A tubular support member located in a distal portion of an elongate flexible medical device is provided with a plurality of wall openings, e.g., axially-spaced, substantially transverse slots, formed therein to thereby increase a flexibility of the support member. A layer of sealing material overlays an outer surface the support member so as to provide a sealed portion of the support member including the wall openings, the sealing material having respective flexible invaginations formed therein overlaying the wall openings in the support member so that the sealing material does not substantially impede flexibility of the support member.