PD08-04\u2003BIO-ENGINEERING OF A NOVEL BLUETOOTH TELEMETRICALLY CONTROLLED ARTIFICIAL URINARY SPHINCTER

Abstract

INTRODUCTION AND OBJECTIVES: The artificial urinary sphincter (AUS) for post-prostatectomy stress urinary incontinence (PPI) has become the gold standard treatment. Precision Medical Devices (PMD) has developed a new AUS. The Politano-Sayet-Sutherland Flow Control Device (PSS-FCD) has undergone 6 previous prototypes before establishing this current model. The current working model is composed of 3 elements: 1) Control/Battery Pack (CBP) 2) Valve assembly with separate Anvil Cap piece; 3) Remote Master Control Module (MCM). METHODS: The CBP consists of electronic and drive components. A printed circuit board, stepper motor and a lithium cell array are contained in the fully, hermetically-sealed waterproof titanium casing. The valve assembly consists of a cable link, a plunger and two shell halves. The cable link connects the cuff and plunger to the CBP. The CBP opens and closes the plunger via the drive assembly and has the ability to adjust the magnitude of closure force with 10 different settings based on commands made to the CBP using the Bluetooth telemetry system. Closure pressure of the FCD was determined from the device clamp force measured using a strain gauge load cell and amplifier in a bench top test stand. The typical closure pressure of a healthy human urethra ranges from 75 to 100 cm of water. The typical human urethra external size is approximately 24Fr or a 8mm diameter. The PSS-FCD has a clamp pad with two flexible silicone ridges of 4mm in width resulting in a total clamping area at urethra closure of 75mm2. The FCD produced an average clamp force of 3.67N resulting in a closure pressure of 0.057N/mm2 or ∼584 cm of water at the PSS-FCD clamp stroke setting of 08. The clamp force can be adjusted by changing the clamp stroke within the range of 04 to 10 during or after implant surgery as required to occlude fluid flow. At Phase IIb we implanted an additional 6 animals and performed subsequent full device replacement procedures in 3. RESULTS: The successful Phase I, Phase IIa and Phase IIb implants (and bench tests) have allowed the development of the newest Bluetooth telemetrically controlled AUS/valve. We have demonstrated biologic tissue compatibility without urethral trauma or erosion in all animals during survival experiments lasting more than 1 year. We demonstrated the easy feasibility of performing full FCD replacement on 4 animals without complications. CONCLUSIONS: The successful development of a remotely controlled AUS that allows for post-implant adjustable settings and remote telemonitoring capabilities is possible. Source of Funding: Precision Medical Devices