| 摘要 |
An electrosurgical snare 100 is arranged to radiate microwave frequency energy (e.g. >1 GHz) from an elongate conductive antenna 122 within an area encircled by a retractable loop 118. The antenna is coupled to the inner conductor 104 of a coaxial cable 106 which delivers microwave energy from a generator to the probe tip, where the cable is capped by an insulating snare base 112 having a feed channel to guide passage of the retractable loop. The antenna and retractable loop may be independently slidable relative to the snare base to aid deployment. The antenna may be a straight extension of the inner coax conductor (in which case the retractable loop is of electrically conductive material), or it may be a flexible C-shaped element (132, figure 2A) or it may be a conductive coating (142, figure 3A) on the retractable loop. The probe may be sized for insertion down the instrument channel of an endoscope. |
