Causes and treatments for optic neuritis

Optic neuropathy refers to optic nerve abnormalities or damage caused by blocked blood flow or toxic exposure. Another less serious eye condition is optic neuritis, which is inflammation of the optic nerve.

People with optic neuritis may have symptoms such as blurry vision, distorted vision, decreased color vision, blind spots and potential vision loss. Underlying changes caused by optic neuritis can be abnormal pupil appearance. The pupil performs abnormally that it will dilate instead of constricting in the presence of bright light. And the optic nerve may appear normal or swollen.

Eye exams can detect signs of optic neuritis, including IOP measurement and pupil dilation for better eye interior structures viewing. Optic neuritis is caused by loss and damage to protective nerve coverings that surround the nerve. As a result, optic neuritis occurs commonly in people with multiple sclerosis (MS), which are caused by immune system’s attack towards those optic nerve coverings. Related nerve damage in MS can also lead to loss of mobility and sensory function. There are still other causes of optic neuritis and neuropathy, such as certain infections, ocular herpes, sinusitis, neurological disorders, nutritional deficiency and toxins including alcohol and tobacco.

Treatments that were ever used include intravenous (IV) steroids, oral steroids and placebo. However, the most widely used treatment is typically three day of IV steroids, followed by 11 days of oral steroids, according to the results of a landmark series of studies known as the Optic Neuritis Treatment Trials (ONTT). The ONTT has revealed that steroids can not affect the final visual outcome in neuritis patients. However, the combination of IV steroids and oral steroids can both reduce the recurrence of optic neuritis and the risk of developing MS. Separate placebo treatment is much less effective.

There are several prognoses for those who have optic neuritis. Statistics show that about 95% of optic neuritis patients will recover much of their vision within six months, and less than 20% will suffer from a second optic neuritis or an optic neuritis in the other eye. Doctors may recommend a MRI to prevent the development of MS.