Causes and treatments for optic neuritis

Optic neuropathy refers to optic nerve abnormalities or damage caused by blocked blood flow, toxic exposure or any other factor. This ocular problem has major symptoms such as sudden or gradual loss of vision. Once the affected eye moves, there may or may not be pain. In addition, some patients may lose a certain degree of their color vision. Optic neuropathy even has primary and secondary forms. Yet another less serious eye condition is optic neuritis, which is the inflammation of the optic nerve. Similar to optic neuropathy, optic neuritis may cause complete or partial vision loss. But in general, it is relatively less severe.

Noticeable and unnoticeable symptoms of optic neuritis

People with optic neuritis may have symptoms such as blurry vision, distorted vision, decreased color vision, blind spots and will potentially suffer vision loss. In addition, it is estimated that about 92% of optic neuritis patients feel pain in the eye, which sometimes precedes the appearance of 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.

Possible causes of optic neuritis

Some signs of optic neuritis can be detected by certain eye tests, including intraocular pressure (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 of the eye. 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.

An effective treatment for optic neuritis

Treatments that were ever used include intravenous (IV) steroids, oral steroids and placebo. However, the most widely used treatment typically includes three days 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 incidence of optic neuritis and the risk of developing MS. Separate placebo treatment is much less effective.

Statistics of optic neuritis cases

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. Some doctors may recommend a magnetic resonance imaging (MRI) in order to make an early detection of an ongoing development of MS.