A cataract is a clouding of the eye's natural lens. When looking at something, light must travel through the lens and focus onto the retina, a layer of light-sensitive cells at the back of the eye which functions as film for an older camera (captures light). A clear lens focuses light properly onto the retina. When cloudy, all of the light does not make it to the retina, resulting in blurred vision. How quickly cataracts develop depends on the individual.
Glaucoma is an eye disease associated with elevated intraocular pressure (IOP) inside the eye that damages the optic nerve, resulting in vision loss. It is a chronic disease that usually has no symptoms and may damage your optic nerve before you notice actual changes in your vision. Three million Americans suffer from glaucoma but only half know they have it.
Macular degeneration is condition in which the center of the inner lining of the eye, known as the macula area of the retina, suffers gradual thinning, atrophy, and in some cases, bleeding. This can result in loss of central vision, affecting your ability to read, drive, and see clearly straight ahead.
Diabetic retinopathy, a condition caused by diabetes, occurs when the blood vessels in the back of the eye change, leading to a significant loss of vision. It is one of the most frequent causes of retinal blindness in the world.
Retinal detachment is disorder of the eye in which the retina peels away from its underlying layer of support tissue. Initial detachment may be localized, but without rapid treatment the entire retina may detach, leading to vision loss and blindness. Retinal detachment is considered a medical emergency.