An electrosurgical apparatus and method for performing thermal treatment in the gastrointestinal tract, e.g. to ablate duodenal mucosal tissue. The apparatus comprises an instrument having a flexible cable and an applicator suitable for use with a gastroscope, which can be deployed within a patient to delivery energy in a targeted or otherwise controllable manner. The applicator can deliver microwave energy by radiation. The direct and depth-limited nature of microwave energy can be make it more effective than treatments that rely on thermal conduction. The applicator may include a radially extendable portion arranged to move an microwave energy delivery structure into contact with duodenal mucosal tissue at the treatment region. The applicator may comprise any of a balloon, bipolar radiator, movable paddle, and rotatable roller element.

An exemplary ablation system is provided. The system is designed for safe and efficacious energy delivery into tissue by, for example, emitting energy in a controlled, repeatable manner that allows for feedback and energy emission titration based on sensed parameters (e.g., tissue temperature) measured during ablation. The system may include a switching antenna for both heating of target tissue and radiometry to monitor the temperature of the heated tissue. For example, the switching antenna may include a monopole formed by proximal and distal radiating elements, such that the proximal radiating element includes a short to defeat a choke action of the proximal radiating element. The system further includes a processor for calculating the temperature of the target tissue and estimating volume of the ablation lesion based on the target tissue temperature.

An electrosurgical instrument for delivering microwave energy to biological tissue, in which a pair of conductive tuning elements are mounted in a radiating instrument tip to shape a microwave radiation profile of the instrument so that the radiation profile is constrained around the instrument tip. Such tuning elements may result in a radiation profile that is substantially spherical around the instrument tip, providing a well-defined ablation volume. The tuning elements act to improve the efficiency with which microwave energy can be delivered into target tissue.

Various high-strength microwave antenna assemblies are described herein. The microwave antenna has a radiating portion connected by a feedline to a power generating source, e.g., a generator. The antenna is a dipole antenna with the distal end of the radiating portion being tapered and terminating at a tip to allow for direct insertion into tissue. Antenna rigidity comes from placing distal and proximal radiating portions in a pre-stressed state, assembling them via threaded or overlapping joints, or fixedly attaching an inner conductor to the distal portion. The inner conductor is affixed to the distal portion by, e.g., welding, brazing, soldering, or by adhesives. A junction member made from a hard dielectric material, e.g., ceramic, can be placed between the two portions and can have uniform or non-uniform shapes to accommodate varying antenna designs. Electrical chokes may also be used to contain returning currents to the distal end of the antenna.

A device for directing energy to a target volume of tissue includes a monopole antenna assembly that includes a monopole antenna radiating section having a monopole antenna element surrounded by a dielectric material. The monopole antenna assembly also includes a ground plane disposed at a proximal end of the monopole antenna radiating section, wherein the ground plane is configured to direct energy into the target volume of tissue.

An antenna guide assembly including a guide body having a proximal end defining at least one proximal entry, a distal end defining at least one distal port, and at least one guide passage extending between the proximal and distal ends. The at least one guide passage is configured to receive at least a portion of an antenna therethrough via the at least one proximal entry such that a distal portion of the antenna extends through and distally from the at least one distal port for insertion into tissue. A locking assembly disposed at the distal end of the guide body is configured to receive the distal portion of the antenna therethrough. The locking assembly is configured to selectively engage the distal portion of the antenna to prevent translation of the antenna within the at least one guide passage.

A microwave ablation antenna assembly (20) incorporates a choke assembly (40) having a dielectric element (42) and a conducting element (48). The conducting element (48) is chosen from a group of elements of fixed length, but with differing electrical lengths for providing cancellation properties for different wavelengths of microwave energy.

The present invention discloses medical systems and methods adapted for the delivery of various medical components such as microwave antennas within or on a body for performing one or more medical procedures. Several embodiments herein disclose medical systems comprising a combination of one or more medical components and one or more elongate steerable or non-steerable arms that are adapted to mechanically manipulate the one or more medical components. Several embodiments of microwave antennas are disclosed that comprise an additional diagnostic or therapeutic modality located on or in the vicinity of the microwave antennas.

An ablation system including an image database storing a plurality of computed tomography (CT) images of a luminal network and a navigation system enabling, in combination with an endoscope and the CT images, navigation of a locatable guide and an extended working channel to a point of interest. The system further includes one or more fiducial markers, placed in proximity to the point of interest and a percutaneous microwave ablation device for applying energy to the point of interest.

A kit for delivering microwave ablative energy to tissue and methods for using the kit are included. The kit includes an access catheter, an implant deployment tool, and a microwave delivery device. The implant deployment tool is configured to be inserted into the access catheter and has an implant disposed therein in a contracted state and being slidable out of a distal opening and expandable into an expanded state. The microwave delivery device is configured to deliver the microwave ablative energy to the tissue and to be advanced through the access catheter and slidably disposable within the implant when the implant is in the expanded state.