Error Refraction Eye
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Tools Español You Are Here: Home → Health Topics → Refractive Errors URL of this page: https://medlineplus.gov/refractiveerrors.html Refractive Errors Also called: Farsightedness, Hyperopia, Myopia, Nearsightedness To use the sharing features types refractive errors on this page, please enable JavaScript. On this page Basics Summary Start Here refractive error treatment Latest News Diagnosis and Tests Prevention and Risk Factors Treatments and Therapies Learn More Related Issues Specifics Genetics See, refractive errors ppt Play and Learn Images Research Statistics and Research Clinical Trials Journal Articles Resources Reference Desk Find an Expert For You Children Patient Handouts Summary The cornea and lens of your eye refractive errors pdf helps you focus. Refractive errors are vision problems that happen when the shape of the eye keeps you from focusing well. The cause could be the length of the eyeball (longer or shorter), changes in the shape of the cornea, or aging of the lens. Four common refractive errors are Myopia, or nearsightedness - clear vision close up but blurry in the distance
Refractive Error In Children
Hyperopia, or farsightedness - clear vision in the distance but blurry close up Presbyopia - inability to focus close up as a result of aging Astigmatism - focus problems caused by the cornea The most common symptom is blurred vision. Other symptoms may include double vision, haziness, glare or halos around bright lights, squinting, headaches, or eye strain. Glasses or contact lenses can usually correct refractive errors. Laser eye surgery may also be a possibility. NIH: National Eye Institute Start Here Facts about Astigmatism (National Eye Institute) Also in Spanish Facts about Hyperopia (National Eye Institute) Also in Spanish Facts about Myopia (National Eye Institute) Also in Spanish Facts about Presbyopia (National Eye Institute) Facts about Refractive Errors (National Eye Institute) Also in Spanish Refractive Errors (American Association for Pediatric Ophthalmology and Strabismus) Also in Spanish Latest News Undiagnosed Eye Problems Pose Risks for Migrant Farm Workers (10/10/2016, HealthDay) Diagnosis and Tests Dilating Eye Drops (American Association for Pediatric Ophthalmology and Strabismus) Also in Spanish Near Vision Test for Adults (Prevent Blindness America) Retinoscopy (American Association for Pediatric Ophthalmology and Strabismus) Also in Spanish Prevention and Risk Factor
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Refractive Error Correction
by Jill E. Bixler, M.D. On this page: What Is a Refractive Error? Symptoms Causes refractive errors of the human eye Risk Factors Tests and Diagnosis Treatment and Drugs Clinic Information What Is a Refractive Error? Refractive error means that the shape of your refractive error measurement eye does not bend light correctly, resulting in a blurred image. The main types of refractive errors are myopia (nearsightedness), hyperopia (farsightedness), presbyopia (loss of near vision with age), and astigmatism. Symptoms Blurred vision Difficulty reading or https://medlineplus.gov/refractiveerrors.html seeing up close Crossing of the eyes in children (esotropia) Causes Overuse of the eyes does not cause or worsen refractive error. The causes of the main types of refractive error are described below: Myopia(close objects are clear, and distant objects are blurry) Also known as nearsightedness, myopia is usually inherited and often discovered in childhood. Myopia often progresses throughout the teenage years when the body is growing rapidly. Watch a video explaining myopia. Hyperopia http://kellogg.umich.edu/patientcare/conditions/refractive.errors.html (close objects are more blurry than distant objects) Also known as farsightedness, hyperopia can also be inherited. Children often have hyperopia, which may lessen in adulthood. In mild hyperopia, distance vision is clear while near vision is blurry. In more advanced hyperopia, vision can be blurred at all distances. Watch a video explaining hyperopia. Presbyopia (aging of the lens in the eye) After age 40, the lens of the eye becomes more rigid and does not flex as easily. As a result, the eye loses its focusing ability and it becomes more difficult to read at close range. This normal aging process of the lens can also be combined with myopia, hyperopia or astigmatism. Watch a video explaining presbyopia. Astigmatism Astigmatism usually occurs when the front surface of the eye, the cornea, has an asymmetric curvature. Normally the cornea is smooth and equally curved in all directions, and light entering the cornea is focused equally on all planes, or in all directions. In astigmatism, the front surface of the cornea is curved more in one direction than in another. This abnormality may result in vision that is much like looking into a distorted, wavy mirror. Usually, astigmatism causes blurred vision at all distances. Watch a video explaining astigmatism. Risk Factors People with high degrees of myopia have a higher risk of retinal detachment w
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