Esophageal balloon catheter with asymmetrical balloon

Abstract

A balloon catheter for use with an endoscope may have a flexible shaft extending between a proximal and distal end, with a hub affixed to the proximal end, and a balloon that is longitudinally asymmetrical. A balloon may have a central or cylindrical working portion, flanked by proximal and distal tapering portions, which are in turn flanked by proximal and distal balloon legs, which are affixed to the catheter shaft. In more specific detail, a longitudinally asymmetrical balloon may have proximal and distal tapering portions that have a relatively steep and a relatively shallow tapering angle, respectively. An optional additional feature of such a balloon catheter is that the catheter shaft may have a high pull strength and low longitudinal elongation, by including some type of reinforcement.

Description

BACKGROUND AND SUMMARY OF THE INVENTION [0001] 1. Technical Background [0002] The present invention relates generally to medical devices, and more particularly to a balloon catheter for use with an endoscope. [0003] 2. Discussion [0004] There are many different kinds and types of balloon catheters, including for example angioplasty catheters, stent delivery system catheters, etc. [0005] By way of example, the present invention will be described in relation to an esophageal balloon catheter. However, it should be understood that the present invention relates to any balloon catheter having the features recited in any one of the following claims, and is not limited to any particular treatment such as esophageal use, or use with an endoscope, or the particular example embodiments described below. [0006] Balloon catheters often have a relatively flexible tubular shaft having a certain length, which defines one or more tubular passages or “lumens” extending through part or all of the cath...

AI Technical Summary

Benefits of technology

[0010] When a catheter has no guidewire lumen, but instead has a flexible wire or wire-like distal extension affixed to the catheter, it may be referred to as a “fixed wire” catheter. Whether a particular catheter has a guidewire lumen or has a fixed-wire design, the guidewire or fixed-wire is intended to allow the catheter to more easily select and steer along a desired path.

[0014] In the case of a balloon catheter for use with an endoscope, the balloon material may be translucent, to allow a physician to use the endoscope to look through the balloon material at the anatomy, so the physician can accurately position the balloon. In addition, the proximal tapering portion of a translucent balloon may have a relatively steep tapering angle, to enhance the clarity of the picture presented to the physician by the endoscope.

[0016] Accordingly, another possible feature of a balloon catheter may be a balloon having a distal tapering portion with a relatively shallow tapering angle, so as to facilitate retraction of the balloon catheter back into an endoscope. The resulting gradual change in distal balloon size may tend to cause the balloon material to more easily fold or pleat and reenter a passage defined by the endoscope, thus reducing retraction force.

[0017] Regarding high pull strength, it may be desirable to provide a catheter shaft of a balloon catheter with reinforcement, such as reinforcing braid or strand(s). The resulting stronger catheter shaft will thus exhibit low longitudinal elongation under stress. Accordingly, if retraction becomes difficult, such reinforcing element(s) will tend to resist elongation of the catheter shaft.

[0018] An optional additional feature may be one or more visual markers provided on the balloon material or in the balloon material itself. Such visual markers may assist a physician to accurately position the balloon. In the case where a balloon catheter is used with an endoscope, the marker may be viewed visually with the endoscope, by using the endoscopic lens to look through the balloon material of the proximal tapering portion. In other words, the physician's view is provided by an endoscope positioned proximal of the balloon, yet the physician can look through the translucent material of the balloon proximal tapering portion, and see the interior surface of a cylindrical working portion to visualize where the marker(s) is from the “inside.”

Problems solved by technology

During such retraction into an endoscope or guiding catheter, the balloon material of some balloon catheters may possibly “bunch up” toward the distal direction as the balloon catheter is withdrawn back into such a passage or lumen, which may make retraction difficult.

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