Abstract:
A bipolar electrosurgical assembly is for use in female pelvic surgical procedures. A first shaft includes a uterine manipulator, a second shaft that fits over the first shaft includes a colpotomy cup and first and second electrodes, and a third shaft can be provided over the second shaft and carries a seal for maintaining pneumoperitoneum. The colpotomy cup uses the first and second electrodes for resecting uterine tissue. Incision and resection may be performed by positioning the colpotomy cup near the cervico-vaginal junction, activating the first electrode, and moving one or both of the electrodes.

Description:
BACKGROUND 
       [0001]    This disclosure relates to surgical instruments, and in particular to electrosurgical instruments utilized in total laparoscopic hysterectomy (TLH) procedures. 
         [0002]    Electrosurgical instruments used to resect a patient&#39;s cervix from the vagina are known. Such instruments generally carry out a number of functions: positioning of the uterus for resection, maintaining pneumoperitoneum during tissue resection, aiding in physician visibility during resection, and incision and resection of a patient&#39;s cervix from the vagina. It is known to provide a colpotomy device having an electrosurgical element and a uterine manipulator to aid in incising and positioning the uterus for resection. 
         [0003]    It is also known for the incision and resection to be performed by two electrosurgical instruments. Although one electrosurgical instrument may be introduced vaginally, at least one other electrosurgical instrument is typically introduced laparoscopically into the abdomen through a trocar or other similar device. 
         [0004]    In general, the incision and resection are performed by a single electrosurgical instrument. This is typically introduced laparoscopically into the abdomen through a trocar or other similar device. 
         [0005]    Instead of an electrosurgical instrument, mechanical cutting instruments such as scissors are sometimes used to form the incision. 
         [0006]    Some known electrosurgical instruments make use of a colpotomy cup in order to position and manipulate the uterus for resection. These can take many forms, but generally have a leading edge which fits at or near the cervico-vaginal junction. Colpotomy cups sometimes also carry a monopolar electrosurgical cutting instrument, either attached to the cup, or attached to another apparatus located near the patient&#39;s uterus. 
         [0007]    Monopolar devices exist for performing the incision to sever the cervix from the vagina. The active electrode performs the cutting in these configurations, with the return electrode placed elsewhere on the body. 
       SUMMARY 
       [0008]    Some electrosurgical devices used in TLH procedures make use of monopolar electrosurgical elements. Monopolar electrosurgical elements are used with a separate return electrode (for example, a return pad, grounding patch or neutral electrode) that is placed some distance away from the incision site. As a result of the distance between the return electrode and the incision site, monopolar electrosurgical elements typically exhibit poorer control over application of energy to the incision site. In particular, monopolar electrodes deliver less controllable pulses of energy and/or higher voltages, which can result in increased heat at the surgical site, and potentially damage other tissues, such as nerves, ureters or colon tissue near that site. A risk particular to TLH procedures is over-shortening of the vagina during resection of the cervix from the vagina. This can be caused, for example, by creating too much heat at the cutting device while performing the cervico-vaginal incision. Another potential complication related to creating too much heat during cutting is known as dehiscence. This occurs when the incised tissues that are brought together to close the vaginal canal with sutures during the procedure fail to fuse before the suture absorption period is reached. This is due to the heat damage to the tissue preventing the desired healing. 
         [0009]    A bipolar electrosurgical configuration reduces the risks associated with monopolar elements because a bipolar instrument has a shorter distance of electrical energy travel between the tissue to be excised and a return electrode. This enables the cutting energy to be more precisely focused. It also allows for lower cutting voltages to be used. 
         [0010]    In order to overcome difficulties inherent to the TLH procedure, namely, poor visibility, poor maneuverability, high degree of clinical skill needed, difficulty of incision, thermal damage at the vaginal cuff and the risks of damaging other organs, over-shortening the patient&#39;s vagina or risking future dehiscence, an aspect of the invention relates to a bipolar electrosurgical assembly that includes a colpotomy cup and first and second electrodes, one of which is an active electrode and one of which is a return electrode. In addition, the assembly preferably includes a uterine manipulator, to be used in tandem with the colpotomy cup for positioning of the uterus, and a seal for maintaining pneumoperitoneum. 
         [0011]    According to some embodiments, three shafts are utilized in the bipolar colpotomy assembly. The first shaft includes a uterine manipulator with a proximal end and a distal end. The second shaft is rotatably and slidably mounted over the first shaft, and preferably includes a control near its proximal end for controlling the colpotomy cup located near its distal end, and the first and second electrodes. A third shaft is rotatably and slidably mounted over the second shaft, and includes a seal for maintaining pneumoperitoneum. The seal can be, for example, a vaginal balloon, a foam plug, or malleable discs. During use, the colpotomy cup is placed at the cervico-vaginal junction, and a voltage differential can be applied between the electrodes in order to perform the incision, while the manipulator positions the cervix/uterus for resection and the seal maintains pneumoperitoneum. 
         [0012]    According to some embodiments, the first electrode and the second electrode are on a rim at the distal open end of the colpotomy cup. The first, active, electrode can be annular, and located in a radially outer position on the rim. The first electrode can be a solid ring, or made up of multiple arcs around the rim. The second, return electrode, can be located in a radially inner position along the rim. The incision at the cervico-vaginal junction can be performed by this embodiment in one of two ways: by emitting energy from the first electrode while longitudinally advancing the colpotomy cup, or by rotating the colpotomy cup while emitting energy from the first electrode. If cutting is to be performed in the first way, the colpotomy cup rim may have different heights (i.e., the rim of the cup may have undulations such that it is wavy) so that as it is advanced, the cutting voltage will be applied to different parts of the electrodes as those different parts come into contact with tissue. 
         [0013]    According to some embodiments, the first (active) electrode protrudes from the rim of the colpotomy cup, while the second electrode forms a ring around the rim of the colpotomy cup. In these embodiments, the second electrode may be annular along the inner portion of the rim of the colpotomy cup, and cover substantially the whole circumference of the rim, or any portion thereof. In embodiments where the first electrode is integral with and protrudes from the colpotomy cup, incision is performed by emitting energy from the first electrode while rotating the colpotomy cup, which rotates the first electrode. 
         [0014]    According to another embodiment, the first electrode is mounted on a spindle that rotates about the second shaft, and the second electrode is located along the distal edge of the colpotomy cup. The colpotomy cup is fixedly mounted to the second shaft, and stays fixed while the spindle performs the incision by emitting energy and rotating about the axis of the second shaft. 
         [0015]    According to another embodiment, the colpotomy cup is made up of two cups, one inner cup and one outer cup. The inner cup is fixedly mounted to the second shaft and carries the second electrode along its rim, and the outer cup is rotatably mounted to the second shaft and carries the first electrode along all or a part of its rim. Incision is performed while rotating the outer cup about the axis of the second shaft. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    Various exemplary embodiments of the disclosed electrosurgical instrument will be described in detail with reference to the following drawings in which: 
           [0017]      FIG. 1  illustrates a perspective view of a bipolar electrosurgical instrument that incorporates a colpotomy cup, uterine manipulator, and pneumoperitonial sealing device; 
           [0018]      FIG. 2  illustrates a perspective view of the shaft bearing the colpotomy member in an embodiment; 
           [0019]      FIG. 3  illustrates a perspective view of the colpotomy cup in an embodiment; 
           [0020]      FIGS. 4A and 4B  illustrate a perspective view and a plan view of a colpotomy member including the cup and an active electrode that moves relative to the cup; 
           [0021]      FIGS. 5A and 5B  illustrate a perspective view and a top view of a portion of a rim of a colpotomy cup with an undulating (wavy) rim; 
           [0022]      FIG. 6  illustrates a third shaft having a vaginal balloon that functions as a pneumoperitonial sealing device; 
           [0023]      FIG. 7  illustrates a third shaft having a foam plug that functions as a pneumoperitonial sealing device; 
           [0024]      FIG. 8  illustrates a third shaft having a set of malleable discs that function as a pneumoperitonial sealing device; 
           [0025]      FIG. 9  illustrates a first shaft having a manipulator with an enlarged distal portion; 
           [0026]      FIG. 10  illustrates a sagittal view of a patient&#39;s pelvic cavity, having the bipolar electrosurgical device placed in position to perform incision and resection; 
           [0027]      FIG. 11A  illustrates a perspective, exploded view of a colpotomy cup with a rotating outer cup and a fixed inner cup, and  FIG. 11B  illustrates a top, partial view of two rims of a rotating outer cup and a fixed inner cup; and 
           [0028]      FIG. 12  illustrates a perspective, exploded view of a colpotomy cup with a rotating outer cup and a fixed inner cup. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0029]    The following exemplary embodiments are described below with reference to the figures in the context of female pelvic surgery, and in particular total laparoscopic hysterectomy. 
         [0030]      FIG. 1  illustrates a perspective view of a bipolar electrosurgical assembly. The bipolar electrosurgical assembly includes a first (or inner) shaft  10 , a second (or intermediate) shaft  20  and a third (or outer) shaft  30 . The first shaft  10  is a uterine manipulator, with a handle  15  near its proximal end, and an enlarged distal portion  60 . The first shaft  10  typically is rigid or semi-rigid and is used by the surgeon to position the uterus once the distal portion  60  is inserted into the uterus. The second shaft  20  carries the colpotomy cup  50  near its distal end, and a controller  25  near its proximal end. In an exemplary embodiment of the bipolar electrosurgical assembly, the controller  25  is capable of controlling the insertion and retraction of the second shaft  20  in direction  20 B (the longitudinal direction) and rotation  20 A around an axis of the second shaft  20  of the colpotomy cup  50 . The third shaft  30  carries a seal  40  for maintaining pneumoperitoneum. 
         [0031]      FIG. 2  illustrates a perspective view of the second shaft of an exemplary embodiment of a bipolar electrosurgical assembly. The second shaft  20  has at its proximal end the controller  25  to manipulate the rotation and insertion and retraction of the second shaft including the colpotomy cup  50 . In an embodiment according to  FIG. 2 , the first (active) electrode  70  is of a needle-type, and is placed on the distal rim of the colpotomy cup  50 . The needle is electrically conductive, but preferably has an insulative layer over its distal-most end. Thus the cutting energy will be applied from a base portion of the needle electrode  70  located proximal of the distal tip of the needle. Alternatively, the entire needle could be an exposed, electrically conductive member. The cutting signal is supplied to the electrode  70  through an electrically conductive conductor, such as a wire, that is incorporated into the second shaft  20 . The proximal end of the second shaft  20  includes an electrical connection by which the conductor for the electrode  70  is attachable to an energy source. In this embodiment, the second (return) electrode may be annular, disposed around a circumference of the distal rim radially inward from the first electrode  70 , composed of just an arc near the first electrode  70 , or cover all or most of the circumference of the rim. In the  FIG. 2  embodiment, the second electrode  78  extends almost entirely around the rim of cup  50 , and has the first electrode  70  positioned between opposing ends of the second electrode  78 . The second electrode  78  is attached to another electrically conductive conductor, such as a wire, that is incorporated into and extends through the second shaft  20 . The proximal end of the second shaft  20  also includes an electrical connector by which the conductor for the second electrode  78  is attachable to the return line of the energy source. 
         [0032]      FIG. 3  illustrates a perspective view of an embodiment of the colpotomy cup  50  that is provided on the second shaft  20 . This embodiment of the colpotomy cup  50  has a narrower, proximal end  56  with an aperture  58  through which a shaft may pass. In some embodiments, the colpotomy cup  50  will have a hollow internal portion  57  in order to accommodate portions of a shaft, for example. In addition, a rim  55  is located at the distal, open end of the colpotomy cup  50  around the hollow internal portion  57 . 
         [0033]      FIG. 4A  illustrates a perspective view and  FIG. 413  illustrates a plan view of an embodiment of the colpotomy cup  50  that can be provided on the second shaft  20 . This embodiment disposes the first (active) electrode  80  at a distal end of an elongated portion  85  of a spindle  86  protruding from an aperture  58  in the proximal end of the colpotomy cup  50 . This embodiment includes a second electrode  81  which is disposed on the rim  55  of the colpotomy cup  50 . When using this embodiment, the surgeon rotates the spindle  86  while cutting energy is supplied to the first electrode  80  so that the first electrode  80  performs and completes an incision by rotating 360° about the axis of the second shaft. As an alternative to the embodiment shown in  FIGS. 4A and 413 , in which the second (return) electrode  81  is fixed to the cup  50  while the first (active) electrode  80  rotates around the cup  50  with spindle  86 , it is possible to provide both the active and return electrodes on a spindle (like spindle  86 ) that rotates relative to the cup about an axis of the cup. Embodiments that do not require rotation of the cup  50  are advantageous because, due to the cup&#39;s engagement with and support of the uterus, it can be difficult to rotate the cup  50 . 
         [0034]      FIG. 5A  illustrates a perspective view and  FIG. 5B  illustrates a plan view of a portion of a rim  55 A of a colpotomy cup  50 A. In this embodiment of the invention, the cup rim undulates and includes both the active and return electrodes. The colpotomy cup  50 A has a narrower, proximal end  56 A with an aperture  58 A through which the second shaft  20  may pass. Similar to other embodiments, the colpotomy cup  50 A has a hollow internal portion  57 A and a distal rim  55 A around the hollow internal portion  57 A. However, according to an aspect of this embodiment, the rim  55 A of the colpotomy cup  50 A has an undulating surface, which varies in height along the rim  55 A. A first electrode  71  and a second electrode  72  are arranged on the rim  55 A of this embodiment. For example, the first electrode  71  can be on the radially outer edge of the rim  55 A and the second electrode  72  can be on the radially inner edge of the rim  55 A. A technique for using this embodiment includes advancing the colpotomy cup  50 A longitudinally while applying a voltage differential between the first electrode  71  and the second electrode  72 . When tissue makes contact with the first electrode  71 , cutting energy is focused at the parts of the colpotomy cup  50 A which are in contact with the tissue at that moment. As the colpotomy cup  50 A is advanced longitudinally, first the highest part(s) of the rim  55 A contact and cut tissue. As the colpotomy cup  55 A is advanced further, the lower part(s) of the rim  55 A contact and cut tissue. 
         [0035]      FIGS. 6-8  illustrate different seals for maintaining pneumoperitoneum that may be located on the third shaft  30  in different embodiments of the invention.  FIG. 6  illustrates an embodiment of the invention where the third shaft  30  includes a vaginal balloon  41  as the seal. An aspect of this embodiment of the seal is that the vaginal balloon can be in either a deflated state  41 A or a fully inflated state  41 , depending on the configuration that the physician desires. In another aspect of this embodiment, the third shaft  30  is slidably mounted over the second shaft and is capable of being positioned prior to inflation of the vaginal balloon  41 . The third shaft includes a gas passage via which the balloon  41  can be inflated and deflated. 
         [0036]      FIG. 7  illustrates an embodiment of the invention where the third shaft  30  includes a foam plug  42  as the seal. In an aspect of this embodiment, the third shaft  30  is slidably mounted over the second shaft and is capable of being positioned during surgery. The foam plug can be made of, for example, closed cell foam to form a soft malleable plug that is gas impermeable or an open cell foam with an external skin again making it gas impermeable. An important characteristic of the foam plug is to readily deflect for insertion without tissue injury and easy placement while subsequently conforming to the internal surface contours of the vaginal canal, in a manner so as to create the desired gas sealing or prevent the gas from leaking. 
         [0037]      FIG. 8  illustrates an embodiment of the invention where the third shaft  30  includes malleable discs  43 . The figure is illustrative and exhibits a configuration including three discs,  43 A,  43 B, and  43 C. In an aspect of this embodiment, the malleable discs are configured so that the smallest disc,  43 A, is the most distal. The discs increase in size in the proximal direction, with the most proximal,  43 C, being the largest. The number, position, and size of the discs may be varied as required for a particular patient or application. The discs  43  are made of, for example, a soft malleable polymeric material or composite of materials such as LDPE or silicone that is gas impermeable. The malleability is critical for ease of insertion into the vaginal canal as well as limiting any tissue damage upon insertion and during placement. 
         [0038]      FIG. 9  illustrates an embodiment of the first shaft  10 . In an aspect of this embodiment, a handle  15  for controlling the movement and orientation of the first shaft  10  is included near its proximal end. Also in this embodiment, an enlarged distal portion  60  is located near the distal end of the first shaft  10 . The enlarged distal portion  60  of this embodiment may pass through the cervix, and enter the uterus for positioning of the uterus. 
         [0039]      FIG. 10  illustrates a sagittal view of a patient&#39;s pelvic cavity with an embodiment of the bipolar electrosurgical device in position to perform a TLH procedure. In this illustration, V represents the ventral side of the patient, and D represents the dorsal side of the patient. The enlarged distal portion  60  of the first shaft is located within the patient&#39;s uterus  210 . The second shaft  20  has been inserted so that the colpotomy cup  50  is located at the cervico-vaginal junction  200 . The third shaft  30  has a vaginal balloon  41  as a seal. The third shaft  30  has been inserted over and along the second shaft  20  such that the vaginal balloon  41  is located within the vaginal canal  220  and inflated so that it is making contact with the vaginal canal  220  and maintaining pneumoperitoneum during the laparoscopic procedure. The first electrode  70  is of a needle type, which is located on the rim of the colpotomy cup  50 . In the illustrated embodiment, the second electrode (not visible) is located along the rim of the colpotomy cup  50 , but not in direct contact with the first electrode  70 . 
         [0040]    In the embodiment illustrated in  FIG. 10 , the second shaft  20  is slidably and rotatably movable over the first shaft  10 . The third shaft  30  is slidably and rotatably movable over the second shaft  20 . In the embodiment illustrated in  FIG. 11 , rotation of the second shaft  20  controls rotation of the colpotomy cup  50 . By this mechanism, an incision is formed along the cervico-vaginal junction  200  by the first electrode  70  as it rotates about the axis of the second shaft  20 . 
         [0041]      FIGS. 11A and 11B  illustrate an embodiment of a colpotomy cup with a fixed inner cup  59 B and a rotatable outer cup  5013 . Fixed inner cup  5913  has an aperture  58 B at its proximal end, and rotatable outer cup  50 B has an aperture  58 C at its proximal end. In this embodiment, the fixed inner cup  5913  is fixedly attached to the second shaft  20 . The rotatable outer cup  50 B is rotatably attached to the second shaft  20 . The first electrode  76  can be placed along the rim  5513  of the rotatable outer cup  50 B, and the second electrode  75  can be placed along the rim  51 B of the fixed inner cup  59 B. This embodiment performs the incision by rotating the rotatable outer cup  50 B, while leaving the fixed inner cup  59 B in a fixed position, while emitting energy from the first electrode  76  along the rim  55 B of the rotatable outer cup  50 B. 
         [0042]      FIG. 12  illustrates an embodiment of a colpotomy cup with a fixed inner cup  59 C and a rotatable outer cup  50 C. Fixed inner cup  59 C has an aperture  58 D at its proximal end, and rotatable outer cup  50 C has an aperture  58 F at its proximal end. In this embodiment, the fixed inner cup  59 C is fixedly attached to the second shaft  20 . The rotatable outer cup  50 C is rotatably attached to the second shaft  20 . The first electrode can take one of two forms. In the first form, the first electrode can be a portion  7613  of the rim  55 C of the rotatable outer cup  50 C. Alternatively, the first electrode can be a needle electrode  76 C placed on the rim  55 C of the rotatable outer cup  50 C. The second electrode  75  can be placed along the rim  51 C of the fixed inner cup  59 C. This embodiment performs the incision by rotating the rotatable outer cup  50 C, while leaving the fixed inner up  59 C in a fixed position, while emitting energy from the first electrode  76 B or  76 C placed along the rim  55 C of the rotatable outer cup  50 C. 
         [0043]    The illustrated exemplary embodiments are intended to be illustrative and not limiting. Various changes may be made without departing from the spirit and scope of the invention. For example, a light can be included at the location of the electrodes to improve visibility during cutting. This would provide added safety to the user in ensuring that the electrode(s) is(are) positioned properly before cutting.