Fine dissection electrosurgical device

A system comprising:

• an electrosurgical controller, the electrosurgical controller configured to produce radio frequency (RF) energy at an active terminal with respect to a return terminal;
• an electrosurgical wand coupled to the electrosurgical controller, the electrosurgical wand comprising:
• an elongate shaft that defines a handle end and a distal end;
• an insulative sheath characterized by a plurality of discharge apertures on the distal end of the elongate shaft, the plurality of discharge apertures fluidly coupled to a first fluid conduit, and the first fluid conduit within the elongate shaft;
• a first active electrode of conductive material disposed on the distal end of the elongate shaft;
• wherein the first active electrode has an edge feature, and the first active electrode electrically coupled to the first electrical pin;
• a first return electrode of conductive material, the first return electrode comprising an extended feature disposed a substantially constant distance from a distal apex of the first active electrode, and the first return electrode electrically coupled to the second electrical pin;
• and
• an aspiration aperture on the distal end of the elongate shaft;
• the aspiration aperture having an aperture width and fluidly coupled to a spacer fluid conduit, the conduit transitioning in width from the aperture width to a fluid conduit opening width not less than half an internal diameter of the shaft.

A method comprising:

• flowing a conductive fluid within a fluid conduit disposed within a electrosurgical wand, wherein the conductive fluid discharges through a plurality of discharge apertures flows past a return electrode disposed distally from the fluid conduit over an active electrode, and is then aspirated though an aspiration aperture that is offset from a plane that bisects the thickness of the active electrode;
• applying electrical energy between the active electrode and the return electrode;
• forming, responsive to the energy, a localized plasma proximate to an edge feature disposed on the active electrode;
• ablating, by the localized plasma, a portion of a target tissue proximate to the edge feature;
• and
• heating, responsive to the energy, the target tissue proximate to a smooth feature disposed on the active electrode at locations spaced away from the edge feature to thereby provide concomitant hemostasis.

An electrosurgical wand comprising:

• an elongate shaft that defines a handle end and a distal end;
• a connector comprising first and second electrical pins;
• a first active electrode of conductive material disposed on the distal end of the elongate shaft, the first active electrode is electrically coupled to the first electrical pin;
• wherein the first active electrode has an edge feature at a first discrete location, and a smooth feature at a second discrete location;
• and
• a first return electrode of conductive material, the first return electrode electrically coupled to the second electrical pin;
• and
• an aspiration aperture on the distal end of the elongate shaft, defining an aspiration aperture width and wherein the aspiration aperture is fluidly connected with a spacer fluid conduit, the conduit transitioning in width from the aperture width to a fluid conduit opening width that is not less than half an internal diameter of the shaft.

An electrosurgical wand comprising:

• an elongate shaft that defines a handle end and a distal end;
• a connector comprising first and second electrical pins;
• an insulative sheath characterized by a plurality of discharge apertures on the distal end of the elongate shaft, the plurality of discharge apertures fluidly coupled to a first fluid conduit, and the first fluid conduit within the elongate shaft;
• a first active electrode of conductive material disposed on the distal end of the elongate shaft, the first active electrode electrically coupled to the first electrical pin, and having an edge feature;
• a non-conductive spacer disposed adjacent the first active electrode, the spacer comprising a step feature operable to limit the tissue penetration depth of the first active electrode;
• a first return electrode of conductive material, the first return electrode comprising an extended feature disposed a substantially constant distance from a distal apex of the first active electrode, and the first return electrode electrically coupled to the second electrical pin;
• and
• an aspiration aperture on the distal end of the elongate shaft fluidly coupled to a second fluid conduit, the second fluid conduit within the elongate shaft.

An electrosurgical wand comprising:

• an elongate shaft that defines a handle end and a distal end;
• a connector comprising a first and second electrical pins;
• an insulative sheath characterized by a plurality of discharge apertures on the distal end of the elongate shaft, the plurality of discharge apertures fluidly coupled to a first fluid conduit, and the first fluid conduit within the elongate shaft;
• a first active electrode of conductive material disposed on the distal end of the elongate shaft, the first active electrode electrically coupled to the first electrical pin and including an edge feature;
• a first return electrode of conductive material, the first return electrode comprising an extended feature disposed a substantially constant distance from a distal apex of the first active electrode, and the first return electrode electrically coupled to the second electrical pin;
• and
• an aspiration aperture on the distal end of the elongate shaft fluidly coupled to a second fluid conduit, the second fluid conduit within the elongate shaft;
• and wherein the aspiration aperture defines an aperture width, and wherein a spacer fluid conduit transitions in width from the aperture width to a fluid conduit opening width not less than half an internal diameter of the shaft.

A system comprising:

• an electrosurgical controller, the electrosurgical controller configured to produce radio frequency (RF) energy at an active terminal with respect to a return terminal;
• an electrosurgical wand coupled to the electrosurgical controller, the electrosurgical wand comprising:
• an elongate shaft that defines a handle end and a distal end;
• an insulative sheath characterized by a plurality of discharge apertures on the distal end of the elongate shaft, the plurality of discharge apertures fluidly coupled to a first fluid conduit, and the first fluid conduit within the elongate shaft;
• a first active electrode of conductive material disposed on the distal end of the elongate shaft, the first active electrode electrically coupled to the first electrical pin and including an edge feature;
• a first return electrode of conductive material, the first return electrode comprising an extended feature disposed a substantially constant distance from a distal apex of the first active electrode, and the first return electrode electrically coupled to the second electrical pin;
• and
• an aspiration aperture on the distal end of the elongate shaft fluidly coupled to a second fluid conduit, the second fluid conduit within the elongate shaft and wherein the aspiration aperture is offset from a plane that bisects the thickness of the distal end of the elongate shaft.