Patent ID: 7879034
Filing Date: 2011-02-01
Classification: A61B

Abstract:
1. An electrosurgical apparatus comprising: a shaft having a proximal end portion and a distal end portion; an active electrode disposed on a surface of the distal end portion of the shaft; a return electrode disposed within the distal end portion of the shaft; wherein the shaft comprises a conductive cap disposed at a distal end of the shaft and in electrical communication with the return electrode and wherein the cap is spaced sufficiently from the active electrode to minimize generation of an electric arc between the active electrode and the cap; wherein the shaft comprises an insulating member positioned on the distal end portion of the shaft and preventing direct electrical contact between the active and return electrodes; and electrical conductors adapted for applying a radio-frequency voltage difference across the active and return electrodes, wherein the active electrode and return electrode define an interconnecting passageway within the distal end portion of the shaft such that the interconnecting passageway is between the active electrode and the return electrode, the interconnecting passageway allowing for electrical communication therein between the active electrode and the return electrode in the presence of an electrically conductive fluid, and so that upon application of the radio-frequency voltage difference across the active and return electrodes electric fields generated between the active and return electrodes are mostly contained within the shaft.