Introduction:
The post-COVID complications that affect the body includes neurologic problems, breathing difficulty, and damage to the lungs, kidney, liver, and other organs. Hyperacute optic neuritis is a severe condition that causes damage to the optic nerve that helps in vision. The optic nerve becomes inflamed and in severe cases, it goes on to develop multiple sclerosis. It causes demyelination of the optic nerve. In optic neuritis, the immune system attacks its own body tissues for some unknown reason.
What Is Optic Neuritis?
Optic neuritis is a condition causing swelling and inflammation of the optic nerve, which transmits visual information to the brain and creates visual images. Optic neuritis usually affects only one eye. The exact cause of optic neuritis is unknown, most commonly it occurs when the body’s immune system attacks the optic nerve. Certain autoimmune conditions like multiple sclerosis are closely associated with optic neuritis.
What Are the Symptoms of Optic Neuritis?
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Pain - a most common symptom, the pain worsened with movement of the eye, experienced at the back of the eye.
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Vision loss in one eye.
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Loss of vision field.
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Blurry vision.
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Dim vision.
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The color appears dull and faded.
How Is Hyperacute Optic Neuritis With COVID-19 Infection Related?
COVID-19 infections leave several neuro-ophthalmic conditions that affect the optic nerve and vision. COVID-19 is a group of symptoms that are hyperinflammatory in nature. COVID-affected people show increased chances for autoimmune reactions. The most common neurologic sequelae associated with COVID infection is hyperacute optic neuritis. It is characterized by unilateral vision loss and pain in eye movement. Acute optic neuritis is the first noticed sign of multiple sclerosis. It can also occur as a complication of viral infections like influenza, mumps, rubella, and hepatitis A and B. Optic neuritis can be seen as a complication after vaccination for COVID-19 or hepatitis vaccination.
The symptoms of optic neuritis associated with COVID-19 can range from mild to moderate. The symptoms associated with optic neuritis include pain with eye movement, decreased visual acuity, headache, and optic nerve enlargement. Both unilateral and bilateral involvement of the eye is seen. The neurological examination was found to be normal. Similar symptoms of optic neuritis are also seen in patients after receiving the COVID-19 vaccine and its booster dose. In patients who had COVID-19 infection, optic neuritis occurs days or weeks after the initial infection. In patients who received the COVID-19 vaccine, symptoms developed after two hours of vaccination.
Optic neuritis was observed in patients who had COVID-19 earlier and in some people, symptoms developed only after vaccination.
What Causes Optic Neuritis After a COVID-19 Infection?
Following infection with COVID-19, the immune system of the body starts producing antibodies against COVID-19. COVID-19 vaccines help in developing immunity against the virus. Following the vaccination our body produces memory T lymphocytes and B lymphocytes that helps to fight against viruses when infected.
A person who had COVID-19 infection earlier and received the vaccination triggers a rapid secondary reaction that results in optic neuritis. Viral antigens from the vaccine trigger the immune system to attack the myelin proteins in the central nervous system and lead to optic neuritis.
How Optic Neuritis Is Diagnosed?
Optic neuritis is mainly found as associated with multiple sclerosis. In patients reporting pain in the eye and blurred vision following COVID-19 vaccination or a history of viral infection, a thorough examination is done to rule out optic neuritis. Diagnosis includes brain MRI (magnetic resonance imaging) and orbits with contrast along with laboratory tests.
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Routine Eye Examination - This includes checking vision, the ability to identify color, and measuring peripheral or side vision. Also examination for other symptoms like pain and swelling.
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Ophthalmoscopy - Ophthalmologist uses bright shiny light to examine the structures at the back of the eye. It helps in the evaluation of the optic disc, which will be swollen in patients with optic neuritis.
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Magnetic Resonance Imaging (MRI) - Brain MRI and orbits with contrast are done.
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Pupillary Light Reaction Test - The doctor uses bright light to see the pupillary response. In patience with optic neuritis, the pupils will not constrict as much as in a person with healthy eyes.
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Optical Coherence Tomography (OCT) - This procedure measures the retinal nerve fiber layer, which will be thinner in optic neuritis.
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Visual Field Test - This test measures the peripheral or side vision. The peripheral vision will be lost or changed in the pattern.
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Blood Test - Certain blood tests are carried out to check for the presence of any infections.
How Is Optic Neuritis Treated?
In the majority of cases, optic neuritis resolves on its own. If no improvement is seen during our period steroid medications are used to reduce inflammation of the optic nerve. Steroid medications are given intravenously. This medication fastens the recovery without affecting the vision. The possible side effects of steroid medications are mood swings, stomach upset, weight gain, insomnia, and flushing of the face. If the steroid medication also fails and vision loss persists, another treatment plasma exchange therapy can be done. This treatment might help in recovering vision. Studies are ongoing in plasma exchange therapy to confirm the effectiveness of plasma exchange therapy on optic neuritis.
In patients with optic neuritis associated with multiple sclerosis, treatment for multiple sclerosis can help in reducing symptoms of optic neuritis.
What Is the Prognosis of Treatment for Optic Neuritis?
The majority of the people regain normal vision and symptomatic reduction in optic neuritis within six months. There is a higher risk of multiple sclerosis in patients with recurring episodes of optic neuritis.
How to Prevent Optic Neuritis?
Optic neuritis occurs mostly following a viral immune infection. Reducing the risk of acquiring viral respiratory infection COVID-19 decreases the risk of optic neuritis. The same preventive steps adopted to stop the spread of viral infections are adopted. Proper hand-washing techniques, and avoiding frequent touching of the face with unclean hands are a few of them.
Conclusion:
Hyperacute optic neuritis is an immune condition where the immune system attacks the optic nerve, resulting in pain in the eye and vision loss. It occurs as a complication of covid 19 infection or in cases after receiving covid - 19 vaccination. Proper medical treatment can help reverse symptoms, without vision loss.
