Methods of manufacturing nested balloons utilizing pressurized constrained annealing

Abstract

A nested balloon is provided where each balloon is formed from tubing that optimizes the inner wall stretch thus providing maximum balloon strength. The high pressure, nested balloon is provided with layers that allow for slipping, such that the balloon has a very high pressure rating and toughness, yet excellent folding characteristics. Methods for producing such nested balloons using existing balloon forming equipment are also provided. The nested balloons can have layers with low-friction surfaces. The nested balloons are preferably manufactured using a variety of methods, including pressurized constrained annealing.

Description

RELATED APPLICATIONS[0001]This application claims priority under 35 U.S.C. §119(e) as a nonprovisional of U.S. Prov. Patent Application No. 62 / 069,303 filed Oct. 27, 2014. The entire disclosure of the foregoing priority application is hereby incorporated by reference herein for all purposes.[0002]The entire disclosure of U.S. patent application Ser. No. 11 / 611,748 filed Dec. 15, 2006, (now U.S. Pat. No. 7,942,847 issued May 17, 2011), is also incorporated by reference its entirety.BACKGROUND[0003]1. Field[0004]Embodiments relate generally to balloon catheters and methods for making balloon catheters for medical applications. In particular, embodiments relate to a nested balloon having at least two balloons having different properties. The balloons may have multiple layers such as a layer comprising a low coefficient of friction.[0005]2. Description of the Related Art[0006]An increasing number of surgical procedures involve percutaneously inserted devices that employ an inflatable th...

AI Technical Summary

Benefits of technology

The disclosed patent describes commercial high pressure nested balloon catheters that have multiple balloons with optimized stretch properties for maximum strength. These nested balloons have very high pressure ratings, excellent folding characteristics, and increased flexibility compared to single balloons of the same size. The flexibility is increased by about 25% to 75% greater than a single balloon with the double wall thickness. The inner layer of one of the balloons can have lower strength and hardness. The nested balloons can also have a low coefficient of friction to facilitate sliding between adjacent balloons. Additionally, the patent describes how individual balloons can be nested after altering their orientation to make them thinner, and already nested balloons can be treated as a single balloon by increasing the number of balloons.

Problems solved by technology

Additional, higher pressures may be needed to affect the treatment.

Radial stress can lead to axial bursting of the balloon parallel to its longitudinal axis.

Axial stress can lead to radial bursting of the balloon somewhere along the balloon's circumference (e.g., complete fracture of the balloon).

However, in the presence of balloon deformities, a balloon may burst radially.

Such a radial bursting could disadvantageously leave separated sections of the balloon inside the patient after the catheter is removed.

Consequently, a balloon having an increased balloon wall thickness might have limited access to certain areas in a patient due to the balloon's increased size.

This added wall stiffness impairs one's ability to tightly wrap the balloon around the catheter shaft, which is necessary to limit the size of the balloon's cross-sectional area.

If the balloon is bent too much beyond its stiffness, undesirable deformities may result.

These methods are often not entirely successful in creating a more desirable balloon with improved mechanical characteristics.

For the reasons described below, these prior art multi-layer balloons also have serious deficiencies.

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