Hydrocephalus: A Review of Etiology-Driven Treatment Strategies

Abstract

Hydrocephalus is a broad term usually understood as cerebrospinal fluid (CSF) accumulation resulting in cerebral ventricular system expansion. The production of CSF is by the choroid plexus in lateral ventricles, flowing between the third and fourth ventricles and eventually to the subarachnoid space. It is critical for proper neuronal function. Hydrocephalus is a neurological pathology linked to high morbidity from neurocognitive and motor impairment. It is classified as either communicating or non-communicating. Communicating hydrocephalus is understood as a deficit at cranial arachnoid villi and granulation absorption sites. However, there has been evidence that extracranial lymphatic vessels in the ethmoid bone region also play a role, as indicated by decreased lymphatic absorption in rat models of hydrocephalus. Treatment typically involves surgical shunt placement or endoscopic third ventriculostomy (ETV) technique with or without choroid plexus cauterization (CPC). These surgical interventions have high failure risks and complications that require re-intervention, further increasing morbidity and mortality risks. To date, there are few nonsurgical treatment strategies, but many have proved limited benefit, and many patients still require surgery. This analysis lays out the typical treatments and explores new, innovative interventions by highlighting the active role of brain parenchymal tissue in the pathogenesis of hydrocephalus.

Keywords: beta-integrins; choroid plexus; intracranial pressure; parenchymal pressure; ventricular pressure.

Figure 1. Transport of cerebrospinal fluid through perineural olfactory space into the olfactory turbinates in the rat

Red arrow indicates the cribriform plate in A-C, E-F A and B) Evans blue dye in the turbinates (white arrows); C) Yellow Microfil depicting the lymphatic vessel highlighting the flow of CSF from the cistern magna subarachnoid space; D) Immunohistochemistry highlighting the lymphatic vessels of a neonatal rat; E) Schematic showing the sampling location to assess the role of CSF into the lymphatic vessel; F) Image of cribriform plate post-brain and olfactory bulb removal. CSF - cerebrospinal fluid Source: Nagra, 2010 [9]