251 results about "Microwave applicator" patented technology

Method and apparatus are provided for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue to treat ventricular tachycardia and other arrhythmias while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna (700) is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as antenna, frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In operation, microwave energy between about 1 Gigahertz and 12 Gigahertz is applied to monopole microwave radiator (600) having a surface wave limiter (606). A test setup provides physical testing of microwave radiators (854) to determine the temperature profile created in actual heart tissue or ersatz heart tissue (841). Saline solution (872) pumped over the heart tissue (841) with a peristaltic pump (862) simulates blood flow. Optical temperature sensors (838) disposed at various tissue depths within the heart tissue (841) detect the temperature profile without creating any electromagnetic interference. The method may be used to produce a desired temperature profile in other body tissues reachable by catheter (510) such as tumors and the like.

A minimally-invasive fluid-cooled insertion sleeve assembly, with an attached balloon and distally-located penetrating tip, into which sleeve any of a group comprising a rigid rod, a microwave-radiator assembly and an ultrasonic-imaging transducer assembly may be inserted, constitutes a probe of the system. The sleeve assembly comprises spaced inner and outer plastic tubes with two fluid channels situated within the coaxial lumen between the inner and outer tubes. The fluid coolant input flows through the fluid channels into the balloon, thereby inflating the balloon, and then exits through that coaxial lumen. An alternative embodiment has no balloon. The method employs the probe for piercing sub-cutaneous tissue and then ablating deep-seated tumor tissue with microwave-radiation generated heat.

A method for processing a dielectric film on a substrate comprises: depositing a porous dielectric film on a substrate; removing the porogen; stuffing the film with a protective polymeric material; performing at least one intermediate processing step on the stuffed dielectric film; placing the film in a microwave applicator cavity and heating to a first temperature to partially burn out the polymeric material; introducing a controlled amount of a polar solvent into the porosity created by the partial burn out; applying microwave energy to heat the film to a second selected temperature below the boiling point of the solvent to clean away remaining polymeric material; and applying microwave energy to heat the film to a third temperature above the boiling point of the solvent to completely burnout the residues of polymeric material. The interaction of the polar solvent with the microwaves enhances the efficiency of the cleaning process.

A microwave applicator for insertion into living body tissue for use in microwave coagulation and ablation treatments includes a microwave transmission line extending between an attachment end of the applicator and an antenna toward an insertion end of the applicator with an outer conductive sleeve forming an enclosed cooling fluid space around the transmission line. Circulation of cooling fluid is guided in the cooling fluid space by a guide sleeve. A temperature sensor senses the approximate temperature of cooling fluid to indicate cooling fluid is circulating. A multiplexing and power splitting circuit provides outputs tuned for one or for more than one applicator to be attached and detects the number of applicators and correct connection. A cadence sound generator can be used in conjunction with depth markings on the applicator to provide substantially constant withdrawal of the applicator from the treated tissue after treatment to provide track ablation.

A microwave thermokeratoplasty system uses an applicator having embedded sensors that provide feedback signals to a controller. The controller interprets these feedback signals to dynamically adjust or cease a keratoplasty operation. The system uses a microwave applicator that is specially adapted for direct application of energy to an eye in the course of treatment. The applicator is formed of discrete zones or sectors that are selectively controlled in an individual manner.

A microwave ablation probe for providing microwave energy to tissue is disclosed. The probe includes a feedline having an inner conductor, an insulating spacer and an outer conductor. The probe also includes a radiation portion having an extruded portion of the inner conductor that is centrally disposed therein. The radiation portion also includes one or more conductive disks disposed on the extruded portion of the inner conductor that defines one or more spaces and a dielectric material disposed within the spaces.

A method for processing a dielectric film on a substrate comprises: depositing a porous dielectric film on a substrate; removing the porogen; stuffing the film with a protective polymeric material; performing at least one intermediate processing step on the stuffed dielectric film; placing the film in a microwave applicator cavity and heating to a first temperature to partially burn out the polymeric material; introducing a controlled amount of a polar solvent into the porosity created by the partial burn out; applying microwave energy to heat the film to a second selected temperature below the boiling point of the solvent to clean away remaining polymeric material; and applying microwave energy to heat the film to a third temperature above the boiling point of the solvent to completely burnout the residues of polymeric material. The interaction of the polar solvent with the microwaves enhances the efficiency of the cleaning process.

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.