Walsh & Hoyt: Papilledema: Pathogenesis

Any unifying mechanism for papilledema must account for (a) transient unilateral or bilateral visual obscurations; (b) edema localized to the optic nerve head; (c) flattening of the posterior sclera as demonstrated by neuroimaging techniques, and (d) venous distension and cessation of venous pulsations. Various hypotheses have been proposed over the years, including direct infiltration of the optic nerve head by CSF, obstruction of posterior flow of intraocular fluid, inherent turgescence of prelaminar nerve substance, swelling of glia, absence of the restraining influence of Muller cells in the peripapillary retina, disequilibrium of hydrostatic pressure in the tissue and bloodstream, and compression of the central retinal vein as it traverses the subarachnoid space or cavernous sinus with elevated central venous pressure.