Abstract:
Implantable devices such as stents, coils, implantable contraceptives, vascular plugs, vena cava filters, left atrial appendage (LAA) closure devices employing an adhesive component to assist in securing or holding the implant in place within a lumen of a patient&#39;s body.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Application Ser. No. 61/776,468 filed Mar. 11, 2013 entitled Implantable Device with Adhesive Properties, which is hereby incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to the field of implantable devices and, more particularly, to implantable devices employing an adhesive or adhesion promoting structural features for enhanced adhesion of the implantable device to body tissue and/or to other implantable devices. 
       BACKGROUND OF THE INVENTION 
       [0003]    It is often necessary to place an implantable device within a body of a patient. For example, it may be necessary to place a stent within a body duct or blood vessel, a coil within a malformation such as an aneurysm, or a contraceptive device within a fallopian tube of a patient. It is possible that the implant may undesirably move or migrate after deployment of the device at the target location. To lessen the risk of such undesirable movement, mechanical fixation components and techniques, such as hooks or staples, may be employed to couple the device to patient tissue. In aneurysm treatment, intravascular stents have been used to block coils deployed within the aneurysm from migration out of the aneurysm. 
         [0004]    Such mechanical fixation components and techniques have the disadvantage of increasing the risk that the patient tissue to which the fixation is made will be damaged. Hence, there is a need in the field for devices and methods for decreasing the risk of migration or movement of implantable devices that do not increase the risk of causing patient tissue damage. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention employs implantable devices having adhesive properties in order to assist in holding or securing one or more implantable devices in the desired position within a patient&#39;s body. According to the present invention, implantable devices, such as stents, coils, implantable contraceptives, vascular plugs, vena cava filters, left atrial appendage (LAA) closure devices, utilize adhesives and/or adhesive properties or adhesive promoting structure to hold or secure the implantable devices in place within the patient&#39;s body, for example within a patient&#39;s vasculature, body duct, or fallopian tube. 
         [0006]    In one embodiment of the present invention an implantable device utilizes an adhesive coating or adhesive surface. 
         [0007]    In another embodiment of the present invention an implantable device utilizes an adhesive that adheres or sticks selectively only to another implant or another adhesive. 
         [0008]    In another embodiment of the present invention an implantable device utilizes a semi-permeable or permeable lumen through which an adhesive is employed. 
         [0009]    In another embodiment of the present invention an implantable device utilizes one or more semi-permeable or permeable compartments formed in a surface of the implantable device, for example formed in an exterior or interior surface of the device. 
         [0010]    In another embodiment of the present invention an implantable device utilizes an adhesive which is pre-sealed or temporarily contained within a lumen or compartment of the implantable device. 
         [0011]    In another embodiment of the present invention an adhesive is delivered to a lumen or compartment of the implantable device by an injection port. 
         [0012]    In another embodiment of the present invention an adhesive is delivered to a lumen or compartment of the implantable device by an injection port and a heater is employed to detach the lumen from the implantable device. 
         [0013]    In another embodiment of the present invention an implantable device has one or more flow channels, and an adhesive is delivered to the one or more flow channels by and injection port. 
         [0014]    In another embodiment of the present invention an implantable device employs structural features, for example surface structure features, that impart non-chemical adhesion properties for retention of the implantable device within a patient&#39;s body, for example within a patient&#39;s vasculature, body duct, or fallopian tube. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    These and other aspects, features and advantages of the invention will be apparent and elucidated from the following description of embodiments of the present invention, reference being made to the accompanying drawings, in which: 
           [0016]      FIG. 1  is a cross-sectional view of a portion of an implantable device with an adhesive coating according to certain embodiments of the present invention. 
           [0017]      FIG. 2  is a cross-sectional view of a portion of an implantable device with an adhesive coating according to certain embodiments of the present invention. 
           [0018]      FIG. 3  is a cross-sectional view of a portion of an implantable device with an adhesive coating according to certain embodiments of the present invention within a blood vessel. 
           [0019]      FIG. 4  is a cross-sectional view of an implantable device with an adhesive coating according to certain embodiments of the present invention within an aneurysm. 
           [0020]      FIG. 5A  is a cross-sectional view of an implantable device with an adhesive coating according to certain embodiments of the present invention within an aneurysm. 
           [0021]      FIG. 5B  is a cross-sectional view of an implantable device with an adhesive coating according to certain embodiments of the present invention within an aneurysm. 
           [0022]      FIG. 6  is a cross-sectional view of an implantable device with an adhesive coating according to certain embodiments of the present invention. 
           [0023]      FIG. 7  is a cross-sectional view of a portion of an implantable device according to certain embodiments of the present invention. 
           [0024]      FIG. 8  is a cross-sectional view of a portion of an implantable device according to certain embodiments of the present invention. 
           [0025]      FIG. 9  is a cross-sectional view of a portion of an implantable device according to certain embodiments of the present invention. 
           [0026]      FIG. 10  is a cross-sectional view of a portion of an implantable device according to certain embodiments of the present invention. 
           [0027]      FIG. 11  is a magnified view of a flow channel system according to certain embodiments of the present invention. 
           [0028]      FIG. 12  is a cross-sectional view of a portion of an implantable device with an adhesion promoting structural feature according to certain embodiments of the present invention. 
           [0029]      FIG. 13  is a cross-sectional view of a portion of an implantable device with an adhesion promoting structural feature according to certain embodiments of the present invention. 
           [0030]      FIG. 14  is a cross-sectional view of a portion of an implantable device with an adhesion promoting structural feature according to certain embodiments of the present invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0031]    Specific embodiments of the invention will now be described with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The terminology used in the detailed description of the embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, like numbers refer to like elements. 
         [0032]    Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
         [0033]    Broadly speaking, the present invention provides devices and methods for holding and/or securing an implantable device within a lumen of a patient, for example within a patient&#39;s vasculature, fallopian tube, or other duct. These advantages are achieved by providing implantable devices that employ an adhesive component in the form of a chemical adhesive and/or adhesion promoting structural features and methods for preparing and implanting the same. The adhesive component of the implantable device enhances adhesion of the implantable device to a patient body tissue and/or to the other implantable devices. 
         [0034]    With reference to  FIGS. 1-4 , in one embodiments of the present invention the implantable device or implant  10  employs an adhesive component in the form of an chemical adhesive  12  that is coated, printed, or otherwise applied on an exterior surface of the implant  10 . The implantable device  10  may, for example, be a coil, stent, stent-graft, and/or filter. For the sake of clarity and by way of example,  FIGS. 1-4  show the generally tubular shape implants  10  in cross-section. The tubular implants are formed of one or more struts  14  that are manipulated into a coil or weave. The struts  14  are formed of one or more metal, alloy, or polymeric wires or filaments. Alternatively, such tubular shaped implants  10  are formed from of a preformed metal, alloy, or polymeric tubular element that is subsequently manipulated by laser or other form of cutting so as to form struts  14  that define apertures or windows  18  within the tubular form of the implant  10 . 
         [0035]      FIG. 1  shows a cross-sectional view of a portion of the implant  10  formed of struts  14  having rectangular or non-circular cross-sections.  FIG. 2  shows a cross-sectional view of a portion of the implant  10  formed of struts  14  having circular or oval cross-sections. The adhesive  12  is coated, printed, or otherwise applied on an exterior surface  16  of the struts  14  of the implants  10 . 
         [0036]      FIG. 3  shows a cross-sectional view of a portion of the implant  10  of  FIG. 1  deployed within a lumen of patient, for example, deployed within a patient&#39;s vasculature  2 . The direction of a flow of blood within the vasculature  2  is indicated by arrow  8 .  FIG. 4  shows a cross-sectional view of an implant  10 , such as the implant  10  of  FIG. 2 , deployed within an aneurysm  4  of a patient&#39;s vasculature  2 . 
         [0037]    The adhesive  12  is, for example, an adhesive material such as n-butyl cyanoacrylate (nBCA), a protein with adhesive properties such as the secretion of a sandcastle marine worm, or a siloxane system such as that described in Wilson et al., Biomater Sci Polymer Ed. 2005; 16(4): 449-72, which is hereby incorporated by reference in its entirety. In general, it may be advantageous to use an adhesive  12  that is reactive to temperature, pH, salinity, water, or other biological factors in order to facilitate delivery of the implant  10  into the patient&#39;s body in a non- or lower-adhesive state. Upon delivery and/or deployment of the implant  10  to the target location, the adhesive strength of the adhesive  12  increases due to, at least in part, the reactivity of the adhesive  12  to a temperature, pH, salinity, water content, or other biological factor(s) present at the target location. 
         [0038]    The adhesive can advantageously comprise a radiopaque material such as barium sulfate, tantalum powder, or iodine contrast solution so as to allow an operator to better visualize the implant  10 . 
         [0039]    The adhesive  12  is, for example, applied to the implant  10  by dipping, spraying, painting, printing or other processes known in the art. Once the adhesive  12  is applied, the implant  10  is then delivered through an implant delivery system employing, for example, a sheath or catheter and an implant detachment component. Upon deployment, the adhesive  12  of the implant  10  enhances fixation or securing of the implant  10  in the target location, thereby reducing the probability of undesirable migration of the implant  10  from the target location. 
         [0040]    In certain embodiments of the present invention, an adhesive  12  is selected that adheres selectively only to itself, self-adhering, and/or adheres selectively to a metal, alloy, or polymeric material of a non-adhesive implant, i.e. an implant that does not employ the adhesive  12 . Employing an adhesive  12  that is only or primarily self-adhering or that is selectively adhering to another implant is advantageous where multiple implants are used for treatment at a single target location, for example, for treatment of aneurysms with multiple coil implants. 
         [0041]    By way of example, according to the present embodiment,  FIG. 5A  shows an implant  10   a  employing an adhesive  12  that is deployed within an aneurysm  4 . Wherein a gap or space between the adhesive  12  of the implant  10   a  and an interior surface  6  of the aneurysm  4  depicts a lack of adhesion of the adhesive  12  to the interior surface  6  of the aneurysm  4 . In contrast, the absence of a gap or space between the adhesive  12  of the implant  10   a  and an implant  10   b  depicts the presence of adhesion between the adhesive  12  of the implant  10   a  and the adhesive  12  of the implant  10   b.    FIG. 5B  shows an implant  10   a  employing an adhesive  12  that is deployed within an aneurysm  4 . Wherein a gap or space between the adhesive  12  of the implant  10   a  and an interior surface  6  of the aneurysm  4  depicts a lack of adhesion of the adhesive  12  to the interior surface  6  of the aneurysm  4 . In contrast, the absence of a gap or space between the adhesive  12  of the implant  10   a  and a non-adhesive implant  20  depicts the presence of adhesion between the implant  10   a  and the implant  20 . 
         [0042]    The presence of a plurality of self-adhering or selectively-adhering implants at the target location adhered to one another creates a more stable mass and, thereby, prevents the plurality of implants from shifting or migrating from the target location over time. The present embodiment is also advantageous in treatment situations where there may be a need to reposition the implant and/or where there is a possibility of tearing the tissue at the target location if the implant adheres to such tissue. 
         [0043]    The adhesive  12  is, for example, an adhesive material such as n-butyl cyanoacrylate (nBCA), a protein with adhesive properties such as the secretion of a sandcastle marine worm, or a siloxane system such as that described in Wilson et al., Biomater Sci Polymer Ed. 2005; 16(4): 449-72, which is hereby incorporated by reference in its entirety. In general, it may be advantageous to use an adhesive  12  that is reactive to temperature, pH, salinity, water, or other biological factors in order to facilitate delivery of the implant  10  into the patient&#39;s body in a non- or lower-adhesive state. Upon delivery and/or deployment of the implant  10  to the target location, the adhesive strength of the adhesive  12  increases due to, at least in part, the reactivity of the adhesive  12  to a temperature, pH, salinity, water content, or other biological factor(s) present at the target location. 
         [0044]    With reference to  FIGS. 6 and 7 , in another embodiment of the present invention, an implant employs an adhesive that is temporarily and/or is semi-sealed within a portion of the implant, for example within one or more lumens or cavities formed within the implant, prior to delivery and deployment of the implant to a target location within a patient. The one or more lumens or cavities are semi-permeable to an exterior surface of the implant such that, upon deployment of the implant at the target location, the adhesive within the one or more lumens or cavities will diffuse or migrate to an exterior surface of the implant. Once at the surface, the adhesive will adhere the implant to the patient&#39;s tissue, to other implants, and/or both, and thereby assist in securing the implant at the target location. Since many adhesives such as nBCA and sandcastle-worm adhesive solidify and harden as they cure, the mechanical properties of the implant will change, thereby providing additional stability and resistance against migration or movement of the implant. 
         [0045]    More particularly, with reference to  FIG. 6 , in certain embodiments of the present invention, the adhesive  12  is pre-loaded into at least one lumen  122  formed within an implant  110  having pores or holes  124  formed therein. The size or diameter of the pores or holes  124  of the lumen  122  are selected so as to selectively control a diffusion rate of the adhesive  12  from the lumen  122 . Hence, the time in which the adhesive  12  adheres the implant  110  to the tissue and/or to other implants is controlled so as to allow an operator to deliver, deploy, and re-position the implant  110  at the target location prior to adhesion of the implant  110  to the tissue and/or to other implants. The diffusion rate may alternatively or additionally, be controlled by treating an exterior surface of the lumen  122  with a dissolvable substance such as salt. In order for the adhesive  12  to diffuse or migrate from the interior of the lumen  122 , the dissolvable substance is first dissolved from the surface to the lumen  122  by patient fluids, such as blood. 
         [0046]    The lumen  122  is formed, for example, of a polyolefin or ethylene-octene copolymer extruded under conditions resulting in the formation of micropores within the extrusion. Alternatively, the lumen  122  is formed from a polyamide that has micro-holes cut therein by an excimer laser or other cutting technique. Alternatively, the lumen  122  is formed from a polymer such as a polyolefin, Teflon, polyamide, PEEK, PET, or the like with holes cut with an appropriately sized needle or drill. 
         [0047]    The adhesive  12  employed in the implant  110  is, for example, an adhesive material such as n-butyl cyanoacrylate (nBCA), a protein with adhesive properties such as the secretion of a sandcastle marine worm, or a siloxane system such as that described in Wilson et al., Biomater Sci Polymer Ed. 2005; 16(4): 449-72, which is hereby incorporated by reference in its entirety. In general, it may be advantageous to use an adhesive  12  that is reactive to temperature, pH, salinity, water, or other biological factors in order to facilitate delivery of the implant  10  into the patient&#39;s body in a non- or lower- adhesive state. Upon delivery and/or deployment of the implant  110  to the target location, the adhesive strength of the adhesive  12  increases due to, at least in part, the reactivity of the adhesive  12  to a temperature, pH, salinity, water content, or other biological factor(s) present at the target location. 
         [0048]    The adhesive  12  can advantageously comprise a radiopaque material such as barium sulfate, tantalum powder, or iodine contrast solution so as to allow an operator to better visualize implant  110 . 
         [0049]    In one illustrative example, shown in  FIG. 6 , the implant  110  for treating an aneurysm has a primary shape formed from a coil having an outer diameter, OD, of approximately 0.012 inches and an inner diameter, ID, of approximately 0.008 inches and a secondary shape formed by further winding or manipulating the primary shape. The lumen  122  is formed of a polymer tube made from, for example, a polyolefin elastomer having a 0.007 inch OD and a 0.005 inch ID that is threaded through the 0.008 inch ID of the primary shape or coil of the implant  110 . The lumen  122  has multiple holes of approximately 0.0001-0.001 inches in diameter formed therein. The implant  110  is then dipped into a salt solution and cured so that the salt at least partially blocks some of the holes  124  of the lumen  122 . A distal portion of the lumen  122  is then closed or sealed by employing a knot or bonding near a distal end  126  of the primary shape of the implant  110 . 
         [0050]    The adhesive  12 , for example, nBCA or sandcastle-worm secretion, is then injected into an open proximal end of the lumen  122  while the lumen  122  is maintained in an approximately vertical position, thereby, at least partially filling the lumen  122  with adhesive  12 . A proximal portion of the lumen  122  near a proximal end  128  of the primary shape of the implant  110  is tied or bonded such that the adhesive  12  is at least partially or temporarily sealed within the lumen  122  of the implant  110 . The above-described lumen  122  and manufacturing steps have the additional benefit of enhancing the stretch-resistance of the implant  110 . The proximal end  128  of the completed implant  110  is then attached to a distal portion of a delivery mechanism. 
         [0051]    Using the delivery mechanism, the implant  110  is then intravenously delivered into an aneurysm or other body cavity using components such as a microcatheter. Once in contact with blood, the salt coating of the implant  110  begins to wash away and/or dissolve, thereby opening the holes  124  in the lumen  122 , allowing blood to infiltrate into the lumen  122 , and allowing the adhesive  12  to diffuse or migrate from an interior of the lumen  122  to the exterior surface of the implant  110 . During this time, which may be from 1 to 60 minutes, if desired, the operator can reposition the implant  110  with in the target location. Once the adhesive  12  reaches the exterior surface of the implant  110 , the adhesive  12  will contact patient tissue, other implants, and/or both and adhere the implant  110  to the patient tissue, other implants, and/or both. Hence, the implant  110  will be held in the target location and the risk of migration of the implant  110  will be reduced. 
         [0052]    In another embodiment, with reference to  FIG. 7 , the adhesive  12  is pre-loaded, i.e. loaded prior to delivery to a target location within the patient, into one or more wells  222  formed into an exterior surface  216  of the implant  210 . The wells  222  are formed, for example, by machining, drilling, etching, or similar means. After formation of the wells  222 , the wells  222  are enclosed with a covering  230  having pores or holes  224 . Once the wells  222  have been covered by the cover  230 , the adhesive  12  is injected or otherwise placed within the wells  222 . 
         [0053]    The size or diameter of the pores or holes  224  of the covering  230  are selected so as to selectively control the diffusion rate of the adhesive  12  from the wells  222 . Hence, the time in which the adhesive  12  adheres the implant  210  to the tissue and/or to other implants controlled so as to allow an operator to deliver, deploy, and re-position the implant  210  at the target location prior to adhesion of the implant  210  to the tissue and/or to other implants. The diffusion rate may alternatively or additionally, be controlled by treating an exterior surface of the covering  230  with a dissolvable substance such as salt. In order for the adhesive  12  to diffuse or migrate from the interior of the covering  230 , the dissolvable substance is first dissolved from the surface to the covering  230  by patient fluid, such as blood. 
         [0054]    The covering  230  is formed, for example, of a polymer such as a UV curable polymer and pores or holes  224  are formed therein as previously described. Alternatively, the covering  230  is formed of, for example, a polyolefin or ethylene-octene copolymer extruded under conditions resulting in the formation of micropores  224  within the extrusion. Alternatively, the covering  230  is formed from a polyamide that has micro-holes  224  cut therein by an excimer laser or other cutting technique. Alternatively, the covering  230  is formed from a polymer such as a polyolefin, Teflon, polyamide, PEEK, PET, or the like with holes  224  cut with an appropriately sized needle or drill. 
         [0055]    The adhesive  12  employed in the implant  210  is, for example, an adhesive material such as n-butyl cyanoacrylate (nBCA), a protein with adhesive properties such as the secretion of a sandcastle marine worm, or a siloxane system such as that described in Wilson et al., Biomater Sci Polymer Ed. 2005; 16(4): 449-72, which is hereby incorporated by reference in its entirety. In general, it may be advantageous to use an adhesive  12  that is reactive to temperature, pH, salinity, water, or other biological factors in order to facilitate delivery of the implant  210  into the patient&#39;s body in a non- or lower-adhesive state. Upon delivery and/or deployment of the implant  210  to the target location, the adhesive strength of the adhesive  12  increases due, at least in part, to the reactivity of the adhesive  12  to a temperature, pH, salinity, water content, or other biological factor(s) present at the target location. 
         [0056]    The adhesive can advantageously comprise a radiopaque material such as barium sulfate, tantalum powder, or iodine contrast solution so as to allow an operator to better visualize implant  210 . 
         [0057]    In one illustrative example, the implant  210  employs wells  222 , such as those disclosed in U.S. Pat. No. 7,208,011 to Shanley which is hereby incorporated by reference in its entirety. The wells  222  are filled with adhesive such as nBCA or sandcastle-worm adhesive and covered or sealed with the cover  230  formed of either a biodegradable polymer as described by Shanley or the permeable cover  230  previously disclosed that need not be biodegradable. Advantageously, the holes  224  are sealed with a material such as salt or sugar that quickly dissolves in a matter of a few minutes and/or that would allow relatively quick diffusion to ensure reliable adhesion of the implant  210  to the tissue. After delivery, the seal degrades and allows the adhesive  12  to diffuse to the surface of the implant  210  so as to adhere the implant  210  to patient tissue, other implants, and/or both. 
         [0058]    The operation and method for delivery and deployment of the implant  210  is otherwise as previously described with respect to implant  110 . 
         [0059]    With reference to  FIGS. 8-12 , in another embodiment of the present invention, an implant employs an adhesive that is delivered through a portion of the implant, for example through one or more lumens or cavities formed within the implant, after delivery and deployment of the implant at a target location within a patient. In order to deliver the adhesive to the implant, after delivery and deployment of the implant at a target location, the implant is partially integrated with a portion of a delivery system so as to form a delivery passage or lumen for flow of the adhesive. The one or more lumens or cavities of the implant are semi-permeable to an exterior surface of the implant such that, upon delivery of the adhesive to the implant at the target location, the adhesive within the one or more lumens or cavities will diffuse or migrate to the exterior surface of the implant. Once at the surface, the adhesive will adhere the implant to the patient&#39;s tissue, to other implants, and/or both, and thereby assist in securing the implant at the target location. The present embodiment allows an operator to deliver and re-position as needed and introduce the adhesive  12  only when the operator desires. 
         [0060]    More particularly, with reference to  FIG. 8 , in certain embodiments of the present invention, a lumen  322  extends through at least a portion of an implant  310  and through at least a portion of a delivery system  342  to an injection port  340 . The lumen  322  may be formed of a contiguous tube or may be formed of a series of interconnected tubes with or without differing mechanical properties. Such systems are described in U.S. Pat. Nos. 6,689,141 and 6,607,538, and U.S. Publication Nos. 2002/0188311 and US2004/0204701, all of which are hereby incorporated by reference in their entirety. At least a portion of the lumen  322  within the implant  310  has pores or holes  324  formed therein. The size or diameter of the pores or holes  324  of the lumen  322  is selected so as to selectively control the diffusion or migration of the adhesive  12  from the lumen  322 . The previously described step of salt-treating the surface of the lumens  110  and  210  may not be necessary since no adhesive  12  is present in the lumen at the time of delivery and deployment of the implant  310 . 
         [0061]    The lumen  322  is formed from a polyamide that has micro-holes cut therein by an excimer laser or other cutting technique. Alternatively, the lumen  322  is formed from a polymer such as a polyolefin, Teflon, polyamide, PEEK, PET, or the like with holes cut with an appropriately sized needle or drill. 
         [0062]    The adhesive  12  employed in the implant  310  is, for example, an adhesive material such as n-butyl cyanoacrylate (nBCA), a protein with adhesive properties such as the secretion of a sandcastle marine worm, or a siloxane system such as that described in Wilson et al., Biomater Sci Polymer Ed. 2005; 16(4): 449-72, which is hereby incorporated by reference in its entirety. In general, it may be advantageous to use an adhesive  12  that is reactive to temperature, pH, salinity, water, or other biological factors in order to facilitate delivery of the implant  310  into the patient&#39;s body in a non-or lower-adhesive state. Upon delivery and/or deployment of the implant  310  to the target location, the adhesive strength of the adhesive  12  increases due to, at least in part, the reactivity of the adhesive  12  to a temperature, pH, salinity, water content, or other biological factor(s) present at the target location. 
         [0063]    The adhesive  12  can advantageously comprise a radiopaque material such as barium sulfate, tantalum powder, or iodine contrast solution so as to allow an operator to visualize the adhesive as it is delivered through the delivery system  342 . 
         [0064]    Prior to use, the lumen  322  may be flushed of air by, for example, injecting saline solution through the injection port  340 . The operator will then deliver and reposition the implant  310  until the desired placement is achieved. Prior to detaching the implant  310  from the delivery system  342 , the adhesive  12  is injected through the injection port  340 . Injection of the adhesive  12  displaces the saline solution within the lumen  322 . The adhesive is pushed or wick out of the holes  324  in the lumen  322  and to the surface of the implant  310 . Once the adhesive  12  reaches the surface of the implant  310 , the adhesive  12  will contact patient tissue, other implants, and/or both and adhere the implant  310  to the patient tissue, other implants, and/or both. Hence, the implant  310  will be held in the target location and the risk of migration of the implant  310  will be reduced. 
         [0065]    After adhesion of the implant  310  to the patient tissue, other implants, and/or both, the implant  310  is detached from the delivery system  342  and the portion of the lumen  322  associated with the implant  310  is dissociated from the portion of the lumen  322  associated with the delivery system  342 . In order to facilitate detachment of the implant  310  from the delivery system  342 , as shown in  FIG. 9 , in certain embodiments of the present invention, a heater  344  is positioned near the lumen  322 , for example interior of the lumen  322 , at a location near a proximal end  328  of the implant  310 . Activation of the heater  344  by the operator severs to sever the lumen  322  and thereby detaches the implant  310  from the delivery system  342 . Similar detachment systems are described in U.S. Pat. No. 8,182,506 and U.S. Publication Nos. 2006/0200192 and US2006/052815, all of which are hereby incorporated by reference in their entirety. 
         [0066]    In another embodiment, with reference to  FIGS. 10 and 11 , an implant  410  having a multiple flow channel structure  450 , such as a honeycomb-like structure, is employed. A proximal portion  428  of the implant  410  is connected to a lumen  448  at a distal portion  446  of a delivery system  442 . The lumen  448  extend proximally within the delivery system  442  to an injection port  440 , as described previously with respect to the delivery system  342 . Adhesive  12  is injected into lumen  448  through the injection port  440 , enters an interior volume of the implant  410  and disperses or flows through the complex system of flow channel structure  450  to an exterior surface of the implant  410 . 
         [0067]    The implant  410  is formed by employing three-dimensional printing techniques. For example, the implant  410  may be formed by vapor deposition or by sintering a powdered metal or plastic over a dissolvable form. The dissolvable form is, for example, shaped in the form of a tubular stent, coil, frame, or similar implantable device formed of a polymer, salt, and/or wax. After vapor deposition or sintering of the powdered metal or plastic over the dissolvable form, the dissolvable form is dissolved with a solvent, water, and/or by heating leaving behind the implant  410  having a structure at least partially complementary to the dissolvable form that comprises the complex flow channel structure  450  spanning from an interior surface to an exterior surface of the implant  410 .  FIG. 10  shows a magnified view of the flow channel structure  450  of the implant  410 . 
         [0068]    The lumen  448  is formed, for example, of a polyamide, polyolefin, Teflon, polyamide, PEEK, PET, or the like. 
         [0069]    The adhesive  12  employed in the implant  410  is, for example, an adhesive material such as n-butyl cyanoacrylate (nBCA), a protein with adhesive properties such as the secretion of a sandcastle marine worm, or a siloxane system such as that described in Wilson et al., Biomater Sci Polymer Ed. 2005; 16(4): 449-72, which is hereby incorporated by reference in its entirety. In general, it may be advantageous to use an adhesive  12  that is reactive to temperature, pH, salinity, water, or other biological factors in order to facilitate delivery of the implant  410  into the patient&#39;s body in a non- or lower- adhesive state. Upon delivery and/or deployment of the implant  410  to the target location, the adhesive strength of the adhesive  12  increases due to, at least in part, the reactivity of the adhesive  12  to a temperature, pH, salinity, water content, or other biological factor(s) present at the target location. 
         [0070]    The adhesive  12  can advantageously comprise a radiopaque material such as barium sulfate, tantalum powder, or iodine contrast solution so as to allow an operator to visualize the adhesive as it is delivered through the delivery system  442 . 
         [0071]    In operation, the implant  410  is delivered to the target location while attached to the delivery system  442 . The operator may reposition the implant  410  as needed until the desired location and configuration are achieved. The operator then inject the adhesive  12  into the injection port  440 ; through the lumen  448 ; through an interior volume of the implant  410 ; through the flow channels  450  and onto an exterior surface of the implant  410 . Once the adhesive  12  reaches the surface of the implant  410 , the adhesive  12  will contact patient tissue, other implants, and/or both and adhere the implant  410  to the patient tissue, other implants, and/or both. Hence, the implant  410  will be held in the target location and the risk of migration of the implant  410  will be reduced. 
         [0072]    After adhesion of the implant  410  to the patient tissue, other implants, and/or both, the implant  410  is detached from the delivery system  442 . Detachment may be facilitated as described above with respect to the implant  310 , e.g. by thermal detachment. 
         [0073]    In another embodiment of the present invention, as shown in  FIGS. 12-14 , an implant  510  employs an adhesive component in the form of adhesion promoting structural features  512 . The adhesion promoting structural features  512  employ non-chemical adhesive properties, such as van der Waals forces, to assist in adhering the implant  510  to patient tissue and/or other implants to assist in holding or maintaining the implant  510  at the target location and, thereby, decrease the risk of migration of the implant  510  away from the target location. Such features  512  are further described in U.S. Pat. No. 7,828,982 which is hereby incorporated by reference in its entirety. 
         [0074]    In certain embodiments, the structural features  512  are, for example, small protrusions  532  extending from an exterior surface  516  of the implant  512 , for example, extending from the exterior surface  516  of a strut  14  of the implant  512 .  FIG. 12  shows a cross-sectional view of a portion of the implant  510  having a strut  14  employing the protrusion  532  extending from the exterior surface  516 . At a distal end  534 , the protrusion  532  may, but need not necessarily, employ a tip  536  in order to increase the surface area of the protrusion  532  and, hence the surface area of the implant  510 . The tip  536  is, for example, shaped in the form of a sphere, as shown in  FIGS. 12 and 13 , a spatula or paddle, as shown in  FIG. 14 , or other regular or irregular shape. For the sake of clarity and by way of example,  FIGS. 13 and 14  show cross-sectional views of a single strut  14  of the implant  510  within a patient&#39;s vasculature  2 . The features  512 , i.e. the protrusions  532  and tips  536 , are formed, for example, of a metal, alloy, and/or polymer. 
         [0075]    The quantity and dispersion of the features  512  employed on the implant  512  are selected based upon the intended application of the implant  512 . For example, if the implant  512  is intended for implantation in a relatively high-flow region more features  512  are employed so as to increase the adhesion properties of the implant  512 . In contrast, relatively fewer features  512  are employed in a relatively low-flow region where the forces acting upon the implant  512  are relatively lower. 
         [0076]    As shown in  FIG. 12 , the features  512  may, but need not necessarily be, attached to the implant  512  at an angle {circle around (−)}. The angle {circle around (−)} is, for example, determined as an angle of incidence relative to a longitudinal axis  538  of the implant  512 . The angle {circle around (−)} may be in the range of 5 to 85 degrees, or 25 to 35 degrees. 
         [0077]    In certain embodiments, the features  512  attached to the exterior surface  516  of the implant  512  by, for example, laser welding or adhesive bonding. To increase the surface area of the top of the protrusion  532  or the feature  512 , a laser can be used to form the tip  536  at the distal end  534  of the protrusion  532 . Alternatively, an ultra-violet, UV, curable liquid polymer can be placed at the distal end  534  of the protrusion  532  which will then form the sphere-shaped tip  536  through surface tension and curing. 
         [0078]    In certain embodiments, for example, when the protrusion  532  is formed of a ductile material such as platinum or an elastomeric polymer such as an ethylene-octene copolymer, the tip  536  can be mechanically rolled or flattened to form a spatula- or paddle-shaped surface. 
         [0079]    In certain embodiments, the features  512  are formed on the surface of the implant  512  by a molding or casting process. For example, the implant  512  is placed in a mold having the features  512  formed therein. A molten metal such as platinum is poured into the mold and hardens as it cools. The mold, for example, could contain features that shape the tips  536  of the protrusions  532 , or the tip  536  features could be created by a secondary process as previously described. Alternatively, the implant  512  is placed in the mold and a liquid polymer, for example, a polyimide, dissolved in a solvent or a UV curable polymer, for example, Loctite  349 , is poured into the mold and cured by heat to, evaporate the solvent, or UV light. In the present embodiments, the molded features  512  would attach or hold onto the implant  512  either through friction; chemical bonding, if the materials were compatible; or by a secondary process such as laser or resistance welding. Other bonding methods such as, for example, those described in U.S. Pat. No. 7,828,982 may also be employed. 
         [0080]    In one illustrative example of the present invention, the implant  512  is a coil intended for to treatment of a neurovascular aneurysm. Other devices to treat larger aneurysms or smaller devices to occlude, for example fallopian tubes or small aneurysms are possible by re-scaling this embodiment. A 0.002 inch platinum alloy wire is wound into a primary coil having a 0.012 inch outer diameter and a 0.008 inch inner diameter. The coil is then wound into a secondary shapes such as a helix or other complex three-dimensional shape, such as a sphere, helix, cage, box, or frames into which other coils can be deployed, as described in U.S. Pat. No. 8,066,036 and U.S. Publication No. US201210041464 which are hereby incorporated by reference in their entirety. For example, the coil can be wound into a secondary shape nominally 6 millimeters in diameter and 25 centimeters in length. 
         [0081]    Platinum wires 0.0005-0.004 inches in diameter are cut to lengths 0.001-0.04 inches. More particularly, 0.0002 inch diameter platinum wire is cut in to approximately 0.001 inch lengths. A laser is then used to form a ball-shaped tip  536  of approximately 0.0003 inches in diameter on the end of each platinum wire lengths or protrusions  532 . Each ball-tipped protrusion  532  is then laser welded to an exterior surface  516  of the coil at an angle of incidence {circle around (−)} of 25 to 35 degrees relative to the longitudinal axis  538  of the coil or implant  512 . The protrusions  532  are mounted at 120 degree increments around the longitudinal axis  538  of the coil implant  512  at 1 millimeter increments along the length of the coil implant  512 ; yielding approximately 750 features  512  on the implant  510 . 
         [0082]    The coil implant  510  is then attached to a delivery mechanism and delivered through a conventional microcatheter to the target location within the patient. The coil implant  510  can then be repositioned multiple times in, for example, a wide necked aneurysm. The coil implant  510  is detached once the desired deployment configuration is achieved. With prior art implants, there would be a high risk that an implant might migrate into the parent vessel and would, for example, need to be held in place by a stent. However, according to the present invention, the van der Waals forces between the aneurysm wall and the features  512  or the implant  510  will tend to hold the coil implant  510  in place and reduce the risk of migration without using a stent. 
         [0083]    According to one embodiment of the present invention, the implants  10 ,  110 ,  210 ,  310 ,  410 , and  510  may employ a combination of the above-described chemical adhesives  12  and the adhesion promoting structural features  512  to achieve the desired adhesive properties. 
         [0084]    Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof.