Myopia
Origin
New Latin, from Greek myōpia, from myōp-, myōps
Definitions
- 1: a condition in which the visual images come to a focus in front of the retina of the eye resulting especially in defective vision of distant objects
- 2: a lack of foresight or discernment : a narrow view of something
Description
Myopia (Greek: μυωπία, muōpia, from myein "to shut" – ops (gen. opos) "eye"), commonly known as being nearsighted (American English) and shortsighted (British English), is a condition of the eye where the light that comes in does not directly focus on the retina but in front of it. This causes the image that one sees when looking at a distant object to be out of focus, but in focus when looking at a close object.
Eye care professionals most commonly correct myopia through the use of corrective lenses, such as glasses or contact lenses. It may also be corrected by refractive surgery, though there are cases of associated side effects. The corrective lenses have a negative optical power (i.e. have a net concave effect) which compensates for the excessive positive diopters of the myopic eye.
The global prevalence of refractive errors has been estimated from 800 million to 2.3 billion. The incidence of myopia within sampled population often varies with age, country, sex, race, ethnicity, occupation, environment, and other factors. Variability in testing and data collection methods makes comparisons of prevalence and progression difficult.
The prevalence of myopia has been reported as high as 70–90% in some Asian countries, 30–40% in Europe and the United States, and 10–20% in Africa. Myopia is less common in African people and associated diaspora. In Americans between the ages of 12 and 54, myopia has been found to affect African Americans less than Caucasians.
As a Metaphor
The terms "myopia" and "myopic" (or the common terms "shortsightedness" or "shortsighted", respectively) have been used metaphorically to refer to cognitive thinking and decision making that is narrow in scope or lacking in foresight or in concern for wider interests or for longer-term consequences. It is often used to describe a decision that may be beneficial in the present, but detrimental in the future, or a viewpoint that fails to consider anything outside a very narrow and limited range. Hyperopia, the biological opposite of myopia, may also be used metaphorically for a value system or motivation that exhibits "farsighted" or possibly visionary thinking and behavior; that is, emphasizing long-term interests at the apparent expense of near-term benefit.
