Influence of cerebrospinal fluid pressure and its composition around the optic nerve on the development of glaucoma. Overview

Growing evidence in the literature provides strong support for the concept that cerebrospinal fluid pressure (CSFP) plays a role in the pathogenesis of glaucoma. The CSFP forms the counterbalance to the intraocular pressure (IOP) across the optic disc. The pressure difference across the lamina cribrosa seems to be more important than the IOP on its own. This trans-lamina cribrosa pressure difference depends on the imbalance between the IOP and the CSFP, and their fluctuations . Several studies have demonstrated that this pressure difference is higher in patients with normal tension glaucoma (NTG), providing an explanation for the mystery of NTG. Secondly, the CSF around the optic nerve may have a deficient clearance. Possible compartmentalization of this subarachnoidal space around the optic nerve has been documented. Also changes in general CSF circulatory physiology result in decreased CSF turnover, decreased CSFP and CSF stasis. Given the central role of CSF turnover in the clearance of potentially toxic metabolites from the brain, one might expect that CSF circulatory dysfunction could ultimately result in reduced neurotoxin clearance in the subarachnoid space surrounding the optic nerve and lead to glaucomatous damage.