Optic neuritis, also known as demyelinating optic neuritis, is the inflammation of the optic nerve due to damage to or loss of a protective covering called myelin that surrounds the optic nerve. Myelin is essential to the proper function of the optic nerve. A more general term, optic neuropathy, refers to abnormalities or nerve damage that results from disease, blocked blood flow, or toxic exposure. Optic neuritis is a variety of optic neuropathy.
The symptoms of optic neuritis include blurred vision, blind spots, reduced color vision, and pain with eye movement. These symptoms are generally followed by loss of vision. If left untreated, optic neuritis can lead to permanent optic nerve damage and loss of visual acuity.
Although the exact causes of optic neuritis are not yet fully understood, it occurs when the body’s immune system mistakenly attacks the myelin, which protects your optic nerve. When the myelin, which is essential for the proper functioning of the optic nerve, is damaged, the nerve cannot efficiently transfer electric signals/information from the eyes to the brain, which negatively affects vision.
Optic neuritis often occurs in conjunction with several medical conditions, disorders, and diseases including multiple sclerosis (MS), neuromyelitis optica, Lyme disease, systemic lupus erythematosus, sarcoidosis, ocular herpes, syphilis, measles, mumps, and sinusitis. Optic neuritis can also develop in reaction to certain medications.
The incidence of optic neuritis is most common among women; young adults between the ages of 20 and 40 are also at the greatest risk of developing the condition.
Diagnosis and Treatment
Eye care professionals commonly diagnose optic neuritis using a series of tests that include a routine eye exam, an ophthalmoscopy (to inspect the back of the eye for a swollen optic nerve), a pupillary light reaction test to check for abnormal function of the pupil, and blood tests.
Patients diagnosed with optic neuritis are much more likely to develop MS. As a result, if a patient is diagnosed with optic neuritis, an MRI will often be recommended to look for further signs of nerve damage and possible onset of MS.
Optic neuritis may clear up on its own. If it does not, an eye care professional will usually recommend a regimen of steroids administered both orally and intravenously to reduce inflammation and suppress the immune system.
If signs of MS are present in the patient, medications to slow the onset or development of MS will also be prescribed.