Optic neuritis is a visual impairment caused by inflammation of the eye nerve (optic nerve). This condition often occurs in people with multiple sclerosis, which is characterized by blurred vision in one of the eyes and pain in the eyes.
The optic nerve carries light signals from the eye to the brain, so a person can see. In case of inflammation, infection, or damage to the optic nerve, the sufferer is unable to see clearly.
Optic neuritis can occur in older persons as well as children, but is most commonly experienced by women aged 20-40 years. Optic neuritis usually only attacks one eye, but in some cases it can also occur in both eyes.
Optic Neuritis Risk Factors
There are several factors that increase a person’s risk of developing optic neuritis, including:
- Gender, usually women is more affected by this disease
- Age, people aged about 20-40 years are more likely to occur this disorder
- Genetic mutations, the occurrence of genetic mutations in a person increases the risk of having optic neuritis abnormalities.
Optic Neuritis Causes
Optic neuritis can be caused by several possibilities, such as:
Multiple Sclerosis
Multiple sclerosis is a disease caused by an autoimmune system that attacks the myelin sheath that covers nerve fibers in the brain and spinal cord. In people with optic neuritis, the risk of developing multiple sclerosis after one episode of optic neuritis is about 50 percent to occur in life. A person’s risk of multiple sclerosis after optic neuritis increases further if an MRI scan shows lesions on the brain.
Neuromyelitis Optica
In this condition, it occurs due to repeated inflammation of the optic nerve and spinal cord. Neuromyelitis optica has similarities to multiple sclerosis, but neuromyelitis optica does not cause damage to nerves in the brain as often as multiple sclerosis.
- Bacterial or viral infections, and related diseases (including tuberculosis, Lyme disease, hepatitis B, HIV, shingles, encephalitis, sinusitis, and many others)
- Cranial arteritis, or inflammation of the arterial membranes of the skull.
- Diabetes.
- Sarcoidosis.
- Bee sting.
- Systemic lupus.
- Vasculitis.
- Side effects of certain medications.
- Toxins such as lead, quinine, arsenic, and methyl alco**hol.
- Radiation therapy.
- Inherited optic neuropathy.
- Vitamin B12 deficiency.
Optic Neuritis Symptoms
Optic neuritis generally affects one eye. Signs and symptoms that occur can be:
- Pain. Most individuals with optic neuritis complain of eye pain exacerbated by eyeball movement. Sometimes, pain is felt, such as blunt pain behind the eyes.
- Decreased vision in one eye. Most individuals experience at least a temporary decrease in viewing power, but degrees of decline may vary.
Significant decreased viewing power generally develops within hours or days, and improves in weeks and months. Loss of vision can be permanent in some cases.
- Decreased visibility. Decreased field of view can occur, with erratic patterns.
- Decreased color viewing power. Optic neuritis can affect color perception, and individuals who experience it can feel that the color does not appear as bright as before.
- Flashes of light. Some individuals with optic neuritis report experiencing flashes of light with eyeball movement.
Optic Neuritis Diagnosis
If there is a suspected optic neuritis, there are several examinations that are generally done, namely:
- Pupil reflex examination by illuminating both eyes using a flashlight.
- Visual examination to assess sharp vision.
- Funduscopy examination to assess retinal and nerve conditions. In 2/3 cases of optic neuritis, the results of funduscopy examination show a normal picture.
To ensure that the sufferer is optic neuritis and not other eye nerve abnormalities, a blood test is also required. The examination that needs to be done is in the form of sedimentation rate, C-reactive protein, thyroid hormone function, antinuclear antibody (ANA), and DNA examination.
Source:
- Image: Pratik Y. Gogri, Somen L. Misra, Raghunandan N. Kothari, Akshay J. Bhandari, Hitesh V. Gidwani, CC BY 4.0 https://creativecommons.org/licenses/by/4.0, via Wikimedia Commons
- Video: DrER.tv