The optic nerve is an important nerve of the eye that carries electrical impulses to the brain. This nerve is affected by a condition called optic neuritis that is explained in the following paragraphs.
What is Optic Neuritis?
The inflammatory demyelinated condition of the optic nerve fibers is called as optic neuritis. This condition leads to loss of vision, eye pain, loss of color vision and problems with the visual field. The inflammation may occur due to the cells of the immune system attacking any virus or foreign material near the nerves or as a result of autoimmune diseases. Optic neuritis is often associated with multiple sclerosis. However, not all who develop optic neuritis will go on to develop multiple sclerosis.
Symptoms of Optic Neuritis
Optic neuritis is usually causes symptoms in only one eye. The symptoms of optic neuritis include:
- Eye pain that worsens with eye movement
- Temporary loss of vision in affected eye. The extent of loss of vision varies from individual to individual. This vision loss can last for a few hours to days.
- In a few cases, loss of vision is permanent
- Loss of color vision
- Appearance of flashing lights in vision (photopsias)
Causes of Optic Neuritis
Optic neuritis can affect any person at any age. The exact cause of optic neuritis is still unknown. In some cases, it occurs due to the immune system attacking the myelin sheath of the optic nerve cells by mistake. This leads to inflammation and damage of the optic nerve. Other causes of optic neuritis include:
- Infections such as viral encephalitis, meningitis, sinusitis, tuberculosis, syphilis, HIV
- Chemical or drug poisoning like methyl alcohol, lead, arsenic, certain antibiotics, etc.
- Autoimmune diseases like Graves’ disease
- Nerve diseases like multiple sclerosis, Shilder’s disease, neuromyelitisoptica
- Gullain-Barre syndrome
- Immune response reaction after vaccination
Diagnosis of Optic Neuritis
Optic neuritis is diagnosed with the help of physical examination and symptoms. These diagnostic tests include:
- Routine eye examination
- Pupillary light reaction test
- Magnetic resonance imaging
- Blood tests
Treatment of Optic Neuritis
Optic neuritis resolves on its own as the inflammation on the optic nerve subsides. In some cases, steroids are given intravenously to reduce inflammation. If the inflammation persists and loss of vision continues, plasma exchange therapy is given to help recover vision.
If two more lesions on the brain are visible on the MRI scan one is prone to multiple sclerosis. In this case, the doctor will prescribe interferon beta-1a and interferon beta-1b.
Prognosis for Optic Neuritis
People with optic neuritis recover within 12 months. However, those with multiple sclerosis may have recurrent episodes of optic neuritis.
Optic neuritis can be a scary condition, especially when it leads to loss of vision. Speak to your doctor immediately, if you experience blurred vision or any vision distortion. If treated properly, it will help one regain their lost sight successfully.
Written by: Saptakee sengupta
Date last updated: April 05, 2015