Optic neuropathies are degenerative diseases of the retina that result from the destruction of the optic nerve. They can result either from an excess of intraocular pressure, as is the case for glaucoma, or from oxygen deprivation in the case of ischemia of the eye such as is the case with NAION. The optic nerve is made up of the axonal extensions of retinal neurons, and once damaged, these extensions degenerate and the neurons of the retina die.
Anterior ischemic optic neuropathies (AION), sometimes referred to as “optic disk infarction,” result in the sudden loss of vision of an eye.
The vast majority (90%) of AION cases are non-arteritic (NAION), that is, they are not related to inflammation of the vessel wall NAION is an orphan disease with an incidence of 2.5-10 / 100’000 among individuals over 50, leading to partial or total vision loss in one eye in 60-70% of patients.
The pathophysiology of the disease is unknown, but it is related to poor circulation in the optic nerve head. Non Artheritic Ischemic Optic Neuropathy is often associated with diabetes mellitus, elevated intraocular pressure, high cholesterol, a drop in blood pressure, and sleep apnea. The second eye is affected for 15 to 24% of patients within 5 years of first eye involvement.
To date, there is no approved treatment for NAION.