Optic Nerve Damage

Optic nerve, also known as cranial nerve, is a part of central nervous system. It carries visual information from the retina to the brain. Optic nerves are present in the optic discs behind the eyes. A viral or bacterial infection can lead to pain behind the eye, which usually indicates inflammation of optic nerve. The condition wherein the optic nerve is inflamed is called 'optic neuritis'; which if not treated promptly can lead to loss of vision.

Damaged Optic Nerve

Causes
The optic nerve gets damaged due to some inherited diseases, eye problems like glaucoma, development of tumors, inflammation, and severe bacterial and viral infections. Multiple sclerosis can affect the function of the nerves. Inflammation of the spinal cord and optic nerve is known as neuromyelitis optica. It is an autoimmune disorder and it can affect the function of the nerves seriously. Inflamed arteries in the skull, cat scratch fever, tuberculosis, bee stings, lupus, lyme disease, hepatitis B, herpes, swelling of the optic disc (papilla) due to an increase in intracranial pressure, other common diseases like diabetes, pernicious anemia and hyperthyroidism, direct trauma to the optic nerve, nutritional deficiencies, exposure to toxins like lead, methyl alcohol, quinine, and arsenic can also result in damaged optic nerve. Excessive consumption of alcohol or tobacco, blocked or limited blood flow to the eyes, meningitis, sinusitis, encephalitis may destroy the protective nerve coverings and affect the nerve function. Recognizing the symptoms of optic nerve damage at an early stage, and contacting an eye specialist help prevent total blindness.

Symptoms

• Eyeball pain
• Blurred vision
• Eye pain that is worsened by eye movement
• Abnormal side vision because of limited mobility of the pupil
• Distorted vision
• Loss of contrasts, things may appear brighter in one eye than in the other
• Reduced color vision
• Failure in interpreting the surroundings
• Dizziness
• Severity of loss of vision may vary from patient to patient. It may vary according to which part of the nerve is damaged and how much it is damaged. Some may experience blurring while some may experience complete blindness.

In case of optic neuritis, vision loss is usually temporary (sometimes, it can be permanent also). Some people experience gradual loss of peripheral vision. Some may experience loss of vision within a day or a week. The severity of the damage, in case of optical neuritis, may be increased by heat or exercise. Mostly, patients diagnosed with optical nerve damage experience permanent vision loss. Reversing optic nerve damage or vision correction is very difficult.

Treatment
In case of optical nerve damage, no visible changes around the eyes are usually noticed, but in some patients, swelling or enlargement of the blood vessels around the nerve can be seen. If any of the above symptoms are noticed, one should immediately contact an ophthalmologist. It is a fact that cells that form the optic nerve are unable to regenerate, or they cannot repair themselves. Therefore optic nerve damage from glaucoma and other diseases or trauma is irreversible. The damage often results in permanent loss of vision. Scientists are researching on how optic nerve regeneration can be promoted. Studies regarding 'neural stem cell therapy' show that such therapy can prove to be beneficial for restoration of sight after optic nerve injury, in the future.

Eyes are delicate organs. Loss of vision can make your life miserable. Proper eye care is essential to prevent eye infections and eye disorders. We have already seen that blurred vision causes are innumerable. Early diagnosis and prompt treatment of eye problems help prevent damage to the optic nerve. For any type of eye problem, you should immediately contact an ophthalmologist.