Patent ID: 8167878

Claim:
An electrosurgical probe for cutting or coagulating tissue, the electrosurgical probe comprising: a sheath; first and second conductors disposed in the sheath and carrying a radio frequency current to and from a distal end of the sheath; a first electrode protruding or adapted to extend from the distal end of the sheath so as to define a distance between the first electrode and the distal end of the sheath, the first electrode being electrically insulated from the sheath, electrically connected to the first conductor to define an active pole of a radio frequency circuit, and configured to perform cutting or coagulation of tissue when the radio frequency current flows to the first electrode; a second electrode protruding or adapted to extend from the distal end of from the sheath, the second electrode being attached to a distal end of the second conductor and disposed entirely between the first conductor and the first electrode to define a gap with the first electrode that is less than the distance between the first electrode and the distal end of the sheath, the second electrode being electrically insulated from the sheath, and configured to define a focused ground point in close proximity to the active pole defined by the first electrode so as to complete the radio frequency circuit with the first electrode when a conductive fluid surrounds the first and second electrodes and the radio frequency current flows to the first electrode; and means for passing the radio frequency current through the first conductor, from the first electrode and through the gap to the second electrode, and through the second conductor without conducting the radio frequency current through the sheath.