Communicating hydrocephalus results from the impaired absorption of cerebrospinal fluid (CSF) from the intracranial subarachnoid space into the venous system. Excess CSF in the subarachnoid space increases intracranial pressure and can cause significant symptoms ranging from headache to neurological dysfunction, coma and death. The disease is one of the most common and important neurosurgical conditions affecting both children and adults. Conservative estimates indicate that more than 320,000 Americans are living with the disease, and the Hydrocephalus Association reports that the U.S. disease prevalence exceeds one million patients.
The current treatment for communicating hydrocephalus – ventriculo-peritoneal shunt (VPS) placement – requires an invasive surgical procedure performed under general anesthesia, and typically requires post-procedure hospitalization ranging from two to four days. The average VPS procedure cost in the United States is estimated to be approximately $35,000.
“despite many advances in the design of the CSF shunt, there have been few improvements in the rate of shunt malfunction, with greater than 40% of first-time shunts failing within 2 years.”
Despite six decades of experience and refinement, VPS devices remain subject to a high rate of failure. Proceedings from the most recent NIH-sponsored symposium on hydrocephalus research report that “despite many advances in the design of the CSF shunt, there have been few improvements in the rate of shunt malfunction, with greater than 40% of first-time shunts failing within 2 years.1” Common VPS failure modes include infection, catheter obstruction, disconnected componentry, and CSF over-drainage. Each VPS failure typically requires a “revision,” an invasive surgical procedure necessary to replace or repair the failed VPS.
Due to the rate of failure of the current approach, it is estimated that approximately half of 130,000 VPS procedures performed annually in the United States and Western Europe are revision procedures for failed VPS devices.