Detachable Coil Incorporating Stretch Resistance

Abstract

An implantable embolic device having a stretch-resistant member passing therethrough that also serves as a tether for connecting the device to a delivery system. The stretch-resistant member is attached at a proximal and distal end of the device and extends proximally to the delivery device. The proximal attachment point serves to isolate a distal, stretch resisting segment of the member from axial tension placed on a proximal, connecting section of the member. Thus, the portion of the stretch-resistant member being used to connect the embolic device to a delivery device may be placed under tension without placing tension or distorting the implant.

1 . A detachable implant delivery system comprising:
 a delivery device having a distal end and a heater proximate said distal end;   an implant attached to said distal end of said delivery device, wherein said implant defines a lumen;   a stretch-resistant member connecting said delivery device and said implant, said stretch-resistant member passing through said lumen and attached to at least two locations on said implant, said stretch-resistant member continuing proximally in operable proximity to said heater, such that upon activation of said heater, said stretch-resistant member breaks, releasing said implant.   
   
   
       2 . The detachable implant delivery system of  claim 1  wherein said stretch-resistant member is attached to said implant with a knot. 
   
   
       3 . The detachable implant delivery system of  claim 1  wherein said stretch-resistant member is attached to said implant with adhesive bonding. 
   
   
       4 . The detachable implant delivery system of  claim 1  wherein said stretch-resistant member comprises a material selected from the group consisting of polyolefin, polyethylene, polyolefin elastomers, ethylene-octene copolymer, biodegradable materials, PGLA, hydrogel, acrylamide, PEG, PET, nylon, amide-based polymers, block copolymers, PEBAX, polypropylene. 
   
   
       5 . The detachable implant delivery system of  claim 1  wherein said stretch-resistant member is under tension proximal of at least one attachment point. 
   
   
       6 . The detachable implant delivery system of  claim 1  wherein tension in said stretch-resistant member between said at least two implant attachment points is independent of tension in said stretch-resistant member proximal to the more proximal of said at least two attachment points. 
   
   
       7 . The detachable implant delivery system of  claim 1  wherein said implant comprises a coil. 
   
   
       8 . The detachable implant delivery system of  claim 7  wherein said stretch-resistant member comprises a tether tied to said coil. 
   
   
       9 . The detachable implant delivery system of  claim 8  wherein said tether is wound around said coil at the more proximal of said at least two attachment points, thereby isolating tension in said tether proximal of said more proximal attachment point from a portion of said tether that extends between said at least two attachment points. 
   
   
       10 . The detachable implant delivery system of  claim 1  wherein said implant device comprises a hydrogel material. 
   
   
       11 . A method of delivering an implantable coil comprising:
 providing a stretch-resistant member through a lumen of said coil and attaching said member proximate a distal end of said coil;   routing said tether in operable proximity to a tether-breaking device usable to release said implant;   placing tension on said tether;   isolating said tension from said coil;   placing said coil in a designated location in a patient;   activating said tether-breaking device.   
   
   
       12 . The method of  claim 11  wherein isolating said tension from said coil comprises attaching said tether at a second location on said coil. 
   
   
       13 . The method of  claim 12  wherein attaching said tether at said second location on said coil comprises wrapping said tether around said coil. 
   
   
       14 . The method of  claim 11  wherein routing said tether in operable proximity to a tether-breaking device usable to release said implant comprises routing said tether in operably proximity to a heater. 
   
   
       15 . A detachable implant comprising:
 a flexible distal member;   a tether usable to connect said flexible distal portion to a delivery device, said tether including:
 a first section extending through said flexible distal member; and, 
 a second section extending proximally from said first section; 
   wherein said first section is not under the same tension as the second section and said first section is stretch-resistant,   wherein said second section is attached to a proximal attachment point on said flexible distal member such that said first section is substantially isolated from axial tension placed on said second section.   
   
   
       16 . The detachable implant of  claim 15  wherein said first section is attached to said flexible distal member with a knot. 
   
   
       17 . The detachable implant of  claim 15  wherein said first section is attached to said flexible distal member with adhesive bonding. 
   
   
       18 . The detachable implant of  claim 15  wherein said tether comprises a material selected from the group consisting of polyolefin, polyethylene, polyolefin elastomers, ethylene-octene copolymer, biodegradable materials, PGLA, hydrogel, acrylamide, PEG, PET, nylon, amide-based polymers, block copolymers, PEBAX, polypropylene. 
   
   
       19 . The detachable implant of  claim 15  wherein said flexible distal member comprises a coil. 
   
   
       20 . The detachable implant of  claim 19  wherein said tether is tied to said coil near a distal end and near a proximal end of said coil. 
   
   
       21 . The detachable implant of  claim 15  wherein said detachable implant further comprises a hydrogel material. 
   
   
       22 . A detachable implant delivery system comprising:
 a delivery device having a distal end and a heater proximate said distal end;   an implant defining a lumen;   a stretch-resistant member both connecting said delivery device and said implant and preventing elongation of said implant, said stretch-resistant member attached to said implant such that said stretch-resistant member is under tension without altering a shape of said implant.   
   
   
       23 . The detachable implant delivery system of  claim 22  wherein said stretch-resistant member prevents elongation by connecting a distal end of said implant to a proximal end of said implant. 
   
   
       24 . The detachable implant delivery system of  claim 23  wherein said tension is isolated from between said distal end of said implant and said proximal end of said implant. 
   
   
       25 . The detachable implant delivery system of  claim 22  wherein said stretch-resistant member comprises a material selected from the group consisting of polyolefin, polyethylene, polyolefin elastomers, ethylene-octene copolymer, biodegradable materials, PGLA, hydrogel, acrylamide, PEG, PET, nylon, amide-based polymers, block copolymers, PEBAX, polypropylene. 
   
   
       26 . The detachable implant delivery system of  claim 22  wherein said tension is isolated via an attachment point near a proximal end of said implant. 
   
   
       27 . The detachable implant delivery system of  claim 26  wherein said attachment point comprises said stretch-resistant member wrapped around a portion of said implant at least once. 
   
   
       28 . The detachable implant delivery system of  claim 26  wherein said attachment point comprises a knot tied with said stretch-resistant member around a portion of said implant. 
   
   
       29 . The detachable implant delivery system of  claim 22  wherein implant comprises a coil and said stretch-resistant member comprises a tether attached to said coil at least a proximal end of said coil. 
   
   
       30 . The detachable implant delivery system of  claim 29  wherein said tether is wound around said coil at a more proximal of at least two attachment points, thereby isolating tension in said tether proximal of said more proximal attachment point from a portion of said tether that extends between said at least two attachment points. 
   
   
       31 . The detachable implant delivery system of  claim 22  wherein said implant device comprises a hydrogel material.