THE DEVELOPMENT AND EVOLUTION OF ARTIFICIAL URETHRAL SPHINCTERS

The history and evolution of mechanical devices designed to achieve ur inary continence are reviewed. The following devices were studies: Fol ey clamp, Kaufman prosthesis, Giori, Summers and Rosen sphincters, Gru neberger and Cleveland Clinic magnetic designs, Craggs sphincter and t he AMS family of sphincters (AMS 721, AMS 761, AMS 742 (A, B, C), AMS 792, AMS 800). The design of active hydraulic devices is discussed in more detail. This review analyses the problems relating to the applica tion of pressure and the presence of foreign material around the ureth ra. 'Volume set' devices are universally unsuccessful and detrimental for urethral integrity as opposed to 'pressure set' hydraulic sphincte rs (e.g. AMS 800). The implications for the design of artificial impla nts are discussed.