A microwave antenna has a radiating portion connected by a feedline to a power generating source, e.g., a generator. Proximal and distal radiating portions of the antenna assembly are separated by a junction member. A reinforcing member is disposed within the junction member to increase structural rigidity.

A circular microwave ablation antenna is provided with a chamber for accommodating the coaxial cable and the conduit, the chamber and the conduit extend forward to the front end of the antenna. An emission window of the antenna is at least partially located in the conduit to enable the cooling medium to cool the emission window area of the antenna. The conduit of the microwave emission area is made of an insulation material, so that the microwave can radiate outward, and the rest of the conduit is made of a microwave shielding material. The choke ring located at the rear side of emission area is hermetically fixed to the conduit, so that the choke ring acts to block the microwave. A gap exists between the choke ring and the needle bar, and the gap is used for the backflow of the cooling medium.

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 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.

A novel monitoring method evaluates tissue ablation progress. An antenna in a distal portion of an ablation applicator sends and receives electrical information from the target tissue during ablation. The information is used to determine ablation progress. A related ablation monitoring system includes a power monitor and processor operable to evaluate ablation progress based on reflected electrical properties during the ablation. The invention has particular benefits when used in endoscopic-based microwave ablation.

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.

Apparatus and systems of liquid metal-based tunable coaxial antenna for microwave ablation are described. Tunable antennas are capable of maintaining the optimal impedance matching in different organs of treatment as well as actively improving tissue heating during the course of the ablation. Efficient energy delivery to various tumor tissue and tissue conditions is critical in creating larger tumor margins and reducing the risk for local tumor progression. Efficient energy delivery can also help decrease the need for aggressive cooling mechanism from reflected power and antenna shaft heating. The tuning can be achieved by small physical motion of liquid metal plug actuated by pressure regulator.

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 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 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.