Patent Document

BACKGROUND 
     This disclosure relates to systems for removing tissue from patients, and is particularly useful for removing pedunculated tissue structures such as polyps and pedunculated uterine fibroids. 
     Uterine fibroids are the most common pelvic tumor in women, affecting approximately one quarter of women during their reproductive years. Uterine fibroids are generally noncancerous, but may potentially lead to infertility or cause adverse effects if they occur during pregnancy. Typical symptoms include abnormal bleeding, pressure, or pain. 
     Uterine fibroids are categorized based on location on the uterus. Sub-mucosal fibroids form on the inside wall of the uterus; sub-serosal fibroids form on the outside wall of the uterus; intra-mural fibroids form within the wall of the uterus; and pedunculated fibroids are connected to the inside or outside wall of the uterus by a stalk. 
     Current uterine fibroid treatments include both pharmaceutical and surgical techniques. Pharmaceutical treatments often do not adequately treat the symptoms of uterine fibroids, ultimately necessitating surgical intervention. Surgical techniques include hysterectomy, myomectomy, endometrial ablation, myolysis and uterine artery occlusion. In addition, interventional radiology and high frequency focused ultrasound techniques exist for the treatment of uterine fibroids. 
     All of these treatment techniques suffer from shortcomings, such as the risk of relapse, infertility, and applicability to only one or a few types of uterine fibroids. 
     SUMMARY 
     The disclosed electrosurgical device, which is suited for removing pedunculated tissue structures such as, for example, polyps and certain fibroids, includes bipolar surface electrodes and a bipolar snare. In preferred embodiments, the device includes a probe having a proximal end and a distal end, bipolar surface electrodes adjacent to the distal end of the probe, and a bipolar snare extending distally from the distal end of the probe and including first and second snare electrodes. The bipolar surface electrodes are separated from each other by a gap and extend over a portion of the distal end of the probe. 
     Providing both a bipolar snare and bipolar surface electrodes advantageously reduces thermal spread from occurring (compared to the use of a monopolar snare) when using the snare to excise the pedunculated tissue structure. The bipolar surface electrodes can be used to coagulate the point of excision. Thus, the device is effective at minimizing bleeding. Further, by providing the snare and the coagulating surface electrodes on the same device, the procedure time is shortened. 
     The bipolar snare preferably includes an electrically insulative member disposed between distal ends of the first and second snare electrodes. In addition, an insulative material preferably is disposed between the bipolar surface electrodes. 
     The bipolar snare also includes a handpiece coupled to a proximal end of at least one of the snare electrodes. The handpiece can be manipulated by a user to tighten the bipolar snare around a part of a stem of a pedunculated tissue structure to be removed. 
     According to preferred embodiments, the bipolar surface electrodes include a first surface electrode and a second surface electrode separated from the first surface electrode by a gap. As noted above, the gap can include an insulative material to prevent short-circuiting from occurring between the first and second surface electrodes. Accordingly, when supplied with an appropriate signal, current will flow from the first surface electrode, through adjacent tissue, to the second surface electrode so as to coagulate the point of tissue excision. The first and second surface electrodes can be strips of electrically conductive material arranged so as to alternate with each other over the distal end of the probe. According to one embodiment, the first and second surface electrodes are formed into a double helix around the distal end of the probe. 
     The electrosurgical device also preferably includes first and second terminals by which the device is coupled to a bipolar energy source. In addition, the device includes circuitry coupling the first and second terminals to the bipolar surface electrodes and to the first and second snare electrodes. Such circuitry is used to control the supply of bipolar energy to the surface electrodes and to the snare electrodes. In preferred embodiments, the circuitry couples the first and second terminals to proximal ends of the bipolar surface electrodes and to proximal ends of the first and second snare electrodes. 
     According to some embodiments, the circuitry selectively causes one or the other of the snare electrodes and the surface electrodes to become “active.” In such embodiments, the circuitry includes a switching device by which the first and second terminals are selectively coupled to either (i) the proximal ends of the bipolar surface electrodes, or (ii) the proximal ends of the first and second snare electrodes. According to some embodiments, the switching device includes (a) a first relay that selectively couples the first terminal to the proximal end of either a first one of the bipolar surface electrodes or the first snare electrode, and (b) a second relay that selectively couples the second terminal to the proximal end of either a second one of the bipolar surface electrodes or the second snare electrode. 
     According to one example, when in a first state, the first relay couples the first terminal to the proximal end of the first one of the bipolar surface electrodes while the second relay couples the second terminal to the proximal end of the second one of the bipolar surface electrodes. In addition, when in a second state, the first relay couples the first terminal to the proximal end of the first snare electrode while the second relay couples the second terminal to the proximal end of the second snare electrode. 
     According to another example, the first terminal is coupled to both the proximal end of a first one of the bipolar surface electrodes and to the proximal end of the first snare electrode, and the switching device includes a relay that selectively couples the second terminal to the proximal end of either a second one of the bipolar surface electrodes or the second snare electrode. For example, when in a first state, the relay couples the second terminal to the proximal end of the second bipolar surface electrode, and when in a second state, the relay couples the second terminal to the proximal end of the second snare electrode. 
     According to other embodiments, the circuitry can cause both the snare electrodes and the surface electrodes to be “active” at the same time. In such embodiments, the circuitry simultaneously couples (a) the first terminal to the proximal end of a first one of the bipolar surface electrodes and to the proximal end of the first snare electrode, and (b) the second terminal to the proximal end of a second one of the bipolar surface electrodes and to the proximal end of the second snare electrode. Accordingly, the bipolar surface electrodes and the bipolar snare electrodes can be concurrently supplied with power so that coagulation can be promoted as the pedunculated tissue structure is excised by the snare electrodes. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiments will be described in detail with reference to the following drawings in which: 
         FIG. 1  illustrates various locations of uterine fibroids; 
         FIG. 2  is a side view of an electrosurgical device (a pedunculated tissue structure removal device) according to one embodiment of the invention; 
         FIG. 3  is a diagram of circuitry that includes a first switching device by which the snare electrodes and the surface electrodes are selectively activated; 
         FIG. 4  is a diagram of circuitry that includes a second switching device by which the snare electrodes and the surface electrodes are selectively activated; and 
         FIG. 5  is a diagram of circuitry by which the snare electrodes and the surface electrodes are concurrently activated. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The following exemplary embodiments are described below with reference to the figures in the context of uterine fibroid treatment, and in particular removal of pedunculated uterine fibroids. However, the disclosed electrosurgical device is not limited to use for removing pedunculated fibroids. The device is suitable for removing various pedunculated tissue structures such as, for example, polyps located, for example, in the gastro-intestinal tract. Thus, although the following description is primarily focused on the removal of pedunculated uterine fibroids, other pedunculated tissue structures can be removed with the disclosed device. 
       FIG. 1  illustrates different anatomical locations of uterine fibroids that can potentially afflict a patient. A sub-mucosal fibroid  40  is located on the inside wall of the uterus  10 . A sub-serosal fibroid  20  is located on the outside wall of the uterus  10 . An intra-mural fibroid  50  is located within the wall  14  of the uterus  10 . A pedunculated fibroid  30  is attached to the outer wall of the uterus  10 . Because it is attached to the outer wall of the uterus  10 , fibroid  30  more specifically is known as a pedunculated sub-serosal fibroid. Fibroid  34  is known as a pedunculated sub-mucosal fibroid because it is attached to the inner wall of the uterus  10 . 
     The location of a patient&#39;s fibroid(s) is first determined by one or more known imaging techniques. For example, ultrasonic imaging (known as “ultrasound”) can be performed using a transducer placed externally of the patient&#39;s body or located within the uterus, for example, at the end of a transcervically inserted ultrasonic probe. MRI also could be used. Such technologies also can be used to locate polyps. 
     Once the location of the (or each) fibroid has been determined, the surgeon will determine how to access the fibroid(s). For example, pedunculated sub-mucosal fibroids typically are accessed transcervically, whereas pedunculated sub-serosal fibroids typically are accessed from the pelvic cavity (i.e., laproscopically accessed). However, the manner of accessing each fibroid also depends on the desired outcome of the surgery (e.g., fertility, resolution of the patient&#39;s symptoms, etc.), the size of each fibroid, as well as the location of other fibroids within the uterus. 
     Once the electrosurgical device has been inserted into the patient, the patient&#39;s uterus is manipulated into position to present the fibroid for treatment. The snare of the device then is looped around the fibroid and tightened to occlude the stalk of the pedunculated fibroid. The snare then is electrically activated to excise the fibroid. Bleeding at the point of excision is minimized by coagulation achieved with the bipolar surface electrodes provided at the distal end of the device. As will be described below, the surface electrodes can be activated concurrently with activation of the snare electrodes or after the snare electrodes have been activated. The excised fibroid then is extracted from the patient. 
     An electrosurgical device (pedunculated tissue structure removal device)  100  according to one embodiment of the invention is shown in  FIG. 2 . The device  100  includes a probe (or probe body)  130  having a distal end  132 , for insertion into the patient, and a proximal end  134  having a handle section  136  that is grasped by the surgeon. A bipolar snare  110  extends from apertures  152  in the distal end  132  of the probe  130 . In addition, bipolar surface electrodes  120  are provided adjacent to the distal end  132  of the probe  130 . 
     The bipolar snare  110  includes a first snare electrode  112  and a second snare electrode  114 . Distal ends the first and second snare electrodes  112 ,  114  are attached to each other by an electrically insulative member  116  so that current does not flow between the distal ends of the electrodes  112 ,  114 . Rather, when looped and tightened around the stalk of a pedunculated fibroid, and activated, current will flow from electrode  112  through the stalk and to electrode  114 . The supplied current will be sufficient to cut through the stalk and detach the fibroid, which then can be removed by a grasper device such as forceps. A proximal end of at least one of the electrodes  112 ,  114  is attached to a pulling member  140  that can be moved by the surgeon so as to open or close the snare  110 .  FIG. 2  shows the snare in the open position. Once the snare has been located around the stalk of a pedunculated fibroid (or polyp), the surgeon moves the pulling member  140  proximally so as to tighten the snare  110  around the fibroid (or polyp) stalk. 
     Snares having pulling members are known, for example, from U.S. Pat. No. 4,493,320, U.S. Pat. No. 4,905,691 and U.S. Pat. No. 6,610,056, the disclosures of which are incorporated herein by reference in their entireties. Of these patents, U.S. Pat. No. 4,493,320 and U.S. Pat. No. 4,905,691 show bipolar snares, whereas U.S. Pat. No. 6,610,056 shows a monopolar snare. 
     The bipolar surface electrodes  120  include at least two different electrodes that are electrically isolated from each other. In the  FIG. 2  embodiment, the bipolar surface electrodes include a first electrode  122  and a second electrode  124 . An electrically insulative material  126  is provided in a gap between the first and second surface electrodes  122 ,  124 . Accordingly, when supplied with an appropriate signal, current will flow from the first surface electrode  122 , through adjacent tissue that contacts the first and second surface electrodes  122 ,  124 , and then flow into the second surface electrode  124  so as to coagulate the point of fibroid (or polyp) excision. Although not shown in  FIG. 2 , proximal ends of the surface electrodes  122 ,  124  are attached to electrical conductors that extend through the probe  130  to contacts provided in an electrical connector  160  disposed near the proximal end  134  of the probe  130 . 
     In the  FIG. 2  embodiment, the first and second surface electrodes  122 ,  124  each are strips of electrically conductive material. In the  FIG. 2  embodiment, the surface electrodes  122  and  124 , spaced from each other, are spirally wound around a portion of the distal end  132  of the probe  130  to form a double helix. However, the surface electrodes can be arranged in ways other than a double helix. For example, the electrodes could extend longitudinally along the longitudinal axis of the distal portion  132  of the probe  130 . As another alternative, the electrodes could be conductive pads that cover adjacent areas of the distal portion  132  of probe  130 . See, for example, the aforementioned U.S. Pat. No. 6,610,056 and U.S. Pat. No. 4,532,924, the disclosures of which are incorporated herein by reference in their entireties. 
     As shown in  FIGS. 3-5 , a bipolar energy source  300  is provided and supplies energy to the snare and surface electrodes  112 ,  114 ,  122 ,  124  via circuitry  200   a ,  200   b  or  200   c . According to the embodiments shown in  FIGS. 3 and 4 , energy is selectively supplied to either the snare electrodes or to the surface electrodes such that cutting by the snare electrodes occurs prior to coagulation by the surface electrodes. In the embodiment shown in  FIG. 5 , energy is simultaneously supplied to both the snare electrodes and to the surface electrodes such that cutting by the snare electrodes occurs concurrently with coagulation by the surface electrodes. The  FIG. 5  embodiment thus is very effective at minimizing bleeding and reducing procedure time. 
     As shown in  FIGS. 3-5 , the alternating outputs of the bipolar energy source  300  (also referred to as the positive and negative outputs) are coupled to first terminal  302  and second terminal  304  respectively. As noted above, circuitry ( 200   a ,  200   b  or  200   c ) couples the first and second terminals  302 ,  304  to the bipolar surface electrodes  122 ,  124  and to the first and second snare electrodes  112 ,  114 . Such circuitry is used to control the supply of bipolar energy to the surface electrodes and to the snare electrodes. The circuitry couples the first and second terminals  302 ,  304  to conductors associated with proximal ends of the bipolar surface electrodes and of the first and second snare electrodes; however, for purposes of simplicity of explanation, the conductors also are considered to be part of the proximal ends of the electrodes. Thus, snare electrode  112  has proximal end  112   a , snare electrode  114  has proximal end  114   a , surface electrode  122  has proximal end  122   a , and surface electrode  124  has proximal end  124   a.    
     According to the embodiments shown in  FIGS. 3 and 4 , the circuitry ( 200   a  or  200   b ) selectively causes either the snare electrodes  112 ,  114  or the surface electrodes  122 ,  124  to become “active.” In such embodiments, the circuitry includes a switching device ( 250  or  260 ) by which the first and second terminals  302 ,  304  are selectively coupled to either (i) the proximal ends  122   a ,  124   a  of the bipolar surface electrodes  122 ,  124 , or (ii) the proximal ends  112   a ,  114   a  of the first and second snare electrodes  112 ,  114 . According to the  FIG. 3  embodiment, the switching device  250  includes (a) a first relay  252  that selectively couples the first terminal  302  to either the proximal end  122   a  of the bipolar surface electrode  122  or to the proximal end  114   a  of the snare electrode  114 , and (b) a second relay  254  that selectively couples the second terminal  304  to either the proximal end  124   a  of the bipolar surface electrode  124  or to the proximal end  112   a  of the snare electrode  112 . 
     According to the  FIG. 3  embodiment, when in a first state, the first relay  252  couples the first terminal  302  to the proximal end  114   a  of a first one of the snare electrodes  114  while the second relay  254  couples the second terminal  304  to the proximal end  112   a  of a second one of the snare electrodes  112 . In addition, when in a second state, the first relay  252  couples the first terminal  302  to the proximal end  122   a  of a first one of the bipolar surface electrodes  122  while the second relay  254  couples the second terminal  304  to the proximal end  124   a  of a second one of the bipolar surface electrodes  124 . The two relays  252  and  254  also can be considered to be a two pole relay. 
     According to the  FIG. 4  embodiment, the first terminal  302  is coupled to both the proximal end  122   a  of a first one of the bipolar surface electrodes  122  and to the proximal end  114   a  of the first snare electrode  114 , and the switching device includes a relay  260  that selectively couples the second terminal  304  to either the proximal end  124   a  of a second one of the bipolar surface electrodes  124  or to the proximal end  112   a  of the second snare electrode  112 . In the  FIG. 4  embodiment, when in a first state, the relay  260  couples the second terminal  304  to the proximal end  112   a  of the second snare electrode  112 , and when in a second state, the relay  260  couples the second terminal  304  to the proximal end  124   a  of the second bipolar surface electrode  124 . 
     According to the  FIG. 5  embodiment, circuitry  200   c  causes both the snare electrodes  112 ,  114  and the surface electrodes  122 ,  124  to be “active” at the same time. In particular, the circuitry  200   c  simultaneously couples (a) the first terminal  302  to the proximal end  122   a  of a first one of the bipolar surface electrodes  122  and to the proximal end  114   a  of the first snare electrode  114 , and (b) the second terminal  304  to the proximal end  124   a  of a second one of the bipolar surface electrodes  124  and to the proximal end  112   a  of the second snare electrode  112 . Accordingly, the bipolar surface electrodes  122 ,  124  and the bipolar snare electrodes  112 ,  114  are concurrently supplied with power so that coagulation can be promoted as the fibroid (or polyp) is excised by the snare electrodes. This further reduces bleeding and shortens the overall procedure. The energy source  300  is simply switched on or off to control the supply of power to all of the electrodes  112 ,  114 ,  122 ,  124 . 
     The electrical circuits are shown schematically in  FIGS. 3-5 , and can be implemented many different ways, and also may vary depending on the type of generator to which the device is connected. For example, if the generator has multiple output lines for (bipolar) coagulation and cut, the electrosurgical device could be connected to more than one of the lines (for example, a first line or port that provides bipolar coagulation energy and a second line or port that provides bipolar cutting energy), and the switching could be performed depending on which of the ports was selected to be activated by the user. In such an implementation, the user could, for example, select between different switches or buttons provided on the generator. Alternatively, switches could be provided on the device itself (e.g., on the handpiece of the device) in order to switch between which electrodes (snare electrodes and/or surface electrodes) are to receive energy, and then the energy would be supplied when an activation button/switch is pressed. Furthermore, a capacitance could be included in the circuitry such that different levels of energy are provided to the snare electrodes versus the surface electrodes based on a single output of the generator such that the snare electrodes are supplied with an appropriate cutting energy, whereas the surface electrodes are supplied with an appropriate coagulation energy. 
     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.

Technology Category: 1