The csf accumulator: Its role in the central nervous system and implications for advancing hydrocephalus shunt technology

Abstract

The ability of the central nervous system (CNS) to store and release fluid energy plays an important role in both health and disease. The stored fluid energy is the product of the fluid volume and pressure. How changes in CNS fluid (CSF, blood, or extracellular fluid) energy are distributed is determined by the compliance of the fluid containers and their arrangement. Hydrocephalus and related diseases not only interfere with the absorption of CSF but also interfere with the exchange of CSF in response to positional changes, cardiorespiratory and intraperitoneal energy changes. While shunts allow for the diversion of CSF when the intracranial energy exceeds the absorbing receptacle energy, they do not normalize the return of CSF to the intracranial compartment as needed with the intracranial blood volume or pressure decreases (the accumulator function of the CNS's CSF). A CSF shunt that has an artificial accumulator proximal to the valve can potentially restore the accumulator function towards normal and prevent some of the complications associated with CSF overdrainage.