and the second electrode (3) is encouraged to become a return electrode. The spacing between the first and second electrodes (between 0.25 mm and 3.0 mm) and the peak voltage supplied to the electrodes (2 and 3) are both selected such that arcing does not occur directly between the electrodes, but between the first electrode and the tissue at the target site. The arrangement is such that, in use, a thermal differential of at least 50° C. is established between the first and second electrodes (2 and 3), such that the second electrode is maintained below a temperature of 70° C.

Abstract: An electrosurgical system includes a generator for generating radio frequency (RF) power, and an electrosurgical instrument including at least three electrodes. The generator comprises an RF output stage having at least a pair of RF output lines, a power supply coupled to the output stage for supplying power to the output stage, and a controller capable of varying the RF power signal supplied to the output lines. The system also includes a selection circuit having at least three output connections each in electrical connection with a respective one of the at least three electrodes. This selection circuit operates to vary the coupling between the RF output stage and the three or more output connections.

Abstract: An electrosurgical system includes a generator for generating radio frequency power, and an electrosurgical instrument including at least three electrodes and. The generator includes a radio frequency output stage having at least a pair of RF output lines, and a power supply coupled to the output stage for supplying power to the output stage. A controller is operable to limit the radio frequency output voltage developed across the output lines to at least a first predetermined threshold value to produce a cutting RF waveform, and a second threshold value to produce a coagulating RF waveform. In a combined mode, the controller delivers both cutting and coagulating waveforms, either simultaneously or by alternating constantly between the first and second threshold values to form a blended signal.

Abstract: An electrosurgical system includes a generator for generating radio frequency (RF) power, and an electrosurgical instrument including at least three electrodes. The generator comprises an RF output stage having at least a pair of RF output lines, a power supply coupled to the output stage for supplying power to the output stage, and a controller capable of varying the RF power signal supplied to the output lines. The system also includes a selection circuit having at least three output connections each in electrical connection with a respective one of the at least three electrodes. This selection circuit operates to vary the coupling between the RF output stage and the three or more output connections.

Abstract: An electrosurgical cutting blade (1) comprises a first electrode (2), a second electrode (3), and an electrical insulator (4) separating the first and second electrodes. The first and second electrodes have dissimilar characteristics (cross-sectional area, thermal conductivity etc.) such that the first electrode (2) is encouraged to become an active electrode and the second electrode (3) is encouraged to become a return electrode. The spacing between the first and second electrodes (between 0.25 mm and 3.0 mm) and the peak voltage supplied to the electrodes (2 and 3) are both selected such that arcing does not occur directly between the electrodes, but between the first electrode and the tissue at the target site. The arrangement is such that, in use, a thermal differential of at least 50° C. is established between the first and second electrodes (2 and 3), such that the second electrode is maintained below a temperature of 70° C.