Abstract:
An implantable sterilization device may include a ring having an inner diameter, a core slidable through the inner diameter of the ring, and a tissue securing element, at least part of which is positioned between the ring and the core. A method of closing a fallopian tube may include providing a closure system including a handle, a flexible shaft connected to the handle, and a sterilization device detachably connected to the flexible shaft, inserting the flexible shaft into the lumen of the fallopian tube and advancing the flexible shaft into the lumen; compressing a portion of the wall of the fallopian tube with the sterilization device to secure the sterilization device relative to the fallopian tube, blocking the lumen of the fallopian tube with the sterilization device; and separating the sterilization device from the tube.

Description:
FIELD OF THE INVENTION 
   The invention generally relates to a surgical tool and method, and more specifically to a surgical tool and method for occluding a fallopian tube. 
   BACKGROUND 
   At the present time, satisfactory options for female birth control are limited. Nonsurgical methods such as birth control pills and other pharmaceutical solutions rely on the user to remember to take the medication. Further, pharmaceuticals are simply unaffordable or inaccessible to many women around the world. The most common surgical method for female birth control is tubal ligation. While effective, this surgery is highly invasive, painful, and cosmetically undesirable. Although less invasive surgical techniques and devices have been proposed for female sterilization, they have generally proven either disastrous (for example, the intrauterine device (IUD)) or less than optimally effective. The more successful systems attempt to close the fallopian tube, but require tissue ingrowth into a coil or other device, or growth of scar tissue as a result of treatment with heat, cold, RF or chemicals, such that sterilization follows the procedure several months later at a time that is not known to the patient. That is, sterilization is not immediate, but instead relies on the healing response of the body. Further, an invasive diagnostic procedure to confirm closure may be required. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a closure system that includes a deployment mechanism and a sterilization device. 
       FIG. 2  is a perspective cutaway view of the sterilization device in a first configuration. 
       FIG. 3  is a perspective cutaway view of the sterilization device in a second configuration. 
       FIG. 4  is a side cutaway view of the sterilization device in the second configuration. 
       FIG. 5  is a perspective cutaway view of the sterilization device in a third configuration. 
       FIG. 6  is a perspective cutaway view of the sterilization device in a fourth configuration. 
       FIG. 7  is a perspective cutaway view of the sterilization device in a fifth configuration. 
       FIG. 8  is a side cutaway view of the sterilization device in the fifth configuration, after its release from the deployment mechanism. 
   

   The use of the same reference symbols in different figures indicates similar or identical items. 
   DETAILED DESCRIPTION 
   Closure System 
   Referring to  FIGS. 1-2 , a closure system  1  may include an implantable sterilization device  2  connected to a deployment mechanism  3 . The deployment mechanism  3  includes a flexible tube  4  that has a lumen defined longitudinally therethrough. The tube  4  advantageously has an outer diameter of two millimeters or less, such that the tube  4  may be received easily in both a fallopian tube and in the working channel of a conventional endoscope. However, the tube  4  may have any other suitable diameter. The tube  4  extends between the sterilization device  2  and the handle  5  of the deployment mechanism  3 . The handle  5  may be a standard trigger grip, or may be configured in any other suitable manner. The sterilization device  2  is actuable by and separable from the deployment mechanism  3  in any suitable manner, as described in greater detail below. 
   Referring to  FIG. 2 , the sterilization device  2  is shown in a first, predeployment configuration. The sterilization device  2  includes a ring  20  that is held by the tube  4  of the deployment mechanism  3 . Referring also to  FIG. 8 , at least part of the ring  20  may extend distally outward from the tube  4 . Alternately, the ring  20  may be held completely within the tube  4 , or may be positioned completely outside the tube  4 . The tube  4  may retain the ring  20  in any suitable manner, such as by a friction fit. The ring  20  may be detachably connected to the tube  4 . The sterilization device  2  may include a core  6  that extends distally outward from the tube  4 . The core  6  may be configured in any suitable manner. As one example, the core  6  includes an atraumatic tip  8  located distal to the tube  4 , and a shaft  12  extending proximally into the lumen of the tube  4 . The atraumatic tip  8  may be curved in a hemispherical or other convex manner, coated in atraumatic material, or otherwise configured such that advancement of the distal end of the core  6  through the fallopian tube does not substantially engage or damage tissue of the fallopian tube. The atraumatic tip  8  is advantageously two millimeters in diameter or less, such that the atraumatic tip  8  can be received easily in both a fallopian tube and in the working channel of a conventional endoscope. However, the atraumatic tip  8  may have any other suitable diameter, and/or any other suitable shape or profile. Proximal to the atraumatic tip  8 , the core  6  may include a deformation surface  10  that may be curved in a concave manner and decrease smoothly in diameter along the proximal direction. Alternately, the deformation surface  10  of the core  6  may be shaped in any other suitable manner. Referring also to  FIG. 5 , one or more channels  18  may be defined in the deformation surface  10 . The channels  18  may extend generally longitudinally and may have a generally rectangular cross section. The channels  18  may be generally evenly spaced along the circumference of the deformation surface  10 . Alternately, the channels  18  may be spaced, shaped, oriented and/or configured differently, or omitted altogether. Referring also to  FIG. 2 , proximal to the deformation surface  10 , the core  6  may include a shaft  12  that may have a generally constant diameter. The shaft  12  may extend into the lumen of the tube  4 . 
   The sterilization device  2  includes a tissue control element  14  that may be configured in any suitable manner. As one example, the tissue control element  14  may include a plurality of tines  16  with sharpened distal ends, where those tines  16  extend in the proximal direction into the tube  4 . The tines  16  may be connected to one another, or at least one tine  16  may be independent of the others. The tines  16  may be oriented such that their distal ends are initially positioned on or adjacent to the deformation surface  10 , proximal to the atraumatic tip  8 . However, the tines  16  may be configured and/or oriented in any other suitable manner. At least part of at least one tine  16  may be held within a corresponding channel  18  on the deformation surface  10 . The tissue control element  14  may be fabricated from any suitable biocompatible material, such as stainless steel, nickel-titanium alloy, or a nonmetallic material. The tissue control element  14  may be plastically deformable, elastically deformable, superelastically deformable, or otherwise deformable. As another example, the tissue control element  14  may be fixed to the core  6 , and include tines  16  oriented generally proximally. If so, the tines  16  may be fixed to the deformation surface  10 . As another example, the tissue control element  14  may omit the tines  16  and assume another configuration. As another example, the tissue control element  14  may be omitted from the sterilization device  2 . 
   Referring also to  FIG. 8 , the tines  16  of the tissue control element  14 , and/or a portion of the tissue control element  14  connected to the tines  16 , may extend proximally through the ring  20 . The tines  16  and/or other portion of the tissue control element  14  may be fixed to the ring  20 , compressed by the ring  20 , or otherwise associated with the ring  20 . Optionally, the tines  16  and/or other portion of the tissue control element  14  that extend proximal to the ring  20  may continue proximally until terminating at or within a cap  22 . The tines  16  and/or other portion of the tissue control element  14  may be connected to the cap  22  in any suitable manner, such as by molding, by friction fit, by adhesive or by welding. The cap  22  may be spaced apart from and located proximal to the ring  20 . The cap  22  may be positioned at a substantially fixed distance relative to the ring  20 . Alternately, the ring  20  and cap  22  may be parts of a continuous assembly during part or all of the deployment of the sterilization device  2 . 
   Operation 
   To begin the procedure, a standard endoscope may be introduced through the patient&#39;s cervix into the uterus, such that the distal end of the endoscope is placed in a position to view the junction of the cervix and uterus. Referring to  FIG. 1 , the sterilization device  2  and part of the tube  4  are then advanced through the patient&#39;s cervix into the uterus, and then into the fallopian tube. Advantageously, the sterilization device  2  and part of the tube  4  are advanced into the fallopian tube through the working channel of the endoscope. However, the closure system  1  may be utilized with an endoscope that does not have a working channel, such that the sterilization device  2  is advanced into the fallopian tube outside of the endoscope. As another example, an endoscopic viewing system may be integrated with the sterilization device  2 . Optionally, one or more indicia may be defined on the tube  4  to provide feedback to the user as to the depth of insertion of the tube  4  into the fallopian tube. Such indicia may include one or more visible lines on the surface of the tube  4 , one or more radio-opaque structures placed in or on the tube  4 , or any other suitable indicia. The user may view the indicia via the endoscope, a fluoroscope or other viewing device, such that the tube  4  may be advanced into the fallopian tube until a particular indicia reaches the junction between the fallopian tube and the uterus. The atraumatic tip  8  of the core  6  at the distal end of the sterilization device  2  substantially minimizes damage to the interior of the fallopian tube  24  as the sterilization device  2  moves through the lumen  26 . After the sterilization device  2  has been moved to the desired position within the lumen  26  of the fallopian tube  24 , motion of the sterilization device  2  stops. 
   Referring also to  FIG. 2 , the sterilization device  2  is in an initial position when it moves into the lumen  26  of the fallopian tube  24 . In that initial position, the distal end of the sterilization device  2  is spaced apart from the ring  20  by a first distance. Referring also to  FIG. 1 , the user then actuates the handle  5  of the deployment mechanism  3 . As described above, the handle  5  may include a trigger grip, knob, and/or any other suitable actuation mechanism. Referring also to  FIGS. 3-4 , as the user actuates the handle  5 , the tissue control element  14  is urged distally in any suitable manner. As one example, a cable (not shown) or other force transmission element extends through the lumen of the tube  4  and engages the tissue control element  14 . As another example, the tissue control element  14  itself may extend along the lumen of the tube  4  to the handle  5 , where the tissue control element  14  is later frangible at or near the boundary of the sterilization device  2  to allow separation of the sterilization device  2  from the closure system  1 . Distal motion of the tissue control element  14  urges the tines  16  against the deformation surface  10  of the core  6 . Advantageously, referring also to the view of the core  6  seen in  FIG. 5  without reference to its position in that figure, one or more of the tines  16  slide along a corresponding channel  18  defined in the deformation surface  10 . Each channel  18  guides the corresponding tine  16  in a desired direction relative to the core  6 . As each tine  16  moves distally along the deformation surface  10 , the curvature of the deformation surface  10  causes the distal end of that tine  16  to move at least in part in a direction away from the longitudinal centerline of the sterilization device  2  and into the tissue of the wall of the fallopian tube  24 , and then penetrate the wall of the fallopian tube  24 . As used in this document, the words “penetrate,” “penetrates” and “penetration” are defined to mean motion of a structure completely through the wall of the fallopian tube  24 . Alternately, at least one tine  16  enters partially into the wall of the fallopian tube  24  but does not penetrate the wall of the fallopian tube  24 . Alternately, where the tissue control element  14  does not utilize tines  16 , the tissue control element  14  is otherwise deformed against the deformation surface  10  of the core  6  upon actuation of the handle  5 , and may or may not penetrate the wall of the fallopian tube  24 . Alternately, the tissue control element  14  is otherwise deformed or manipulated upon actuation of the handle  5 . 
   Next, referring also to  FIG. 5 , as the user continues to actuate the handle  5 , the core  6  is advanced distally relative to the ring  20  and the tissue control element  14  in any suitable manner. As one example, a force transmission element (not shown) extends through the lumen of the tube  4  and engages the shaft  12  of the core  6  to urge the core  6  distally. As another example, the shaft  12  itself may extend along the lumen of the tube  4  to the handle  5 , where the shaft  12  is later frangible at or near the boundary of the sterilization device  2  to allow separation of the sterilization device  2  from the closure system  1 . The tines  16  may flex or move inward toward the longitudinal centerline of the fallopian tube  24  as a result, or may remain in their previous position. The tines  16  may remain in a location in which at least one tine  16  penetrates the wall of the fallopian tube  24 . Next, referring also to  FIG. 6 , the tissue control element  14  is retracted proximally. As a result, the tissue control element  14  pulls the wall of the fallopian tube  24  inward, reducing the diameter of the lumen  26 . Where the tissue control element  14  includes one or more tines  16 , the distal end of each tine  16  may be notched, configured in a fishhook-like manner, or otherwise configured such that retraction of each tine  16  causes the tines  16  to engage the outer surface of the wall of the fallopian tube  24  and draw that wall inward, instead of slipping out of the wall of the fallopian tube  24 . As the tines  16  are retracted, the distance between the distal end of each tine  16  and the ring  20  decreases, such that tissue of the wall of the fallopian tube  24  may be compressed longitudinally and bunched between the tines  16  and the ring  20 . Alternately, the tissue control element  14  may draw the wall of the fallopian tube  24  inward and/or compress it in any suitable manner, or may not draw the wall of the fallopian tube  24  inward and/or compress it at all. 
   Next, referring also to  FIG. 7 , the core  6  is retracted proximally toward the ring  20 , such that the distance between the core  6  and the ring  20  decreases. The core  6  may move proximally until it ceases motion relative to the ring  20 , in a final position. In the final position, the core  6  may be locked into place relative to the ring  20 . Such locking may be accomplished in any suitable manner. As one example, the core  6  varies in diameter along its length, such that retraction of the core  6  causes a portion of the core  6  having a diameter substantially the same as the opening in the ring  20  to enter the ring  20  and thereby lock the core  6  in place by a friction and/or interference fit. As another example, a locking feature (not shown) may be included on the core  6 , ring  20  and/or cap  22 , such that retraction of the core  6  causes engagement between locking features, or between a locking feature and the core  6 , ring  20  and/or cap  22 . As described above, tissue of the wall of the fallopian tube  24  already may be bunched between the tines  16  and the ring  20  before proximal motion of the core  6 . When the core  6  is in the final position, the distal end of the core  6  and the ring  20  may compress that bunched tissue further, and/or simply hold that bunched tissue in place. Alternately, the tissue of the fallopian tube  24  has not been compressed substantially beforehand, and motion of the distal end of the core  6  toward the ring  20  causes such compression. Compression of the tissue of the fallopian tube  24  secures the sterilization device  2  in place in the fallopian tube  24 . The sterilization device  2  is now in the closed position, in which the distal end of the sterilization device  2  is spaced apart from the ring  20  by a second distance that is less than the first distance. The walls of the fallopian tube  24  have been pulled inward toward the core  6 , bunched together, and locked in place, and the core  6  blocks the lumen  26  of the fallopian tube  24 . 
   At this time, the user may test to ensure that the sterilization device  2  is locked in place, by gently pulling on the tube  4  in the proximal direction. If the tube  4  does not substantially move, then the sterilization device  2  is locked in place, and the patient is sterilized. The closure of the fallopian tube  24  is immediate, and does not depend on a healing response from the tissue of the fallopian tube  24 . If the tube  4  does move, then the sterilization device  2  has not been locked in place, and may be withdrawn from the fallopian tube  24 , after which the user may try again with the same or a different closure system  1 . Referring also to  FIG. 8 , the tube  4  is then separated from the sterilization device  2 , leaving the sterilization device  2  in place in the fallopian  24 . The tube  4  may be separated from the sterilization device  2  in any suitable manner. As one example, the tube  4  is friction fit or interference fit to the cap  22 , such that a known force overcomes that fit and causes the tube  4  to separate from the cap  22 , where the known force is at least equal to the force that securely holds the sterilization device  2  permanently in place in the fallopian tube  24 . Such a disconnection may be referred to as a passive disconnection. Alternately, the sterilization device  2  may be disconnected from the tube  4  in any other suitable manner. The procedure is then complete. 
   While the invention has been described in detail, it will be apparent to one skilled in the art that various changes and modifications can be made and equivalents employed, without departing from the present invention. It is to be understood that the invention is not limited to the details of construction, the arrangements of components, and/or the method set forth in the above description or illustrated in the drawings. Statements in the abstract of this document, and any summary statements in this document, are merely exemplary; they are not, and cannot be interpreted as, limiting the scope of the claims. Further, the figures are merely exemplary and not limiting. Topical headings and subheadings are for the convenience of the reader only. They should not and cannot be construed to have any substantive significance, meaning or interpretation, and should not and cannot be deemed to indicate that all of the information relating to any particular topic is to be found under or limited to any particular heading or subheading. Therefore, the invention is not to be restricted or limited except in accordance with the following claims and their legal equivalents.