Symptoms and Signs
Optic neuritis is usually seen in young females between the ages 20-45 yrs.
Sudden or occasionally gradual reduction in vision commonly seen unilaterally (one eye) may involve the other eye also. Reduction in vision progresses over two weeks after which vision gradually improves over weeks to months. The visual recovery is usually complete, but rarely there may be residual loss in vision, especially after repeated attacks. Visuals symptoms are exaggerated by exercise or by taking a bath with hot water.
Reduced contrast sensitivity along with reduced light brightness appreciation typically resulting in washed out vision.
Pain in and around the eye is also a common symptom in patients suffering from optic neuritis. It is seen in around majority (90%) of the patients. The characteristic feature of this pain is exaggeration with eye movement.
In addition to pain and visual blurring flashes of light or showers of sparks may be precipitated by eye movements in about 30% of the patients.
Symptoms of optic neuritis may be the presenting complaints of multiple sclerosis. Hence multiple sclerosis should be ruled out in all cases of optic neuritis.
Signs of Optic Neuritis
Signs are the findings seen on examination by a doctor in a patient with optic neuritis. Most commonly seen characteristic finding is reduced visual acuity. Central scotoma (central non seeing area in the affected eye), defective color vision out of proportion to the loss in visual acuity, reduced contrast sensitivity, reduced light brightness appreciation.
Defective functioning of the pupil (a diaphragm that controls the amount of light entering the eye) seen as relative afferent pupillary defect when only one eye is affected or when one eye is affected more than the other in bilateral cases.
The optic nerve when seen through an instrument called an ophthalmoscope appears swollen. It may even appear absolutely normal in cases where the inflammation in the optic nerve is typically behind the eye ball (retro-bulbar neuritis).