Technologies

No way currently exists to prevent or cure hydrocephalus, which is the abnormal accumulation of cerebral spinal fluid (CSF) in the brain. The most effective treatment involves surgical insertion of a shunt to move excess CSF from the brain into the venous system or other receptive cavities. Most shunts contain valves that open when the pressure difference across the valve reaches a predetermined amount. However, gravity-induced pressure changes caused by a re-positioning of the head can open the valve even in the absence of CSF buildup, resulting in excess siphoning of CSF from the brain. UW-Madison researchers have now created a shunt with a new type of ventriculoperitoneal valve that does not allow undesired siphoning of CSF. The shunt includes an inlet port, an outlet port and a fluid channel in between. It also contains a valve located between the two ports and a valve-actuating member, such as a piston, which holds the valve closed.

As CSF accumulates, it puts pressure on the piston, which is held in place by a circumferential rubber skirt that acts as a spring. When the pressure reaches a predetermined level, a channel within the piston aligns with the fluid channel, allowing CSF to flow from the head through a catheter. The valve is designed so that the piston responds to the build-up of CSF, but not to changes in CSF flow due to gravity. Thus, the valve opens only in response to intracranial pressure, eliminating the problem of gravity-induced siphoning seen in conventional shunts.

The Wisconsin Alumni Research Foundation (WARF) is seeking commercial partners interested in developing a shunt with a new type of ventriculoperitoneal valve that does not allow undesired siphoning of CSF.