Effects of Hydrocephalus on Rodent Optic Nerve and Optic Disc

Abstract

Hydrocephalus affects 1 in 1,000 newborns and nearly 1,000,000 Americans, leading to an increase in intercranial pressure due to the build-up of cerebrospinal fluid. There are numerous complications that arise as a result of hydrocephalus, but this study focuses on optic disc edema. The subarachnoid space surrounding the optic nerve contains cerebrospinal fluid. The cerebrospinal fluid increases in hydrocephalus, putting pressure on the optic nerve. The additional intracranial pressure has been proposed to cause axoplasmic stasis within the retinal ganglion cell axons, leading to axonal damage and retinal ischemia. The purpose of this study was to determine the effects of hydrocephalus on the optic disc and retina in several animal models of hydrocephalus. This study uses two genetic and two injury-induced models of hydrocephalus in addition to immunohistochemistry and histological stains to examine the optic disc, thickness of retinal layers, and numbers of retinal cells. This study serves as preliminary work to help build the case that hydrocephalus causes cell loss in the retina, as well as swelling of the retinal ganglion cell axons, leading to axoplasmic stasis and cell death.