A medical device such as a catheter is described having a stiff, preferably metallic, proximal tube. The distal portion of the proximal tube may have a plurality of perforations or slots formed therein to increase its flexibility. This provides a smooth transition between the relatively ...http://www.google.ca/patents/US5743876?utm_source=gb-gplus-sharePatent US5743876 - Catheter having shaft of varying stiffness
