A new pressure-regulated artificial urinary sphincter (AUS) has been developed which overcomes many of the deficiencies of earlier devices. This implantable AUS comprises a circular occluder cuff and the means to inflate and deflate through a pressure-regulated valve. The device is made from medical-grade silicone rubber and filled with radio-opaque isotonic fluid. A few days before surgery the implant is coated on the outside with an antibiotic-loaded silicone rubber solution. Tests have shown that the regulated pressure was very easily adjusted in situ by injecting or withdrawing the hydraulic fluid through a hypodermic needle penetrating a self-sealing filling port. When set, the regulated pressure remained very stable. The mechanism by which cuff pressure was increased to overcome stress incontinence worked well. Of the five earlier devices (AUS Mk I) implanted, none has survived without mechanical failure. The two latest implants (Mk II), which were rigorously tested for defects before implantation, have been more successful.

Adolescent↗

PubMedDate not supplied

Emerging clinical applications of electrical stimulation: opportunities for restoration of function.

Emerging clinical application of electrical stimulation in three systems is reviewed. In the bladder, stimulation of sacral posterior roots reduces reflex incontinence and significantly improves bladder capacity. With the combination of anterior and posterior root stimulation, bladder control can be achieved without the need for rhizotomy. Preliminary research demonstrates that bladder contractions may also be generated by stimulation of the urethral sensory branch of the pudendal nerve, even after acute spinal cord transection, while inhibition of the bladder and control of urge incontinence can be achieved by stimulation of the whole pudendal nerve. Spinal cord stimulation can modulate the activity of the intrinsic cardiac nervous system involved in the regulation of regional cardiac function and significantly reduce the pain associated with angina pectoris. Finally in the area of upper airway disorders, functional electrical stimulation has great potential for increasing life support as well as for quality of life in chronic ailments, particularly obstructive sleep apnea and dysphagia.

Angina Pectoris↗