{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T06:07:12Z","timestamp":1788242832026,"version":"build-2803163510"},"reference-count":35,"publisher":"Public Library of Science (PLoS)","issue":"4","license":[{"start":{"date-parts":[[2024,4,16]],"date-time":"2024-04-16T00:00:00Z","timestamp":1713225600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["81200669"],"award-info":[{"award-number":["81200669"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Purpose<\/jats:title>\n<jats:p>This study aimed to investigate the underlying factors driving the onset of myopia, specifically the role of the ciliary muscle\u2019s contraction in the elongation of the axial length of the eye.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods<\/jats:title>\n<jats:p>The retrospective study was conducted utilizing data from three ophthalmic centers in Shanghai and Beijing. Both Chinese and Caucasian children were involved. The axial length of the subjects\u2019 eyes was measured in both relaxed and contracted state of the ciliary muscle. A comprehensive mechanical model was also developed to observe the influence of ciliary muscle contraction on the axial length.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>This study included a sample of 198 right eyes of 198 myopic children. Of these, 97 were male and 101 were female, 126 were of Chinese ethnicity and 72 were Caucasian. The age of onset for myopia ranged from 5.9 to 16.9 years old. The axial length of the eye decreased 0.028 \u00b1 0.007mm following dilation, indicating relaxation of the ciliary muscle (t <jats:sub>paired student<\/jats:sub> = 15.16, p = 6.72 x 10<jats:sup>\u221235<\/jats:sup>). In contrast, ciliary muscle contraction resulted in an increase in axial length. Considering proportionality, a significant 90.4% (179 eyes) exhibited a reduced axial length, while a minor 9.6% (19 eyes) demonstrated an increase post-mydriasis. Finite element modeling demonstrated that muscle contraction caused a tension force that transmits towards the posterior pole of the eye, causing it to extend posteriorly.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusion<\/jats:title>\n<jats:p>The contraction of the ciliary muscle leads to an extension of the axial length. This could potentially be the initiating factor for myopia.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0301844","type":"journal-article","created":{"date-parts":[[2024,4,16]],"date-time":"2024-04-16T18:24:31Z","timestamp":1713291871000},"page":"e0301844","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":12,"title":["Ciliary muscles contraction leads to axial length extension\u2014\u2014The possible initiating factor for myopia"],"prefix":"10.1371","volume":"19","author":[{"given":"Zhao-Yang","family":"Meng","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lin","family":"Yang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1744-5167","authenticated-orcid":true,"given":"Peng","family":"Zhou","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2024,4,16]]},"reference":[{"issue":"1","key":"pone.0301844.ref001","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1038\/s41572-020-00231-4","article-title":"Myopia.","volume":"6","author":"PN Baird","year":"2020","journal-title":"Nat Rev Dis Primers"},{"key":"pone.0301844.ref002","doi-asserted-by":"crossref","first-page":"134","DOI":"10.1016\/j.preteyeres.2017.09.004","article-title":"The epidemics of myopia: Aetiology and prevention.","volume":"62","author":"IG Morgan","year":"2018","journal-title":"Prog Retin Eye Res"},{"issue":"6","key":"pone.0301844.ref003","doi-asserted-by":"crossref","first-page":"386","DOI":"10.1097\/APO.0000000000000236","article-title":"Epidemiology of Myopia.","volume":"5","author":"PC Wu","year":"2016","journal-title":"Asia Pac J Ophthalmol (Phila)."},{"issue":"5","key":"pone.0301844.ref004","doi-asserted-by":"crossref","first-page":"1036","DOI":"10.1016\/j.ophtha.2016.01.006","article-title":"Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 2050","volume":"123","author":"BA Holden","year":"2016","journal-title":"Ophthalmology"},{"issue":"5","key":"pone.0301844.ref005","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1167\/iovs.62.5.6","article-title":"IMI Prevention of Myopia and Its Progression","volume":"62","author":"Johnson & Johnson","year":"2021","journal-title":"Invest Ophthalmol Vis Sci"},{"issue":"1","key":"pone.0301844.ref006","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1080\/09273972.2016.1276940","article-title":"Interventions to Reduce Myopia Progression in Children.","volume":"25","author":"SA Tay","year":"2017","journal-title":"Strabismus."},{"issue":"2","key":"pone.0301844.ref007","doi-asserted-by":"crossref","first-page":"488","DOI":"10.1016\/j.survophthal.2021.06.005","article-title":"The cause of myopia development and progression: Theory, evidence, and treatment","volume":"67","author":"A. 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