High compliance, high strength catheter balloons useful for treatment of gastrointestinal lesions

Abstract

Balloon especially useful for dilatation of gastrointestinal lesions have a burst pressure of at least 9 atmospheres, a diameter at 3 atmospheres of about 5 mm or more, and an average compliance over the range of from 3 atmospheres to burst of at least 3% per atmosphere. Such balloons and balloons having other combinations of burst strength, compliance and diameter may be prepared by a method wherein a tubing of a thermoplastic polymer material is radially expanded under a first elevated pressure at an elevated temperature to form the balloon at a first diameter and then annealing the balloon at a second elevated temperature and a second pressure less than the first elevated pressure for a time sufficient to shrink the formed balloon to a second diameter less than the first diameter. The thermoplastic polymer material may be a block copolymer material. Catheters bearing balloons prepared by this method have low withdrawal force requirements, especially catheters used in through-the-scope applications.

1 - 34 . (canceled)  
     
     
         35 . A balloon for a medical device made by a method wherein a tubing of a thermoplastic polymer material is radially expanded under a first elevated pressure at an elevated temperature to form the balloon at a first diameter, the thermoplastic polymer material being a block copolymer material and the method including the further step of annealing the balloon at a second elevated temperature less than the first elevated temperature and a second pressure less than the first elevated pressure for a time sufficient to shrink the formed balloon to a second diameter less than the first diameter, and wherein said annealing step occurs prior to sterilization of the medical device.  
     
     
         36 . A balloon as in  claim 35  having an operating pressure to which the balloon may be safely inflated without bursting of at least 12 atmospheres, a diameter at 3 atmospheres of from about 1.5 to about 6.0 mm and a diameter growth of at least 1.0 mm over the range of 3-12 atm.  
     
     
         37 . A balloon as in  claim 35  having an operating pressure to which the balloon may be safely inflated without bursting of at least 10 atmospheres, a diameter at 3 atmospheres of from about 6 to about 12 mm and a diameter growth of at least 2 mm over the range of 3-10 atm.  
     
     
         38 . A balloon as in  claim 35  having an operating pressure to which the balloon may be safely inflated without bursting of at least 9 atmospheres, a diameter at 3 atmospheres of from about 12 to about 30 mm and a diameter growth of at least 3 mm over the range of 3-9 atm.  
     
     
         39 . A balloon as in  claim 38  wherein said diameter growth is at least 4 mm.  
     
     
         40 . A balloon as in  claim 35  that has been sterilized subsequent to said annealing step.  
     
     
         41 . A balloon for a medical device having a diameter at 3 atmospheres inflation pressure of at least 5 mm, a burst pressure of at least 9 atmospheres, and a growth rate in the range of 3 atmospheres to burst of at least 4% per atmosphere.  
     
     
         42 . A balloon as in  claim 41  wherein said diameter at 3 atmospheres is from about 6 to about 12 mm, the balloon further characterized by an operating pressure to which the balloon may be safely inflated without bursting of at least 10 atmospheres and a diameter growth of at least 2 mm over the range of 3-10 atmospheres.  
     
     
         43 . A balloon as in  claim 41  wherein said diameter at 3 atmospheres is at least 12 mm and said balloon has a diameter growth of at least 3 mm over the range of 3-9 atmospheres.  
     
     
         44 . A balloon as in  claim 43  wherein said diameter growth over the range of 3-9 atmospheres is at least 4 mm.  
     
     
         45 . A balloon as in  claim 43  wherein said diameter at 3 atmospheres is in the range of about 12 to about 18 mm.  
     
     
         46 . A balloon is in  claim 41  made from thermoplastic polymer material selected from the group consisting of block copolymers, thermoplastic elastomers, polymer blends, random copolymers of rigid and flexible monomers, polyurethanes which have rigid and flexible portions, polyketones, polysulfides and polyamide homopolymers and copolymers.  
     
     
         47 . A balloon as in  claim 41  formed from at least two concentric layers of different thermoplastic polymers.  
     
     
         48 . A balloon as in  claim 41  having a double wall thickness of about 0.00457 inches or less.  
     
     
         49 . A balloon as in  claim 41  wherein said diameter at 3 atmospheres is about in the range of 6-30 mm.  
     
     
         50 . A balloon as in  claim 41  wherein said diameter at 3 atmospheres is about 12 mm or more.  
     
     
         51 . A catheter for treatment of a gastrointestional lesion comprising a balloon as in  claim 41 .  
     
     
         52 . A medical device balloon formed by a method comprising: 
 radially expanding tubing of thermoplastic polymer material under elevated blowing pressure greater than 50 psi at an elevated blowing temperature to form the balloon to have a first diameter at 3 atm inflation pressure,    annealing the formed balloon prior to sterilization of the medical device at an elevated annealing temperature less than or equal to the blowing temperature, and at an annealing pressure which in the range of 0-20 psi, for a time sufficient to shrink the formed balloon to have a second diameter at 3 atm inflation pressure which is less than 90% of the first diameter, and then    pressurizing the balloon in a fixed diameter form, said fixed diameter being greater than said second diameter but no more than 90% of said first diameter, at a pressure above the annealing pressure but no more than 50 psi and a temperature not less than said annealing temperature and not greater than said blowing temperature for a time to provide the balloon with a final diameter at 3 atm inflation pressure which is greater than said second diameter but not more than 90% of said first diameter.    
     
     
         53 . A medical device balloon as in  claim 51  wherein said final diameter is 85% or less of said first diameter.  
     
     
         54 . A medical device balloon as in  claim 51  wherein said final diameter is 65-75% of said first diameter.  
     
     
         55 . A medical device balloon as in  claim 51  wherein the thermoplastic polymer material is a block copolymer, a thermoplastic elastomer, a polymer blend, a random copolymer of rigid and flexible monomers, polyurethanes which have rigid and flexible portions, polyketones, polysulfides or a polyamide homopolymer or copolymer.