Abstract:
An electrosurgical apparatus includes a housing having at least one shaft extending therefrom that defines a longitudinal axis therethrough. The shaft operatively supports an end effector assembly at a distal end thereof. The end effector assembly includes first and second jaw members pivotably connected to each other and moveable from an open spaced apart position to a closed position to grasp tissue. An electrically conductive tissue sealing plate is operatively coupled to each of the jaw members. At least one of the jaw members has a serrated edge disposed thereon for selectively sectioning tissue upon rotation of the end effector assembly about the longitudinal axis. The electrically conductive tissue sealing plates are adapted to connect to an electrosurgical energy source. The electrosurgical apparatus operably communicates with a control system configured to regulate the delivery of electrosurgical energy from the source of electrosurgical energy to the electrically conductive tissue sealing plate on each of the jaw members.

Description:
BACKGROUND 
     1. Technical Field 
     The following disclosure relates to an apparatus, system, and method for performing an electrosurgical procedure and, more particularly, to an apparatus, system and method that utilizes energy to cut and/or section tissue. 
     2. Description of Related Art 
     It is well known in the art that electrosurgical generators are employed by surgeons in conjunction with electrosurgical instruments to perform a variety of electrosurgical surgical procedures (e.g., tonsillectomy, adenoidectomy, etc.). An electrosurgical generator generates and modulates electrosurgical energy which, in turn, is applied to the tissue by an electrosurgical instrument. Electrosurgical instruments may be either monopolar or bipolar and may be configured for open or endoscopic procedures. 
     Electrosurgical instruments may be implemented to ablate, seal, cauterize, coagulate, and/or desiccate tissue and, if needed, cut and/or section tissue. Typically, cutting and/or sectioning tissue is performed with a knife blade movable within a longitudinal slot located on or within one or more seal plates associated with one or more jaw members configured to receive a knife blade, or portion thereof. The longitudinal slot is normally located on or within the seal plate within a treatment zone (e.g., seal and/or coagulation zone) associated therewith. Consequently, the knife blade cuts and/or sections through the seal and/or coagulation zone during longitudinal translation of the knife blade through the longitudinal slot. In some instances, it is not desirable to cut through the zone of sealed or coagulated tissue, but rather to the left or right of the zone of sealed or coagulated tissue such as, for example, during a tonsillectomy and/or adenoidectomy procedure. 
     SUMMARY 
     According to an embodiment of the present disclosure, an electrosurgical apparatus includes a housing having at least one shaft extending therefrom that defines a longitudinal axis therethrough. The shaft operatively supports an end effector assembly at a distal end thereof. The end effector assembly includes first and second jaw members pivotably connected to each other and moveable from an open spaced apart position to a closed position to grasp tissue. An electrically conductive tissue sealing plate is operatively coupled to each of the jaw members. At least one of the jaw members has a serrated edge disposed thereon for selectively sectioning tissue upon rotation of the end effector assembly about the longitudinal axis. The electrically conductive tissue sealing plates are adapted to connect to an electrosurgical energy source. The electrosurgical apparatus operably communicates with a control system configured to regulate the delivery of electrosurgical energy from the source of electrosurgical energy to the electrically conductive tissue sealing plate on each of the jaw members. 
     According to another embodiment of the present disclosure, an electrosurgical apparatus includes a housing having at least one shaft extending therefrom that defines a longitudinal axis therethrough. The shaft operatively supports an end effector assembly at a distal end thereof. The end effector assembly includes first and second jaw members pivotably connected to each other and moveable from an open spaced apart position to a closed position to grasp tissue. An electrically conductive tissue sealing plate is operatively coupled to each of the jaw members. At least one of the jaw members has a serrated edge disposed thereon for selectively sectioning tissue upon rotation of the end effector assembly about the longitudinal axis. The serrated edge is electrically insulated from the electrically conductive seal plates and includes a series of teeth disposed linearly along a periphery of at least one of the first and second jaw members. The electrically conductive tissue sealing plates are adapted to connect to an electrical surgical energy source. The electrosurgical apparatus operably communicates with a control system configured to regulate the delivery of electrosurgical energy from the source of electrosurgical energy to the electrically conductive tissue sealing plate on each of the jaw members. 
     The present disclosure also provides a method for performing an electrosurgical procedure. The method includes the initial step of providing an electrosurgical apparatus. The electrosurgical apparatus includes a housing having at least one shaft extending therefrom that defines a longitudinal axis therethrough. The shaft operatively supports an end effector assembly at a distal end thereof. The end effector assembly includes first and second jaw members pivotably connected to each other and moveable from an open spaced apart position to a closed position to grasp tissue. An electrically conductive tissue sealing plate is disposed on each of the jaw members. At least one of the jaw members has a serrated edge disposed thereon for selectively sectioning tissue. The bipolar forceps operably communicates with a control system configured to regulate the delivery of electrosurgical energy from the source of electrosurgical energy to the electrically conductive tissue sealing plate on each of the jaw members. The method also includes the step of delivering electrosurgical energy from the source of electrosurgical energy to each of the electrically conductive tissue sealing plates to achieve a desired tissue effect. The method also includes the step of applying a rotational force to the end effector assembly about the longitudinal axis such that the serrated edge engages at least a portion of the effected tissue to facilitate selective separation of at least a portion of the effected tissue from the rest of the effected tissue. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       Various embodiments of the present disclosure are described hereinbelow with references to the drawings, wherein: 
         FIG. 1A  is a perspective view of an electrosurgical apparatus and electrosurgical generator according to an embodiment of the present disclosure; 
         FIG. 1B  is an additional perspective view of the electrosurgical apparatus and electrosurgical generator of  FIG. 1A ; 
         FIG. 1C  is an enlarged view of the indicated area of detail shown in  FIG. 1A ; 
         FIG. 1D  is an enlarged view of the indicated area of detail shown in  FIG. 1C ; 
         FIG. 2  is a block diagram illustrating components of the system of  FIGS. 1A and 1B ; 
         FIG. 3  is a schematic representation of an electrical configuration for connecting the electrosurgical apparatus to the electrosurgical generator depicted in  FIGS. 1A and 1B ; 
         FIGS. 4A and 4B  illustrate the electrosurgical apparatus depicted in  FIGS. 1A and 1B  in use; and 
         FIG. 5  is a flowchart of a method for performing an electrosurgical procedure according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Detailed embodiments of the present disclosure are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary 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. 
     With reference to  FIGS. 1A and 1B , bipolar forceps  10  is shown for use with various electrosurgical procedures and generally includes a housing  20 , a handle assembly  30 , a rotating assembly  80 , a trigger assembly  70 , a shaft  12 , a drive rod  130  (shown in phantom), and an end effector assembly  100  having jaw members  110 ,  120  that mutually cooperate to grasp, seal and divide large tubular vessels and large vascular tissues. Jaw members  110 ,  120  include spring-like cantilever arms  112   a ,  112   b , respectively, at a distal end thereof. Cantilever arms  112   a ,  112   b  normally bias jaw members  110 ,  120  in an open position wherein jaw members  110 ,  120  are disposed in spaced relation relative to one another, as best shown in  FIG. 1A . Although the majority of the figure drawings depict a bipolar forceps  10  for use in connection with endoscopic surgical procedures, the present disclosure may be used for more traditional open surgical procedures. 
     Shaft  12  has a distal end  16  dimensioned to mechanically engage the end effector assembly  100  and a proximal end  14  that mechanically engages the housing  20 . In the drawings and in the descriptions which follow, the term “proximal,” as is traditional, will refer to the end of the forceps  10  which is closer to the user, while the term “distal” will refer to the end which is farther from the user, 
     Drive rod  130  is slidably disposed in shaft  12 . A proximal end of drive rod  130  is operatively coupled to handle assembly  30  and a distal end of drive rod  130  is operatively coupled to end effector assembly  100 . More specifically, cantilever arms  112   a  and  112   b  are anchored at a proximal end to a distal end of drive rod  130 , as best shown in  FIG. 1C . 
     The proximal end of drive rod  130  is operatively coupled to handle assembly  30  such that actuation of moveable handle  40  toward stationary handle  50  imparts proximal movement of drive rod  130 , which, in turn, urges end effector assembly  100  proximally whereby the distal end  16  of shaft  12  operates as a collet, engaging cantilever arms  112   a  and  112   b  to force jaw members  110 ,  120  to a clamped or closed position wherein jaw members  110 ,  120  cooperate to grasp tissue therebetween, as best shown in  FIG. 1B . Movement of moveable handle  40  away from stationary handle  50  imparts distal movement of drive rod  130 , which, in turn, urges end effector assembly  100  distally such that cantilever arms  112   a  and  112   b  disengage the distal end  16  of shaft  12  to allow movement of jaw members  110 ,  120  to an open position wherein jaw members  110 ,  120  are disposed in spaced relation relative to one another, as best shown in  FIG. 1A . 
     In other embodiments, actuation of moveable handle  40  toward stationary handle  50  may be configured to impart distal movement of drive rod  130  and actuation of moveable handle away from stationary handle  50  may be configured to impart proximal movement of drive rod  50 . 
     In embodiments, the proximal end  14  of shaft  12  is operatively coupled to handle assembly  30  to facilitate functionality substantially as described above with respect to drive rod  130 . More specifically, proximal and distal movement of shaft  12  relative to drive rod  130  may be imparted via actuation of moveable handle  40  away from or toward stationary handle  50 , respectively, or vice-versa. In this scenario, distal movement of shaft  12  causes the distal end  16  of shaft  12  to engage cantilever arms  11   2   a  and  11   2   b  to move jaw members  110 ,  120  to a clamped or closed position wherein jaw members  110 ,  120  cooperate to grasp tissue therebetween, as best shown in  FIG. 1B  Proximal movement of shaft  12  causes the distal end  16  of shaft to disengage cantilever arms  112   a  and  112   b  to allow movement of jaw members  110 ,  120  to an open position wherein jaw members  110 ,  120  are disposed in spaced relation relative to one another, as best shown in  FIG. 1A . 
     Forceps  10  includes an electrosurgical cable  410  that connects the forceps  10  to a source of electrosurgical energy, e.g., generator  200 , shown schematically in  FIG. 1 . As shown in  FIG. 3 , cable  410  is internally divided into cable leads  410   a ,  410   b  and  425   b  that are designed to transmit electrical potentials through their respective feed paths through the forceps  10  to the end effector assembly  100 . 
     For a more detailed description of handle assembly  30 , movable handle  40 , rotating assembly  80 , and electrosurgical cable  410  (including line-feed configurations and/or connections) reference is made to commonly owned Patent Publication No., 2003-0229344, filed on Feb. 20, 2003, entitled VESSEL SEALER AND DIVIDER AND METHOD OF MANUFACTURING THE SAME. 
     As noted above, movable handle  40  of handle assembly  30  operatively couples to a drive rod  130  which, together, mechanically cooperate to impart movement of the jaw members  110  and  120  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. 
     Jaw members  110 ,  120  include an insulative jaw housing  117  and electrically conductive seal plates  118 ,  128 , respectively. Insulator  117  is configured to securely engage the electrically conductive seal plates  118 ,  128 . Seal plates  118 ,  128  may be manufactured from stamped steel. This may be accomplished by stamping, by overmolding, by overmolding a stamped electrically conductive sealing plate and/or by overmolding a metal injection molded seal plate. All of these manufacturing techniques produce an electrode having a seal plate  118  that is substantially surrounded by the insulating substrate. 
     One of the jaw members  110  includes a plurality of teeth or a serrated edge  122  configured to facilitate secure grasping of tissue between jaw members  110 ,  120  and, further, for separating or severing tissue, as will be discussed in further detail below. Serrated edge  122  may be a series of teeth  122   a  disposed linearly about a periphery of either or both jaw members  110 ,  120 . Serrated edge  122  is configured such that teeth  122   a  of serrated edge  122  are disposed on a surface normal to an inner surface of a jaw member and protrude toward the opposing jaw member. As best shown in  FIG. 1D , the teeth  122   a  each include a pair of base sides  124   b  that meet to form a pointed tip  124   b  at am adjoining apex. Either or both pointed tips  124   b  and base sides  124   b  of each tooth  122   a  may be suitably sharpened to facilitate separation of tissue. 
     Jaw members  110 ,  120  may include a protective shield (not explicitly shown) disposed about an outer surface of serrated edge  122  to prevent contact between the outer surface of serrated edge  122  and an operator&#39;s hand. In this scenario, the inner surface of serrated edge  122  remains exposed for facilitating grasping and/or separation of tissue. A protective shield for this purpose may be formed of a suitable material such as, for example, a plastic material, a metal material having an insulated surface, or the like. Serrated edge  122 , as depicted in the figures, is illustrative only in that either or both jaw members  110 ,  120  may include one or more serrated edges to facilitate grasping and/or separating of tissue. 
     To prevent short-circuiting from occurring between the serrated edge  122  and the seal plate adjacent thereto (e.g., seal plate  118 ), serrated edge  122  may be provided with an insulative material (not explicitly shown) applied thereto. Alternatively, or in addition thereto, the portion of the serrated edge  122  that is adjacent to the seal plate may be made from a non-conductive material. 
     With continued reference to  FIGS. 1A and 1B , an illustrative embodiment of an electrosurgical generator  200  (generator  200 ) is shown. Generator  200  is operatively and selectively connected to bipolar forceps  10  for performing an electrosurgical procedure. As noted above, an electrosurgical procedure may include sealing, cutting, coagulating, desiccating, and fulgurating tissue all of which may employ RF energy. Generator  200  may be configured for monopolar and/or bipolar modes of operation. Generator  200  includes all necessary components, parts, and/or members needed for a control system  300  (system  300 ) to function as intended. Generator  200  generates electrosurgical energy, which may be RF (radio frequency), microwave, ultrasound, infrared, ultraviolet, laser, thermal energy or other electrosurgical energy. An electrosurgical module  220  generates RF energy and includes a power supply  250  for generating energy and an output stage  252  which modulates the energy that is provided to the delivery device(s), such as an end effector assembly  100 , for delivery of the modulated energy to a patient. Power supply  250  may be a high voltage DC or AC power supply for producing electrosurgical current, where control signals generated by the system  300  adjust parameters of the voltage and current output, such as magnitude and frequency. The output stage  252  may modulate the output energy (e.g., via a waveform generator) based on signals generated by the system  300  to adjust waveform parameters, e.g., waveform shape, pulse width, duty cycle, crest factor, and/or repetition rate. System  300  may be coupled to the generator module  220  by connections that may include wired and/or wireless connections for providing the control signals to the generator module  220 . 
     With reference to  FIG. 2 , system  300  is configured to, among other things, analyze parameters such as, for example, power, tissue temperature, current, voltage, impedance, etc., such that a proper tissue effect can be achieved. System  300  includes one or more processors  302  in operative communication with a control module  304  executable on the processor  302 , and is configured to, among other things, quantify electrical and thermal parameters during tissue sectioning such that when a threshold value for electrical and thermal parameters is met, the control system  300  provides a signal to a user to apply a force to tissue. Control module  304  instructs one or more modules (e.g., an output module  306 ) to transmit electrosurgical energy, which may be in the form of a wave or signal/pulse, via one or more cables (e.g., cable  410 ) to one or both of the seal plates  118 ,  128 . Electrosurgical energy may be transmitted to each of the seal plates  118 ,  128  simultaneously or consecutively. 
     One or both of the jaw members  110 , 120  may include one or more sensors  316 . Sensors  316  are placed at predetermined locations on, in, or along surfaces of the jaw members  110 ,  120 . In embodiments, end effector assembly  100  and/or jaw members  110  and  120  may have sensors  316  placed near a proximal end and/or near a distal end of jaw members  110  and  120 , as well as along the length of jaw members  110  and  120 . 
     The control module  304  processes information and/or signals (e.g., tissue impedance and/or tissue temperature data from sensors  316 ) input to the processor  302  and generates control signals for modulating the electrosurgical energy in accordance with the input information and/or signals. Information may include pre-surgical data (e.g., tissue temperature threshold values) entered prior to the electrosurgical procedure or information entered and/or obtained during the electrosurgical procedure through one or more modules (e.g., OM module  306 ) and/or other suitable device(s). The information may include requests, instructions, ideal mapping(s) (e.g., look-up-tables, continuous mappings, etc.), sensed information and/or mode selection. 
     The control module  304  regulates the generator  200  (e.g., the power supply  250  and/or the output stage  252 ) which adjusts various parameters of the electrosurgical energy delivered to the patient (via one or both of the seal plates) during the electrosurgical procedure. Parameters of the delivered electrosurgical energy that may be regulated include voltage, current, resistance, intensity, power, frequency, amplitude, and/or waveform parameters, e.g., waveform shape, pulse width, duty cycle, crest factor, and/or repetition rate of the output and/or effective energy. 
     The control module  304  includes software instructions executable by the processor  302  for processing algorithms and/or data received by sensors  316 , and for outputting control signals to the generator module  220  and/or other modules. The software instructions may be stored in a storage medium such as a memory internal to the processor  302  and/or a memory accessible by the processor  302 , such as an external memory, e.g., an external hard drive, floppy diskette, CD-ROM, etc. 
     The control module  304  regulates the electrosurgical energy in response to feedback information, e.g., information related to tissue condition at or proximate the surgical site. Processing of the feedback information may include determining: changes in the feedback information; rate of change of the feedback information; and/or relativity of the feedback information to corresponding values sensed prior to starting the procedure (pre-surgical values) in accordance with the mode, control variable(s) and ideal curve(s) selected. The control module  304  then sends control signals to the generator module  220  such as for regulating the power supply  250  and/or the output stage  252 . 
     Regulation of certain parameters of the electrosurgical energy may be based on a tissue response such as recognition that a proper seal is achieved and/or when a predetermined threshold temperature value is achieved. Recognition of the event may automatically switch the generator  200  to a different mode of operation (e.g., “stand by” mode or “RF output mode”) and subsequently switch the generator  200  back to an original mode after the event has occurred. In embodiments, recognition of the event may automatically switch the generator  200  to a different mode of operation and subsequently shutoff the generator  200 . 
     OM  306  (shown as two modules for illustrative purposes) may be digital and/or analog circuitry that can receive instructions from and provide status to a processor  302  (via, for example, a digital-to-analog or analog-to-digital converter). OM  306  is also coupled to control module  304  to receive one or more electrosurgical energy waves at a frequency and amplitude specified by the processor  302 , and/or transmit the electrosurgical energy waves along the cable  410  to one or both of the seal plates  118 ,  128 . OM  306  can also amplify, filter, and digitally sample return signals received by sensors  316  and transmitted along cable  410 . 
     A sensor module  308  senses electromagnetic, electrical, and/or physical parameters or properties at the operating site and communicates with the control module  304  and/or OM module  306  to regulate the output electrosurgical energy. The sensor module  308  may be configured to measure, i.e., “sense”, various electromagnetic, electrical, physical, and/or electromechanical conditions, such as at or proximate the operating site, including: tissue impedance, tissue temperature, and so on. For example, sensors of the sensor module  308  may include sensors  316 , such as, for example, optical sensor(s), proximity sensor(s), pressure sensor(s), tissue moisture sensor(s), temperature sensor(s), and/or real-time and RMS current and voltage sensing systems. The sensor module  308  measures one or more of these conditions continuously or in real-time such that the control module  304  can continually modulate the electrosurgical output in real-time. 
     In embodiments, sensors  316  may include a smart sensor assembly (e g., a smart sensor, smart circuit, computer, and/or feedback loop, etc. (not explicitly shown)). For example, the smart sensor may include a feedback loop which indicates when a tissue seal is complete based upon one or more of the following parameters: tissue temperature, tissue impedance at the seal, change in impedance of the tissue over time and/or changes in the power or current applied to the tissue over time. An audible or visual feedback monitor may be employed to convey information to the surgeon regarding the overall seal quality or the completion of an effective tissue seal. 
     With reference now to  FIGS. 4A and 4B , operation of bipolar forceps  10  under the control of system  300  is now described. For illustrative purposes, tissue division is described subsequent to the application of electrosurgical energy for achieving a desired tissue effect (e.g., tissue sealing). Control module  304  instructs one or more modules (e.g., an output module  306 ) to transmit electrosurgical energy, which may be in the form of a wave or signal/pulse, via one or more cables (e.g., cable  410 ) to one or both of the seal plates  118 ,  128  simultaneously or consecutively to effect a tissue seal. 
     Upon reaching a desired tissue seat result, control system  300  may indicate (by way of an audio or visual feedback monitor or indicator, previously mentioned and described above) to a user that tissue is ready for sectioning. A user may then rotate end effector assembly  100 , as indicated by rotational arrow “R”, in a clock-wise and/or counter clock-wise direction to cause serrated edge  122  to separate the tissue. For effective separation of tissue, the direction of rotation of end effector assembly  100  will depend on the positioning of the serrated edge  122  along either jaw member  110 ,  120 . Rotation of end effector assembly  100  may be achieved via, for example, use of rotation assembly  80  and/or movement of bipolar forceps  10  relative to the tissue to provide tension thereto. 
     As shown in the illustrated embodiment, a user may then grasp tissue (for example, with a surgical implement or suitable forceps  400 ) adjacent to the operating site and outside the seal zone ( FIG. 4A ) and apply a pulling force “F” generally normal and along the same plane as the sectioning line which facilitates the separation of tissue ( FIG. 4B ). Application of the pulling force “F” separates the unwanted tissue from the operating site with minimal impact on the seal zone. The remaining tissue at the operating site is effectively sealed and the separated tissue may be easily discarded. 
       FIG. 5  shows a method  500  for performing an electrosurgical procedure. At step  502 , an electrosurgical apparatus including a pair of jaw members configured to grasp tissue therebetween and including one or more serrated edges is provided. At step  504 , electrosurgical energy from an electrosurgical generator is directed through tissue held between the jaw members to effect a tissue seal. At step  506 , a rotational force is applied to the effected tissue site to facilitate separation of the tissue. 
     In embodiments, a force is applied to tissue adjacent the effected tissue site generally in a normal or transverse direction substantially simultaneously with or subsequent to step  508  to facilitate separation of the tissue. 
     In embodiments, step  506  may include the step of applying the rotational force substantially simultaneously with delivering electrosurgical energy from the source of electrosurgical energy to seal plates  118 ,  128 . 
     In embodiments, the step of applying a force may include the step of applying the force consecutively after audible or visible indication (e.g., a distinct audible tone, an illuminated LED on generator  200 ). 
     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.