Optic neuritis

Optic neuritis is inflammation of the optic nerve. The function of the optic nerve is to send impulses from your eyes to your brain – if this is disrupted, you may experience visual problems. Caused by inflammation of the optic nerve, optic neuritis can interfere with the passage of nerve impulses from the eye to the brain, affecting your vision.

Optic neuritis occurs when the immune system attacks the fatty covering called myelin that protects the optic nerve. When the myelin is damaged, the optic nerve is unable to send signals to the brain properly, which can affect vision.

Optic neuritis usually develops quickly, within a few hours or days. Symptoms associated with optic neuritis include:

• Pain when moving your eyes;
• Blurred vision;
• Loss of colour vision;
• Loss of peripheral vision;
• A hole in your field of vision;
• Headaches behind my eyes;
• Blindness, but this is rare.

Some of these symptoms are associated with other, more common eye diseases. However, if you experience any of these symptoms or sudden changes in your vision, you should have your eyes checked as soon as possible. Optic neuritis can occur in both adults and children. It usually affects one eye in adults and both eyes in children under 10 years of age.

The vast majority of people recover within a few weeks. In chronic cases, recovery can take much longer, but rarely more than a year. Usually, you will regain full or nearly full vision, although night vision problems may persist or colours may appear faded.

Inflammation of myelin (a substance that protects nerve cell outgrowths) causes pain and disrupts the optic nerve’s ability to send impulses from the eye to the brain, although it is not known why this happens.

Although rare, optic neuritis can also be caused by infections such as:

• Piggy;
• Measles;
• Tuberculosis;
• Lyme disease;
• Sinusitis;
• Shingles.

Optic neuritis can be detected by a thorough eye examination. During the consultation, visual acuity, colour perception and pupillary response to light are assessed. The fundus of the eye is also examined with the pupils dilated, with special attention paid to the optic nerve.

If your eye specialist suspects that you have optic neuritis, you will be referred to the hospital’s ophthalmology department, where the diagnosis will be confirmed and a treatment plan will be developed.