Flexible instruments and associated systems and methods are disclosed herein. In some embodiments, a flexible instrument comprises an elongate device having an inner conductor, an outer conductor surrounding the inner conductor, and a dielectric layer insulating the inner conductor from the outer conductor. The flexible instrument further includes a recess formed in the outer conductor. An insert is positioned within the recess and about the inner conductor.

Electrical instrument for applying radiofrequency and/or microwave frequency energy to tissue, comprising: a distal part comprising an instrument tip for applying radiofrequency and/or microwave frequency energy to tissue, the instrument tip comprising first and second conductive elements; a coaxial feed cable comprising an inner conductor, a tubular outer conductor coaxial with the inner conductor, and dielectric material separating the inner and outer conductors, the coaxial feed cable being for conveying radiofrequency and/or microwave frequency energy to the distal part; wherein: the inner conductor is electrically connected to the first conductive element and the outer conductor is electrically connected to the second conductive element through a rotatable connection between the distal part and the coaxial feed cable that allows rotation of the distal part relative to the coaxial feed cable; and the instrument comprises an actuator for rotating the distal part in a first rotational direction relative to the feed cable.

An electrosurgical device (10) operable to deliver microwave energy to cause targeted tissue ablation is provided. The electrosurgical device (10) comprises an antenna (26), a reflector (30), and a dielectric material (34) disposed therebetween. The selection of the dielectric material (30) and the relative positioning of the antenna (26) and the reflector (30) provide impedance matching between the antenna (26) and a transmission line (12) so as to minimize heating along the length of the device (10) during use.

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.

Described herein are devices, systems, and methods for wireless power transfer utilizing a midfield source and implant. In one variation, a midfield source may be realized by a patterned metal plate composed of one of more subwavelength structures. These midfield sources may manipulate evanescent fields outside a material (e.g., tissue) to excite and control propagating fields inside the material (e.g., tissue) and thereby generate spatially confined and adaptive energy transport in the material (e.g., tissue). The energy may be received by an implanted device, which may be configured for one or more functions such as stimulation, sensing, or drug delivery.

A microwave ablation antenna assembly (20) incorporates an improved choke assembly (40) which provides the antenna assembly (20) with both a largely spherical ablation pattern and an improved impedance matching characteristic.

Embodiments of the invention provide an energy conveying structure for delivering RF and/or microwave energy to an electrosurgical instrument, where the energy conveying structure is incorporated into an insertion tube of a surgical scoping device (e.g. endoscope, laparoscope or the like). The insertion tube is a flexible conduit that is introduced into a patient's body during an invasive procedure, and can include an instrument channel and an optical channel. The energy conveying structure may be a layered coaxial structure that formed a liner that fits within the scoping device, e.g. within an instrument channel. Alternatively, the energy conveying structure may be a coaxial structure integrally formed as part of the flexible conduit.

An electrosurgical system includes an electrosurgical power generating source, an energy applicator operably associated with the electrosurgical power generating source, a processor unit, and a data acquisition module configured to receive a reflected signal. The processor unit is disposed in operative communication with the data acquisition module and adapted to determine a tissue desiccation rate around at least a portion of the energy applicator based on one or more signals received from the data acquisition module.

A microwave ablation system includes an antenna assembly configured to deliver microwave energy from a power source to tissue. One or more electrodes are disposed on the antenna assembly and are configured to be positioned relative to tissue upon insertion of the antenna assembly into tissue. The one or more electrodes are configured to generate a feedback signal in response to an electrical signal supplied thereto from the power source. The feedback signal corresponds to the proximity of tissue relative to the at least one electrode and is configured to be compared to a predetermined parameter to determine a depth of the insertion of the antenna assembly into tissue. The power source is configured to control the delivery of microwave energy to the antenna assembly based on the comparison.

An electrosurgical device (10) operable to deliver microwave energy to cause targeted tissue ablation is provided. The electrosurgical device (10) comprises an antenna (26), a reflector (30), and a dielectric material (34) disposed therebetween. The selection of the dielectric material (30) and the relative positioning of the antenna (26) and the reflector (30) provide impedance matching between the antenna (26) and a transmission line (12) so as to minimize heating along the length of the device (10) during use.