Whether you have problems with your vision or not, there is a good chance you have basic knowledge of common eye conditions, including glaucoma, age-related macular degeneration (AMD), cataracts, and refractive errors, such as nearsightedness (myopia) and farsightedness (hyperopia). Besides these common conditions, however, there are many other diseases that affect the eye.

Here are three eye conditions you probably know nothing about.

Achromatopsia

This rare eye disease affects about 1 in 30,000 people throughout the world. Achromatopsia is a genetic condition in which a person can't see any color. People with this eye disease are usually only able to see black, white, and gray. Besides not having the ability to see color, those who have achromatopsia also have other issues with their vision including:

• Photophobia - sensitivity to light and glare
• Nystagmus - rapid and repetitive movements of the eye that occur involuntarily
• Low visual acuity - decreased clarity or sharpness of vision
• Farsightedness - objects appear blurry when nearby

Unfortunately for those who were born with achromatopsia, there is currently no treatment options available that can restore color to their vision.

Keratoconus

When the round cornea of the eye becomes thins and forms a bulge in the shape of a cone, it is called keratoconus. This rare eye condition affects one in 2,000 people. Some of the most common symptoms of this eye condition include:

• Blurred or distorted vision
• Double vision
• Sensitivity to light
• Inability to see very well in dim light

For those who have mild vision problems, treatment options for keratoconus including wearing eyeglasses. An optometrist might also prescribe custom-made specialty contact lenses. When the condition is more severe, some people with keratoconus may need surgery or a cornea transplant.

Neuromyelitis Optica

Also known as Devic's disease, Neuromyelitis Optica (NMO) is an autoimmune disorder in which the cells of the immune system attack and destroy cells located in the optic nerve and also the spinal cord.

This disorder affects only 4,000 people in the United States and 25 million throughout the world. It is more common for women than men to have this eye disease. Because it is also a disorder of the central nervous system, it is often misdiagnosed as multiple sclerosis.

Some of the symptoms include:

• Blindness in one or both eyes
• Pain in the eye
• Uncontrollable vomiting and hiccups
• Painful spasms throughout the body

There is no cure for NMO. However, it can be managed through the use of corticosteroid medication and plasma exchange. If you'd like to learn more about these and other eye disorders, contact an eye clinic like Vision Eyeland Super Optical LLC.