Optic Neuritis

Optic neuritis is the medical term used to describe an inflammation, or swelling, of the optic nerve.

The optic nerve allows us to see by carrying images from our eye to our brain.

The optic nerve is like a cable of electrical wires, and consists of about 1,200,000 separate tiny wires of nerve fibers. Each wire carries a part of the visual information we see to the brain. If some or all of the nerve fibers become inflamed and do not function properly, our vision becomes blurred.

With optic neuritis, the nerve tissue becomes swollen and the nerve fibers do not work properly. If many of the nerve fibers are involved, vision may be very poor, but if the optic neuritis is mild, vision is nearly normal.

CAUSES

Various diseases and conditions may cause optic neuritis. The nerve of one or both eyes may be affected.

Some people, especially children, develop optic neuritis following a viral illness such as mumps, measles or a cold. In others, optic neuritis may occur as a sign of a neurological disease such as multiple sclerosis. Optic Neuritis can also develop when the nerve is starved of oxygen, such as in diabetics or following a stroke.

SIGNS/SYMPTOMS

Optic neuritis usually occurs suddenly. You may notice the following symptoms:

Blurred vision in one or both eyes, especially after exercising or a hot bath;
Vision is dim, as if the lights were turned down;
Color appears dull or faded;
There may be pain behind the eye, particularly when moving the eyes.

A careful description of these symptoms is important to your eye doctor in the diagnosis of optic neuritis. He or she will perform a complete medical eye examination.

Since optic neuritis can be confused with many other causes of poor vision, an accurate medical diagnosis is important. Other tests which may be performed by your ophthalmologist include color vision, side vision, and the reaction of the pupil to light. Ultrasound, MRI scans, or visual brain wave recordings might be ordered.

If a cause can be found and treated, further damage may be prevented.

TREATMENT

Fortunately, most people recover normal vision without any treatment. Although some people may have visual defects from optic neuritis, these are usually very mild.

When medical intervention is necessary, steroids, or anti-inflammatory meds, may be used. In rare instances, surgery may be needed to reduce the pressure inside the optic nerve.