In some people between the ages of 20 and 40, the optic nerve in one eye becomes inflamed. The inflammation causes a gradual or sudden blurring of vision in the eye. In severe cases, the blurring progresses within a few days to temporary blindness. Often the eye is painful when you move it. If, in addition to the symptoms described, your fingers tingle or you have difficulty in urinating, this may mean that the condition is a symptom of multiple sclerosis .If your physician suspects you have multiple sclerosis, he or she may send you to a hospital for special tests or to another physician for a consultation, or second opinion. The treatment for optic neuritis is steroid medication, which hastens the spontaneous recovery that usually takes place. The problem may recur, however, in either eye. If it does recur, the disease usually does not respond to treatment, and it may cause progressive loss of vision.