Abstract: An isolating circuit for electrosurgical generator arranged to produce radiofrequency (RF) energy and microwave energy for treating biological tissue. The generator has an RF channel and a microwave channel which are combined at signal combiner to enable the RF energy and microwave energy to be delivered into tissue along a common feed path. The isolating circuit comprises a tunable waveguide isolator at a junction between the microwave channel and signal combiner, and can include a capacitive structure between a ground conductor of the signal combiner and a conductive input section of the waveguide isolator to inhibit coupling of the RF energy and leakage of the microwave energy. The isolating circuit can combine into a single tunable unit all the necessary components to isolate the microwave and RF channels from one another whilst providing a high withstanding voltage.

Abstract: An electrosurgical instrument which is capable of selective operation in any of (i) a plasma-generating mode for surface coagulation, (ii) a non-ionising radiation mode for deeper coagulation, e.g. using microwave energy, and (iii) a liquid administration mode for conveying liquid to a treatment site, e.g. to constrict a bleeding vessel so that a clinician can get control of the bleed. These operating modes may be provided in an electrosurgical instrument that is physically configured to be suitable for applying pressure to a tissue vessel, e.g. to act as a tamponade to stem bleeding.

Abstract: A helical antenna structure for use in an electrosurgical instrument. The helical antenna structure is connectable to inner and outer conductors of a coaxial transmission line, and can act as both a radiating antenna or applicator structure, and also in a mode where an electric field is generated between its electrodes. In this way, the helical antenna structure may be used both for argon plasma coagulation, and deep tissue coagulation, as well as providing means for delivering a fluid, e.g. a therapeutic fluid such as adrenaline. This may be achieved through the use of helically arranged electrodes and a channel for gas to flow. This device is also used to deliver adrenaline and RF/microwave energy.

Abstract: An electrosurgical instrument for use in minimally invasive surgical techniques that provides a small scale localized microwave field capable of precisely ablating tissue, e.g. in the lungs, through suitable selection of geometry and material for a radiating distal tip thereof. The instrument may be used with a bronchoscope having a power delivery structure formed within the instrument cord thereof. A vision system may be incorporated into the energy delivery structure. The instrument comprise a coaxial cable for conveying microwave energy to a radiating tip portion that comprises a dielectric tip and a distal conductive portion that extends longitudinally therein. The dielectric tip has a dielectric constant greater than a dielectric material within the coaxial cable. The distal end of the device is designed to facilitate efficient microwave energy delivery into lung tumour tissue to achieve a localized volume of ablation.

Abstract: An energy delivery system for performing tissue ablation at the distal end of an Electromagnetic Navigation Bronchoscopy (ENB) instrument. The system is insertable through an instrument channel of a steerable instrument cord in an ENB instrument, and comprise a coaxial cable with a radiating tip portion. The tip portion comprises a first conductive element electrically connected to the coaxial cable's inner conductor and a second conductive element electrically isolated from the inner conductor. The conductive elements are arranged to act as: an active electrode and a return electrode for delivering the RF energy into tissue surrounding the radiating tip portion, and an antenna for radiating the microwave energy as a localized microwave field. The system may be arranged to delivery energy according to a predetermined profile comprising interleaving periods of RF and microwave energy or a combination thereof, or a dynamic profile based on detected tissue impedance.

Abstract: An isolating circuit for an electrosurgical generator arranged to produce radiofrequency (RF) energy and microwave energy for treating biological tissues is provided. The generator has an RF channel and a microwave channel which are combined at a signal combiner to enable the RF energy and microwave energy to be delivered into tissues along a common feed path. The isolating circuit includes a tunable wavelength isolator at a junction between the microwave channel and the signal combiner, and can include a capacitive structure between a ground conductor of the signal combiner and a conductive input section of the waveguide isolator to inhibit coupling of the RF energy and leakage of the microwave energy. The isolating circuit can combine into a single tunable unit all the necessary components to isolate the microwave and RF channels from one another while providing a high withstanding voltage.

Abstract: An electrosurgical apparatus having a feed structure comprising a radiofrequency (RF) channel for conveying RF electromagnetic (EM) radiation from an RF signal generator to a probe and a microwave channel for conveying microwave EM radiation from a microwave signal generator to the probe, wherein the RF channel and microwave channel comprise physically separate signal pathways, wherein the feed structure includes a combining circuit having an input connected to the signal pathway on the RF channel, another input connected to the signal pathway on the microwave channel, and an output connected to a common signal pathway for conveying the RE EM radiation and EM radiation separately or simultaneously to the probe, and wherein the microwave channel includes a waveguide isolator connected to isolate the signal pathway on the microwave channel from the RF EM radiation.

Abstract: A surgical spatula has a planar transmission line for carrying microwave energy formed from a sheet of a first dielectric material which has first and second conductive layers on opposite sides thereof. The surgical spatula also has a coaxial cable for delivering microwave energy to the planar transmission line. The coaxial cable has an inner conductor, an outer conductor coaxial with the inner conductor and a second dielectric material separating the inner and outer conductors. The inner and outer conductors extend beyond the second dielectric to overlap opposite surfaces of the transmission line and electrically contact the first conductive layer and second conductive layer respectively. The width of the first and second conductive layers is selected to create an impedance match between the transmission line and the coaxial cable.

Abstract: Sterilization apparatus comprising a sterilization instrument configured to be inserted through the instrument channel of a surgical scoping device and a withdrawal device for withdrawing the sterilization instrument from the instrument channel at a predetermined rate. The sterilization instrument comprises an elongate probe having a probe tip with a first electrode and a second electrode arranged to produce an electric field from received RF and/or microwave frequency EM energy. In operation the instrument may disinfect an inner surface of the instrument channel by emitting energy whilst being withdrawn through the channel.

Abstract: An electrosurgical device capable of both: (i) generating a radiative microwave field to perform either blood coagulation or sterilization, and (ii) dispensing a liquid to a target area, e.g. adrenaline for the treatment of peptic ulcers. Using microwave energy allows controlled coagulation which is unaffected by changes in tissue impedance during coagulation, and which can achieve a high level of coagulation within a given time. The device comprises a probe tip having a coaxial transmission line that includes a hollow inner conductor having a dielectric material formed on an inner surface thereof. A liquid-conveying channel is located inside the dielectric material. The probe tip includes a conductive element coupled to receive microwave energy from the, coaxial transmission line, the conductive element forming a radiating antenna structure for emitting a microwave EM field outwardly from the probe tip.

Abstract: An electrosurgical instrument for delivering radiofrequency (RF) electromagnetic (EM) energy and microwave frequency EM energy from a coaxial feed cable through an instrument tip into tissue. The instrument tip comprises a dielectric body separating first and second conductive elements, which act as active and return electrodes to convey the RF EM radiation by conduction, and as an antenna to radiate the microwave EM radiation. The instrument also has a fluid feed incorporated into its tip, e.g. in an additional dielectric element mounted on the underside of the tip, for delivering fluid. The delivered fluid may be a gas plasma to assist treatment or a liquid to plump up a tissue region before treatment. The instrument may fit in an endoscope.

Abstract: An electrosurgical vessel sealing device that can seal biological vessels using a confined microwave field that yields a well-defined seal location with low thermal margin. The device comprises a pair of jaws that are movable relative to each other to grip biological tissue. A blade for cutting the gripped tissue is slidable between the jaws. A coplanar microstrip antenna is mounted on the inner surface of one or both of the pair of jaws to emit microwave energy into the gap therebetween. The device may comprise a separate dissector element to enable fine tissue cutting and dissection to be performed.

Abstract: An electrosurgical apparatus having a feed structure comprising a radiofrequency (RF) channel for conveying RF electromagnetic (EM) radiation from an RF signal generator to a probe and a microwave channel for conveying microwave EM radiation from a microwave signal generator to the probe, wherein the RF channel and microwave channel comprise physically separate signal pathways, wherein the feed structure includes a combining circuit having an input connected to the signal pathway on the RF channel, another input connected to the signal pathway on the microwave channel, and an output connected to a common signal pathway for conveying the RE EM radiation and EM radiation separately or simultaneously to the probe, and wherein the microwave channel includes a waveguide isolator connected to isolate the signal pathway on the microwave channel from the RF EM radiation.

Abstract: The disclosure relates to three enhancements for a surgical snare: an electrosurgical snare in which the loop of snare wire extends from an energy transfer surface which can act both as a physical reaction surface for mechanical cutting using the snare and as a region for emitting electromagnetic energy; a surgical snare having a snare wire having a first end connected to a movable boss that is slidably mounted on a coaxial cable; and a surgical snare having an end cap with a distally facing reaction surface and a pair of channels for guiding a snare wire, where the distally facing reaction surface is arranged to contact the retractable loop when fully retracted.

Abstract: An electrosurgical instrument for delivering microwave energy having a predetermined frequency into biological tissue in contact with the instrument, wherein the instrument comprises a first coaxial transmission line having a second coaxial transmission line connected to the distal end thereof, the second coaxial transmission line having a length and a characteristic impedance that are configured to match the impedance of the first coaxial transmission line to the load impedance at the distal end of the distal coaxial transmission line when the instrument is in contact with the tissue, at the operating frequency.

Abstract: Embodiments of the invention provide a hollow cable for transmitting radiofrequency and/or microwave frequency energy to an electrosurgical instrument, wherein the hollow cable is provided with electrical connectors for forming a bipolar electrical connection with an electrosurgical instrument that fits within, e.g. slides relative to, the hollow cable. The connectors can be conductive protrusions extending in an axial direction on opposite sides of the cable. The protrusions can be tabs, fins, rods, pins, or wires. The protrusions can be strips which engage corresponding terminals on the instrument. The transmission line structure of the invention can have a greater diameter than conventional coaxial cables, which can minimize loss whilst still providing access for control wires and/or fluid to reach a surgical instrument. The cable can be used with multiple instruments.

Abstract: Embodiments of the invention provide a hollow cable for conveying radiofrequency and/or microwave frequency energy to an electrosurgical instrument that can fit within, e.g. slide relative to, the hollow cable. The hollow cable provides a bipolar electrical connection to the electrosurgical instrument that is maintained when the electrosurgical instrument is rotated relative to the hollow cable. The cable may comprise a hollow coaxial transmission line having a rotatable component mounted at its distal end. The rotatable component comprises a longitudinal passageway continuous with the hollow coaxial transmission line. The rotatable component is rotatable relative to the transmission line and comprises a first and second conductive portions that are respectively electrically connected to first and second terminals on the coaxial transmission line and which are configured to maintain an electrical connection with their respective terminal when rotated relative to the coaxial transmission line.

Abstract: Surgical cutting apparatus having a treatment channel and a measurement channel for conveying microwave energy from a source to an antenna at a cutting edge. The measurement channel operates at lower power than the treatment channel for determining when higher energy can be safely applied. The apparatus may deliver microwave radiation at differing frequencies to one or more antennas at the cutting edge, e.g. to provide different treatment effects. The source may generate an output for an antenna whose frequency can be selected e.g. for most efficient operation. Selection may be automatic based on detected magnitude and phase of reflected signals during a frequency sweep of a forward signal. Power delivered to tissue via the cutting element may be manually boosted to deal with large blood vessels. The apparatus may include a reflected power monitor for recognising behaviour in reflected signals received from the antenna to trigger automatic pre-emptive action.

Abstract: Embodiments of the invention provide a surgical snare structure in which the material used for the snare and the deployment mechanism of the snare are configured to improve the cutting efficacy of the snare. In particular, the surgical snare structure of the invention may omit the kink or nib present in the loop of known surgical snares and/or may provide a reaction surface against which the cutting action of the snare is effective. The surgical snare of the invention may be a cold, i.e. mechanical-only effect, snare, or may be used in conjunction with radiofrequency (RF) and/or microwave energy to enhance a cutting or coagulation effect.

Abstract: A sterilization system having a controllable non-ironing microwave radiation source for providing microwave energy for combining with a gas to produce atmospheric low temperature plasma for sterilizing biological tissue surfaces or the like. A plasma generating region may be contained in a hand held plasma applicator. The system may include an impedance adjustor e.g. integrated in the plasma applicator arranged to set a plasma strike condition and plasma sustain condition. The gas and microwave energy may be transported to a plasma generating region along an integrated cable assembly. The integrated cable assembly may provide a two way gas flow arrangement to permit residual gas to be removed from the surface. Invasive surface plasma treatment is therefore possible. The plasma applicator may have multiple plasma emitters to produce a line or blanket of plasma.