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Eye Health Glossary


Enucleation: A procedure in which the eye is removed.

Hyperopia: A condition in which a person has difficulty seeing objects up close, but objects further away are seen clearly. Hyperopia is commonly referred to as farsightedness.

Intraocular: Of or related to the inside of the eye.

Iris: The colored membrane of the eye, surrounding the pupil. The iris controls the amount of light entering the pupil by expanding and contracting.

Iritis: The most common form of uveitis, it affects the iris and is often associated with autoimmune disorders such as arthritis. Iritis may develop suddenly and may last up to eight weeks, even with treatment.

Legal blindness: Having visual acuity that, in both eyes, can't be corrected to better than 20/200 or has a visual field of 20 degrees or less (tunnel vision) remaining.

Low vision: A condition in which a person is either legally blind (visual acuity of less than 20/200 or tunnel vision) or visual acuity between 20/70 and 20/200 despite the use of conventional corrections such as prescription eyeglasses.

Macula: The central portion of the retina, a healthy macula is critical in maintaining sharp vision.

Macular edema: A swelling of the macula that can cause vision to become blurred or impaired. It is usually caused by an injury or disease.

Myopia: A condition in which a person has difficulty seeing objects in the distance. Myopia is commonly referred to as nearsightedness.

Night blindness: A condition in which a person has impaired vision in dim or darkened conditions. Night blindness is commonly caused by a deficiency in vitamin A or, less commonly, by retinitis pigmentosa.

Nyctalopia: See night blindness.

Ocular: Of or relating to the eye.

Ophthalmologist: Ophthalmologists are doctors who specialize in the medical and surgical care of the eyes and visual system and also the prevention of eye disease and injury. They can be either doctors of medicine (MD) that graduate from a medical school or doctors of osteopathy (DO) who graduate from osteopathy school. As a qualified specialist, an ophthalmologist is qualified to deliver total eye care, meaning vision services, eye exams, medical and surgical eye care, diagnosis and treatment of disease, and management of visual complications that are caused by other conditions, like diabetes.

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