Development and Testing of a Manually Actuated Hydraulic Sphincter for the Control of Urinary Incontinence

This article covers the development and testing (in vitro and in vivo) of an implanted artificial sphincter for the control of urinary incontinence. The implant includes a cuff to be implanted around the urethra, and an actuator unit to activate and deactivate the cuff and to control the cuff pressure. The design overcomes some of the limitations of other such implants by providing easy adjustment of the nominal cuff pressure, an increase in cuff pressure in response to transient increases in peritoneal pressure, and an easier way for the patient to pressurize and depressurize the cuff. The original design concept is evaluated, and the evolution of the design as a result of in vivo testing in dogs is described, along with details on the value and difficulties of such testing.