Abstract:
A device for degenerating a fibroid comprises a gripper mechanism sized and shaped so as to grip a uterine artery and a rotating mechanism attached to the gripper mechanism. The rotating mechanism may be rotated so as to rotate said gripper mechanism, thereby twisting a gripped uterine artery so as to obstruct blood flow through the artery. In a method of degenerating a uterine fibroid, the aforesaid gripping device is used to catch hold of a uterine artery and is rotated in a direction so as to twist the uterine artery about itself, thereby obstructing blood flow to the uterine fibroid. The gripping device is held in place for a period of time needed to degenerate the fibroid.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates, generally, to the use of mechanical instruments to block the flow of blood through the arteries. More specifically, it relates to the treatment of uterine fibroids by obstruction of the uterine arteries. 
       BACKGROUND OF THE INVENTION 
       [0002]    Uterine leiomyomas (i.e., fibroids) are extremely common benign tumors, which are located primarily within the uterine muscle (i.e., intramural fibroids), the uterine cavity (i.e., submucosal fibroids) or on the serosal surface of the uterus. Such fibroids occur in approximately 20% to 30% of women older than 30 years of age. Medical treatment is usually sought when the fibroids are associated with menorrhagia, pelvic pain or urinary symptoms, or when they are suspected to be the cause of infertility. Treatment options include medical therapy and various types of surgical intervention. 
         [0003]    Hysterectomy is considered to be the definitive surgical treatment for those women who no longer wish to maintain their fertility. Though effective, this method has a number of undesirable characteristics. First is the mortality rate for this procedure, which is approximately 30 times as great as the mortality rate for women who have not had hysterectomies. Further adverse effects of hysterectomies include damage to adjacent organs, including removal of the ovaries, lengthy hospital stays and periods of recovery, and an increased likelihood of cardiac arrest, decreased sexual pleasure, and increases in depression or anxiety. Surgical removal of fibroids without hysterectomy, by any surgical method, presents a risk of recurrence of fibroids or, more often, failure to observe existing fibroids or misidentification of the fibroids that are causing adverse symptoms. 
         [0004]    It has been established that fibroids can be treated by non-surgical therapies involving the temporary obstruction of the blood flow within the arteries transporting blood into the uterus. One example of such a treatment is uterine artery embolization (UAE). UAE involves the injection of tiny particles of polyvinyl alcohol (PVA) through blood vessels to block the arteries supplying blood to the fibroids. This blockage of the blood supply causes degeneration of the fibroids leading to their death. However, UAE is performed by radiologists who, typically, are unfamiliar with practices of gynecological care. As of now, UAE&#39;s are performed in radiology suites, which have high installation and operational costs and which, therefore, are generally restricted to major medical centers. Also, however UAE is practiced, the movement of the PVA particles is flow-directed and their distribution is not limited to the arteries that supply the fibroids, but may affect blood flow to other areas of the uterine tissue or to the ovaries. 
         [0005]    There exists a need for devices and methods that can be used to temporarily obstruct the flow of blood to fibroids. The devices should be relatively inexpensive and simple to apply, and should allow the physician to control the degree by which blood flow is reduced. Various devices and methods for obstructing the uterine arteries have been disclosed in the prior art: 
         [0006]    U.S. Pat. No. 6,254,601 discloses methods for penetrating the wall of the vaginal vault near the uterine artery with devices that sense the locations of the anatomical structures and occlude the uterine artery. A number of methods and devices are disclosed. These disclosures are also presented in U.S. Pat. Nos. 6,602,251 and 6,764,488. 
         [0007]    U.S. Pat. No. 6,550,482 discloses a clamp for temporarily obstructing the uterine artery. The clamp stretches the wall of the vaginal vault around the artery and applies pressure to stop blood flow. 
         [0008]    U.S. Patent Publication No. 2002/0165579 discloses a compression device for distending the wall of the vaginal vault and thus compressing the uterine artery. Doppler ultrasound techniques are used to locate the uterine artery and sense when blood flow has stopped. 
         [0009]    U.S. Patent Publication No. 2002/0183771 discloses a compression device that clamps around the uterine artery and the vaginal wall to stop blood flow. 
         [0010]    U.S. Patent Publication No. 2002/0188306 discloses a forceps-type clamp that is inserted into the vagina and clamps around the uterine artery and the vaginal wall. Ultrasound sensors are placed on the ends of the clamp to allow location of the uterine artery and sense blood flow. Similar forceps-type clamps are described in a number of other references. 
         [0011]    U.S. Patent Publication No. 2002/0124853 is directed to a method of temporarily obstructing blood flow through the uterine artery for a set period of time, then re-establishing blood flow through the artery. A forceps-type clamp is used to compress the artery from both sides. 
         [0012]    U.S. Patent Publication No. 2004/0092979 discloses a device with paddles that are used to distend the wall of the vaginal vault around the uterus, thus compressing both uterine arteries at the same time. 
         [0013]    U.S. Patent Publication No. 2003/0120286 discloses a clip for encircling and compressing a body lumen, of which a uterine artery is one example. 
         [0014]    U.S. Patent Publication No. 2004/0097962 discloses constriction devices that can be deployed to distend the vaginal wall around the uterus and thus obstruct the uterine arteries. 
       SUMMARY OF THE INVENTION 
       [0015]    The invention, in general, relates to a device and a method for degenerating a fibroid by obstructing the flow of blood through a uterine artery. In general, the device includes a gripper mechanism adapted to grip a uterine artery and a rotating mechanism for rotating the gripper mechanism. In a first embodiment, the gripper mechanism includes a hook and the rotating mechanism includes a shaft continuous with the hook. In a second embodiment, the gripper mechanism includes a pair of prongs within a sheath. The prongs act jointly to push a portion of the wall of the vaginal vault of a female patient around a uterine artery, thereby gripping both the portion off the wall and the artery. When used for degenerating a fibroid, each of the embodiments twists the uterine artery about itself so as to obstruct blood flow through the fibroid for a time sufficient to degrade the fibroid. 
         [0016]    It should be understood that the embodiments described above are merely exemplary and that additional embodiments may be realized that are within the scope of the invention. The invention is further described in the Detailed Description of the invention presented below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    For a more complete understanding of the present invention, reference is made to the following detailed description of the present invention considered in conjunction with the accompanying drawings, in which: 
           [0018]      FIG. 1  is a perspective illustration of a hook-shaped device for twisting a uterine artery according to an embodiment of the invention. 
           [0019]      FIG. 2  is an illustration of the device of  FIG. 1  positioned to capture a uterine artery. 
           [0020]      FIG. 3  illustrates the device of  FIG. 1  in position after having twisted a uterine artery, the device being shown in combination with an optional pessary. 
           [0021]      FIG. 4  illustrates a two-pronged device in an extended position for twisting a uterine artery according to another embodiment of the invention. 
           [0022]      FIG. 5  illustrates the device of  FIG. 4  in a retracted position, a portion being broken away to facilitate consideration and discussion. 
           [0023]      FIG. 6  illustrates the device of  FIG. 4  in an extended position to capture a uterine artery. 
           [0024]      FIG. 7  illustrates the device of  FIG. 4  in a retracted position after capturing a uterine artery. 
           [0025]      FIG. 8  illustrates the device of  FIG. 4  in position after having twisted a uterine artery, the device being shown in combination with an optional pessary. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0026]    With reference to  FIG. 1 , a hook-shaped device  10  for catching hold and twisting a uterine artery comprises a shaft  12  having a hook  14  at one end of the shaft  12  and a handle  16  at the other end. The tip  18  of the hook  14  is bent away from the body of the hook  14 , reducing the likelihood that the tip  18  will become snagged on any tissue ensnared by the hook  14 . The shaft  12 , hook  14 , handle  16  and tip  18  may be manufactured as a single piece. The shaft  12  and/or handle  16  may be roughened to increase friction at the surface of the device  10  and make it easier to grip. The device  10  may be made of a biologically inert metal, a rigid plastic, or other rigid material. If any portion of the device  10  is to remain inside the body after use, it may be made of a biodegradable polymer. The bioabsorbable polymers that can be used to make devices according to the present invention include conventional biocompatible, bioabsorbable polymers including polymers selected from the group consisting of aliphatic polyesters, poly(amino acids), copoly(ether-esters), polyalkylene oxalates, polyalkylene diglycolates, polyamides, tyrosine derived polycarbonates, poly(iminocarbonates), polyorthoesters, polyoxaesters, polyamidoesters, polyoxaesters containing amine groups, poly(anhydrides), polyphosphazenes, poly(propylene fumarates),. absorbable poly(ester urethanes), biomolecules (i.e., biopolymers such as collagen, elastin, bioabsorbable starches,. etc.) and combinations and blends thereof. The polyoxaesters include the polymers based on 3,6-dioxaoctanedioic acid, 3,6,9-trioxaundecanedioic acid, and the diacid known as polyglycol diacid, which can be made from the oxidation of low molecular weight polyethylene glycol. Currently, aliphatic polyesters are among the preferred absorbable polymers for use in ranking the implants according to the present invention. Aliphatic polyesters can be homopolymers, copolymers (random, block, segmented, tapered blocks, graft, triblock, etc.) having a linear, branched or star structure. Suitable monomers for making aliphatic homopolymers and copolymers may be selected from the group consisting of, but are not limited, to lactic acid (both L- and D-isomers), lactide (including L-, D-, and meso-lactide), glycolic acid, glycolide, ε-caprolactone, p-dioxanone (1,4-dioxan-2-one), trimethylene carbonate (1,3-dioxan-2-one), and combinations thereof. Aliphatic polyesters can be hornopolymers, copolymers (random, block, segmented, tapered blocks, graft, triblock, etc.) having a linear, branched or star structure; alternately they can be a component of a cross-linked network. It is to be understood that exemplary bioabsorbable, biocompatible polymers may be generally synthesized by a ring-opening polymerization of the corresponding lactone monomers or by polycondensation of the corresponding hydroxy-acids, or by combinations of these two polymerization methodologies. Thus as used herein, the term “polyglycolide” is understood to include polyglycolic acid. Further, the term “polylactide” is understood to include polymers of L-lactide, D-lactide, meso-lactide, blends thereof, and lactic acid polymers had copolymers in which other moieties are present in amounts less than 50 mole percent. Other aliphatic polyesters that may provide utility include the hydroxybutyrates and polyhydroxyvalerates. 
         [0027]    Application of the device  10  is illustrated in  FIGS. 2 and 3 . Referring to  FIG. 2 , the portions of the female anatomy pertinent to the application of the hook-shaped device  10 , and of devices discussed hereinafter, include the wall  20  of the-vaginal vault  22 , the uterine arteries  24 ,  24 ′ and the cervix  26 . 
         [0028]    First, an incision (not shown) is made in the wall  20  of the vaginal vault  22  to expose the uterine artery  24  and the artery  24  is dissected. The hook  14  is inserted through the incision and positioned over the uterine artery  24  so as to ensnare it. The hook  14  may be put into position using a forceps (not shown) or other device capable of releasably gripping the device  10 . 
         [0029]    Turning to  FIG. 3 , in a preferred embodiment, the shaft  12  passes through the body of an optional pessary  32  which surrounds the cervix  26 . The pessary  32  allows the shaft  12  to be moved along the longitudinal axis of the shaft  12 , but may provide some resistance to its rotational movement. The hook-shaped device  10  may be provided separately from the pessary  32 , and inserted therethrough, or they may be provided together in a single device. The hook-shaped device  10  is then rotated so that the hook  14  twists the uterine artery  24  about itself so as to completely block blood flow. The shaft  12  is prevented from rotating back towards its original position through a friction fit within the body of the pessary  32 , or by a catch (not shown) inside of the pessary  32 . Suitable catches include one or two-sided clamps, clips or other grasping devices. 
         [0030]    The hook-shaped device  10  is held in position for the length of time needed to degenerate or kill the fibroid without killing adjacent tissues. Preferably, blood flow through the uterine artery  24  is blocked for about 6 to 8 hours, after which time the device  10  is counter-rotated so as to untwist the artery, allowing blood flow to resume. The uterine artery  24  can then be freed from the hook  14  by lifting the hook  14  away from the artery. The device  10  may be shaken gently, if necessary, to free the uterine artery  24  from the hook  14 . When the uterine artery  24  has been freed from the hook  14 , the hook  14  may be retracted through the incision and removed from the vaginal vault  22 . 
         [0031]    During the procedure, it is important that the position of the hook-shaped device  10  is known relative to the uterine artery  24 , so that the device is not mistakenly applied to another blood vessel or to the ureter (not shown). The position of the hook-shaped device  10  relative to the uterine artery  24  may be determined by any of a number of imaging techniques and/or techniques for monitoring the flow of blood through blood vessels. 
         [0032]    Appropriate sensors for imaging and/or blood flow detection include blood flow sensors, sound sensors, pressure sensors, or electromagnetic radiation sensors (e.g., X-ray detectors). Sensors may be mounted on the hook-shaped device  10 , on the forceps or other tool used to place or remove the hook-shaped device  10 , or on implements temporarily attached to the hook-shaped device during insertion. Since any sensor that is used will have associated wiring it is preferable to use an implement that can be removed after the hook-shaped device  10  is applied to the uterine artery  24 . In the absence of such an implement, the patient may be able to move about comfortably with the hook-shaped device  10  in place. 
         [0033]    Techniques that may be used include direct visual examination, abdominal ultrasound, Doppler ultrasound, X-ray detection, sound detection, and angiography. Direct visual examination is the preferred method. Ultrasound techniques are also of value because they are reliable, real-time techniques for imaging the position of the hook-shaped device  10  in relation to the uterine artery  24  while the procedure is underway. Doppler ultrasound techniques provide the additional ability to determine when blood flow ceases or is restored. Optical fibers may also be used to illuminate the organs, and transmit images to an optical viewer. Adaptations of suitable techniques for use with the hook-shaped device  10 , or other devices that may be discussed herein, will be apparent to a person skilled in the application of such techniques to surgical procedures. 
         [0034]    Turning to  FIGS. 4 and 5 , a two-pronged device  34  comprises a shaft  36  (see  FIG. 5 ), which is bifurcated into a prong  38 , having a free end  40  and a bent portion  42  adjacent the free end  40 , and a prong  44 , also having a free end  46  and a bent portion  48  adjacent the free end  46 . Each of the bent portions  42 ,  48  has a concave (i.e., open) side, the concave sides being oriented such that they face each other. The shaft  36  and prongs  38 ,  44  may be formed as a single piece or as two or more pieces secured to each other. The free ends  40 ,  46  are blunted to minimize the chance of snagging or puncturing the tissues that they may contact. The shaft  36  is encompassed by a sheath  50 , as are portions of the prongs  38 ,  44 . The outer surface of the sheath  50  may be roughened to increase friction at the surface of the sheath  50 , and make it easier to grip. The interior of the sheath  50  is shaped such that the sheath  50  may move forward (i.e., toward the prongs  38 ,  44 ) or backward (i.e., away from the prongs  38 ,  44 ) along the shaft  36  and the prongs  38 ,  44 , but the shaft  36  and the prongs  38 ,  44  may not rotate within the sheath  50 . A handle  52  may be provided at the end of the shaft  36  opposite the prongs  38 ,  44  such that the shaft  36  and the prongs  38 ,  44  may be held in place while the sheath  50  is moved. The prongs  38 ,  44  are resilient and are flared such that the free ends  40 ,  46  move toward from each other as the sheath  50  is moved forward from its position in  FIG. 4  to its position in  FIG. 5 . 
         [0035]    As with the hook-shaped device  10 , the various components of the two-pronged device  34  may be may be made of a biologically inert metal, a rigid plastic, or other rigid material. The two-pronged device  34  is not intended to penetrate, the wall  20  of the vaginal vault  22 , so it is less likely that the two-pronged device  34  would be left in place after use. Therefore, there would be less advantage in making components of the two-pronged device  34  out of biodegradable polymers. 
         [0036]    A preferred application of the two-pronged device  34  to the obstruction of the uterine artery  24  is illustrated in  FIGS. 6 through 8 . The method used is non-invasive and, thus, does not require an incision through the wall  20  of the vaginal vault  22 . 
         [0037]    Referring to  FIGS. 6 and 7 , the device  34  is advanced with the prongs  38 ,  44  extended toward the vaginal vault  22  in an area near the uterine artery  24 . The prongs  38 ,  44  press against the wall of the vault  22 , stretching portions  54 ,  54 ′ of the wall so that they extend past the uterine artery  24  on both sides. When the bent portions  42 ,  48  are positioned adjacent the uterine artery  24 , the sheath  50  is moved forward so that the free ends  40 ,  46  press the stretched portions  54 ,  54 ′ of the wall  20  of the vaginal vault  22  against each other, in such a manner that they entwine the uterine artery  124  (see  FIG. 7 ). As can be seen in  FIG. 7 , the bent portions  42 ,  48  of the prongs  38 ,  44  are sized and shaped to surround a portion of the wall  20  of the vaginal vault  22  while it is wrapped around the uterine artery  24 . 
         [0038]    Referring to  FIG. 8 , the entire device  34  is then rotated so that it twists the wall  20  of the vaginal vault  22  and the uterine artery  24  such that the blood flow through the artery is completely blocked. The prongs  38 ,  44  are prevented from rotating back to their original position by the internal structure of the sheath  50 , which itself is held in position through a friction fit within an optional pessary  56  that surrounds the cervix  26 , or by a catch (not shown) inside of the pessary  56 . The two-pronged device  34  may be provided separately from the pessary  56  and inserted therethrough, or they may be provided together as a single device. Suitable catches include one or two-sided clamps, clips or other grasping devices. 
         [0039]    As discussed above with regard to the hook-shaped device  10 , the two-pronged device  34  is held in position for the length of time needed to degenerate or kill the fibroid, after which the two-pronged device  34  is rotated so as to untwist the wall  20  of the vaginal vault  22 , and thus untwist the uterine artery  24 . The sheath  50  is then moved backward to enable the free ends  40 ,  46  to move away from each other. The two-pronged device  34  may be shaken gently to release the free ends  40 ,  46  of the prongs  38 ,  44  from the vaginal wall  20 , if necessary. Means for determining the position of the two-pronged device  34  or the flow of blood through the uterine artery  24  would be the same as those discussed with regard to the hook-shaped device  10 , discussed above. 
         [0040]    It should be understood that the embodiments described herein are merely exemplary and that a person skilled in the art may make many variations and modifications thereto without departing from the spirit and scope of the present invention. For example, the method of the present invention is meant to include the use of any device that is capable of catching and twisting a blood vessel to reduce the flow of blood therethrough. All such variations and modifications, including those discussed above, are intended to be included within the scope of the invention, which is described, in part, in the claims presented below.