Abstract: An electrosurgical system has an electrosurgical generator with a multiple-phase RF output stage coupled to a multiple-electrode electrosurgical instrument. The instrument has three treatment electrodes each of which is coupled to a respective generator output driven from, for instance, a three-phase output transformer. Continuous RF output voltage waveforms are simultaneously delivered to respective generator outputs at the operating frequency, each waveform being phase-displaced with respect to the other waveforms. The magnitude of the RF output voltage waveform delivered to at least one of the generator outputs is sufficient to cause tissue vaporization at the respective treatment electrodes when the system is used for tissue treatment.

Abstract: An electrosurgical instrument includes a body portion, an actuator, a first jaw having a first electrode and a second jaw. The first electrode has a relatively large area seal surface with a relatively small edge portion and a third electrode, and the second jaw has a second electrode having a relatively large area seal surface and a smaller edge portion. The actuator moves the jaws between an first, open position, a second position for grasping tissue, and a third position where the jaws are further closed such that the first and second seal surfaces are adjacent each other and only the edge portions are exposed. An electrosurgical generator is connected to deliver a coagulation RF waveform between the first and second jaws when in the second position, and to deliver a cutting RF waveform between one or both of the first and second electrodes and the third electrode when the jaw members are in the third position.

Abstract: An electrosurgical system includes an electrosurgical generator including at least one source of radio frequency (RF) power, and a plurality of output connections, only one of the output connections at any one time being active in that it is able to receive radio frequency power from the source. The generator includes selection means adapted to change the active output connection, and a controller adapted to control the supply of radio frequency power from the source to the active output connection. The system also includes a plurality of electrosurgical assemblies, each including an electrosurgical instrument and a cable connecting the electrosurgical instrument to one of the output connections. The electrosurgical assemblies each include a handswitch adapted to send a signal to the selection means to change the active output connection.

Abstract: A device for morcellating tissue within a body cavity of a patient comprises a stationary tube having a distal end portion, and a bipolar electrosurgical electrode assembly located at the distal end of the tube. The electrosurgical electrode assembly comprises first and second electrodes separated by an insulation member, the bipolar electrosurgical electrode assembly extending around the circumference of the distal edge of the tube. When an electrosurgical cutting voltage is applied to the electrode assembly, and relative movement is initiated between the tube and the tissue, a core of severed tissue is formed within the tube such that it can be removed from the body cavity of the patient. A tissue-pulling device such as a jaw assembly can be employed to pull tissue against the distal end of the tube.

Abstract: A device for morcellating tissue within a body cavity of a patient comprises a stationary tube (8) having a distal end portion (12), and a bipolar electrosurgical electrode assembly (13) located at the distal end of the tube. The electrosurgical electrode assembly (13) comprises first and second electrodes (14, 16) separated by an insulating member (15), the bipolar electrosurgical electrode assembly extending around the circumference of the distal edge of the tube (8). When a pulsed electrosurgical cutting voltage is applied to the electrode assembly (13) and relative movement is initiated between the tube (8) and the tissue, a core of severed tissue is formed within the tube such that it can be removed from the body cavity of the patient. Temperature sensors (60) can be used to measure the temperature at the distal end of the tube (8), and to vary the duty cycle of the pulsed cutting voltage.

Abstract: An electrosurgical generator for coagulating tissue comprises a source of radio frequency (RF) energy, and at least a pair of output terminals for connection to a bipolar electrosurgical instrument adapted to contact tissue, the output terminals delivering RF energy from the source to the instrument such that the source delivers RF energy into tissue. The generator also includes boiling detection means for determining when the RF energy starts to cause the boiling of electrolytes within the tissue. A timer is adapted to determine when a predetermined period of time has elapsed since the boiling detection means has indicated the start of the boiling of electrolytes. An indication means gives an indication when the predetermined period of time has elapsed.

Abstract: An electrosurgical system for cutting and coagulating tissue includes a generator for generating radio frequency (RF) power, and an electrosurgical instrument. The instrument includes a pair of blades pivotally joined for relative movement in a scissors-like action between open and closed positions, each of said blades including a conductive blade member and a conductive electrode electrically isolated from the blade member by means of an insulation member. A first one of either the conductive blade member or the conductive electrode constitutes an inner electrode on each blade, which are disposed in face-to-face relationship. A second one of either the conductive blade member or the conductive electrode constitutes an outer electrode on each blade spaced from the inner electrode.

Abstract: An electrosurgical instrument comprises a body portion, an actuator mechanism associated with the body portion, and first and second jaw members each having a jaw body. The first jaw member includes a first electrode having a relatively large area conductive seal surface and a relatively smaller area edge portion. The second jaw member includes a second electrode also having a relatively large area conductive seal surface and a relatively smaller area edge portion. The first jaw member comprises a third electrode associated with its jaw body, and an insulator separating the first electrode from the third electrode.

Abstract: An electrosurgical system has an electrosurgical generator with a multiple-phase RF output stage coupled to a multiple-electrode electrosurgical instrument. The instrument has three treatment electrodes each of which is coupled to a respective generator output driven from, for instance, a three-phase output transformer. Continuous RF output voltage waveforms are simultaneously delivered to respective generator outputs at the operating frequency, each waveform being phase-displaced with respect to the other waveforms. The magnitude of the RF output voltage waveform delivered to at least one of the generator outputs is sufficient to cause tissue vaporisation at the respective treatment electrodes when the system is used for tissue treatment.

Abstract: An electrosurgical system includes an electrosurgical generator including at least one source of radio frequency (RF) power, and a plurality of output connections, only one of the output connections at any one time being active in that it is able to receive radio frequency power from the source. The generator includes selection means adapted to change the active output connection, and a controller adapted to control the supply of radio frequency power from the source to the active output connection. The system also includes a plurality of electrosurgical assemblies, each including an electrosurgical instrument and a cable connecting the electrosurgical instrument to one of the output connections. The electrosurgical assemblies each include a handswitch adapted to send a signal to the selection means to change the active output connection.

Abstract: Apparatus for forming a lesion in body tissue includes a probe having an active region with an electrode for contacting tissue to be treated, and an inactive region including an insulative sleeve around a portion of the electrode. The temperature of the inactive region is monitored using a temperature sensor. A controller supplies radio frequency energy to the electrode and samples signals from the temperature sensor. By performing a calculation using the sampled signals and a predetermined inactive region threshold temperature, and by adjusting the supplied radio frequency power, the inactive region of the probe can be maintained at or below an inactive region maximum temperature while the controller continues to supply radio frequency energy to the electrode. The probe has a second temperature sensor, mounted at a distal end of the electrode, the controller being configured to reduce the supplied radio frequency power when the electrode temperature reaches a predetermined maximum electrode temperature.

Abstract: In an electrosurgical generator for generating radio frequency power, the generator comprises a radio frequency output stage having three or more output connections, one or more sources of output power coupled to the output stage, and a controller operable to cause the generator to supply a first cutting RF waveform to the output connections or a second coagulating RF waveform to the output connections. In a combined mode, the controller causes the generator to deliver both first and second RF waveforms, the controller including means for feeding the waveforms to the output connections such that the first RF waveform is delivered between a first pair of the output connections, and the second RF waveform is delivered between a second pair of the output connections. The combined mode is adjustable between various settings, each setting having a different proportion of the first and second RF waveforms.

Abstract: An electrosurgery system includes an electrosurgical generator (10) coupled to or part of an electrosurgical instrument, the generator being operable to generate electrosurgical power in low frequency (typically at 1 MHz) and high frequency bands (typically at 2.45 GHz) either simultaneously or individually. The generator includes a load-responsive control circuit which, in one mode, causes power to be generated predominantly at 1 MHz when the load impedance is high and predominantly at 2.45 MHz when it is low. This allows automatic switching between cutting and coagulation operation. In one embodiment, the instrument includes a gas plasma generator operating such that an ionisable gas is energised in a gas supply passage by the 2.45 GHz component to form a plasma stream which acts as a conductor for delivering the 1 MHz component to a tissue treatment outlet of the passage.

Abstract: A device for morcellating tissue within a body cavity of a patient comprises a stationary tube (8) having a distal end portion (12), and a bipolar electrosurgical electrode assembly (13) located at the distal end of the tube. The electrosurgical electrode assembly (13) comprises first and second electrodes (14, 16) separated by an insulating member (15), the bipolar electrosurgical electrode assembly extending around the circumference of the distal edge of the tube (8). When a pulsed electrosurgical cutting voltage is applied to the electrode assembly (13) and relative movement is initiated between the tube (8) and the tissue, a core of severed tissue is formed within the tube such that it can be removed from the body cavity of the patient. Temperature sensors (60) can be used to measure the temperature at the distal end of the tube (8), and to vary the duty cycle of the pulsed cutting voltage.

Abstract: An electrosurgical generator for supplying RF power to an electrosurgical instrument for cutting or vaporising tissue has an RF output stage with RF output devices, a series-resonant output network and an RF output. The generator offers improved cutting and vaporising performance, especially in relation to the reliability with which an arc can be struck when presented with an initial load impedance load. This is achieved by virtue of the output stage being capable of maintaining output pulses of at least 1 kW peak by supplying the RF output devices from a large reservoir capacitor. An appropriate combination of cutting performance and haemostasis is provided by allowing for pulsed or continuous wave operation once an arc has been established, according to whether or not a surplus energy condition exists, as indicated by the voltage across the reservoir capacitor.

Abstract: An electrosurgical method and apparatus comprises a probe, at least one temperature sensor, and a controller for generating and controlling electromagnetic energy supplied to the probe. The controller receives signals from the temperature sensor and controls the supply of electromagnetic energy such that the temperature of the probe is ramped up and then maintained at a steady state temperature of between 100° C. and 115° C. In an equilibration phase, between the ramping up and the steady state temperature, the controller holds the temperature of the probe substantially constant for a period of time to allow the temperature of different parts of the probe to equilibrate.

Abstract: A device for morcellating tissue within a body cavity of a patient comprises a stationary tube having a distal end portion, and a bipolar electrosurgical electrode assembly located at the distal end of the tube. The electrosurgical electrode assembly comprises first and second electrodes separated by an insulation member, the bipolar electrosurgical electrode assembly extending around the circumference of the distal edge of the tube. When an electrosurgical cutting voltage is applied to the electrode assembly, and relative movement is initiated between the tube and the tissue, a core of severed tissue is formed within the tube such that it can be removed from the body cavity of the patient. A tissue-pulling device such as a jaw assembly can be employed to pull tissue against the distal end of the tube.

Abstract: A device for morcellating tissue within a body cavity of a patient comprises a stationary tube having a distal end portion, and a bipolar electrosurgical electrode assembly located at the distal end of the tube. The electrosurgical electrode assembly comprises first and second electrodes separated by an insulation member, the bipolar electrosurgical electrode assembly extending around the circumference of the distal edge of the tube. When an electrosurgical cutting voltage is applied to the electrode assembly, and relative movement is initiated between the tube and the tissue, a core of severed tissue is formed within the tube such that it can be removed from the body cavity of the patient. A tissue-pulling device such as a jaw assembly can be employed to pull tissue against the distal end of the tube.

Abstract: Apparatus for forming a lesion in body tissue includes a probe having an active region with an electrode for contacting tissue to be treated, and an inactive region including an insulative sleeve around a portion of the electrode. The temperature of the inactive region is monitored using a temperature sensor. A controller supplies radio frequency energy to the electrode and samples signals from the temperature sensor. By performing a calculation using the sampled signals and a predetermined inactive region threshold temperature, and by adjusting the supplied radio frequency power, the inactive region of the probe can be maintained at or below an inactive region maximum temperature whilst the controller continues to supply radio frequency energy to the electrode. The probe has a second temperature sensor, mounted at a distal end of the electrode, the controller being configured to reduce the supplied radio frequency power when the electrode temperature reaches a predetermined maximum electrode temperature.

Abstract: An electrosurgical generator for supplying RF power to an electrosurgical instrument for cutting or vaporising tissue has an RF output stage with RF output devices, a series-resonant output network and an RF output. The generator offers improved cutting and vaporising performance, especially in relation to the reliability with which an arc can be struck when presented with an initial load impedance load. This is achieved by virtue of the output stage being capable of maintaining output pulses of at least 1 kW peak by supplying the RF output devices from a large reservoir capacitor. An appropriate combination of cutting performance and haemostasis is provided by allowing for pulsed or continuous wave operation once an arc has been established, according to whether or not a surplus energy condition exists, as indicated by the voltage across the reservoir capacitor.