Abstract:
An end effector assembly for an electrosurgical instrument is provided. The end effector assembly has a pair of first and second jaw members including respective seal having a width. Each of the seal plates adapted to connect to an energy source. The first and second jaw members are operable in a first mode of operation for treating tissue and a second mode of operation for separating tissue. The width of the seal plate of the first jaw member is smaller than the width of the seal plate of the second jaw member. In the second mode of operation the seal plate of the first jaw member is independently activatable from the seal plate of the second jaw member to facilitate the separation of tissue when the first and second jaw members are in one of the open and clamping positions.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to an electrosurgical instrument and, more particularly, to an electrosurgical instrument configured to dissect, seal or otherwise treat tissue. 
         [0003]    2. Background of Related Art 
         [0004]    Electrosurgical instruments, e.g., electrosurgical forceps (open type or closed type, i.e., suitable for a laparoscopic procedure), are well known in the medical arts and typically include an end effector assembly including jaw members configured to manipulate tissue (e.g., grasp and seal tissue). Typically, the electrosurgical forceps utilizes both mechanical clamping action and electrical energy to effect hemostasis by heating the tissue and blood vessels to coagulate, cauterize, seal, desiccate, and/or fulgurate tissue. 
         [0005]    In certain instances, it may prove advantageous to cut or dissect tissue that has been electrosurgically treated, e.g., sealed. In such instances, a cutting element, e.g., a knife blade, may be configured to translate through a knife channel that is disposed on one or both of the jaw members. As can be appreciated, incorporating the knife blade into the electrosurgical instrument may increase manufacturing costs of the electrosurgical instrument. In addition, manufacturing tolerances typically associated with the placement of the knife channel on one or both of the jaw members need to be kept at a minimum. That is, the knife blade needs to be substantially aligned with the knife channel during the manufacture of the end effector and/or jaw members. As can be appreciated, if the knife blade and knife channel are not substantially aligned with each other, then during translation of the knife blade through the knife channel, the knife blade may contact the knife channel, which, in turn, may lead to tissue not being effectively severed. 
         [0006]    In addition to electrosurgical instruments, ultrasonic instruments may be utilized to treat tissue. Conventional ultrasonic instruments, e.g., an ultrasonic dissector, typically include an end effector assembly including jaw members configured to manipulate tissue (e.g., grasp and seal tissue). Typically, the ultrasonic dissector utilizes both mechanical clamping action and ultrasonic energy to effect hemostasis by heating the tissue and blood vessels to coagulate, cauterize, seal, cut, dissect, desiccate, and/or fulgurate tissue. While ultrasonic instruments may effectively treat and, subsequently, dissect tissue, ultrasonic instruments are typically not configured to articulate and/or “flex.” As can be appreciated, this limits their use in the surgical environment. 
       SUMMARY 
       [0007]    The present disclosure provides an end effector assembly for an electrosurgical instrument. The end effector assembly has a pair of first and second jaw members including respective seal plates having a width. Each of the seal plates is adapted to connect to an energy source. One or both of the first and second jaw members may be movable relative to the other jaw member from an open position, wherein the first and the second jaw members are disposed in spaced relation relative to one another, to a clamping position, wherein the first and second jaw members cooperate to grasp tissue therebetween. The first and second jaw members are operable in two modes of operation, a first mode of operation for treating tissue and a second mode of operation for separating tissue. The seal plate of the first jaw member includes a width that is smaller than a width of the seal plate of the second jaw member. In the second mode of operation, the seal plate of the first jaw member is independently activatable from the seal plate of the second jaw member to facilitate the separation of tissue when the first and second jaw members are in one of the open and clamping positions. 
         [0008]    The present disclosure provides a system for performing an electrosurgical procedure. The system includes an energy source that is configured to function in two or more modes of operation, a first mode of operation for treating tissue and a second mode of operation for dissecting tissue. The system includes an electrosurgical forceps that includes a handle having a shaft that extends therefrom and defines a longitudinal axis therethrough. An end effector assembly operatively connected to a distal end of the shaft and has a pair of first and second jaw members including respective seal plates having a width. Each of the seal plates is adapted to connect to an energy source. One or both of the first and second jaw members are movable relative to the other jaw member from an open position, wherein the first and the second jaw members are disposed in spaced relation relative to one another, to a clamping position, wherein the first and second jaw members cooperate to grasp tissue therebetween. The first and second jaw members are operable the first mode of operation for treating tissue and the second mode of operation for separating tissue. The seal plate of the first jaw member includes a width that is smaller than a width of the seal plate of the second jaw member. In the second mode of operation, the seal plate of the first jaw member is independently activatable from the seal plate of the second jaw member to facilitate the separation of tissue when the first and second jaw members are in one of the open and clamping positions. 
         [0009]    The present disclosure also provides a method for performing an electrosurgical procedure. The method includes positioning tissue between first and second jaw members of an electrosurgical instrument. The first and second jaw members are operable in two modes of operation, a first mode of operation for treating tissue and a second mode of operation for separating tissue. The seal plate of the first jaw member includes a width that is smaller than a width of the seal plate of the second jaw member. The method includes closing the first and second jaw members such that the tissue is clamped therebetween. Transmitting electrosurgical energy in the first mode of operation to the first and second jaw members for electrosurgically treating tissue is a step of the method. And, transmitting electrosurgical energy in the second mode of operation to the seal plate of the first jaw member for dissecting the electrosurgically treated tissue is another step of the method. 
         [0010]    In an embodiment, in the second mode of operation, the seal plate of the first jaw member is independently activatable from the seal plate of the second jaw member to facilitate the separation of tissue when the first and second jaw members are in one of the open and clamping positions. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    Embodiments of the presently disclosed specimen retrieval apparatus are described hereinbelow with reference to the drawings wherein: 
           [0012]      FIG. 1  is a left, perspective view of an electrosurgical instrument including an end effector having jaw members according to an embodiment of the present disclosure; 
           [0013]      FIG. 2  is an enlarged, left perspective view of the indicated area of detail of  FIG. 1  with a dissecting jaw member adjacent tissue; 
           [0014]      FIGS. 3A-3C  are front views of the jaw members depicted in  FIG. 2  illustrating various alignment configurations thereof; 
           [0015]      FIG. 4  is side view of jaw members depicted in  FIG. 2  with tissue positioned across the dissecting jaw member; and 
           [0016]      FIG. 5  is side view of jaw members depicted in  FIG. 2  with tissue positioned across the dissecting jaw member with the jaw members in a clamping position. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0017]    Detailed embodiments of the present disclosure are disclosed herein; however, the disclosed embodiments are merely examples of the disclosure, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure. 
         [0018]    Turning now to  FIGS. 1-4 , and initially with reference to  FIG. 1 , an electrosurgical instrument, e.g., an electrosurgical forceps  10  (forceps  10 ), that includes an end effector  100  according to an embodiment of the present disclosure is shown. Forceps  10  is operatively and selectively coupled to an electrosurgical generator (generator “G”) for performing an electrosurgical procedure ( FIG. 1 ). In some instances, the forceps  10  may be battery-powered. For purposes herein, an electrosurgical procedure may include sealing, cutting, dissecting, cauterizing, coagulating, desiccating, and/or fulgurating tissue all of which may employ RF energy. The generator “G” is configured for monopolar and bipolar modes of operation. The generator “G” may include or is in operative communication with a control system “CS” ( FIG. 1 ) that may include one or more processors in operative communication with one or more control modules that are executable on the processor. The control module (not explicitly shown) may be configured to instruct one or more modules to transmit electrosurgical energy, which may be in the form of a wave or signal/pulse, via one or more cables (e.g., a cable  310 ) to one or both jaw members  110  and  120  of an end effector  100 . 
         [0019]    Briefly, forceps  10  is configured for use with various surgical procedures and includes a housing  20 . A shaft  12  extends distally from the housing  20  and defines a longitudinal axis “A-A” therethrough. In the drawings and in the descriptions that follow, the term “proximal,” as is traditional, will refer to the end of the forceps  10  that is closer to the user, while the term “distal” will refer to the end that is farther from the user. The shaft has a distal end  16  configured to mechanically engage the end effector assembly  100  and a proximal end  14  that mechanically engages the housing  20 . In certain instances, the shaft  12  may be configured to bend or articulate. For example, shaft  12  may be resilient or portion thereof may include an articulating member. 
         [0020]    A handle assembly  30  includes a fixed handle  50  and a movable handle  40 . Fixed handle  50  is integrally associated with housing  20  and handle  40  is movable relative to fixed handle  50 . In certain embodiments, movable handle  40  of handle assembly  30  may be operably coupled to a drive assembly (not shown), which together may be configured to cooperate to impart movement of one or both of jaw members  110  and  120  to move from an open position, wherein the jaw members  110  and  120  are disposed in spaced relation relative to one another, to a clamping or closed position, wherein the jaw members  110  and  120  cooperate to grasp tissue therebetween. Although the figure drawings depict a forceps  10  for use in connection with endoscopic surgical procedures, the present disclosure may be used for more traditional open surgical procedures. The open version of the forceps may also include the same or similar operating components and features as described below. 
         [0021]    For a more detailed description of the housing  20 , shaft  20 , handle assembly  30  (including movable and fixed handles  40  and  50 , respectively), rotating assembly  80 , trigger assembly  70  and electrosurgical cable  310  (including line-feed configurations and/or connections), reference is made to commonly-owned U.S. Pat. No. 7,150,097 to Sremcich filed Jun. 13, 2003. 
         [0022]    With continued reference to  FIG. 1 , one or more buttons or switches  60  are operably disposed on the forceps  10 . More particularly, and in the illustrated embodiment, two switches “D” and “S” are shown operably disposed on the fixed handle  50 . In certain embodiments, it may prove advantageous to provide the switches  60  on the generator “G”. This of course will depend on the contemplated uses of a manufacturer. Switches “D” and “S” are in operative communication with the generator “G” and/or control system “CS” and are configured to place the forceps  10  in one or more modes of operation. More particularly, switch “S” is configured to place the forceps  10  in a first mode of operation for treating tissue, e.g., sealing tissue, and switch “D” is configured to place the forceps  10  in a second mode of operation for separating tissue, e.g., dissecting tissue. 
         [0023]    In the first mode of operation the generator “G” including control system “CS” and the forceps  10  are configured to fuse, seal, coagulate and/or fulgurate tissue. To this end, the jaw members  110  and  120  are configured to function in a bipolar mode of operation. That is, respective seal plates  118  and  128  of jaw members  110  and  120  are both active, include opposing polarities and are configured to transmit electrosurgical energy, e.g., current, therebetween. In the second mode of operation the generator “G” including control system “CS” and the forceps  10  are configured to dissect, cut, severe and/or transect tissue. To this end, the jaw members  110  and  120  are configured to function in a monopolar mode of operation. That is, seal plate  128  is active, seal plate  118  is inactive or neutral (and/or is highly resistive to current flow), and seal plate  128  is configured to transmit electrosurgical energy, e.g., current, to tissue. In the monopolar mode of operation, a return pad or electrode is positioned on a patient and is configured to provide a return path for the current back to the generator “G”. 
         [0024]    With reference to  FIG. 2 , an embodiment of end effector assembly  100  including jaw members  110  and  120  is illustrated. In the illustrated embodiment, jaw members  110  and  120  are of the unilateral type. That is, jaw member  110  is movable, e.g., pivotable, with respect to jaw member  120 . Alternatively, jaw members  110  and  120  may be of the bilateral type. That is, each of the jaw members  110  and  120  are movable with respect to each other, In an embodiment, to facilitate pivoting the jaw member  110  with respect to jaw member  120 , a pivot pin  103  couples the jaw members  110  and  120  to the distal end  16  of the shaft  12 , as best seen in  FIG. 2 . Jaw members  110  and  120 , and operative components associated therewith, may be formed from any suitable material, including but not limited to metal, metal alloys, plastic, plastic composites, and so forth. 
         [0025]    Continuing with reference to  FIG. 2 , jaw member  110  is shown including a jaw housing  117  having a width of suitable proportion, i.e., a width that is suitable to support the seal plate  118 . Electrically conductive seal plate  118  is operably supported on and secured to jaw housing  117 . More particularly, a distal end  117   a  of jaw member  110  may be configured to securely engage the electrically conductive seal plate  118  or, with respect to a monolithic jaw member, form the seal plate  118 . 
         [0026]    One or more insulative or non-conductive standoffs  113  (one insulative standoff is shown) made of any suitable material, e.g., plastic, ceramic, etc., is operably disposed on the seal plate  118 . More particularly, the insulative standoff  113  is operably disposed on a seal surface of the seal plate  118  at a distal end thereof; as best seen in  FIG. 2 . Insulative standoff  113  may be secured to the seal surface of the seal plate  118  by one or more suitable securement methods, e.g., an adhesive. In the illustrated embodiment, a “pocket” is etched in the seal surface during the manufacture process thereof, a bead of adhesive is placed in the “pocket” and the insulative standoff  113  is positioned therein. Other securement methods are contemplated. 
         [0027]    The insulative standoff  113  is configured to contact a distal tip of the seal plate  128  when the jaw members  110  and  120  are in the clamping position such that a gap distance of suitable proportion is present between the seal surface of the seal plate  118  and a seal surface of a seal plate  128  of the jaw member  120 . As a result thereof, the jaw members  118  and  128  only contact at their respective tips. Having the insulative standoff  113  positioned at the distal end of the seal plate minimizes any negative effects that may be associated with a non-conductive member being positioned on the seal surface of the seal plate  128 . That is, having a portion of the seal surface of the seal plate  118  that does not conduct electrosurgical energy may compromise a tissue seal, e.g., the tissue seal may not be uniform and/or consistent across a length thereof. A uniform and/or consistent tissue seal is important, especially in the instance where one jaw member, e.g., jaw member  120 , includes a seal plate  128  having a width that is smaller or “finer” than the other seal plate, e.g., seal plate  118 . That is, the width of the tissue seal achieved with the jaw members  110  and  120  of the present disclosure is smaller (and thus the overall area of the tissue seal is smaller) than widths of tissue seals typically achieved by conventional jaw members. 
         [0028]    Unlike conventional electrosurgical forceps that include end effectors having jaw members with seal plates having the same width, seal plates  118  and  128  of respective jaw members  110  and  120  of end effector  100  have different widths. More particularly, to facilitate separating tissue during the second mode of operation, the seal plate  128  of the jaw member  120  includes a width that is small in comparison to the width of the seal plate  118  of the jaw member  110 . That is, seal plate  128  of the jaw member  120  is smaller or “finer” than the jaw member seal plate  118  of the  110  (see  FIG. 2  in combination with  FIGS. 3A-3C ). For illustrative purposes, a width of the jaw housing  127  of the jaw member  120  is also illustrated as being smaller than a width of the jaw housing  117  of the jaw member  110 . In some embodiments, it may prove advantageous to have the jaw housing  117  and  127  with the same widths and the seal plates  118  and  128  with different widths. The specific configuration, e.g., widths, of the jaw housing  117  and  127  may be varied for a specific surgical procedure, specific manufacturer requirement, etc. In accordance with an embodiment of the present disclosure, seal plate  118  of the jaw member  110  (the larger jaw) includes a width that is approximately 1 mm to 2 mm larger than the width of the seal plate  128  of the jaw member  120  (the smaller or “finer” jaw member). Keeping the width of the seal plate  128  1 mm to 2 mm smaller than the width of the seal plate  117  improves visualization and dissection capabilities for the end user, e.g., a surgeon. In the illustrated embodiment, seal plate  128  of the jaw member  120  includes a width that ranges from about 1 mm to about 3.4 mm and seal plate  118  of the jaw member  120  includes a width that ranges from about 3.5 mm to about 5 mm. 
         [0029]    Similar to jaw member  110 , jaw member  120  includes a jaw housing  127  having a distal end  127   a  that is configured to support seal plate  128  ( FIG. 2 ). Unlike jaw member  110 , jaw member  120  includes a seal plate  128  that includes a peripheral edge  121  that extends along a side surface of the jaw housing  127  to a distal tip  123  thereof, see  FIGS. 2 ,  4  and  5 . The peripheral edge  121  including the distal tip  123  is configured to separate tissue, e.g., dissect tissue, when the jaw members  110  and  120  are in either the open position ( FIGS. 2 and 4 ) or the closed position ( FIG. 5 ) and when tissue is positioned adjacent thereto. More particularly, and in one particular embodiment, when switch “D” is activated, the forceps  10  is configured to operate in the second mode of operation, e.g., a monopolar mode of operation. In the second mode of operation, the generator “G” transmits electrosurgical energy to the seal plate  128  including the peripheral edge  121  and the distal tip  123  such that a user may dissect tissue that has been electrosurgically treated. 
         [0030]    Referring to  FIGS. 3A-3C , to facilitate treating and/or separating tissue, jaw members  110  and  120  may be aligned along their center lines, i.e., centrally aligned along a common axis, e.g., longitudinal axis “A-A” ( FIGS. 2 and 3A ); aligned along a right or left portion of the peripheral edge  121  ( FIG. 3B ); or aligned somewhere therebetween ( FIG. 3C ). In the illustrated embodiment, the jaw members  110  and  120  are centrally aligned along the longitudinal axis “A-A,” as best seen in  FIGS. 2 and 3A . Alignment along the longitudinal axis “A-A” facilitates dissecting tissue from either side of the forceps  10 . In the embodiment where jaw members  110  and  120  are aligned along the right or left portion the peripheral edge  121  (see  FIG. 3B  where the jaw members  110  and  120  are aligned the left portion of the peripheral edge), the peripheral edge  121  includes an inner edge  121   a  that is configured to decrease current densities thereabout for either fusing, sealing, coagulating or fulgurating tissue during the first mode and an outer edge  121   b  that is configured to increase current densities thereabout for either dissecting, cutting, severing or transecting tissue during the second mode. With these purposes in mind, inner edge  121   a  includes a radius that is larger than a radius of the outer edge  121   b , as best seen in  FIG. 3B   
         [0031]    As can be appreciated, in any of the foregoing alignment configurations of the jaw members  110  and  120 , the peripheral edge  121  (and/or edges  121   a  and  121   b ) may include radii dimensioned to accommodate a specific surgical procedure, specific manufacturer preference, etc. 
         [0032]    Operation of forceps  10  is described in terms of use of a method for electrosurgically treating tissue, such as, for example, during a hysterectomy, a colectomy and/or a Nissen fundoplication, commonly referred to in the art as a lap Nissen. Initially, the forceps  10  is inserted through an incision in a patient. Tissue is positioned between the jaw members  110  and  120 . In the instance where a user wants to seal tissue, the user activates switch “S.” Activation of switch “S” indicates to the generator “G” and/or control system “CS” that the jaw members  110  and  120  are ready to operate in the bipolar mode of operation. Thereafter, generator “G” delivers electrosurgical energy to the respective seal plates  118  and  128  of the jaw members  110  and  120  to seal tissue positioned between the jaw members  110  and  120 . 
         [0033]    To dissect tissue, a user activates switch “D.” Activation of switch “D” indicates to the generator “G” and/or control system “CS” that the jaw members  110  and  120  are ready to operate in the monopolar mode of operation. A return pad or electrode may be positioned (at some time prior to operation of the forceps  10  in the monopolar mode) on the patient and functions as described above. Alternatively, an in some embodiments, the seal plate  118  may function as the return pad. In the monopolar mode of operation, generator “G” delivers electrosurgical energy to the seal plate  128  including the peripheral edge  121  and the distal tip  123  to dissect the electrosurgically treated tissue. During dissection, the jaw members  110  and  120  may be in either the open or closed position. Moreover, any portion of the seal plate  128  and/or the peripheral edge  121  including the distal tip  123  may be utilized to dissect the electrosurgically treated tissue. 
         [0034]    For example, and in one particular surgical scenario, the jaw members  110  and  120  may be in the open position and the distal tip  123  may utilized to dissect the electrosurgically treated tissue. In this instance, the distal tip  123  is positioned adjacent tissue and moved in a direction indicated by directional arrow “M” into the tissue with a force of suitable proportion while simultaneously energizing the seal plate  128  ( FIG. 2 ). 
         [0035]    In another surgical scenario, the jaw members  110  and  120  may be in the open position and seal plate  128  may be utilized to dissect the electrosurgically treated tissue. In this instance, the seal plate  128  is positioned adjacent tissue and moved in a direction indicated by directional arrow “N” across the tissue with a force of suitable proportion while simultaneously energizing the seal plate  128  ( FIG. 4 ). 
         [0036]    In yet another surgical scenario, the jaw members  110  and  120  may be, initially, in the open position and seal plate  128  may utilized to dissect the electrosurgically treated tissue. In this instance, the seal plate  128  is positioned adjacent tissue and moved in a direction indicated by directional arrow “O” across the tissue with a force of suitable proportion while simultaneously energizing the seal plate  128  and closing the jaw members  110  and  120  ( FIG. 5 ). 
         [0037]    The forceps  10  including the jaw members  110  and  120  overcome some of aforementioned shortcomings of the above-referenced electrosurgical and/or ultrasonic instruments. More particularly, providing the forceps  10  with the finer seal plate  128  having the peripheral edge  121  eliminates the need for a knife blade and components associated therewith to dissect tissue. As can be appreciated, this lowers manufacturing costs of the forceps  10  and/or decreases or eliminates the manufacturing tolerances that are typically associated with conventional forceps. Moreover, while not discussed in great detail, the shaft  12  may be configured to bend or articulate; this provides a surgeon with greater flexibility with respect to treating and/or dissecting tissue when compared to ultrasonic instruments. 
         [0038]    From the foregoing and with reference to the various figure drawings, those skilled in the art will appreciate that certain modifications can also be made to the present disclosure without departing from the scope of the same. For example, in certain embodiment it may prove useful to have one or both of the seal plates  118  and  128  with a textured or otherwise treated seal surface. 
         [0039]    It is contemplated that rather than configuring one of the seal plates  118  and  128  to dissect tissue, a separate or additional device may be utilized to dissect tissue. For example, one or both of the jaw members  110  and  120  may include a second or auxiliary conductive surface. More particularly, a conductive surface (not shown) of suitable proportion may be operably disposed on one or both of an exterior surface of the jaw housing  117  and  127 . For example, a conductive surface may extend along a length of a bottom exterior surface of the jaw housing  127  or a conductive surface may extend along a length of a top exterior surface of the jaw housing  117 . As can be appreciated, in either of these instances, the conductive surface is configured to function substantially similar to that of the seal plate  128  described above. 
         [0040]    It is contemplated that the generator “G” may be configured to automatically detect when to place the forceps  10  in either the first or second modes of operation. In this instance, switches  60  may be utilized in a limited capacity or eliminated altogether. 
         [0041]    While several embodiments of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.