Abstract: A microwave applicator comprising a coaxial electrical input (4) and a waveguide (1) filled with dielectric (2), an inner conductor (7) of the coaxial input extending longitudinally within one end of the waveguide to launch microwaves in the TM01 mode to travel to the distal end face (8) of the waveguide so that microwaves are transmitted when the distal end face is contacted by the biological tissue to be treated.

Abstract: A microwave applicator has a coaxial electrical input (4) and a waveguide (1) filled with dielectric (2), an inner conductor (7) of the coaxial input extending longitudinally within one end of the waveguide to launch microwaves in the TM01 mode to travel to the distal end face (8) of the waveguide so that microwaves are transmitted when the distal end face is contacted by the biological tissue to be treated.

Abstract: A radiation applicator with a dielectric body (2) surrounding the antenna. The dielectric body (2) is comprised of three sections (3, 4 and 5) with different dielectric constants to provide broad-band matching of the applicator to surrounding material. Washers (10) and (11) are mounted on the antenna to act as reflectors.

Abstract: A microwave applicator device comprising a probe (11) for ablating the body of a human or animal, a cooling passage sage (20, 21) extending through the probe (11) and arranged to carry a cooling fluid, a pump (71) for pumping the fluid through the probe (11), and an elongate flexible duct (104) extending between the pump (71) and one end of the cooling passage (20, 21), the pump comprising a pump body (73) including a motor (120) and a pump head (72) detachably mounted to the pump body (73), the pump head (72) comprising a first port (86) connected to a proximal end of the elongate flow duct (104), a second port (85) and fluid propulsion means (84, 92) for creating a flow of fluid between the ports (85, 86) and along the elongate flow duct 104 upon energisation of the motor (120), the pump head (72) being arranged to sealingly contain the fluid.

Abstract: This invention provides an elongate microwave radiator for insertion into a living body to treat tissue at a predetermined operating frequency. The radiator defines a monopole antenna at its tip. The monopole antenna includes a dielectric material surrounding the monopole. The dielectric material is configured to act as a resonator at the predetermined operating frequency, and encompasses generally the whole of a near-field radiation emitted by the monopole. In an illustrative embodiment, the dielectric material extends from the antenna a distance determined in accordance with the wavelength of the radiation in the dielectric.

Abstract: This invention provides an elongate microwave radiator for insertion into a living body to treat tissue at a predetermined operating frequency. The radiator defines a monopole antenna at its tip. The monopole antenna includes a dielectric material surrounding the monopole. The dielectric material is configured to act as a resonator at the predetermined operating frequency, and encompasses generally the whole of a near-field radiation emitted by the monopole. In an illustrative embodiment, the dielectric material extends from the antenna a distance determined in accordance with the wavelength of the radiation in the dielectric.

Abstract: A microwave applicator having a probe which comprises an elongate shaft (14), the shaft having an external tubular wall (18), a radiating portion (15) disposed at the distal end of the shaft (14), a transmission line (17) extending to the radiating portion internally of the tubular external wall (18), and an elongate flow dividing member (19) which co-extends with the transmission line (17) longitudinally of the shaft (14), the side wall of the transmission line (17) and the side wall of the flow dividing member (19) contacting each other and contacting the internal surface of the external tubular wall (18) at two-spatially separated discrete positions, thereby defining a pair of flow channels (20, 21) inside the shaft (14). In use, cooling fluid can pass down one channel (20) and return via the other channel (21). The structure of the probe is uncomplicated and the probe is straightforward to assemble.

Abstract: This invention provides an elongate microwave radiator for insertion into a living body to treat tissue at a predetermined operating frequency. The radiator defines a monopole antenna at its tip. The monopole antenna includes a dielectric material surrounding the monopole. The dielectric material is configured to act as a resonator at the predetermined operating frequency, and encompasses generally the whole of a near-field radiation emitted by the monopole. In an illustrative embodiment, the dielectric material extends from the antenna a distance determined in accordance with the wavelength of the radiation in the dielectric.

Abstract: A microwave applicator comprising a coaxial electrical input (4) and a waveguide (1) filled with dielectric (2), an inner conductor (7) of the coaxial input extending longitudinally within one end of the waveguide to launch microwaves in the TM01 mode to travel to the distal end face (8) of the waveguide so that microwaves are transmitted when the distal end face is contacted by the biological tissue to be treated.

Abstract: A dipole microwave applicator emits microwave radiation into tissue to be treated. The applicator is formed from a thin coax cable having an inner conductor surrounded by an insulator, which is surrounded by an outer conductor. A portion of the inner conductor extends beyond the insulator and the outer conductor. A ferrule at the end of the outer conductor has a step and a sleeve that surrounds a portion of the extended inner conductor. A tuning washer is attached to the end of the extended inner conductor. A dielectric tip encloses the tuning washer, the extended inner conductor, and the sleeve of the ferrule. The sleeve of the ferrule and the extended inner conductor operate as the two arms of the dipole microwave antenna. The tuning washer faces the step in the ferrule, and is sized and shaped to cooperate with the step in balancing and tuning the applicator.

Abstract: A radiation applicator (102) for applying electromagnetic radiation to tissue, comprising: an axial central conductor (124) adapted to be coupled to a source of electromagnetic radiation and defining an axis; an elongate dielectric member (126), the dielectric member surrounding at least part of said central conductor along an axial length thereof, a metal ferrule (106), the ferrule being attached to the dielectric member and surrounding a portion of the central conductor and extending parallel thereto along a length thereof. The ferrule and the dielectric member have respective elongate cooperating surfaces and wherein the ferrule and the dielectric member are fixed to each other with said cooperating surfaces in close abutment, thereby providing a rigid structure.

Abstract: A microwave applicator (2) which comprises an antenna (10) for transmitting microwaves. Electrically conductive pins (24) such as metallic pins are present near the antenna in order to create regions (26) of low or substantially null magnetic field in the magnetic field surrounding the antenna. A sensor such as a thermocouple can be placed in one of the regions, and the effects of the magnetic field on the sensor are reduced or substantially eliminated.

Abstract: A dipole microwave applicator emits microwave radiation into tissue to be treated. The applicator is formed from a thin coax cable having an inner conductor surrounded by an insulator, which is surrounded by an outer conductor. A portion of the inner conductor extends beyond the insulator and the outer conductor. A ferrule at the end of the outer conductor has a step and a sleeve that surrounds a portion of the extended inner conductor. A tuning washer is attached to the end of the extended inner conductor. A dielectric tip encloses the tuning washer, the extended inner conductor, and the sleeve of the ferrule. The sleeve of the ferrule and the extended inner conductor operate as the two arms of the dipole microwave antenna. The tuning washer faces the step in the ferrule, and is sized and shaped to cooperate with the step in balancing and tuning the applicator.

Abstract: A method of treating hollow anatomical structures, for example varicose veins. The method comprises: providing an elongate radiation applicator, the elongate applicator including an emitter, the emitter being coupled to a source of microwave radiation and being adapted to emit said radiation; introducing the applicator into a hollow anatomical structure, the hollow anatomical structure including a section of target tissue; traversing the applicator past the section of target tissue while said emitter emits microwave radiation of a predetermined intensity into said section. Techniques are used (markings on the coaxial cable in conjunction with an audible tone) so that the user makes the traversal at a predetermined rate so that uniform application of the radiation to the tissue, and effective occlusion, occurs. An applicator for performing the treatment is also disclosed.

Abstract: A radiation applicator with a dielectric body (2) surrounding the antenna The dielectric body (2) is comprised of three sections (3, 4 and 5) with different dielectric constants to provide broad-band matching of the applicator to surrounding material. Washers (10) and (11) are mounted on the antenna to act as reflectors.

Abstract: This invention provides an elongate microwave radiator for insertion into a living body to treat tissue at a predetermined operating frequency. The radiator defines a monopole antenna at its tip. The monopole antenna includes a dielectric material surrounding the monopole. The dielectric material is configured to act as a resonator at the predetermined operating frequency, and encompasses generally the whole of a near-field radiation emitted by the monopole. In an illustrative embodiment, the dielectric material extends from the antenna a distance determined in accordance with the wavelength of the radiation in the dielectric.

Abstract: Radiation applicators comprise an elongate device having an antenna (240, 340) at their tip for coupling radiation into biological tissue and a dielectric body (250, 350) surrounding the antenna so as to encompass substantially the whole of the near-field region of the antenna and/or to enhance transmission of radiation in the forward direction. The body (250, 350) may be cylindrical with the antenna (240, 340) along its axis. The antenna may be ?/2 in length and ?/2 in radius. The tip (270) of the antenna (240) may be rounded hemispherical with radius ?/2 to enhance forward transmission of radiation. The dielectric constant (?) of the body (250, 350) is as high as possible to reduce its diameter at a desired operating frequency but may be matched to the surrounding tissue by another layer of dielectric material (380) with a value (?) intermediate that of the core (360) of the body (350) and the tissue.