Editing Myopia (section)

==Diagnosis==
A diagnosis of myopia is typically made by an [[eye care professional]], usually an [[Optometry|optometrist]] or [[Ophthalmology|ophthalmologist]]. This is by [[Refraction|refracting]] the [[eye]] with the use of [[Cycloplegia|cycloplegics]] such as [[atropine]] with responses recorded when [[Accommodation (vertebrate eye)|accommodation]] is relaxed.<ref name=":4" /> Diagnosis of progressive myopia requires regular [[eye examination]] using the same method.<ref name=":4" />

===Types===
Myopia can be classified into two major types; [[Anatomy|anatomical]] and clinical. The types of myopia based on anatomical features are axial, curvature, index and displacement of refractive element. [[Birth defect|Congenital]], simple and pathological myopia are the clinical types of myopia.<ref name=":6" />

Various forms of myopia have been described by their clinical appearance:<ref name="Duke-Elder" /><ref name="Goss">{{cite book| vauthors = Goss DA, Eskridge JB |chapter=Myopia| veditors = Amos JB |title=Diagnosis and management in vision care|publisher=Butterworths|location=Boston|year=1988|isbn=978-0-409-95082-3|page=445|oclc=14967262}}</ref><ref name="Richards1976">{{cite journal | vauthors = Richards OW | title = Instrument myopia--microscopy | journal = American Journal of Optometry and Physiological Optics | volume = 53 | issue = 10 | pages = 658–63 | date = October 1976 | pmid = 1015520 | doi = 10.1097/00006324-197610000-00003 | s2cid = 37513722 }}</ref>
* Simple myopia: Myopia in an otherwise normal eye, typically less than 4.00 to 6.00 [[Dioptre|diopters]].<ref name="AOA">{{cite report|author=American Optometric Association|year=1997|title=Optometric Clinical Practice Guideline: Care of the Patient with Myopia|url=http://www.aoa.org/documents/optometrists/CPG-15.pdf|url-status=dead|archive-url=https://web.archive.org/web/20150122062311/http://www.aoa.org/documents/optometrists/CPG-15.pdf|archive-date=22 January 2015|df=dmy-all|access-date=17 February 2015}}</ref> This is the most common form of myopia.
* Degenerative myopia, also known as malignant, pathological, or progressive myopia, is characterized by marked [[Fundus (eye)|fundus]] changes, such as posterior [[staphyloma]], and associated with a high [[refractive error]] and subnormal visual acuity after correction.<ref name="Cline" /> This form of myopia gets progressively worse over time. Degenerative myopia has been reported as one of the main causes of [[visual impairment]].<ref name="pmid12022735">{{cite journal | vauthors = Li CY, Lin KK, Lin YC, Lee JS | title = Low vision and methods of rehabilitation: a comparison between the past and present | journal = Chang Gung Medical Journal | volume = 25 | issue = 3 | pages = 153–61 | date = March 2002 | pmid = 12022735 }}</ref>
* [[Pseudomyopia]] is the blurring of distance vision brought about by [[spasm]] of the [[Accommodation (eye)|accommodation]] system.<ref name="Cassin">Cassin, B. and Solomon, S. (2001) ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company. {{ISBN|0937404632}}.</ref>
* Nocturnal myopia: Without adequate stimulus for accurate accommodation, the accommodation system partially engages, pushing distance objects out of focus.<ref name="AOA" />
* Nearwork-induced transient myopia (NITM): short-term myopic far point shift immediately following a sustained near visual task.<ref name="Ong">{{cite journal | vauthors = Ong E, Ciuffreda KJ | title = Nearwork-induced transient myopia: a critical review | journal = Documenta Ophthalmologica. Advances in Ophthalmology | volume = 91 | issue = 1 | pages = 57–85 | year = 1995 | pmid = 8861637 | doi = 10.1007/BF01204624 | s2cid = 2065074 }}</ref> Some authors argue for a link between NITM and the development of permanent myopia.<ref name="Ciuffreda">{{cite journal | vauthors = Ciuffreda KJ, Vasudevan B | title = Nearwork-induced transient myopia (NITM) and permanent myopia—is there a link? | journal = Ophthalmic & Physiological Optics | volume = 28 | issue = 2 | pages = 103–14 | date = March 2008 | pmid = 18339041 | doi = 10.1111/j.1475-1313.2008.00550.x | s2cid = 28700508 | doi-access = free }}</ref>
* [[Instrument myopia]]: over-accommodation when looking into an instrument such as a [[microscope]].<ref name="Richards1976" />
* Induced myopia, also known as acquired myopia, sometimes {{visible anchor|reversible myopic shift}}, results from various medications, increases in [[glucose]] levels, [[nuclear sclerosis]], [[oxygen toxicity]] (e.g., from [[underwater diving]] or from oxygen and [[hyperbaric therapy]]) or other anomalous conditions.<ref name="Bennett and Cooper 2022" >{{cite journal |url=https://www.ncbi.nlm.nih.gov/books/NBK470454/ |title=Hyperbaric Cataracts |first1=Michael H.  |last1=Bennett |first2=Jeffrey S. |last2=Cooper  |website=www.ncbi.nlm.nih.gov |publisher=StatPearls Publishing LLC. |pmid=29261974 |date=21 June 2022 |access-date=30 July 2022}}</ref><ref name="AOA" /> [[Sulfonamide (medicine)|Sulphonamide]] therapy can cause ciliary body edema, resulting in [[anterior]] displacement of the lens, pushing the eye out of focus.<ref name="Panday2007">{{cite journal | vauthors = Panday VA, Rhee DJ | title = Review of sulfonamide-induced acute myopia and acute bilateral angle-closure glaucoma | journal = Comprehensive Ophthalmology Update | volume = 8 | issue = 5 | pages = 271–6 | date = September 2007 | pmid = 18201514 | type = Review }}</ref> Elevation of [[Blood sugar level|blood-glucose]] levels can also cause edema (swelling) of the [[Lens (anatomy)|crystalline lens]] as a result of [[sorbitol]] accumulating in the lens. This edema often causes temporary myopia. [[Scleral buckle]]s, used in the repair of [[retinal detachment]]s may induce myopia by increasing the axial length of the eye.<ref>{{cite journal |last1=Vukojević |first1=Nenad |last2=Šikić |first2=Jakov |last3=Ćurković |first3=Tihomir |last4=Juratovac |first4=Zlatko |last5=Katušić |first5=Damir |last6=Šarić |first6=Borna |last7=Jukić |first7=Tomislav |title=Axial Eye Length after Retinal Detachment Surgery |journal=Collegium Antropologicum |date=20 June 2005 |volume=29 – Supplement 1 |issue=1 |pages=25–27 |pmid=16193671 |url=https://hrcak.srce.hr/27915 }}</ref>
* Index myopia is attributed to variation in the index of refraction of one or more of the ocular media.<ref name="Cline" /> Cataracts may lead to index myopia.<ref>{{cite journal | vauthors = Metge P, Donnadieu M | title = Myopie et cataracte |trans-title=Myopia and cataract | language = fr | journal = La Revue du Praticien | volume = 43 | issue = 14 | pages = 1784–6 | date = September 1993 | pmid = 8310218 |oclc=116851621 }}</ref>
* Form deprivation myopia occurs when the eyesight is deprived by limited illumination and vision range,<ref name="Young FA">{{cite journal | vauthors = Young FA | title = The effect of nearwork illumination level on monkey refraction | journal = American Journal of Optometry & Archives of American Academy of Optometry | volume = 39 | issue = 2 | pages = 60–7 | date = February 1962 | pmid = 14009334 | doi = 10.1097/00006324-196202000-00002 }}</ref> or the eye is modified with artificial lenses<ref name="Zhu et al.">{{cite journal | vauthors = Zhu X, Park TW, Winawer J, Wallman J | title = In a matter of minutes, the eye can know which way to grow | journal = Investigative Ophthalmology & Visual Science | volume = 46 | issue = 7 | pages = 2238–41 | date = July 2005 | pmid = 15980206 | doi = 10.1167/iovs.04-0956 | doi-access = free }}</ref> or deprived of clear form vision.<ref name="Wallman et al.">{{cite journal | vauthors = Wallman J, Gottlieb MD, Rajaram V, Fugate-Wentzek LA | title = Local retinal regions control local eye growth and myopia | journal = Science | volume = 237 | issue = 4810 | pages = 73–7 | date = July 1987 | pmid = 3603011 | doi = 10.1126/science.3603011 | bibcode = 1987Sci...237...73W | jstor = 1699607 | s2cid = 31790023 }}</ref> In lower vertebrates, this kind of myopia seems to be reversible within short periods of time. Myopia is often induced this way in various animal models to study the [[pathogenesis]] and mechanism of myopia development.<ref name="shen">{{cite journal | vauthors = Shen W, Vijayan M, Sivak JG | title = Inducing form-deprivation myopia in fish | journal = Investigative Ophthalmology & Visual Science | volume = 46 | issue = 5 | pages = 1797–803 | date = May 2005 | pmid = 15851585 | doi = 10.1167/iovs.04-1318 | doi-access = free }}</ref>

===Degree===
The degree of myopia is described in terms of the [[optical power|power]] of the ideal [[corrective lens|correction]], which is measured in [[Dioptre|diopters]]:<ref name="Grosvenor">{{cite journal | vauthors = Grosvenor T | title = A review and a suggested classification system for myopia on the basis of age-related prevalence and age of onset | journal = American Journal of Optometry and Physiological Optics | volume = 64 | issue = 7 | pages = 545–54 | date = July 1987 | pmid = 3307441 | doi = 10.1097/00006324-198707000-00012 }}</ref>
* Myopia between −0.00 and −0.50 diopters is usually classified as [[emmetropia]].
* Low myopia usually describes myopia between −0.50 and −3.00 diopters.<ref name="Cline" />
* Moderate myopia usually describes myopia between −3.00 and −6.00 [[diopters]].<ref name="Cline" /> Those with moderate amounts of myopia are more likely to have [[pigment dispersion syndrome]] or [[glaucoma|pigmentary glaucoma]].<ref>[http://www.eyemdlink.com/Condition.asp?ConditionID=2 "Glaucoma."] {{webarchive|url=https://web.archive.org/web/20060819160824/http://www.eyemdlink.com/Condition.asp?ConditionID=2 |date=19 August 2006 }} EyeMDLink.com. Retrieved 27 August 2006.</ref>
* High myopia usually describes myopia of −6.00 or more.<ref name="Cline" /><ref>{{cite journal |last1=Zejmo |first1=Maria |last2=Formińska-Kapuścik |first2=Maria |last3=Pieczara |first3=Ewa |last4=Filipek |first4=Erita |last5=Mrukwa-Kominek |first5=Ewa |last6=Samochowiec-Donocik |first6=Elzbieta |last7=Leszczyński |first7=Rafal |last8=Smuzyńska |first8=Magdalena |title=Etiopathogenesis and management of high-degree myopia. Part I |journal=Medical Science Monitor |date=September 2009 |volume=15 |issue=9 |pages=RA199-202 |pmid=19721411 |id={{INIST|21992936}} |url=https://www.medscimonit.com/abstract/index/idArt/878169 }}</ref> People with high myopia are more likely to have [[retinal detachment]]s<ref>{{EMedicine|article|798501|Retinal Detachment}}</ref> and [[glaucoma|primary open angle glaucoma]].<ref>[https://web.archive.org/web/20040204164358/http://www.agingeye.net/glaucoma/glaucomainformation.php "More Information on Glaucoma."] AgingEye Times. Retrieved 27 August 2006.</ref> They are also more likely to experience [[floater]]s, shadow-like shapes which appear in the [[visual field|field of vision]].<ref>{{cite journal | vauthors = Messmer DE | title = [Retinal detachment] | language = de | journal = Schweizerische Rundschau für Medizin Praxis = Revue Suisse de Médecine Praxis | volume = 81 | issue = 19 | pages = 622–5 | date = May 1992 | pmid = 1589678 }}</ref> In addition to this, high myopia is linked to macular degeneration, cataracts, and significant visual impairment.<ref>Banerjee S, Horton J. Lenses and Spectacles to Prevent Myopia Worsening in Children [Internet]. Ottawa (ON): Canadian Agency for Drugs and Technologies in Health; 2021 Apr. Available from:[https://www.ncbi.nlm.nih.gov/books/NBK571917/]</ref><ref>Walline JJ, Walker MK, Mutti DO, et al. Effect of High Add Power, Medium Add Power, or Single-Vision Contact Lenses on Myopia Progression in Children: The BLINK Randomized Clinical Trial. JAMA. 2020;324(6):571–580.</ref><ref>Ruiz-Pomeda A, Perez-Sanchez B, Valls I, Prieto-Garrido FL, Gutierrez-Ortega R, Villa-Collar C. MiSight Assessment Study Spain (MASS). A 2-year randomized clinical trial. Graefes Arch Clin Exp Ophthalmol. 2018;256(5):1011–1021.</ref><ref>Garcia-Del Valle AM, Blazquez V, Gros-Otero J, et al. Efficacy and safety of a soft contact lens to control myopia progression. Clin Exp Optom.2021;104(1):14–21</ref>
The highest myopia ever recorded was −108 diopters by a [[Slovakia|Slovak]], Jan Miskovic.<ref>{{cite web |last1=Fitoussi |first1=Stephane |title=The World Record of Myopia |date=23 May 2023 |url=https://fluorescene.odcommunity.com/11232-2/}}</ref>

===Age at onset===
Myopia is sometimes classified by the age at onset:<ref name="Grosvenor" />
* Congenital myopia, also known as infantile myopia, is present at birth and persists through infancy.<ref name="AOA" />
* Youth onset myopia occurs in early childhood or teenage, and the ocular power can keep varying until the age of 21, before which any form of corrective surgery is usually not recommended by ophthalmic specialists around the world.<ref name="AOA" />
* School myopia appears during childhood, particularly the school age years.<ref name="Morgan 1">{{cite journal | vauthors = Morgan I, Rose K | title = How genetic is school myopia? | journal = Progress in Retinal and Eye Research | volume = 24 | issue = 1 | pages = 1–38 | date = January 2005 | pmid = 15555525 | doi = 10.1016/j.preteyeres.2004.06.004 | s2cid = 18045281 }}</ref> This form of myopia is attributed to the use of the eyes for close work during the school years.<ref name="Cline" /> A 2004–2015 Singapore–Sydney study of children of Chinese descent found that time spent on outdoor activities was a factor.<ref>{{Cite web |url=http://www.smj.org.sg/article/school-based-programme-address-childhood-myopia-singapore |title=School based program |access-date=10 November 2022 |archive-date=10 November 2022 |archive-url=https://web.archive.org/web/20221110222346/http://www.smj.org.sg/article/school-based-programme-address-childhood-myopia-singapore |url-status=dead }}</ref>
* Adult onset myopia

:* Early adult onset myopia occurs between ages 20 and 40.<ref name="AOA" />
:*Late adult onset myopia occurs after age 40.<ref name="AOA" />