Covered embolic coils

Abstract

An embolic implant for treating aneurysms or other vascular disorders may include a cover component of unitary construction that is disposed about the exterior of a microcoil such that it does not extend into a lumen formed by the coil. The cover can enhance packing volume and density per unit length of coil, and can prevent blood flow and cause blood clotting while not risking rupture of the vascular disorder. The cover may also provide a platform for the application of multiple treatments and/or therapies including, for example, functionalized and/or bioactive coatings, drug coatings, gene therapy, thrombogenicity control coatings, and surface modifications, while preserving key coil performance attributes.

What is claimed is: 
     
         1 .- 30 . (canceled) 
     
     
         31 . A method of manufacturing an implant for use in treating a vascular disorder, the method comprising the steps of:
 obtaining an embolic coil forming a lumen;   forming a cover of unitary construction by creating a pattern in a sheet of unitary construction using a subtractive manufacturing technique; and   helically winding the cover about an exterior of the embolic coil, such that the cover does not extend into the lumen formed by the embolic coil.   
     
     
         32 . The method of  claim 31 , wherein the sheet comprises a metallic foil. 
     
     
         33 . The method of  claim 32 , wherein the metallic foil comprises a material selected from the group consisting of nitinol, tantalum, tungsten, platinum, platinum iridium, cobalt chrome, magnesium, iron, stainless steel, and combinations and alloys thereof. 
     
     
         34 . The method of  claim 31 , wherein the sheet comprises a thickness in a range from about 5 microns to about 250 microns. 
     
     
         35 . The method of  claim 31 , wherein the subtractive manufacturing technique is selected from the group consisting of a laser technique, a mechanical technique, a wet chemical technique, an electrochemical masking technique, a maskless electrochemical technique, etching, milling, photochemical machining, and photoelectrochemical machining. 
     
     
         36 . (canceled) 
     
     
         37 . The method of  claim 31 , wherein the step of disposing the cover about the exterior of the embolic coil comprises shaping the cover into a tubular geometry and placing the cover over the embolic coil. 
     
     
         38 . The method of  claim 37 , wherein the step of shaping the cover into the tubular geometry comprises heat setting. 
     
     
         39 . The method of  claim 31  further comprising:
 disposing the cover and the embolic coil in a holding tube that maintains the cover in a constrained configuration about the exterior of the embolic coil; 
 attaching the cover to the embolic coil at at least one end; and 
 pushing the attached cover and embolic coil into a second tube that maintains the constrained configuration of the cover. 
 
     
     
         40 . The method of  claim 39 , wherein the step of attaching the cover to the embolic coil comprises using an attachment technique selected from the group consisting of laser welding, resistance welding, applying a medical adhesive, applying continual coatings, and employing a mechanical interference fit. 
     
     
         41 . The method of  claim 39 , further comprising attaching the second tube to a delivery pusher. 
     
     
         42 . The method of  claim 31 , wherein the cover comprises a shape memory material.