Abstract:
The anastomosis devices of the invention advantageously provide reinforcement structures or components that increase the strength and/or flexibility of the device. These features can be especially beneficial to protect the integrity of the installation of the device within a patient to facilitate the healing process. These features may provide resistance to tearing or ripping of the catheter body or sheath by the tissue approximating structures and/or may provide strength in other areas of the catheter body. The anastomosis devices of the invention may further include method and devices for placing markers on the anastomosis device to facilitate accurate placement of the device within the patient.

Description:
CLAIM FOR PRIORITY  
       [0001]     The present application claims priority to U.S. provisional patent application No. 60/654,438, filed Feb. 18, 2005, and entitled “Anastomosis Device Catheter and Sheath Constructions.” The identified provisional patent application is here incorporated by reference. 
     
    
     TECHNICAL FIELD  
       [0002]     The invention relates to devices used for performing anastomosis and other related surgical procedures, including urethral procedures that involve reconnecting urethra and bladder tissues after a radical prostatectomy, vesico-urethral anastomosis, and end-to-end urethral anastomosis.  
       BACKGROUND OF THE INVENTION  
       [0003]     Anastomosis procedures are required for connecting or re-connecting certain body tissues, e.g., as part of a surgical procedure. The tissues may be part of a body lumen such as a blood vessel, intestinal or other digestive system tissue, or tissues relating to the urinary system. As one example, in a radical prostatectomy, a surgeon removes all or most of a patient&#39;s prostate. Because the urethra travels through the prostate immediately before reaching the bladder, the upper part of the urethra is also removed with the surgery. The procedure leaves a severed urethral stump and a severed bladder neck. To restore proper urinary functions, the bladder and the urethra must be reconnected.  
         [0004]     Conventionally, a surgeon may execute delicate suturing operations with tiny, fine needles to reconnect these or other anatomical bodies. However, installation of sutures with a needle to connect severed tissues can be a difficult and technique-sensitive task. Many factors can make the task difficult, including a very small amount of tissue to work with (e.g., at the urethral stump and at the bladder neck), and proximal sensitive tissues such as ureters at a bladder and a proximal nerve bundle and sphincter at a urethral stump. These factors result in complicated and delicate suturing procedures that, if not performed properly, could result in complications such as leakage, difficulty in healing or failure to heal, or specific conditions such as incontinence or impotence.  
         [0005]     To reduce the risks involved in conventional suturing procedures, anastomosis devices have been developed that include a drainage feature and tissue approximating structure that allow for reconnection of tissues without using traditional sutures. Examples of such anastomosis devices are described, for example, in Applicants&#39; co-pending U.S. patent applications having Ser. No. 10/646,383, filed Aug. 21, 2003, entitled “Anastomosis Device and Related Methods”; Ser. No. 10/919,545, filed Aug. 16, 2004, entitled “Anastomosis Device and Related Methods”; and Ser. No. 10/919,775 filed Aug. 16, 2004, entitled “Anastomosis Device and Related Methods”, all of which are incorporated herein by reference in their entireties. These anastomosis devices advantageously use tissue approximating structures to reconnect severed tissues during anastomosis procedures, which can both reduce the risks during the surgical procedure and also provide a significant reduction in the amount of time required to perform certain anastomosis procedures. Because the anastomosis device will typically be surgically positioned within the patient for a significant period of time (e.g., while the healing process takes place), there is a need for the device to be sufficiently strong and flexible to accommodate the various stresses to which the device may be subjected while positioned within the patient.  
       SUMMARY OF THE INVENTION  
       [0006]     Anastomosis devices and related surgical tools and external connecting devices of the invention preferably include an elongated body, tissue approximating structures that extend from the elongated body, such as one or multiple sets of tines, mechanisms for actuating the tissue approximating structures, a drainage lumen that may extend as a channel through the length of the elongated body and that communicates at its distal end with a drainage aperture, and a balloon at or adjacent to the distal end of the device. The actuating mechanisms for the tissue approximating structure are located generally near a proximal end of the device and may include any of a wide variety of actuation configurations that can provide for extension and retraction of the tissue approximating structure, as desired. The reinforcement configurations described herein may apply to any of these types of anastomosis devices that may remain within a patient for a significant time period due to the use of the tissue approximating structures. However, many of the embodiments of the invention may also apply to anastomosis devices that are differently configured, such as a device that does not include a balloon, for example.  
         [0007]     One exemplary configuration for the tissue approximating structure includes two sets of tines spaced from each other along the length of the catheter body that can be extended and retracted from the catheter body. In this example embodiment, each of the sets of tines is controlled by an actuation mechanism that is attached to the anastomosis device and is positioned outside the patient&#39;s body. Each of the sets of tines may be simultaneously or sequentially moveable, as desired.  
         [0008]     The anastomosis devices of the invention advantageously provide reinforcement structures or components that increase the strength and/or flexibility of the device. These features can be especially beneficial to protect the integrity of the installation of the device within a patient to facilitate the healing process. These features may provide resistance to tearing or ripping of the catheter body or sheath by the tissue approximating structures and/or may provide strength in other areas of the catheter body.  
         [0009]     The anastomosis devices of the invention may further include method and devices for placing markers on the anastomosis device to facilitate accurate placement of the device within the patient. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     The invention will be further explained with reference to the appended Figures, wherein like structure is referred to by like numerals throughout the several views, and wherein:  
         [0011]      FIG. 1   a  is a perspective view of an anastomosis device including a cable or wire within the catheter shaft;  
         [0012]      FIG. 1   b  is a cross-sectional end view of the device of  FIG. 1   a;    
         [0013]      FIG. 1   c  is a cross-sectional front view of a portion of an anastomosis device having a reinforcing structure bonded within a lumen of the device;  
         [0014]      FIG. 2  is a perspective view of a portion of an anastomosis device including a strain relief feature;  
         [0015]      FIG. 3  is a cut-away perspective view of the device of  FIG. 2 ;  
         [0016]      FIG. 4   a  is a perspective view of a tip portion of an anastomosis device including an integrated mesh in a connective sheath;  
         [0017]      FIG. 4   b  is a top view of another configuration of mesh in a portion of an anastomosis device;  
         [0018]      FIG. 5  is a perspective view of a tip portion of an anastomosis device similar to that of  FIG. 4   a , but including a larger mesh area;  
         [0019]      FIG. 6   a  is a perspective view of a tip portion of an anastomosis device including reinforcement extension areas;  
         [0020]      FIG. 6   b  is a top view of the device of  FIG. 6   a;    
         [0021]      FIG. 7   a  is a perspective view of a tip portion of an anastomosis device having a force-transmitting inner construction;  
         [0022]      FIG. 7   b  is a schematic top view of the inner area of a portion of the tip of  FIG. 7   a.   
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0023]     Referring now to the Figures, wherein the components are labeled with like numerals throughout the several Figures, and initially to  FIGS. 1   a  and  1   b , one exemplary embodiment of an anastomosis device  10  is illustrated, which includes an elongated catheter shaft  12  having a central drainage lumen  14  that extends generally along the length of catheter shaft  12 . Catheter shaft  12  further includes an actuation wire lumen  16  through which an actuation wire for the tissue approximating structure can extend, and an inflation lumen  18  used for inflation and deflation of a balloon near the tip of the device. Catheter shaft  12  further includes at least one cable or wire  20  that acts as a reinforcement structure and extends through the wall of catheter shaft  12  along at least part of its length. This cable or wire  20  is made of a material that provides added strength to the device  10  to prevent or minimize stretching or deformation of catheter shaft  12  during manipulation of device  10  and/or to protect the integrity of the device if it is subjected to unanticipated loads, such as impact loads. Thus, cable or wire  20  is preferably chosen or designed to be as thin and lightweight as possible so as to not add unnecessary weight or bulk to device  10 , while still providing the desired amount of protection for the device. In addition, cable or wire  20  should be of a size and shape that maintains a relatively flexible catheter shaft  12  for patient comfort. More than one cable or wire  20  may be used in a particular catheter shaft  12 , where multiple wires  20  within a single device may be spaced from each other within the wall of catheter shaft  12 . Cable or wire  20  may be coextruded within the wall of catheter shaft  12 , or may instead extend through a central opening of catheter shaft  12 . In a further alternative, cables or wires  20  may be located on the outside of catheter shaft  12  and may be secured to shaft  12  by adhesive mechanical attachment, wrapping of wire  20  about shaft  12 , and the like. Cables or wires  20  may be solid lengths of material such as metal, plastic, fabrics, woven materials, and the like, or may instead be hollow tubular structures. Each cable or wire  20  may comprise more than one piece of the same or different materials that are woven or otherwise attached to each other along their lengths.  
         [0024]      FIG. 1   c  is a cross-sectional view of a section of wire or cable  22  that may be have a structure as described above relative to  FIGS. 1   a  and  1   b . Wire or cable  22  extends through a lumen  24  along at least a portion of a catheter shaft, and may optionally include a ball or enlarged portion  26  at one or both of its ends. This embodiment further includes an adhesive  28  within at least a portion of lumen  24  for securing wire  22  so that it cannot move relative to lumen  24 . If wire  22  includes an enlarged portion  26 , this enlarged portion  26  can provide an anchor point to help prevent movement of wire  22  along the length of the catheter shaft. Adhesive  28  may optionally be provided in a color or material that is visible or otherwise detectable to determine the amount of adhesive  28  placed within lumen  24 . In this way, the manufacturer can detect when an adequate amount of adhesive  28  is added to lumen  24 , which can also prevent overflow of adhesive from lumen  24  that may occur with the addition of too much adhesive.  
         [0025]      FIGS. 2 and 3  illustrate a catheter funnel  30  of an anastomosis device that would typically be located at the proximal end of the anastomosis device. This funnel  30  includes an integrated strain relief portion  32  that allows for compression and extension of funnel portion  30  when the device is subjected to external loads. Relief portion  32  is illustrated as an accordion-like section of the device between two sections that are generally not expandable or compressible. Relief portion  32  may be as long or short as desired, where a longer relief portion  32  will provide additional flexibility to the device. Relief portion  32  should have sufficient radial strength to keep it from collapsing on itself or kinking during or after placement within a patient. In addition, relief portion  32  should be long enough that it allows for a normal amount of compression or extension of the device when subjected to loads. Relief portion  32  may be a portion of funnel  30  that is an integral to funnel  30  (e.g., it is integrally molded or formed with the other portions of funnel  30 ). Alternatively, relief portion  32  may be a separate section that is attached at one or both ends to remainder of funnel  30 . Further, relief portion  32  may be provided in a different configuration than that shown in order to provide a different flexibility for this portion as compared to the portions on either side of it. For example, relief portion  32  may be configured as an elongated tube that is made of a material that is more flexible or elastic than the areas of funnel  30  to which it is attached, thereby providing the desired strain relief properties to funnel  30 .  
         [0026]     Referring now to  FIG. 4   a , a tip portion  40  of an anastomosis device is illustrated, which includes a catheter shaft  42  and a plurality of extending tissue approximating structures or tines  46 . Tip portion  40  further includes a connective sheath  44  having two rings of mesh  48  in the general area of the extending tines  46 . Rings of mesh  48  are spaced from each other along the length of sheath  44 , and are preferably positioned to include most or all of the areas of sheath  44  through which tines  46  may extend. That is, if the device includes two sets of tines  46 , one ring of mesh  48  is preferably provided for each set of tines  46 , although it is possible that less rings of mesh  48  are provided than the number of sets of tines  46 . Mesh  48  adds support to the structure in the areas where the tines extend through sheath  44  and thus may be provided in any area of the anastomosis device through which tines extend (e.g., through the catheter shaft if this is the area of the device that includes extending tines). In this way, the areas of mesh  48  can prevent or minimize tearing or other damage to sheath  44  or catheter body that may occur if it is subjected to certain forces that are placed on the anastomosis device. In addition, mesh  48  can provide sufficient additional structure to the device to prevent sheath  44  from stretching. Mesh  48  may be integrated into connective sheath  44 , as shown in  FIG. 4   a . Alternatively, mesh portions  50  may be overmolded or bonded to a connective sheath, such as to the portion of a connective sheath  52  illustrated in  FIG. 4   b . Sheaths  44 ,  52  may be made of a flexible material, such as silicone, and mesh portions  48 ,  50  are preferably made of a relatively lightweight and bendable material, such as metal, plastic, natural or synthetic fibers, or the like. Mesh portions  48 ,  50  may also have a wide variety of configurations, such as a woven or knitted construction, that allow for relatively easy penetration of any tissue approximating structures.  
         [0027]      FIG. 5  illustrates another tip portion  60  of an anastomosis device, which includes a catheter shaft  62  and a plurality of extending tissue approximating structures or tines  64 . Tip portion  60  further includes a connective sheath  66  having a single elongated area of mesh  68  that extends along the length of sheath  66  for a distance that is long enough to encompass all of the sets of tines  64  that extend from sheath  66 . In this embodiment, mesh  68  extends along the entire length of sheath  66 , which thereby includes both sets of tines  64 . As with the mesh reinforcements provided in  FIGS. 4   a  and  4   b , mesh  68  preferably provides sufficient additional structure to the device to prevent sheath  66  from stretching, and also preferably is strong enough to prevent or minimize tearing or other damage to sheath  66  or catheter body that may occur if it is subjected to certain forces that are placed on the anastomosis device. Mesh  68  may either be incorporated into connective sheath  66  or be bonded or overmolded to connective sheath  66 . Further, mesh  68  may be provided in any area of the anastomosis device through which tines extend (e.g., through the catheter shaft or some other component of the device if this is the area of the device that includes extendible tines).  
         [0028]     Another tip portion  70  of an anastomosis device is illustrated in  FIGS. 6   a  and  6   b , which includes a catheter shaft  72  and a plurality of extending tissue approximating structures or tines  74 . Tip portion  70  further includes a connective sheath  76  having reinforced portions  78  in the area through which tines  74  extend from its outer surface. As shown, reinforced portions  78  may be extending rings of material that are thicker than surrounding sheath  76 . The height, width, and thickness of portions  78  may be similar or different from the illustrated portions  78 , but should preferably provide a desired additional strength to the sheath that helps to prevent or minimize tearing or other damage to sheath  76  in the areas where tines  74  extend through sheath  76 . Portions  78  may either be incorporated into the connective sheath  76  or be bonded or overmolded to connective sheath  76 . Again, the reinforced portions may be provided in any area of the anastomosis device through which tines extend, such as through the catheter shaft if this is the area of the device that includes extendible tines.  
         [0029]      FIG. 7   a  illustrates a tip portion or assembly  80  of another embodiment of an anastomosis device, which includes a catheter shaft  82  and a connective sheath  84 . Tip portion  80  comprises a flexible core  86  (also illustrated in  FIG. 7   b ) configured as an elongated tubular portion  88  with a flanged tip  90  at one end. Flanged tip  90  is designed to mate or interlock with an opening  94  of a tip  92 . In this way, force that is exerted on the bottom of a balloon when it is inside the patient will be transmitted along the length of tip assembly  80  and back to catheter shaft  82 . This transmission of force can therefore minimize the forces on the portions of assembly  80  that can include tissue approximating structures or tines, for example. Flexible core  86  may be configured with differently sized and shaped tubular portions and flanged tips to provide a similar force transmission. Of course, the tip would need to be designed to mate with the portions of the flexible core that would be inserted within it.  
         [0030]     The anastomosis devices of the invention may further include methods and devices for placing markers on the anastomosis device to facilitate accurate placement of the device within the patient. For one example, tissue approximating structure markers can be used to indicate the location from where the tissue approximating structures expand or extend. These markers could be differentiated visually, such as with color, radiographically, echogenically, or the like. For another example, luminal markers can be used to indicate the locations of the various lumens within a device. These markers could also be differentiated visually, such as with color, radiographically, echogenically, or the like. For another example, directional markers can be used to indicate if and when the tissue approximating structures have been deployed or retracted. These markers could be visual, tactile, audible, or detectable in any other manner. These directional markers can also correspond to the color of other areas of the device, such as the areas where the tine sets are located, so that the user can determine which of multiple sets of tines are deployed or retracted at a given time.  
         [0031]     A particular anastomosis device may include one or a combination of the structures and devices described above to reinforce or otherwise enhance the flexibility, strength or other properties of a device, as desired. The choices may be made to protect the device from the most likely forces or strains that may occur, thereby preventing or minimizing damage to the anastomosis device and/or injury or discomfort to the patient.  
         [0032]     In a related embodiment, a surgical tool is disclosed that is adapted to include the strain relief feature described above for connecting external devices to external tissues of a human or animal body. The strain relief features described herein are also applicable to, but not limited to, other external communicating medical devices or tools that may include Foley catheters, dialysis ports, venous access devices, and the like.  
         [0033]     The invention has now been described with reference to several embodiments thereof. The foregoing detailed description and examples have been given for clarity of understanding only. No unnecessary limitations are to be understood therefrom. It will be apparent to those skilled in the art that many changes can be made in the embodiments described without departing from the scope of the invention.