Ī 2012 review could not find strong evidence for any single cause, although many theories have been discredited.
It is also associated with a high socioeconomic class and higher level of education. Risk factors include doing work that involves focusing on close objects, greater time spent indoors, urbanization, and a family history of the condition. The underlying cause is believed to be a combination of genetic and environmental factors. Onset is often in school children, with worsening between the ages of 8 and 15. Upon routine examination of the eyes, the vast majority of myopic eyes appear structurally identical to nonmyopic eyes. If the extent of the myopia is great enough, even standard reading distances can be affected. Near-sighted vision ( top/left), normal vision ( bottom/right)Ī near-sighted individual can see clearly out to a certain distance (the far point of the eye), but objects placed beyond this distance appear blurred. Uncorrected near-sightedness is one of the most common causes of vision impairment globally along with cataracts, macular degeneration, and vitamin A deficiency. In China the proportion of girls is slightly higher than boys. Among children, it affects 1% of rural Nepalese, 4% of South Africans, 12% of people in the US, and 37% in some large Chinese cities. Rates among adults are between 15% and 49%. Rates vary significantly in different areas of the world. Near-sightedness is the most common eye problem and is estimated to affect 1.5 billion people (22% of the world population). Surgeries like Implantable Collamer Lens (ICL) implant a lens inside the anterior chamber in front of the natural eye lens. Refractive surgeries like LASIK and PRK permanently change the shape of the cornea. Contact lenses can provide a relatively wider corrected field of vision, but are associated with an increased risk of infection. Eyeglasses are the simplest and safest method of correction. Near-sightedness can be corrected with eyeglasses, contact lenses, or by refractive surgery. This decrease in risk may be related to natural light exposure. Tentative evidence indicates that the risk of near-sightedness can be decreased by having young children spend more time outside. Myopia results from the length of the eyeball growing too long or less commonly the lens being too strong. Severe near-sightedness is associated with an increased risk of retinal detachment, cataracts, and glaucoma. Other symptoms may include headaches and eye strain. As a result, distant objects appear blurry while close objects appear normal. Near-sightedness, also known as myopia and short-sightedness, is an eye disease where light focuses in front of, instead of on, the retina. Near work, greater time spent indoors, family history Retinal detachment, cataracts, glaucoma Ĭombination of genetic and environmental factors Diagram showing changes in the eye with near-sightednessĭistant objects appear blurry, close objects appear normal, headaches, eye strain
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