Apparatus for retrieving a tissue volume with improved positioning precursor assembly

Abstract

Apparatus for retrieving a tissue volume of a variety utilizing an electrosurgically excited cable implemented capture component which performs in combination with an improved precursor assembly. Where that assembly is electrosurgically excited, then it is located and dimensioned to avoid arc-over with the capture component cables. A precursor assembly also is implemented with electrically insulative ceramic blade and trocar configurations.

1 - 7 . (canceled) 
   
   
       8 . Apparatus for retrieving a tissue volume, comprising:
 a delivery assembly with a delivery member having a member exterior surface surmounting an interior channel assembly extending from a proximal portion along an axis to a forward region having a distal end, said delivery member exhibiting a member widthwise extent;   a capture component positioned at said delivery member forward region, having a forward portion extending to a forwardly disposed tip region with a pursing cable assembly energizable to define an electrosurgical cutting leading portion, said cable assembly including tensionable cables extending from said forward portion at a deployment location, thence along said interior channel assembly to a cable terminator, said forward portion being drivably extendable from an initial position, wherein portions of said cables extend about said member exterior surface at said deployment location, outwardly from said exterior surface and forwardly at a tip region angle of attack, while creating an electrosurgical arc, toward an intermediate position while drawing said cables along a laterally outwardly expanding locus of travel, said electrosurgical cutting leading portion defining a cutting profile of maximum effective diametric extent in correspondence with said intermediate position, and subsequently being drivably extendable while being drawn in contraction toward said axis at tip region inwardly directed pursing angles of attack by pursing stress at said cable assembly to a capture position;   a precursor assembly supported at said delivery member distal end, having one or more cutting edges of surgical sharpness extending in correspondence with said member widthwise extent and being electrically insulative to an extent effective to avoid arc-over with said capture component pursing cable assembly; and   a control assembly having a drive portion in driving engagement with said capture component and actuatable to drive said capture component forward portion from said initial position while effecting the electrosurgical energization of said pursing cable assembly.   
   
   
       9 . The apparatus of  claim 8  in which said precursor assembly comprises:
 a first electrically insulative ceramic blade having oppositely disposed first surfaces with a generally triangular periphery aligned with said axis, with a base fixed adjacent said delivery member distal end and co-extensive with said member widthwise extent, said periphery having surgically sharp edges extending from said base to a first apex aligned with said axis.   
   
   
       10 . The apparatus of  claim 8  in which said first ceramic blade is formed of a zirconia material. 
   
   
       11 . The apparatus of  claim 9  in which said precursor assembly further comprises:
 an electrically insulative tissue spreader in adjacency with each said first surface, generally symmetrically aligned with said axis, and extending in a tapering configuration from adjacency with said base to adjacency with said surface at an axially aligned location below said first apex.   
   
   
       12 . The apparatus of  claim 9  in which said precursor assembly comprises:
 a second electrically insulative ceramic blade having oppositely disposed second surfaces aligned with said axis, and generally normally to a said first surface, having a generally right triangular periphery with a base fixed adjacent said delivery member distal end and having a hypotenuse related surgically sharp edge extending to a second apex in adjacency with a said first surface.   
   
   
       13 . The apparatus of  claim 12  in which:
 said second apex is inwardly disposed from said first apex.   
   
   
       14 . The apparatus of  claim 12  in which said second ceramic blade is formed of a zirconia material. 
   
   
       15 . The apparatus of  claim 12  in which said precursor assembly further comprises:
 a third electrically insulative ceramic blade having oppositely disposed third surfaces aligned with said axis, disposed oppositely from said second ceramic blade and generally normally to a said first surface, having a generally right triangular periphery with a base fixed adjacent said delivery member distal end and a hypotenuse related surgically sharp edge extending to a third apex in adjacency with a said first surface.   
   
   
       16 . The apparatus of  claim 15  in which:
 said third apex is inwardly disposed from said first apex and aligned with said second apex.   
   
   
       17 . The apparatus of  claim 15  in which said third ceramic blade is formed of a zirconia material. 
   
   
       18 . The apparatus of  claim 8  in which said precursor assembly comprises:
 a unitary solid electrically insulative cutting member formed of a ceramic material having a base supported at said delivery member distal end and extending symmetrically disposed about said axis to a single point apex from which two or more surgically sharp edges symmetrically disposed about said axis extend inwardly.   
   
   
       19 . The apparatus of  claim 18  in which:
 said ceramic material is zirconia.   
   
   
       20 . The apparatus of  claim 8  in which:
 said precursor assembly comprises:   an electrically conductive electrosurgically excitable blade assembly having a base supported at said delivery member distal end, having one or more cutting edges of surgical sharpness extending from said base, said blade assembly being coated with an electrically insulative material with the exception of a portion of one or more said cutting edges spaced axially forwardly from said capture component cables at said initial position a distance, x, effective to avoid arc-over when said blade assembly is electrosurgically excited; and   said control assembly is actuateable to electrosurgically excite said blade assembly when said cables are de-energized.   
   
   
       21 . Apparatus for retrieving a tissue volume, comprising:
 a delivery assembly with a delivery member having a member exterior surface surmounting an interior channel assembly extending from a proximal portion along an axis to a forward region having a distal end, said delivery member exhibiting a member profile with a member effective diameter and radius extending to said profile from said axis at said distal end;   a capture component positioned at said delivery member forward region, having a forward portion extending to a forwardly disposed tip region with a pursing cable assembly energizable to define an electrosurgical cutting leading portion, said cable assembly including tensionable cables extending from said forward portion at a deployment location, thence along said interior channel assembly to a cable terminator, said forward portion being drivably extendable from an initial position, wherein positions portions of said cables extend about said member exterior surface at said deployment location, outwardly from said exterior surface and forwardly at a tip region angle of attack, while creating an electrosurgical arc, toward an intermediate position while drawing said cables along a laterally outwardly expanding locus of travel, said electrosurgical cutting leading portion defining a cutting profile of maximum effective diametric extent in correspondence with said intermediate position, and subsequently being drivably extendable while being drawn in contraction toward said axis at tip region inwardly directed pursing angles of attack by pursing stress at said cable assembly to a capture position;   a precursor assembly formed with electrically insulative material, having a base with a profile substantially coextensive with said member profile and extending therefrom with one or more cutting edges of surgical sharpness to an apex generally coincident with said axis; and   a control assembly having a drive portion in driving engagement with said capture component and actuatable to drive said capture component forward portion from said initial position while effecting the electrosurgical energization of said pursing cable assembly.   
   
   
       22 . The apparatus of  claim 21  in which:
 said precursor cutting edges are formed of a ceramic material.   
   
   
       23 . The apparatus of  claim 22  in which said ceramic material is a zirconia material. 
   
   
       24 . The apparatus of  claim 21  in which said precursor assembly further comprises:
 a first electrically insulative ceramic blade having oppositely disposed first surfaces aligned with said axis, having a generally right triangular periphery with a first base fixed adjacent said delivery member distal end and having a hypotenuse related first cutting edge extending to said apex.   
   
   
       25 . The apparatus of  claim 24  in which said precursor assembly further comprises:
 one or more electrically insulative tissue spreaders extending from adjacency with at least a portion of said member profile in tapering adjacency with said first surfaces to a location inwardly spaced from said apex.   
   
   
       26 . The apparatus of  claim 24  in which:
 said first base of said first ceramic blade corresponds with said member radius and said first cutting edge extends from said member profile to said apex; and   said precursor assembly further comprises:   a second electrically insulative ceramic blade having oppositely disposed second surfaces aligned with said axis, having a generally right triangular periphery with a second base fixed adjacent said delivery member distal end and having a hypotenuse related second cutting edge extending from said member profile to said apex.   
   
   
       27 . The apparatus of  claim 26  in which said precursor assembly further comprises:
 one or more electrically insulative tissue spreaders extending from at least a portion of said member profile in tapering fashion in adjacency with said first and second surfaces to a location symmetrically disposed about said axis and inwardly spaced from said apex.   
   
   
       28 . The apparatus of  claim 26  in which said precursor assembly further comprises:
 a third electrically insulative ceramic blade having oppositely disposed third surfaces aligned with said axis, having a generally right triangular periphery with a third base fixed adjacent said delivery member distal end and having a hypotenuse related third cutting edge extending from said member profile to said apex; and   said first, second and third ceramic blades being symmetrically disposed about said axis.   
   
   
       29 . The apparatus of  claim 28  in which said precursor assembly further comprises:
 one or more electrically insulative tissue spreaders extending from adjacency with at least a portion of said member profile in tapering adjacency with said first, second and third surfaces to a location symmetrically disposed about said axis and inwardly spaced from said apex.   
   
   
       30 . The apparatus of  claim 28  in which said precursor assembly further comprises:
 a fourth electrically insulative ceramic blade having oppositely disposed fourth surfaces aligned with said axis, having a generally right triangular periphery with a fourth base fixed adjacent said delivery member distal end and having a hypotenuse related fourth cutting edge extending from said member profile to said apex.   
   
   
       31 . The apparatus of  claim 30  in which said precursor assembly further comprises:
 one or more electrically insulative tissue spreaders extending from adjacency with at least a portion of said member provide in tapering adjacency with said first, second, third and fourth surface to a location symmetrically disposed about said axis and inwardly spaced from said apex.   
   
   
       32 . The apparatus of  claim 27  in which said third ceramic blade is formed of a zirconia material.