The optic nerve is very important for the normal vision of human eyes. Any inflammation or irritation in this nerve leads to a serious optical problem called optic neuritis. This condition might occur in one or both eyes due to diverse reasons.
What is optic neuritis?
An Inflamed or irritated optic nerve leads to a medical condition called optic neuritis. Since the optic nerve carries messages from the eyes to the brain, its inflammation may cause temporary blindness.
Optic neuritis signs and symptoms can be the first indication of MS (multiple sclerosis), or they may occur later in the course of MS.
The insulating myelin sheath covering the optic nerve can be badly damaged by autoimmune diseases such as Multiple sclerosis , resulting in this illness. Usually, it occurs only in one eye and having this problem in both eyes is very rare. Besides MS, optic nerve inflammation may occur with other conditions, along with infections or immune diseases like lupus. Another disease called neuromyelitis optica, although rarely, causes inflammation of the optic nerve and spinal cord.
What are the symptoms of optic neuritis?
- Temporary vision loss in the affected eye
- Dull pain in the eye that increases due to movements of the eyeball
- Sudden flashes of light seen by the affected eye
- Colors appear much less bright
- Inability to see things sidewise
- Blurry vision at times
- Seeing a dark hole at the centre while looking straight
What are the causes of optic neuritis?
While exact reason for optic neuritis is unknown, doctors suggest a few factors that can be responsible for this disease.
- Multiple sclerosis is an auto-immune ailment that damages the myelin sheath of the optic nerve and other nerves linked to the brain. This ailment is closely interrelated with optic neuritis.
- Myelin oligodendrocyte glycoprotein (MOG) antibody disorder is one that creates inflammation at the optic nerve and other parts of the nervous system, including the brain and the spinal cord. Usually, recovery from MOG attacks is better compared to recovery from neuromyelitis optica.
- Neuromyelitis optica: In neuromyelitis optica, inflammation affects the optic nerve and spinal cord.
- Infections: Bacterial infections, including cat-scratch fever, syphilis and lyme disease, or viruses like herpes, measles, and mumps, can cause optic neuritis.
- Drugs and toxins. Methanol, a common ingredient in solvents, paints and antifreeze and, Ethambutol, which is used to treat tuberculosis, are associated with optic neuritis
- Other diseases: Diseases like lupus, sarcoidosis and Behcet’s disease can cause recurrent optic neuritis.
When to see a doctor?
You should contact an eye specialist immediately when you find any of the abnormalities, mentioned above, in your vision. You also need to inform your doctor if there is no sign of improvement even after receiving treatment for curing optic neuritis. Negligence in this matter can result in the permanent loss of vision, even in both eyes.
How is Optic Neuritis treated?
An eye specialist will conduct some clinical examinations to monitor the condition of your eye and whether it is affected by optic neuritis. He/she may also conduct an ophthalmoscopy. The reaction of your pupil is also checked. He/she may also recommend some blood tests, MRI scan and visual field test to confirm this disease accurately. If a person has optic neuritis, and has two or more brain lesions evident on MRI scans, he/she may benefit from multiple sclerosis (MS) medications like interferon beta-1b or interferon beta-1a, that may delay or help prevent MS.
Usually, the condition of optic neuritis is expected to improve naturally within a few days. However, the doctor may prescribe some steroids to decrease the degree of inflammation in your optic nerve. Doctors administer intravenous injections with steroid medicines to speed up the recovery of their patients. Plasma exchange therapy is also preferred by some eye specialists, depending on the condition of their patients.
Most people regain close to normal vision within six months after an optic neuritis episode.
People whose optic neuritis returns have a greater risk of developing MS, neuromyelitis optica or MOG antibody associated disorder. Optic neuritis without underlying conditions has better long-term prognosis for vision than that which occurs in people with MS or neuromyelitis optica.
Frequently Asked Questions (FAQs)
Which age group is more prone to optic neuritis?
People in the age group of 20–40 are found to be more at risk. It is also seen that women are more prone to this disease compared to men of the same age. At times, genetic factors might also be responsible for the occurrence of this disease.
What are the probable complications from optic neuritis?
Loss of color perception can be permanent in some patients even after recovering from optic neuritis. Some people may also lose their vision permanently due to the severity of this disease. The optic nerve can be damaged beyond repair if not treated on time. Some medications used for this treatment may have some adverse side effects.
What are the probable side effects of taking steroid medications?
You may suffer from insomnia, unexpected weight gain, mood swings and stomach irregularities after taking steroid injections for curing this optic nerve inflammation. However, these side effects differ from person to person and depend on the current health condition of a patient.