REMOVABLE NITINOL STENT FOR TEMPORARY RELIEF OF LOWER URINARY TRACT OBSTRUCTION

摘要

High-energy microwave hyperthermia, radio-frequency and laser therapies are common procedures for the treatment of Benign Prostatic Hyperplasia (BPH). For the relief of transient urethral obstruction following these procedures as well as situations such as complete retention associated with major medical illness, a prostate stent that is easily removable and can be used permanently or temporarily is highly desirable as an alternative to an indwelling bladder catheter. A thermally recoverable and removable Nitinol prostate stent has been developed for temporary placement to relieve the symptom. The stent is easily loaded onto the delivery catheter after sub-ambient cooling. Through transurethral implantation, the stent once deployed by removing the cover sheath regains its predetermined austenite shape of helical strip coil at body temperature. The strip coil design effectively minimizes tissue in-growth, thus facilitating later stent removal. The removal of the stent is easily accomplished after in situ cooling with iced saline lavage by gentle traction unraveling the coil through a catheter.