Hyperopia

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Template:DiseaseDisorder infobox | }} Hyperopia, also known as hypermetropia or colloquially as farsightedness or longsightedness, is a defect of vision caused by an imperfection in the eye (often when the eyeball is too short or when the lens cannot become round enough), causing inability to focus on near objects, and in extreme cases causing a sufferer to be unable to focus on objects at any distance. As an object moves towards the eye, the eye must increase its power to keep the image on the retina. If the power of the cornea and lens is insufficient, as in hypermetropia, the image will appear blurred. Image:Hypermetropia.png

People with hyperopia may experience blurred vision, asthenopia, accommodative dysfunction, binocular dysfunction, amblyopia, and strabismus<ref>American Optometric Association. Optometric Clinical Practice Guideline: Care of the patient with hyperopia. 1997.</ref>.

Contents 1 Classification of hyperopia 1.1 Classification by clinical appearance 1.2 Classification by severity 1.3 Classification by accommodative status 2 Prevalence 3 Treatment 4 Notes 5 See also

Classification of hyperopia

Hyperopia is typically classified according to its clinical appearance, its severity, or how it relates to the eye's accommodative status<ref>American Optometric Association. Optometric Clinical Practice Guideline: Care of the patient with hyperopia. 1997.</ref>.

Classification by clinical appearance

• Simple hyperopia
• Pathological hyperopia
• Functional hyperopia

Classification by severity

Hyperopia is often categorized by the amount of refractive error<ref>Augsburger AR. "Hyperopia." In: Amos JF, ed. Diagnosis and management in vision care. Boston: Butterworths, 1987:1010-19.</ref>:

• Low hyperopia is a refractive error of +2.00 diopters (D) or less.
• Moderate hyperopia is a refractive error from +2.25 to +5.00 D.
• High hyperopia is a refractive error of +5.25 D or more.

Classification by accommodative status

• Facultative hyperopia
• Absolute hyperopia
• Manifest hyperopia
• Latent hyperopia

Prevalence

An American study published in Archives of Ophthalmology found that nearly 1 in 8 (12.8%) children between the ages of 5 and 17 has hyperopia<ref>Kleinstein RN, Jones LA, Hullett S, Kwon S, Lee RJ, Friedman NE, Manny RE, Mutti DO, Yu JA, Zadnik K; Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error Study Group. "Refractive Error and Ethnicity in Children". Arch Ophthalmol. 2003 Aug;121(8):1141-7. PMID 12912692.</ref>, and a recent Polish study found that 1 in 5 (21%) students between the age of 6 and 18 was hyperopic<ref>Czepita D, Goslawski W, Mojsa A. "[Occurrence of hyperopia among students ranging from 6 to 18 years of age]." Klin Oczna. 2005;107(1-3):96-9. PMID 16052814.</ref>. A recent Australian study found that nearly 4 in 10 (38.4%) children between the ages of 4 and 12 were hyperopic <ref>Junghans BM, Crewther SG. "Little evidence for an epidemic of myopia in Australian primary school children over the last 30 years." BMC Ophthalmol. 2005 Feb 11;5(1):1. PMID 15705207</ref>. A recent Brazilian study, however, found that nearly 7 in 10 (71%) of the students in one city were hyperopic<ref>Garcia CA, Orefice F, Nobre GF, Souza Dde B, Rocha ML, Vianna RN. "[ Prevalence of refractive errors in students in Northeastern Brazil. ]" Arq Bras Oftalmol. 2005 May-Jun;68(3):321-5. Epub 2005 Jul 26. PMID 16059562</ref>. A study of Jordanian adults aged 17 to 40 found only 1 in 20 (5.7%) were hyperopic<ref>Mallen EA, Gammoh Y, Al-Bdour M, Sayegh FN. "Refractive error and ocular biometry in Jordanian adults." Ophthalmic Physiol Opt. 2005 Jul;25(4):302-9. PMID 15953114.</ref>. A recent study involving first-year undergraduate students in the United Kingdom found that 18.8% of British whites and 17.3% of British Asians were hyperopic<ref>Logan NS, Davies LN, Mallen EA, Gilmartin B. "Ametropia and ocular biometry in a U.K. university student population." Optom Vis Sci. 2005 Apr;82(4):261-6. PMID 15829853.</ref>.

Treatment

Minor amounts of hyperopia are sometimes left uncorrected, however, larger amounts may be corrected with convex lenses in eyeglasses or contact lenses. Hyperopia is sometimes correctable with various refractive surgery procedures.

Notes

See also

• Astigmatism (eye)
• Eye examination
• Eye
• Eyeglass prescription
• Lens (optics)
• Myopia
• Ophthalmology
• Optician
• Optometry
• Presbyopia
• Refraction errorTemplate:Eye-stub

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