Adjustable nonimplantable electrical stimulators for correction of urinary incontinence.

Investigations of functional electrical stimulation (FES) of the closing muscles in the lower urinary tract using nonimplantable electrical stimulators have reached the final stage. The optimal stimuli parameters were chosen on the basis of neurophysiological studies of the urinary tract and urodynamic measurements of mechanical response to electrical stimulation. According to these findings, two electronic systems for FES have been developed. An adjustable system for stimulation of the urethral closing mechanism using vaginal or anal plugs. The external unit of the stimulator contains a generator producing square-wave pulses. The vaginal and anal plugs are from Vitalograph Ltd, and Cardiac Recorders Ltd., commercial tipes redesigned to suit our needs. Frequency and duration of the pulses can be individually adjusted for each patient. An automatic integrated adjustable system for stimulation of the urethral closing mechanism built into a vaginal plug. This stimulator is based on completely new design principles. It has the form of a cylinder with hemispherical ends. Both the electronic unit and battery supply are located within. The system is completely automatic and is started by placing the stimulator in the vagina. Both systems mentioned were constructed for curing stress incontinence, post-operative incontinence, enuresis and in some cases for use in incontinent paraplegics. Clinical evaluation has given satisfactory results for both types of stimulators in the above-mentioned patients. They are simple to use and instructions can be given in an urologist's prescription. Permanent or intermittent application is possible.