Abstract: An electrosurgical instrument with a movable fluid delivery sheath assembly for variable fluid supply during surgical procedures is disclosed. The instrument comprises at least one active electrode and at least one return electrode, positioned on the instrument distal end. The sheath assembly has an outer sheath that is external to the instrument shaft, to provide a lumen. The sheath assembly lumen is axially movable between first and second positions relative to a fluid delivery element, for varying target site treatment and fluid delivery. In the first position the shaft distal end is axially distal to a leading edge of the sheath assembly. In the second position the sheath assembly distal leading edge is positioned axially adjacent or distal to the end of the shaft. The fluid delivery element comprises an inner lumen extending through at least a portion of the shaft, and at least one port extending radially through the shaft. The port is in communication with the inner lumen.

Abstract: An electrosurgical instrument having active and return electrodes with a movable suction sheath for variable fluid and debris removal during surgical procedures is disclosed. The suction apparatus has an outer sheath that is external to a shaft to provide a lumen. The sheath assembly is axially movable relative to the fluid aspiration element between first and second positions for treating the target site and fluid and debris removal, respectively. The first position positions the distal end of the shaft axially distal to a leading edge of the sheath assembly. The second position positions the distal leading edge of the sheath assembly axially adjacent to the end of the shaft. The fluid aspiration element comprises an inner lumen extending through the shaft, and at least one port extending radially through the shaft. The port is in communication with the inner lumen. A vacuum provides suction through the port and inner lumen.

Abstract: An electrosurgical instrument with a movable fluid delivery sheath assembly for variable fluid supply during surgical procedures is disclosed. The instrument comprises at least one active electrode and at least one return electrode, positioned on the instrument distal end. The sheath assembly has an outer sheath that is external to the instrument shaft, to provide a lumen. The sheath assembly lumen is axially movable between first and second positions relative to a fluid delivery element, for varying target site treatment and fluid delivery. In the first position the shaft distal end is axially distal to a leading edge of the sheath assembly. In the second position the sheath assembly distal leading edge is positioned axially adjacent or distal to the end of the shaft. The fluid delivery element comprises an inner lumen extending through at least a portion of the shaft, and at least one port extending radially through the shaft. The port is in communication with the inner lumen.

Abstract: An electrosurgical instrument having active and return electrodes with a movable suction sheath for variable fluid and debris removal during surgical procedures is disclosed. The suction apparatus has an outer sheath that is external to a shaft to provide a lumen. The sheath assembly is axially movable relative to the fluid aspiration element between first and second positions for treating the target site and fluid and debris removal, respectively. The first position positions the distal end of the shaft axially distal to a leading edge of the sheath assembly. The second position positions the distal leading edge of the sheath assembly axially adjacent to the end of the shaft. The fluid aspiration element comprises an inner lumen extending through the shaft, and at least one port extending radially through the shaft. The port is in communication with the inner lumen. A vacuum provides suction through the port and inner lumen.

Abstract: Systems and methods are provided for applying a high frequency voltage in the presence of an electrically conductive fluid. High frequency voltage is then applied between the active electrode(s) and one or more return electrode(s) to volumetrically remove or ablate at least a portion of the target tissue. In one embodiment a tissue treatment surface includes spacers or a chamber for containing the electrodes.

Abstract: Systems and methods are provided for applying a high frequency voltage in the presence of an electrically conductive fluid to create a relatively low-temperature plasma for ablation of tissue adjacent to, or in contact with, the plasma. In one embodiment, an electrosurgical probe or catheter is positioned adjacent the target site so that one or more active electrode(s) are brought into contact with, or close proximity to, a target tissue in the presence of electrically conductive fluid. High frequency voltage is then applied between the active electrode(s) and one or more return electrode(s) to non-thermally generate a plasma adjacent to the active electrode(s), and to volumetrically remove or ablate at least a portion of the target tissue. The high frequency voltage generates electric fields around the active electrode(s) with sufficient energy to ionize the conductive fluid adjacent to the active electrode(s).