Catheter with non-adhering balloon

Claim 1

A catheter, comprising: an elongated shaft having a main lumen, an inflation lumen extending along the shaft, and an outer surface; an annular sleeve of elastic material joined to the shaft in spaced first and second circumferential zones defining a cavity intermediate said sleeve and shaft, said inflation lumen communicating with the cavity to inflate said sleeve, and said sleeve having an inner surface facing toward a region of said outer surface of the shaft underlying the sleeve, with said surface region of the shaft being substantially smooth; and said sleeve having a plurality of inner spaced circumferential ridges having inner surfaces facing toward the outer surface region of the shaft, said ridges defining a plurality of circumferential recesses having surfaces intermediate the ridge inner surfaces, with the inner surfaces of said ridges contacting the outer surface region of the shaft until use of the catheter, and said ridges having a sufficient width relative to the width of the recesses to prevent contact of the recess surfaces with the outer surface region of the shaft when the ridge inner surfaces contact the outer surface region of the shaft.