Patent ID: 6482202
Filing Date: 2002-11-19
Classification: A61B,A61M

Abstract:
An electrosurgical instrument for the treatment of tissue in the presence of an electrically-conductive fluid medium, the instrument comprising an instrument shaft, and an electrode assembly at one end of the shaft, the electrode assembly comprising a tissue treatment electrode and a return electrode which is electrically insulated from the tissue treatment electrode by means of an insulation member, the tissue treatment electrode having an exposed surface for treating tissue, and the return electrode having a fluid contact surface which is spaced proximally from the tissue treatment electrode in such a manner as to define, in use, a conductive fluid path that completes an electrical circuit between the tissue treatment electrode and the return electrode, wherein the electrode assembly is provided with at least one aperture in the region of the tissue treatment electrode through which vapour bubbles and/or particulate material can be aspirated from the region surrounding the tissue treatment electrode, and a plurality of fluid pathways leading to the aperture formed by the tissue treatment electrode.