An endoscopic treatment tool comprises an elongated sheath and an elongated portion configured to be inserted in the elongated sheath and capable of being movable back and forth in directions. A loop portion is disposed on a distal end of the elongated portion and is constructed of a wire folded to form into a loop. The loop portion includes a first bent portion, a pair of second bent portions, a pair of third bent portions, and a fourth bent portion all of which are integrally formed from a distal end toward a proximal end of the loop portion. A first length that represents a length from the first bent portion to the fourth bent portion in the directions along the longitudinal axis ranges from one and half times to two times a first width that represents a maximum dimension of the loop portion in directions perpendicular to the longitudinal axis.

A controller for an electrosurgical device and related methods and devices are disclosed. The controller has a processing component to: (a) derive a power factor of power applied to the electrosurgical device; and (b) responsive to the deriving a power factor, assign a circuit status to a circuit comprising the electrosurgical device. IF (PF0) and ((Vrms/Irms)T), THEN the circuit status is open. IF (PF0) and ((Vrms/Irms)<T), THEN the circuit status is short. PF is the power factor. Vrms is the root mean square of a voltage associated with the power applied to the at electrosurgical device. Irms is the root mean square of a current associated with the power applied to the electrosurgical device. T is a threshold value.

Polypectomy devices and methods for making and using polypectomy devices are disclosed. An example polypectomy device may include an elongate sheath having a proximal end region and a distal end region. A shaft may be slidably disposed within the sheath. A handle may be coupled to the proximal end region of the sheath. The handle may be designed to axially shift the shaft relative to the sheath. A snare may be coupled to the shaft. The snare may include a first region, a traction region, and a distal tip region. The first region may have a non-circular cross-sectional shape. The traction region may include a plurality of traction members. At a position between two adjacent traction members the snare may have a reduced cross-sectional area relative to the first region. The distal tip region may have a circular cross-sectional shape.

An electrosurgical snare, e.g. suitably sized for insertion down the instrument channel of an endoscope, arranged to radiate microwave frequency energy (e.g. having a frequency greater than 1 GHz) from an elongate conductive element within an area encircled by a retractable loop. The elongate conductive element and retractable loop may be independently slidable relative to a snare base at a distal end of a sleeve to provide an appropriate device configuration. By controlling the shape of the emitted microwave field, the risk of collateral thermal damage can be reduced.

An electrosurgical snare device is provided which uses a flow of inert gas to assist in the cutting and sealing process of tissue, while substantially reducing the formation of eschar and collateral tissue damage. The electrosurgical device includes a housing having a longitudinal axis; a support shaft attached to a distal end of the housing, and an end effector coupled to a distal end of the support shaft. The end effector includes a tube including a plurality of apertures and an electrically conducting spring disposed around the tube, where a spacing of the coils of the spring coincides with a spacing of the plurality of apertures, wherein a gas assisted electrosurgical effect is formed at each of the plurality of apertures when an inert gas flows through the tube and the spring is energized. The tube may be configured as a loop or snare.

A surgical snare comprising a means of delivering thermal plasma on to biological tissue encircled by the snare. The snare may be cold snare, i.e. formed from insulating material, or active, i.e. connected to receive RF and/or microwave energy to be radiated into the area encircled by the snare. The surgical snare may thus deliver into biological tissue encircled by a retractable loop any one of (i) a plasma to perform surface coagulation, (ii) a non-ionising microwave field (in the absence of plasma) to perform coagulation at a deeper level, and (iii) an RF field to assist with cutting.

Systems, methods and devices for performing water aided endoscopy (WAE) are provided herein. The systems include a plurality of devices designed to create a sealed environment within the body cavity, including a multi-functional plug, valves, balloons and pumps. The systems also provide specialized tools configured for operation within a liquid environment which are designed to interface with the multi-functional seal for insertion into the body cavity while maintaining the seal, including an adjustable constant shape snare. Additional features of the systems and methods include specialized fluids for increasing visibility with the body cavity, dyes and other solutions for image-enhancement and diagnostics, and software for increasing the clarity of the image in real-time.

A handle assembly includes a drive wire coupled to an expandable end effector, the wire having a diameter of no more than 3 French and a handle cannula receiving the wire therethrough, rotation of the handle cannula transferring torque to rotate the wire. The assembly also includes a shaft receiving the handle cannula, rotation of the shaft transferring torque to rotate the handle cannula. The assembly further includes an actuation assembly receiving the shaft, the actuation assembly coupled to a sheath sized to receive the wire and end effector therethrough, the actuation assembly moveable between a proximal configuration in which the sheath is moved proximally to expand the end effector and a distal configuration in which the sheath is moved distally to retract the end effector, the actuation assembly including a rotation mechanism transferring torque to the shaft to rotate the shaft.

Provided is a digestive-tract treatment method including: pulling, inside a digestive tract (A), an end portion of a first wall portion (A1) positioned at a rim of a treatment target site (B), and moving the first wall portion (A1) to a position on a second wall portion (A2) on an opposite side of the treatment target site (B) from the first wall portion (A1); and joining the first wall portion (A1) and the second wall portion (A2) in a state in which the first wall portion (A1) and the second wall portion (A2) are layered.

The disclosure provides various embodiments of catheters having articulable ends that can be used for various procedures. Embodiments of methods are also provided that can be performed with catheters in accordance with the present disclosure.