Optic neuritis, also known as retrobulbar neuritis, is inflammation of the optic nerve that prevents the transmission of information from the eye to the brain. This happens because the nerve loses the myelin sheath, a layer that lines the nerves and is responsible for the transmission of the nerve impulses.
This disease is more common in adults 20 to 45 years old, and causes partial, or sometimes total, loss of vision. It usually affects one eye, although it can also affect both eyes and may also cause eye pain and change in the identification or perception of colors.
Optic neuritis mainly arises as a manifestation of multiple sclerosis, but can also be caused by a brain infection, a tumor or by poisoning by heavy metals, such as lead, for example. Recovery usually happens spontaneously after a few weeks, however, the doctor may also use steroids to help speed recovery in some cases.
Main symptoms
The symptoms of optic neuritis are:
- Loss of vision, which may be partial, but in the most severe cases may be total, and one or both eyes;
- Eye pain, which worsens when moving the eye;
- Loss of ability to distinguish colors.
Vision loss is usually temporary, however, and may still have sequelae such as difficulty identifying colors or having blurred vision. Check for other signs and symptoms of vision problems that are warning signs.
How to identify
The diagnosis of optic neuritis is done by the ophthalmologist, who can perform tests that evaluate the vision and condition of the eyes such as visual field, visual evoked potential, pupillary reflexes or evaluation of the fundus of the eye, for example.
In addition, a brain magnetic resonance imaging (MRI) scan may be ordered, which helps identify brain changes such as those caused by multiple sclerosis or a brain tumor.
What are the causes
Optic neuritis usually arises due to:
- Multiple sclerosis, which is a disease that causes inflammation and loss of the myelin sheath of brain neurons. Check out what is and how to identify multiple sclerosis;
- Brain infections, such as viral meningitis or encephalitis, caused by viruses such as chickenpox or herpes, or tuberculosis involvement, for example;
- Brain tumor, which can compress the optic nerve;
- Autoimmune diseases ;
- Graves 'disease, which causes eye involvement called Graves' orbitopathy. Understand how and how to treat this disease;
- Intoxication by drugs, such as some antibiotics, or by heavy metals such as lead, arsenic or methanol, for example.
However, in many cases, the cause of optic neuritis is not detected and is called idiopathic optic neuritis.
Treatment for Optic Neuritis
In many cases, optic neuritis has a spontaneous remission, and the signs and symptoms improve without the need for a specific treatment
However, it is always important to follow up with the ophthalmologist and neurologist, who can evaluate the need to use medications, such as corticosteroids to reduce nerve inflammation, or surgery to decompress the optic nerve, which may be necessary in cases of tumor, for example.
Although recovery may be complete in some cases, some sequelae may remain, such as difficulty in differentiating colors, visual field changes, sensitivity to light, or difficulties in evaluating distances, for example.