Incontinence is among the most common ailments – approximately 8 million people suffer from it in Germany alone. Together with DUALIS MedTech GmbH, Fraunhofer EMFT is working on a new artificial sphincter technology, which allows a combination of diagnostics and therapy (theranostics). As with passive systems, the sphincter function is realized by opening and compressing the urethra using a fluid-filled cuff. In contrast to traditional methods, the quantity of hydraulic fluid in the cuff – and thus the closure function – is not controlled manually, but by the interaction of active microelectronic components: a micropump is responsible for emptying, a microvalve for filling the cuff. Both components are currently being developed at Fraunhofer EMFT. The actuators meet essential requirements such as high flow rates, fast reactivity, small size, and low energy consumption. The new developments must be both corrosion-resistant and MRI-capable.

The pressure control algorithm ensures that the pressure is automatically readjusted when the threshold values in the cuff and/ or reservoir are exceeded – for example, at unforeseen stresses such as coughing or laughing – so that continence is ensured at all times. Using a programmer, the attending physician can adjust the tissue-defying normal pressure at any time, wirelessly without surgery. The patient can also manually adjust the cuff pressure with a remote control (for example, by means of predetermined modes such as sports or night mode).

The development is supported by the Bavarian Research Foundation. Fraunhofer EMFT presented the current development level of the sphincter system at last year’s Compamed trade fair.