Hyperopia

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Original article contributed by: Nathan Carpenter, A. Paula Grigorian, MD
All contributors: A. Paula Grigorian, MD
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Review: Assigned status Up to Date by A. Paula Grigorian, MD on January 6, 2015.
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Hyperopia is also known as “farsightedness” or “hypermetropia”. It is an ocular condition in which the refracting power of the eye causes light rays entering the eye to have a focal point that is posterior to the retina while accommodation is maintained in a state of relaxation. Visual acuity is better at far (e.g. 6 meters) distances than at near (e.g. 0.33 meters) distances[1]


Disease[edit | edit source]

Significant hyperopia is defined as any degree of hyperopia sufficient to cause symptoms prompting clinical attention.[1] Hyperopia may be classified by structure and/or function of the eye. Simple hyperopia is due to decreased axial length or decreased converging power of cornea, lens, and/or media (flattened cornea/decreased curvature, increased thickness of lens, etc.).[1] Pathologic hyperopia is due to atypical development, trauma, or disease of the eye (i.e. cataract, microphthalmia, nanophthalmia, aniridia, etc.).[1],[2] Functional hyperopia is due to paralysis of accommodation.[1],[3] If affected, functional hyperopia is usually present at birth. Drugs, such as cycloplegics, can also cause a transient hyperopia.[1]

Hyperopia may also be categorized by the degree of refractive error: Low hyperopia is +2.00D or less, Moderate hyperopia ranges from +2.25 to +5.00D, and High hyperopia is +5.25D or more. High hyperopia may be associated with blurring of the optic disk margin, known as pseudopapilledema. It can be differentiated from true papilledema by the presence of normal caliber vasculature and normal appearing juxtaposed retina.[1]

Hyperopia may also be classified by the role of accommodation to visual functioning. Facultative hyperopia is hyperopia that can be overcome by accommodation whereas Absolute hyperopia cannot be overcome by accommodation. Total hyperopia is the sum of Facultative and Absolute hyperopia.[1]

Hyperopia may also be categorized based upon the outcome of noncycloplegic and cycloplegic refractions. Manifest hyperopia is determined with noncycloplegic refraction whereas Latent hyperopia is determined with cycloplegic refraction. The magnitude of hyperopia is the sum of Manifest and Latent hyperopia.[1]

Epidemiology[edit | edit source]

Physiologic (Simple and Functional) hyperopia is much more common than pathologic hyperopia.[1] Decreased axial length is the most common etiology for hyperopia. Overall prevalence of hyperopia is around 10%, approximately 14 million people, in the United States.[4],[5] Most full-term infants are mildly hyperopic. By age 6-9 months approximately 4-9% of infants are hyperopic and by age 12 months the prevalence is approximately 3.6%. Infants with moderate to high hyperopia (greater than +3.50D) are up to 13 times more likely to develop strabismus by age 4 if left uncorrected.[1] Prevalence is 13% at age 6 and 5% at age 12 in Australia.[6] Prevalence of hyperopia at age 40 and above is 9.9% in 2010 in the United States.[7] Prevalence of hyperopia is higher relative to myopia between ages 45-65.[4]

The Mutli-Ethnic Pediatric Eye Disease Study Group reports hyperopia prevalence of children in each ethnic group of the sample population as being 26.9% of Hispanics, 25% of non-Hispanic White Americans, 20.8% of African Americans, and 13% of Asian Americans.[8],[9] Hyperopia is most common in the Hispanic population, next most common in Native Americans, African Americans, and Pacific Islanders, and least most common in Asians and Caucasians, according to a multi-ethnic study of atherosclerosis.[10]

There is no known gender difference in the prevalence of hyperopia. Family history increases risk of hyperopia.[1] Hyperopia is associated with maternal smoking during pregnancy, prematurity, and low birth weight.[11] Hyperopia is associated with lower literacy standards in children.[12] In the United Kingdom it was reported that intelligence quotient scores are lower in hyperopic patients than in myopic patients.[13] Living in a rural area rather than an urban area is associated with higher prevalence of hyperopia.[14] Hyperopia may also be associated with diabetes mellitus.[1]

Presentation[edit | edit source]

Most commonly, the patient may experience decreased visual acuity or squinting at near distances. Strabismus, which is most commonly recognized in childhood, can be a sign of a concomitant hyperopia. Anisometropia may also be noted on visual acuity exam or red reflex testing. Accommodation typically enables younger patients to overcome facultative and latent hyperopia.[1] Asthenopia (eye strain) and/or eye pain is commonly reported and is commonly associated with headaches due to close work such as reading, writing, or computer work.[1] Accommodative dysfunction may result as the eye is no longer capable of accommodating to focus light onto the retina.[2] Binocular dysfunction may also be a symptom of hyperopia.[1]

Pathophysiology[edit | edit source]

Light rays and light particles entering the eye are converged at a point posterior to the retina while accommodation is maintained in a state of relaxation.[1] The magnitude of hyperopia is determined by the diopteric power of converging lenses required to advance the focal point of light onto the retinal plane.[2]

Primary prevention[edit | edit source]

unavailable

Diagnosis[edit | edit source]

Visual acuity screening is recommended to detect hyperopia as well as other eye conditions. The gold standard for visual acuity testing is to use the Snellen chart using manifest and cycloplegic refraction. The difference between Cycloplegic hyperopia and Manifest (Noncycloplegic) hyperopia is Latent hyperopia.[1]

Subjective refraction can be performed with a visual acuity chart at far distance (20ft or 6m) and near distance (1ft or 0.33m).[1] These screenings typically are performed by teachers, primary care physicians (e.g. pediatricians, family physicians, etc.), optometrists, and/or ophthalmologists.[1] The charts used for visual acuity screening include, but are not limited to, Snellen, Allen, HOTV, Tumbling E, etc.

Objective refraction can be performed using an autorefraction machine or retinocopy.[1] This first uses [3]rays to measure at what distance an object is focused on the retina.[1] Retinoscopy is the method preferred in babies and children.[1],[3]
It requires a cycloplegic, retinoscope, and a series of lenses or a phoropter to determine when light rays are focused onto the retinal plane. The tester neutralizes the movement of the reflected light with one of the lenses in the series.[1]

Differential diagnosis[edit | edit source]

Orbital tumors, serous elevation of the retina, posterior scleritis, presbyopia, hypoglycemia, cataracts, and/or post refractive surgery may present in a similar fashion to hyperopia.[15]

Management[edit | edit source]

The standard, and safest, treatment for symptomatic hyperopia is corrective lenses. Mild hyperopia does not need treatment. Hyperopic correction can be achieved by glasses lenses, contact lenses, or refractive surgery.[1] The lenses required to correct hyperopia are convex lenses that converge light rays entering the eye to bring the focal point of the eye onto the retina.[1][2] Glasses lenses are tolerated better in babies and children.[1] Contact lenses are typically not preferred until adolescence or later, however the decision is based on the responsibility level of the patient or caregiver.[1] A survey of practitioners revealed a common threshold for treatment intervention of hyperopia was 3.00D to 5.00D of asymptomatic hyperopia in children at age [2]

Refractive surgery is typically not preferred until the refractive error of the eye has stabilized and growth of the eye has stopped, which typically occurs in the third decade of life.[3] Surgical options for hyperopia include thermal laser keratoplasty (TLK), conductive keratoplasty (CK), spiral hexagonal keratotomy, excimer laser, clear lens extraction with intraocular lens implantation or phakic intraocular lens implantation.[16] 

Prognosis[edit | edit source]

Young children (ages 0-10) with uncomplicated low-to-moderate hyperopia usually do not require intervention. With aging, loss of accommodation causes visual acuity to decrease and hyperopia to worsen. Decreased quality of life is common with hyperopia.[1] There may also be a decrease in the ability to learn and develop within normal limits when vision is poor.[1] Hyperopia that is not fully compensated with accommodation will force the eye into convergence and an esotropia (crossed eyes) will develop.[5]

Amblyopia can be another complication of hyperopia.[1] Monocular amblyopia or Binocular amblyopia may result.[2] Levels greater than 1.00D of hyperopic anisometropia and 5.00D of isometric hyperopia are considered amblyogenic.[1] Accommodative esotropia, acute angle closure glaucoma, and strabismus may also result from hyperopia.

Additional Resources[edit | edit source]

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References[edit | edit source]

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 1.23 1.24 1.25 1.26 1.27 1.28 1.29 1.30 1.31 Moore BD, Augsburger AR, Ciner EB, Cockrell DA, Fern KD, Harb E. Optometric Clinical Practice Guideline: Care of the Patient with Hyperopia. St. Louis, MO: American Optometric Association; 1997:1-29
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Riordan-Eva P. Chapter 21. Optics & Refraction. In: Riordan-Eva P, Cunningham, Jr. ET, eds. Vaughan & Asbury's General Ophthalmology. 18th ed. New York, NY: McGraw-Hill; 2011:396-411.
  3. 3.0 3.1 3.2 3.3 Bartley GB, Liesegang TJ. Essentials of Ophthalmology. Philadelphia, PA: JB Lippincott Company; 1992:227-240.
  4. 4.0 4.1 Bope ET, Kellerman RD. Conn’s Current Therapy. Philadelphia, PA: Saunders; 2013:323-326
  5. 5.0 5.1 Trobe JD. The Physician’s Guide to Eye Care. San Francisco, CA: American Academy of Ophthalmology; 2006:145-149.
  6. Ip JM, Robaei D, Kifley A, Wang JJ, Rose KA, Mitchell P. Prevalence of hyperopia and associations with eye findings in 6 and 12 year olds. Ophthalmology. 2008: 115(4):678-685
  7. Kempen JH, Mitchell P, Lee KE, et al. The Prevalence of refractive errors among adults in the United States, Western Europe, and Australia. Archives of Ophthalmology. 2005: 122(4):495-505.
  8. Multi-Ethnic Pediatric Eye Disease Study Group. Prevalence of myopia and hyperopia in 6- to 72-month-old African American and Hispanic children: the multiethnic pediatric eye disease study. Ophthalmology. 2010: 117(1):140-147.
  9. Wen G, Tarczy-Hornoch K, McKean-Cowdin R, et al. Prevalence of myopia, hyperopia, and astigmatism in non-Hispanic white and asian children: multiethnic pediatric eye disease study. Ophthalmology. 2013: 120(10):2109-2116.
  10. Pan CW, Klein BE, Cotch MF, et al. Racial variations in the prevalence of refractive errors in the United States: the multi-ethnic study of atherosclerosis. American Journal of Ophthalmology. 2013: 155(6):1129-1138.
  11. Borchert MS, Varma R, Cotter SA, et al. Risk Factors for Hyperopia and Myopia in Preschool Children: The Multi-Ethnic Pediatric Eye Disease and Baltimore Pediatric Eye Disease Studies. Ophthalmology. 2011: 118(10):1966-1973.
  12. Williams WR, Latif AH, Hannington L, Watkins DR. Hyperopia and educational attainment in a primary school cohort. Archives of Disease in Childhood. 2005: 90(2):150-153.
  13. Williams C, Miller LL, Gazzard G, Saw SM. A comparison of measures of reading and intelligence as risk factors for the development of myopia in UK cohort of children. British Journal of Ophthalmology. 2008: 92(8):1117-1121.
  14. Padhye AS, Khandekar R, Dharmadhikari S, Dole K, Gogate P, Deshpande M. Prevalence of uncorrected refractive error and other eye problems among urban and rural school children. Middle East African Journal of Ophthalmology. 2009: 16(2):69-74.
  15. Ehlers JP, Shah CP, Fenton GL, Hoskins EN. Chapter 02: Differential Diagnosis of Ocular Signs. The Wills Eye Manual: Office and Emergency Room Diagnosis and Treatment of Eye Disease. Philadelphia: Lippincott Williams & Wilkins; 2008:10
  16. Yanoff M, Duker JS. Ophthalmology. Edinburgh, Scotland. Mosby Elsevier. 2009:61-63.