Variable stiffness shaft

摘要

Medical devices may include structure or provision that permit a physician or other health care professional to adjust particular parameters such as flexibility, stiffness and compressive strength of at least a portion of the medical device. In some instances, the medical device may be adjusted prior to inserting the medical device into a patient. In some cases, the medical device may be adjusted while in use within the patient.

主权项

1. A medical device comprising:
a hypotube comprising a plurality of slots passing transversely through a longitudinal sidewall of the hypotube, each slot of the plurality of slots comprising a first wall and an opposing second wall defining a space between the first wall and the opposing second wall; an electroactive polymer sleeve disposed on an exterior wall of the hypotube, said electroactive polymer sleeve having a first configuration in which the electroactive polymer sleeve does not occupy the space between the first wall and the opposing second wall and a second configuration in which the electroactive polymer sleeve at least partially occupies the space between the first wall and the opposing second wall, which electroactive polymer when subjected to a potential difference applied between two electrodes causes available ions to move into the electroactive polymer to swell the electroactive polymer such that the electroactive polymer sleeve changes from the first configuration to the second configuration thereby changing a compressive strength of the hypotube; wherein the hypotube is one of the two electrodes.