A current sensor includes a current sense coil disposed about a conductive lead, the current sense coil configured to sense a current passing through the conductive lead. The current sense coil includes: a first outer coil configured to detect a first magnetic field generated by the current; a second outer coil configured to detect the first magnetic field, the second outer coil further configured to cancel an electrical field induced in the first outer coil; and an inner conductor disposed between the first outer coil and the second outer coil, the inner conductor configured to detect a second magnetic field generated by the current.

A current sensor includes a current sense coil disposed about a conductive lead, the current sense coil configured to sense a current passing through the conductive lead. The current sense coil includes: a first outer coil configured to detect a first magnetic field generated by the current; a second outer coil configured to detect the first magnetic field, the second outer coil further configured to cancel an electrical field induced in the first outer coil; and an inner conductor disposed between the first outer coil and the second outer coil, the inner conductor configured to detect a second magnetic field generated by the current.

This invention relates to high-frequency ablation of tissue in the body using a cooled high-frequency electrode connected to a high frequency generator including a computer graphic control system and an automatic controller for control the signal output from the generator, and adapted to display on a real time graphic display a measured parameter related to the ablation process and visually monitor the variation of the parameter of the signal output that is controlled by the controller during the ablation process. In one example, one or more measured parameters are displayed simultaneously to visually interpret the relation of their variation and values. In one example, the displayed one or more parameters can be taken from the list of measured voltage, current, power, impedance, electrode temperature, and tissue temperature related to the ablation process. The graphic display gives the clinician an instantaneous and intuitive feeling for the dynamics and stability of the ablation process for safety and control. This invention relates to monitoring and controlling multiple ground pads to optimally carry return currents during high-frequency tissue ablation, and to prevent of ground-pad skin burns. This invention relates to the use of ultrasound imaging intraoperatively during a tissue ablation procedure. This invention relates to the use of nerve stimulation and blocking during a tissue ablation procedure.

An ultrasonic surgical tool system for actuating a handpiece with a tip. The frequency of the drive signal applied to the handpiece drivers is a function of the equivalent of current through the mechanical components of the handpiece and tip and the frequency responsiveness of these components.

Systems, such as an electrosurgical unit, and method for use with an active electrode and a plurality of return electrodes are disclosure. An electrosurgical treatment is provided to tissue via the active electrode at a treatment site and a first return electrode of the plurality of return electrodes at the treatment site. An impedance measurement is received or determined of an impedance in the tissue between the active electrode at the treatment site and a second return electrode of the plurality of return electrodes at a site remote from the treatment site.

A system comprising a generator which is capable of supplying energy for puncturing a tissue and an electrical current of known voltage, wherein the electrical current of known voltage can pass through the tissue without damaging the tissue. The system also includes a puncturing device comprising an elongate member. A distal tip of the elongate member comprises an energy delivery device which is configured for delivering the energy for puncturing and two electrodes which are configured for delivering the electrical current of known voltage from one electrode to the other through a material which is in contact with the distal tip. The system further includes a sensor which is capable of detecting a value of the electrical current between the two electrodes. The generator comprises a generator switch for disabling energy delivery tip based on the value of the electric current detected by the sensor.

An ultrasonic surgical tool system for actuating a handpiece with a tip. The frequency of the drive signal applied to the handpiece drivers is a function of the equivalent of current through the mechanical components of the handpiece and tip and the frequency responsiveness of these components.

This invention relates to high-frequency ablation of tissue in the body using a cooled high-frequency electrode connected to a high frequency generator including a computer graphic control system and an automatic controller for control the signal output from the generator, and adapted to display on a real time graphic display a measured parameter related to the ablation process and visually monitor the variation of the parameter of the signal output that is controlled by the controller during the ablation process. In one example, one or more measured parameters are displayed simultaneously to visually interpret the relation of their variation and values. In one example, the displayed one or more parameters can be taken from the list of measured voltage, current, power, impedance, electrode temperature, and tissue temperature related to the ablation process. The graphic display gives the clinician an instantaneous and intuitive feeling for the dynamics and stability of the ablation process for safety and control. This invention relates to monitoring and controlling multiple ground pads to optimally carry return currents during high-frequency tissue ablation, and to prevent of ground-pad skin burns. This invention relates to the use of ultrasound imaging intraoperatively during a tissue ablation procedure. This invention relates to the use of nerve stimulation and blocking during a tissue ablation procedure.

Systems, such as an electrosurgical unit, and method for use with an active electrode and a plurality of return electrodes are disclosure. An electrosurgical treatment is provided to tissue via the active electrode at a treatment site and a first return electrode of the plurality of return electrodes at the treatment site. An impedance measurement is received or determined of an impedance in the tissue between the active electrode at the treatment site and a second return electrode of the plurality of return electrodes at a site remote from the treatment site.

An electrosurgical generator supplies, during operation, a high-frequency alternating current to an electrosurgical instrument for plasma cutting of body tissue. The electrosurgical generator has outputs for connecting an electrosurgical instrument to supply an electrosurgical instrument connected to the outputs with a high-frequency alternating current, and for determining the impedance of a load connected to the outputs. The electrosurgical generator features impedance and voltage measuring units as well as an output voltage control unit. The output voltage control unit is designed to control the AC output voltage depending on a maximum output voltage value that is set during operation depending on an output value of the impedance measuring unit and/or depending on an output value of the voltage measuring unit, such that the maximum output voltage value predefines a lower AC output voltage during a vaporization phase than during an ignition phase occurring subsequently to the vaporization phase.