Optic neuritis is caused by damage to the optic nerve due to acute or chronic inflammation. The optic nerve carries visual information from the eye to the brain. Inflammation of the optic nerve can cause damage to the myelin sheath covering it. Optic neuritis may occur in the form of loss of color vision, reduced visual field, and other symptoms. Optic neuritis is a serious condition that can lead to progressive vision loss or even blindness. Minimizing or preventing damage to the optic nerve is one of the primary reasons to seek medical care immediately if symptoms of optic neuritis occur or relapse.