Lead assembly with porous polyethylene cover

Abstract

This document discusses, among other things, a lead assembly including a porous polyethylene cover. In an example, the cover includes sections that have differing pore sizes. In an example, a section of the cover near a distal end portion of a lead assembly includes pores that are large enough to allow tissue ingrowth. In another example, a lead assembly includes two or more polyethylene covers having different porosities.

We claim: 
     
         1 . A method comprising:
 wrapping a porous polyethylene material around a portion of a lead assembly under tension such that adjacent portions of the porous polyethylene material form a spirally overlapping cover around the lead assembly;   controlling pore sizes in the porous polyethylene material by varying the tension during wrapping such that pore size in a first section of the porous polyethylene material is larger than pore size in a second section of the porous polyethylene material;   fusing the adjacent portions of the porous polyethylene material together by applying heat.   
     
     
         2 . The method of  claim 1 , wherein controlling the pore sizes further comprises applying a first tension in controlling pore sizes in the first section of the porous polyethylene material and applying a second tension in controlling pore sizes in the second section of the porous polyethylene material, the first tension being higher than the second tension. 
     
     
         3 . The method of  claim 2 , wherein controlling the pore sizes further comprises controlling pore size in the first section in the first piece of the polyethylene material to allow tissue ingrowth, and controlling pore size in the second section in the first piece of the polyethylene material having pores that inhibit tissue ingrowth. 
     
     
         4 . The method of  claim 1 , wherein fusing the first portion of the first piece of polyethylene material to the second portion of the first piece of polyethylene material comprises heating the polyethylene material to between 80 and 150 degrees. 
     
     
         5 . The method of  claim 4 , wherein fusing the adjacent portions of comprises heating the polyethylene material via a laser, infrared (IR) wand, heat gun, or oven. 
     
     
         6 . The method of  claim 1 , wherein wrapping the porous polyethylene material comprises wrapping the porous polyethylene material having a thickness between 0.0001 and 0.010 inches, and a width between 0.1 and 8 inches 
     
     
         7 . The method of  claim 1 , wherein controlling the pore sizes in the porous polyethylene comprises controlling pore sizes to be between 0.1 micron and 15 microns. 
     
     
         8 . The method of  claim 1 , further comprising wrapping a second piece of porous polyethylene material around the first recited porous polyethylene material, the second piece of porous polyethylene material having pores that are larger than the pore size in a second section of the porous polyethylene material. 
     
     
         9 . The method of  claim 8 , further comprising fusing the second piece of porous polyethylene material to the first recited porous polyethylene material by applying heat. 
     
     
         10 . A method comprising:
 wrapping a porous polyethylene material around a first portion of a lead assembly;   controlling pore sizes in the porous polyethylene material by laser drilling the porous polyethylene material; and   fusing a first portion of the porous polyethylene material to a second portion of the porous polyethylene material.   
     
     
         11 . The method of  claim 10 , wherein controlling differing pore sizes in the polyethylene material further comprises applying tension and adjusting the tension during wrapping. 
     
     
         12 . The method of  claim 11 , wherein controlling differing pore sizes in the polyethylene material further comprises concurrently applying tension and laser drilling the porous polyethylene material. 
     
     
         13 . The method of  claim 11 , wherein controlling differing pore sizes in the polyethylene material comprises sequentially applying tension and laser drilling the porous polyethylene material. 
     
     
         14 . The method of  claim 10 , wherein controlling differing pore sizes in the porous polyethylene material comprises laser drilling pores in a pattern. 
     
     
         15 . The method of  claim 10 , wherein controlling differing pore sizes further comprises providing pores in a first section and in a second section of the polyethylene material, and wherein the pores in the first section are larger than the pores in the second section of the polyethylene material. 
     
     
         16 . The method of  claim 15 , wherein controlling differing pore sizes further comprises providing a first section in the polyethylene material having pores that allow tissue ingrowth, and providing a second section in the polyethylene material having pores that inhibit tissue ingrowth. 
     
     
         17 . A method comprising:
 wrapping a porous polyethylene material around a first portion of a lead assembly and controlling pore sizes in the polyethylene material;   hydrophilicly treating at least a portion of the porous polyethylene; and   securing a first portion of the porous polyethylene material to a second portion of the porous polyethylene material.   
     
     
         18 . The method of  claim 17 , wherein hydrophilicly treating the portion of the porous polyethylene comprises wetting the portion of the porous polyethylene using a plasma technique. 
     
     
         19 . The method of  claim 17 , wherein hydrophilicly treating the portion of the porous polyethylene comprises using a chemical hydrophilic treatment that includes at least one of polyvinyl acetate (PV A) and polyethylene glycol (PEG). 
     
     
         20 . The method of  claim 17 , wherein hydrophilicly treating the portion of the porous polyethylene comprises using at least one of glycol, acrylic acid, allyl amine, isopropyl alcohol (IPA), ethanol, and methanol.