eye disorders
Optic Neuritis
Symptoms and Signs of Optic Neuritis
The main symptom of optic neuritis is vision loss, frequently maximal within several days and varying from a small central or paracentral scotoma to complete blindness. Most patients have mild eye pain, which often feels worse with eye movement. The most characteristic findings include reduced visual acuity, a visual field deficit, and disturbed color vision (often out of proportion to loss of visual acuity). An afferent pupillary defect is usually detectable if the contralateral eye is unaffected or involved to a lesser degree. Testing of color vision is a useful adjunct, although 10% of males have congenital color blindness, producing false-positive results. In about two thirds of patients, inflammation is entirely retrobulbar, causing no visible changes to the optic nerve head. In the rest, disk hyperemia, edema in or around the disk, vessel engorgement, or a combination is present. A few exudates and hemorrhages may be present near or on the optic disk, but this is rare for most cases of optic neuritis. 