1433results about How to "High impedance" patented technology

An electrosurgical system comprises a radio frequency generator (1), an electrosurgical instrument (E1), and a fluid enclosure (42). The generator (1) has a radio frequency output for delivery of power to the electrosurgical instrument (E1) when immersed in an electrically-conductive fluid. The electrosurgical instrument (E1) has an electrode assembly (32) at the distal end thereof, the electrode assembly comprising a tissue treatment electrode (34), and a return electrode (38) axially spaced therefrom in such a manner as to define, in use, a conductive fluid path that completes an electrical circuit between the tissue treatment electrode and the return electrode. The fluid enclosure (42) is adapted to surround an operation site on the skin of a patient or an incision leading to a cavity surgically created within the patient's body. The fluid enclosure (42) includes sealing means (44) for sealing against the patient's tissue, and the fluid enclosure includes at least one port (50a, 52a) through which the electrosurgical (E1) is insertable, and through which the electrically-conductive fluid can enter and / or leave the enclosure. The fluid enclosure device of the present invention can also be used to treat tumours within the colon. The enclosure, which includes a proximal and a distal bung, is inserted into the colon in a deflated condition and then inflated with a conductive fluid or gas. The colon can be supported against the pressure of the fluid or gas with a pressure sleeve that has been inserted to surround the region of the colon being treated. An electrosurgical instrument is then inserted into the colon and manipulated to vaporize the tumor.

A method is disclosed for treating benign conditions, such as enlarged tonsils and / or adenoids located in a patient's throat or nasopharynx, or soft tissue lesions located in a patient's oropharynx or larynx. According to the method, a space containing the patient's nasopharynx, oropharynx or pharynx and larynx is isolated from the patient's trachea and lungs using an inflatable cuff tracheostomy tube or nasotracheal tube inserted in the patient's trachea. The cuff is inflated to occlude the trachea. The patient is placed in a supine position, whereupon at least a portion of the space containing the nasopharynx and / or oropharynx and larynx is filled with saline. An endoscope is then inserted into the space to view the operative site in which the tonsils or tissue lesion are to be treated. An electrosurgical instrument having an active tissue treatment electrode and a return electrode connected to an electrosurgical generator is then inserted into the space, either along side the endoscope or through the endoscope's working channel. The generator is then operated to apply a radio frequency voltage between the active and return electrodes of the electrosurgical instrument, whereby a conduction path is formed between the active and return electrodes, at least partially through the saline, whereupon the active electrode is manipulated to debulk or otherwise treat the soft tissue lesion or enlarged tonsils and / or adenoids.

A device for monitoring a rotating shaft is provided. The device measures strain in the shaft and provides angular velocity and torque in the shaft. The device includes a sensor, sensor conditioning circuitry, a microprocessor, and a transmitter, all located on a rotating shaft. The device obtains power by harvesting mechanical energy of the rotating shaft itself. Coils are provided rotating with the shaft and permanent magnets are mounted adjacent the rotating shaft so electrical energy is induced in the coils as they rotate through the magnetic field of the permanent magnets. A battery or capacitor is connected to the coils for storing energy. A microprocessor is connected to the sensors, the storage device, and the transmitter for managing power consumption and for monitoring the amount of electrical energy stored in the storage device and for switchably connecting the storage device to the transmitter when the stored energy exceeds a threshold.

Medical apparatus includes a pacing generator, which has first active and indifferent outputs and is configured to generate electrical pacing pulses between the first active and indifferent outputs for pacing a heart of a subject. A radio frequency (RF) generator has second active and indifferent outputs and is configured to generate RF electrical energy of a predetermined frequency between the second active and indifferent outputs for application to the heart of the subject simultaneously with the pacing pulses. A filter includes a first branch connected between the first and second active outputs and a second branch connected between the first and second indifferent outputs, each of the first and second branches including one or more notch filters having a high impedance in a vicinity of the frequency of the RF electrical energy.

An electronic disabling device includes first and second electrodes positionable to establish first and second spaced apart contact points on a target having a high impedance air gap existing between at least one of the electrodes and the target. The power supply generates a first high voltage, short duration output across the first and second electrodes during a first time interval to ionize air within the air gap to thereby reduce the high impedance across the air gap to a lower impedance to enable current flow across the air gap at a lower voltage level. The power supply next generates a second lower voltage, longer duration output across the first and second electrodes during a second time interval to maintain the current flow across the first and second electrodes and between the first and second contact points on the target to enable the current flow through the target to cause involuntary muscle contractions to thereby immobilize the target.

A method for measuring a neural response to a stimulus. Measurement circuitry is settled prior to a stimulus, by connecting a sense electrode to the measurement circuitry to allow the measurement circuitry to settle towards a bio-electrically defined steady state. Charge is recovered on stimulus electrodes by short circuiting the stimulus electrodes to each other. An electrical stimulus is then applied from the stimulus electrodes to neural tissue, while keeping the sense electrode disconnected from the measurement circuitry. After the stimulus, a delay is imposed during which the stimulus electrodes are open circuited and the sense electrode is disconnected from the measurement circuitry and from the stimulus electrodes. After the delay, a neural response signal present at the sense electrode is measured by connecting the sense electrode to the measurement circuitry.

A surge protection device is disclosed that includes an input path for receiving an rf signal, dc power, and a surge, an output path for propagating the rf signal, and a dc blocking device coupled in series between the input path and the output path. The surge protection device also includes a first inductor coupled to the input path for isolating the rf signal and providing a path for the dc power, a gas tube coupled to the first inductor for routing a portion of the surge to a ground plane, a second inductor coupled to the first inductor for providing a path for the dc power, and a metal oxide varistor coupled to the second inductor for routing a portion of the surge to the ground plane. Furthermore, the surge protection device includes a third inductor coupled to the second inductor for providing a path for the dc power, a diode coupled to the third inductor for routing a portion of the surge to the ground plane, and a fourth inductor coupled to the third inductor for providing a path for the dc power to the output path.

A backplane for an electro-optic display comprises a pixel electrode (104), a voltage supply line (C) arranged to supply a voltage to the pixel electrode (104), and a micromechanical switch (106, 112) disposed between the voltage supply line (C) and the pixel electrode (104), the micromechanical switch (106, 112) having an open state, in which the voltage supply line (C) is not electrically connected to the pixel electrode (104), and a closed state, in which the voltage supply line (C) is electrically connected to the pixel electrode (104).

A device for powering a load from an ambient source of energy is provided. The device includes an energy harvesting device for harvesting energy from the ambient source of energy wherein the rate energy is harvested from the ambient source of energy is below that required for directly powering the load. A storage device is connected to the energy harvesting device. The storage device receives electrical energy from the energy harvesting device and is for storing the electrical energy. A controller is connected to the storage device for monitoring the amount of electrical energy stored in the storage device and for switchably connecting the storage device to the load when the stored energy exceeds a first threshold. The system can be used for powering a sensor and for transmitting sensor data, such as tire pressure.