Low profile balloon catheter and method for making same

Claim 1

A non-distensible balloon adapted to be disposed circumferentially on a tube having an elongate axis, and adapted to be rolled on the tube to achieve a low profile, the balloon comprising: an end wall disposed in an end region of the balloon and in a fixed circumferential relationship with the tube; a central wall disposed in a central region of the balloon and in a displaced relationship with the tube when the balloon is inflated; a transition wall extending from the end wall to the central wall of the balloon, the transition wall defining; a height transition region wherein the transition wall extends from a first radius at the end wall to a second radius at the central wall, the height transition region having a first axial length, and a thickness transition region wherein the transition wall varies from a maximum thickness to a minimum thickness, the thickness transition region having a second axial length less than the first axial length; first portions of the balloon disposed in the transition wall and having a thickness t 1 , an inside radius r 1 , and an outside radius R 1 ; and second portions of the balloon disposed in one of the end wall, central wall and the transition wall, and having a thickness t 2 , an inside radius r 2 and an outside radius R 2 ; wherein the thickness t 1 of the first portions of the balloon is characterized by the following formula: ##EQU3##