Optic neuritis is an inflammation of the optic nerve, there are many etiologies however the most frequent is demyelination which is commonly in association with MS. ON is the first feature of MS in about 20% of patients. The presenting symptoms of optic neuritis can be pain on ocular movement, visual field loss, decreased visual acuity, and loss of color vision. Signs that can be seen on ocular and fundoscopic examination are a RAPD and an abnormal appearance of the optic nerve. ON is more common in young adults (20-45 years) and is three times more likely to occur in women than in men. Two phenomena have also been described in ON, the Uhthoff and the Pulfrich. Uhthoff phenomenon is the worsening of vision upon increasing body temperature, and the Pulfrich phenomenon is the false appearance of depth perception in a lateral movement, as in a side-to-side pendulum swing seeming to appear to move in an elliptical manner. These phenomena are related to the slowing of nerve conduction in the affected optic nerve. Many of the clinical findings and comments on treatment plans came from the ONTT carried out from 1988 to 2003 on 454 participants. The results had shown that the most common visual field defect in the affected eye was diffuse visual field loss (48%), followed by altitudinal defects (15%), central or cecocentral scotoma (8.3%), arcuate or double arcuate (4.5%), hemianopic defects (4.2%). Vision tends to return to normal or almost normal without treatment in a couple months, however the ONTT has shown that the most effective treatment method for ON is a course of IV corticosteroids followed by oral corticosteroids as this can lower the risk of developing MS.