Patent Publication Number: US-2011060335-A1

Title: Apparatus for Tissue Fusion and Method of Use

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates to an apparatus and method for the fusion of internal tissue and, more particularly, to jaw members including integrally formed stop members. 
     2. Background of Related Art 
     Devices for fusing or sealing internal tissue are known. Many of such devices include a pair of jaw members extending from a distal end of a handle assembly. Typically, one or both of the jaw members include an electrode operably connected to an electrosurgical generator. Tissue received between the jaw members are fused through a combination of pressure exerted on the tissue by the jaw members, the gap distance between the jaw members and the electrosurgical energy provided to the electrodes. 
     In order to effect a proper seal with larger vessels, two predominant mechanical parameters should be accurately controlled—the pressure applied to the vessel and the gap distance between the electrodes—both of which are affected by the thickness of the sealed vessel. With respect to smaller vessels, the pressure applied to the tissue tends to become less relevant whereas the gap distance between the electrically conductive surfaces becomes more significant for effective sealing. 
     To prevent contact of the electrodes and to set a proper gap for sealing, one or more stop members have been placed on either or both of the jaw members and/or the electrodes. These stop members are composed of ceramic or other suitable insulting material. The addition of a stop member on either or both of the jaw members increases the overall size of the device and/or reduces the size of the sealing surface. As more and more procedures are being performed laparoscopicly, arthroscopicly, endoscopically, and otherwise, there exists a need for smaller sealing devices. 
     SUMMARY 
     Accordingly, an end effector for an electrosurgical forceps is provided. The end effector includes a first jaw member having proximal and distal ends, the distal end including a recess defined therein and a second jaw member having proximal and distal ends. The distal end of the second jaw member including a first prong configured for receipt within the recess defined in the first jaw member. Engagement of the first prong of the second jaw member within the recess of the first jaw member creates a gap between the first and second jaw members and is configured to prevent splaying of the first and second jaw members relative to one another. 
     In one embodiment, the gap between the first and second jaw members is about 0.001 inches to about 0.006 inches. The first jaw member may include a first electrode and the second jaw member may include a second electrode, the first electrode positioned proximal to the recess and the second electrode positioned proximal to the first prong. The first and second electrodes may be flush relative to respective first and second tissue contacting surface of respective first and second jaw members. The recess in the first jaw member may be defined by a pair of prongs extending from a distal end thereof. The first prong in the second jaw member may include a pair of shoulder portions configured to engage the pair of prongs formed in the first jaw member. 
     Also provided is a system for the treating of tissue. The system includes an apparatus having first and second jaw members configured to selectively receive tissue therebetween. The first jaw member includes proximal and distal ends, the distal end defining a recess therein. The second jaw member includes proximal and distal ends, the proximal end of the second jaw member pivotably coupled to the proximal end of the first jaw member. The distal end of the second jaw member is in a spaced apart relationship with the first jaw member when in a first position, and the distal end of the second jaw member is received within the recess formed in the first jaw member when in a second position. A gap is formed between the first and second jaw members when in the second position, and a source of electrosurgical energy may be operably connected to at least one of the jaw members to deliver electrosurgical energy to the tissue. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing summary, as well as the following detailed description will be better understood when read in conjunction with the appended figures. For the purpose of illustrating the present disclosure, various embodiments are shown. It is understood, that the present disclosure is not limited to the precise arrangement and instrumentalities shown. 
         FIG. 1  is a side view of a distal end of forceps jaws according to an embodiment of the present disclosure, in a first or closed position; 
         FIG. 2  is an end view of the forceps jaws of  FIG. 1 ; 
         FIG. 3A  is a partial, top view of the bottom jaw member of  FIGS. 1 and 2 ; 
         FIG. 3B  is a partial, top view of the top jaw member of  FIGS. 1 and 2 ; 
         FIG. 4  is a partial, cross-sectional, side view of the jaw members of  FIGS. 1-3 , shown in a first or closed position, operably connected to an endoscopic device including a source of electrosurgical energy; 
         FIG. 5  is a partial, cross-sectional, side view of the jaw members of  FIG. 4 , shown in a second or open position; 
         FIG. 6  is a partial, side view of jaw members according to an alternate embodiment of the present disclosure, shown in a first or closed position; 
         FIG. 7  is a cross-sectional side view of the jaw members of  FIG. 6 ; 
         FIG. 8  is a top view of the bottom jaw member of the jaw members of  FIGS. 6 and 7 ; 
         FIG. 9  is a partial, cross-sectional, side view of the jaw members of  FIGS. 1-3 , shown in a first or closed position, operably connected to an alternate embodiment of an endoscopic device; and 
         FIG. 10  is a partial, cross-sectional, side view of the jaw members of  FIG. 9 , shown in a second or open position. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     For the purpose of illustrating the present disclosure, various embodiments are shown. It is understood, however, that the present disclosure is not limited to the precise arrangement and instrumentalities shown. As shown in the drawings and described throughout the following description, as is traditional when referring to relative positioning on an object, the term “proximal” refers to the end of the apparatus that is closer to the user and the term “distal” refers to the end of the apparatus that is further from the user. 
     Referring to  FIGS. 1-5 , an illustrative embodiment of the presently disclosed jaw members are shown and generally designated as end effector assembly  100 . End effector assembly  100  includes a first jaw member  110  and a second jaw member  120 . In one embodiment, first and second jaw members  110 ,  120  are pivotably connected to one another by a pivot pin  116  ( FIG. 4 ). Alternatively, first and second jaw members  110 ,  120  may be integrally formed ( FIG. 9 ) or otherwise connected. Jaw members  110 ,  120  are configured to retain, seal, cauterize, and/or sever tissue grasped therebetween. 
     End effector assembly  100  may be incorporated into a hand-held instrument for use in open surgical procedures or may instead be configured, as shown, for incorporation into endoscopic or laparoscopic instruments for use in closed surgical procedures. First and second jaw members  110 ,  120  may be composed of plastics, polymers, or other insulative material, and combinations thereof. In one embodiment, first and second jaw members  110 ,  120  may be electrically conductive or have an electrically conductive seal surface. End effector assembly  100  is configured for bipolar operation, as will be discussed below; however, it is envisioned that the aspects of the present disclosure may be modified for monopolar operation. 
     First and second jaw members  110 ,  120  form substantially similar semi-arcuate bases having respective proximal ends  112   a ,  122   a , distal ends  112   b ,  122   b  and body portions  112   c ,  122   c  extending therebetween. First and second jaw members  110 ,  120  may be of the same or differing widths, and of the same or differing lengths. 
     Still referring to  FIGS. 1-3 , in one embodiment, each of first and second jaw members  110 ,  120  includes an electrode  115 ,  125 , respectively, mounted on body portions  112   c ,  122   c , respectively. Electrodes  115 ,  125  may be recessed within first and second jaw members  110 ,  120  such that a top surface thereof is flush with a tissue facing surface  113 ,  123  of first and second jaw members  110 ,  120 , respectively. Alternatively, and as shown, electrodes  115 ,  125  may be placed on tissue facing surface  113   a ,  123   a  of first and second jaw members  110 ,  120 , respectively. Electrodes  115 ,  125  may have a flat, curved or textured tissue contacting surface  119 ,  129 . Electrodes  115 ,  125  are configured for operable connection to a source of electrosurgical energy  40  ( FIG. 4 ). In one embodiment, leads  41 ,  42  operably connect respective electrodes  115 ,  125  to generator  40 . 
     Distal ends  112   b ,  122   b  of first and second jaw members  110 ,  120 , respectively, are configured to prevent electrodes  115 ,  125 , mounted thereon from contacting one another during tissue sealing. With reference to  FIG. 3A , first jaw member  110  includes a pair of prongs  118  forming a curved distal end  112   b . Prongs  118  define a curved recess  119  therebetween. Second jaw member  120  includes a prong  128  forming a curved distal end  122   b . Prong  128  defines a shoulder portions  129  formed on distal end  122   b  of second jaw member  120 . First and second jaw members  110 ,  120  are configured such that when distal ends  112   b ,  122   b  thereof are approximated towards one another, prong  128  of second jaw member  120  is received within or interlocked with curved recess  119  formed between prongs  118  of first jaw member  110 . Prongs  118  of first jaw member  110  are configured to engage shoulder portions  129  of second jaw member  120 . In this manner, prongs  118 ,  128  are configured to maintain body portions  112   c ,  122   e  of first and second jaw members  110 ,  120  in a spaced apart relationship. Thus, a gap  130  is formed between first and second jaw members  110 ,  120 , thereby preventing contact of electrodes  115 ,  125 . Prongs  118  and recess  119  and/or prong  128  and shoulder portions  129  may be configured to provide gap  130  of any size. In this manner, end effector assembly  100  may be configured to seal tissue of various thicknesses. In one embodiment, the gap between first and second jaw members  110 ,  120  and/or first and second electrodes  115 ,  125  is from about 0.001 inches to about 0.006 inches. As discussed above, with respect to smaller vessels, the gap distance between the electrodes becomes more significant for effective sealing than the pressure applied to the tissue. 
     The engagement of prong  128  within recess  119  and the engagement of prongs  118  with shoulders portions  129  cause an interlocking of first and second jaw members  110 ,  120 . This interlocking of distal ends  112   b ,  122   b  of first and second jaw members  110 ,  120 , respectively, maintains first and second jaw members  110 ,  120  in alignment, thereby preventing splaying of jaw members  110 ,  120  as tissue is captured therebetween. 
     Proximal ends  112   a ,  122   a  of first and second members  110 ,  120 , respectively, may be configured for incorporation into a conventional hand-held forceps or for operable engagement with the distal end of an endoscopic or laparoscopic device. With particular reference to  FIGS. 4 and 5 , proximal ends  112   a ,  122   a  of first and second jaw members  110 ,  120 , respectively define openings  114 ,  124 , respectively, therein, configured for operable engagement with respective actuation cables  45 ,  46  extending from a distal end  52   b  of an endoscopic device  50 . First and second actuation cables  45 ,  46  are configured to move first and second jaw members  110 ,  120 . First and second actuation cables  45 ,  46  may operate in unison or independently of each other to pivot first and/or second jaw members  110 ,  120  relative to one another. Actuation cables  45 ,  46  may also be configured to supply electrosurgical energy to first and/or second jaw members  110 ,  120 , respectively, and/or alternatively, to electrodes  115 ,  125  mounted thereon from a source of electrosurgical energy  40 . 
     Referring to  FIG. 5 , end effector assembly  100  is shown in a second or open position. In the open position, distal ends  112   b ,  122   b  of first and second jaw members  110 ,  120  are pivoted away from one another to form an opening  135  between first and second jaw members  110 ,  120 . Opening  135  is configured for facilitating the placement of end effector assembly  100  about a portion of tissue, such as, for example the stem of a polyp or a vessel. Depending on the configuration of the actuation mechanism, and whether for open or closed procedures, first jaw member  110  may be held stationary relative to the actuation assembly (not shown) while second jaw member  120  is pivoted about pivot pin  116  relative to first jaw member  110 . In an alternate embodiment, both first and second jaw members may be pivoted relative to each other, while in yet another embodiment, second jaw member  120  may be held stationary relative to the actuation assembly while first jaw member  110  is pivoted about pivot pin  116  relative to second jaw member  120 . First and second jaw member  110 ,  120  may be articulated up to and beyond ninety degrees (90°) relative to one another. The range of articulation of second jaw member  120  relative to first jaw member  110  is limited only by the range of motion of the actuation assembly connected thereto. 
     Turning now to  FIGS. 1 and 4 , end effector assembly  100  is shown in a first or closed position. In the closed position, gap  130  formed between first and second jaw members  110 ,  120  is configured for operably retaining the stem of a polyp or other tissue. Whether end effector assembly  100  is of a monopolar or a bipolar design, electrosurgical energy is applied to either first and/or second electrodes  115 ,  125 , at any time during the tissue sealing procedure. For tissue having a greater thickness, it may be necessary to activate the tissue sealing mechanism prior to the complete closure of first and second jaw members  110 ,  120 . As discussed above, the receipt of first prong  128  of second jaw member  120  within recess  119  of first jaw member  110  also prevents the splaying of first and second jaw members  110 ,  120  as tissue is received and sealed therebetween. 
     Referring now to  FIGS. 6-8 , an end effector assembly in accordance with an alternate embodiment of the present disclosure is shown generally as end effector assembly  200 . End effector assembly  200  are substantially similar to end effector assembly  100  and will only be described with respect to the difference in construction and operation therebetween. End effector assembly  200  includes first and second jaw members  210 ,  220 . First jaw member  210  forms a level, planar, or linear base including proximal and distal ends  212   a ,  212   b , and a body portion  212   c  therebetween. Second jaw member  220  includes proximal and distal ends  222   a ,  222   b  and a body portion  222   c  therebetween. As shown, first and second jaw members  210 ,  220  are integrally connected at proximal ends  212   a ,  222   a , respectively, thereof. In an alternate embodiment, first and second jaw members  210 ,  220  may be pivotally connected to one another using mechanical fasteners or other suitable affixation methods. Each of first and second jaw members  210 ,  220  includes an electrode  215 ,  225 , respectively. In the illustrated embodiment, electrodes  215 ,  225  are recessed within first and second jaw members  210 ,  220  such that tissue contacting surfaces  213 ,  223  of electrodes  215 ,  225 , respectively, are flush with respective tissue contacting surfaces  213 ,  223  of respective first and second jaw members  210 ,  220 . 
     With continued reference to  FIGS. 6-8 , a shelf or recess  219  is formed in distal end  212   b  of first jaw member  210 . A tip  228  is formed in distal end  222   b  of second jaw member  220  and is configured to be received within recess  219  of first jaw member  210  when jaws  200  are in a closed position. The receipt of tip  228  within recess  219  prevents splaying of first and second jaw members  210 ,  220 . The receipt of tip  228  within recess  219  also maintains a gap  230  between first and second jaw members  210 ,  220  and prevents deflection of second jaw member  220 . The width of gap  230  may vary depending on the configuration, i.e. arc, length, tip  228  of second jaw member  220  and/or the depth of recess  219  of first jaw member  210 . 
     With reference now to  FIGS. 9 and 10 , an alternate embodiment of an actuation mechanism for controlling end effector assembly  300  is shown generally as endoscopic device  350 . End effector assembly  300  is substantially similar to end effector assembly  100  described hereinabove. End effector assembly  300  extends from tubular body  352  of endoscopic device  350 , in the direction of arrows “A”, causing first and second jaw members  310 ,  320  to approximate away from each other, in the direction of arrows “B”. Alternatively, tubular body  352  may be retracted relative to end effector assembly  300  to permit the opening of end effector assembly  300 . End effector assembly  300  is next positioned about a portion of tissue (not shown) to be sealed. Retraction of a handle  355  of endoscopic instrument  350 , in the direction of arrows “C”, causes end effector assembly  300  to engage a distal end  352   b  of tubular body  352 . Continued retraction of handle  355  causes distal ends  312   b ,  322   b  of first and second jaw members  310 ,  320 , respectively, to approximate towards each other, in the direction of arrows “D”, until distal end  322   h  of second jaw member  320  engages distal end  312   b  of first jaw member  310 . 
     Thus, it should be understood that various changes in form, detail and operation of the tissue removal jaws of the present disclosure may be made without departing from the spirit and scope of the present disclosure.