The PS Medical valve is designed to minimize over drainage of cerebrospinal fluid (CSF) and maintain intraventricular pressure (IVP) within a normal physiologic range, regardless of patient position. The normally closed Delta chamber mechanism opens in response to positive ventricular pressure. Working with the membrane valve, this mechanism minimizes over drainage by utilizing the principles of hydrodynamic leverage. All Delta valves incorporate a central reservoir dome, occluders for selective flushing, and a non-metallic design. The valves are fabricated of dissimilar materials — polypropylene and silicone elastomer — reducing the chance of valve sticking and deformation. Radiopaque indicators provide an indication of valve-to-catheter approximation.
Silicone for Prosthetics
One good source of information is http://www.factor2.com/. For technical support contact David Trainer.
The incredible story of Mark Tatum found on the factor2 website shows one of the most miraculous uses of silicone rubber in prosthetics. For more on this story see http://www.factor2.com/Overview_Pages/mark_tatum.asp.