Abstract:
Occlusion devices and methods for occluding fallopian tubes which take effect promptly after deployment. The occlusion device comprises an occluding element and a fixation element. In one embodiment, the occluding element is deployed within the fallopian tube and in another embodiment, the occluding element is external to the fallopian tube.

Description:
CROSS-REFERENCE TO RELATED INFORMATION 
   The application claims priority to U.S. provisional patent application Ser. No. 60/821,238 filed on Aug. 2, 2006, which is fully incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   The present invention relates generally to contraception, and more particularly, to intrafallopian contraceptive devices and non-surgical methods for their delivery. 
   The art to which the present invention is directed is described in United State Published Patent Application No. 2005/0172972, the entirety of which is incorporated herein by reference. 
   SUMMARY OF THE INVENTION 
   The device of the present invention comprises a cap and a body. The body is provided with expandable attachment means which collapse when the device is placed under axial stress. When the stress is removed, the compressed attachment means expand. The device can be used to occlude the fallopian tube without perforating it. 
   The device, and its deployment in this manner, achieve virtually instant sterilization. 

   
     DESCRIPTION OF THE DRAWINGS 
       FIGS. 1 and 2  show the occluder without a delivery device with the body in the extended, stressed condition in  FIG. 1  and in the unstressed shortened condition in  FIG. 2 . 
       FIGS. 3 and 4  show the occluder device in combination with the deployment device, with the attachment means collapsed in  FIG. 3  and expanded in  FIG. 4 . 
       FIG. 5  shows the device after installation in the fallopian tube. 
       FIG. 6  shows an alternate embodiment of the occlusion device of the present invention which comprises an occluder element and a fixation element in which the fixation element comprises a looped wire. 
       FIG. 7  shows a variation of the embodiment of  FIG. 6  in which the fixation element comprises two looped wires. 
       FIG. 8  shows a fixation enhancing attachment which may be added to the fixation element. 
       FIG. 9  is a schematic illustration of a portion of the deployment means used to deliver the occlusion device into the fallopian tube. 
       FIGS. 10A-C  are sequential illustrations which show the several stages of deployment of the occlusion device. 
       FIG. 11  is a schematic illustration which shows the occlusion device of  FIG. 6  after it has been deployed in a fallopian tube. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As shown in  FIG. 1 , the occluder  1  comprises a cap  2 , a body  3 , attachment device  4  and plug  5 . Cap  2  is provided with through hole  6 . As shown, the body is in an extended, stressed condition and expansion means  4  is in a collapsed condition. 
     FIG. 2  shows occluder  1  with attachment means  4  in their expanded configuration after the lengthening stress on body  3  has been removed. 
   As can be seen in a comparison of  FIG. 2  with  FIG. 1 , the lengthening of body  3  is accomplished by exerting axial force on plug  5 . When that force is removed, plug  5  assumes its unstressed shorter configuration as shown in  FIG. 2  and plug  5  moves into through hole  6  such that there is no longer an opening in cap  2 . The body  3  may be made of nitinol metal while cap  2  and plug  5  may be made from a suitable polymer material. 
     FIG. 3  shows the occluder in combination with a delivery means comprising grasper  7  and plunger  8 . In the configuration shown in  FIG. 3 , plunger  8  pushes on plug  5  to cause the body  3  to assume its extended, stressed configuration and causes grasper  7  to engage cap  2 . 
   As shown in  FIG. 4 , when plunger  8  is retracted, body  3  shortens and attachment members  4  assume their expanded configuration. This shortening of body  3  moves plug  5  into the through hole  6  in cap  2 . 
     FIG. 5  shows the occluder device after installation with attachment means  4  engaging the wall of fallopian tube  9  and cap  2  sealing the fallopian tube at uterus wall  10 . Once deployed, the device achieves virtually instant sterilization. 
   An alternate embodiment of the occluder device of the present invention is shown in  FIG. 6 . In this embodiment, the occluder device has a distal portion which is the occluder element and a proximal portion which is the fixation element. The occluder element comprises a tubular portion  11  which is preferably fabricated from a soft polymeric or elastomeric material which has a distal end region  12  with a relatively narrow diameter. Located proximally to the distal region  12  are a series of spaced ribs  13 - 16  which have progressively increasing diameters. The portion of the occluder element extending from the narrow diameter tip to the largest diameter rib  16  may be hollow or solid. The number of ribs shown in  FIG. 6  is exemplary only and there may be a lesser or greater number of ribs. Each of the ribs plays a role in occluding a fallopian tube, but the largest diameter rib is the primary occluding element. A fixation element  17  which has a distal portion  18  and a proximal portion  19  extends from a point proximal to the proximal end of the occlusion element  11  to a point in the region of the distal end of the occluding element, typically in the region of ridge  16 . The distal end  18  of the fixation element may comprise an enlarged loop as shown in  FIG. 6  or may have any other suitable configuration. A proximal portion  19  of the fixation element  17  preferably bows outwardly as shown in  FIG. 6  with a straight portion  20  proximal to the bowed portion  19 . As will be described in more detail below, the bowed portion  19  of the fixation element is fabricated from a resilient or elastic material which can be deformed such that it is in alignment with straight portions  20  when constrained by a sleeve (not shown) and which will revert to its bowed configuration when the constraint is removed as shown in  FIG. 6 . Optionally, a tissue-engaging element  21  can be attached to the bowed portions  19 . For example, the fixation device may have the configuration of a flared cylinder as shown in  FIG. 6  or it can have other configurations such as a barb, hook, or other projection including the type shown as element  4  in  FIG. 2  hereof. 
     FIG. 7  illustrates an occlusion device similar to that illustrated in  FIG. 6  and the same reference numerals are used for the same elements. However, in  FIG. 7 , the illustrated embodiment has a fixation element comprising two looped wires rather than one looped wire as shown in  FIG. 6 . 
     FIG. 8  is a cross-sectional view of fixation enhancing attachment  21  which has flared ends  22 . 
   Deployment of the occlusion devices of  FIGS. 6 and 7  is accomplished by using a delivery device comprising two sleeves, an inner sleeve or tube which abuts the proximal end of occlusion element  11  and which constrains the bowed portions  19  of fixation element  17  such that they are aligned with proximal portions  20 . A second outer sleeve or tube is positioned over occlusion element  11  and over the inner sleeve such that the distal end of the outer sleeve abuts the largest diameter rib  16 . The outer sleeve is attached to a handle and is flexible. Preferably, the occlusion device is deployed in conjunction with the use of a hysteroscope which permits visualization of the target fallopian tube and which has a separate lumen adapted for delivery of the occlusion device. Thus, by first visualizing the fallopian tube and then manipulating the handle attached to the outer tube of delivery device, the occlusion device can be inserted into the fallopian tube such that, preferably, the insertion is deep enough for the proximal end  20  of the fixation device to be located within the fallopian tube. The outer and inner tubes are then removed such that the outer tube no longer contacts the occlusion device and such that the bowed portions  19  of the fixation element  17  are free to bow outwardly into contact with the tissue of the fallopian tube. If the optional fixation elements  21  are used, they will also be brought into contact with the tissue of the fallopian tube. 
   As with the device shown in  FIGS. 1-5 , the occlusion device of  FIGS. 6 and 7  will immediately occlude the fallopian tube such that the waiting time associated with other fallopian tube occluders before they are effective in occluding a fallopian tube is not required. 
   The fixation element  17  can be made out of any suitable resilient or elastic material which may be either metal or polymeric, e.g., metals such as nitinol, stainless steel, plastic, reinforced plastics or other suitable materials may be used. Among the polymeric materials which may be used are included polyimides, polyolefins, polycarbonates, polyesters, polyamides, polyurethanes, synthetic rubbers, etc. Similarly, the occlusion element can be made from a wide variety of materials. Preferably, this element is made from a relatively soft material which may be rubber, synthetic rubber, a foam material which may be fabricated from the polymers identified above or from other materials. The occlusion element may also be made from metal, but a non-metal material is preferred for most uses. 
   Furthermore, a material may be added to the outside of the occlusion element which will promote scarring, typically by physical irritation of the fallopian tube tissue or by other scarring mechanisms which may include chemical compounds, to further insure the integrity of the occlusion of the fallopian tube. 
   Shape-memory metals or polymers are preferred for fabricating the fixation element  17 . These shape-memory materials may be composites, e.g., polymers which contain particulate or other additives, such as carbon particles or fibers, and may be combinations of metal and polymer, such as a coated metal. The shape memory may be temperature dependent, i.e., actuated by heating or other energy input, or may be mechanical in nature. Such materials are well known to those skilled in the art. 
     FIG. 9  is a schematic illustration of the delivery system of the present invention. As shown, inner tube  24  compresses the bowed portions  19  of the fixation element such that the bowed portions are aligned with the proximal portions  20 . Outer sleeve  25  functions as a pusher element and is connected to a handle (not shown). The outer sleeve  25  is dimensioned so that it will fit in the additional lumen in a hysteroscope and, when pushed distally by applying force to the handle to which it is attached, will advance the occluding element into the fallopian tube. Once the desired location is achieved, outer sleeve  25  is removed. At this time, inner sleeve  24  which abuts the proximal end  23  of the occlusion element is also removed by pulling it in a proximal direction. When inner sleeve  24  is removed, bowed portion  19  of the fixation element will expand outwardly into the tissue of the fallopian tube to effectively hold the device in place. 
     FIGS. 10A-C  are sequential schematic drawings which further illustrate delivery of the occlusion device. In these drawings, element  26  is a handle which slidably receives outer sleeve  25 . When trigger  27  is pulled, it slides outer sleeve  25  proximally away from the occlusion device to deploy it in the fallopian tube. Inner sleeve  24  is then also moved proximally to release bowed portions  19  of the fixation element as shown in  FIG. 10C . 
     FIG. 11  is a schematic illustration of the occlusion element  11  deployed in fallopian tube  28  with the bowed portion  19  of the fixation element engaged with the tissue of fallopian tube  28 . In actual practice, the bowed portion  19  of the fixation element would penetrate the fallopian tube tissue and the occluder element would be large enough to cause the contour of the fallopian tube to be altered to be in a satisfactory degree of confirmation to the shape of the occluder device to assure effective occlusion. 
   The foregoing description of specific embodiments exemplifies the present invention and is but one embodiment thereof. Thus, it is to be understood that the scope of this invention is defined solely by the appended claims.