An electrosurgical instrument, which is used to treat tissue in the presence of an electrically-conductive fluid, comprises an instrument shaft and an electrode assembly at one end of the shaft. The electrode assembly comprises a tissue treatment electrode (11) and a return electrode (12) which is electrically...http://www.google.com/patents/US6174308?utm_source=gb-gplus-sharePatent US6174308 - Electrosurgical instrument
