|
| |
 |
|
| REVIEW ARTICLE |
|
| Year : 2022 | Volume
: 4
| Issue : 1 | Page : 17 |
|
Myopia is progressing faster than its management options
Ali Nouraeinejad
Department of Clinical Ophthalmology, Institute of Ophthalmology, University College London, London, United Kingdom
| Date of Submission | 16-Nov-2021 |
| Date of Decision | 03-Jan-2022 |
| Date of Acceptance | 03-Feb-2022 |
| Date of Web Publication | 25-Mar-2022 |
Correspondence Address:
Dr. Ali Nouraeinejad
Department of Clinical Ophthalmology, Institute of Ophthalmology, University College London, London
United Kingdom
 Source of Support: None, Conflict of Interest: None
DOI: 10.4103/pajo.pajo_119_21
Myopia, as the most common source of distance vision impairment in the world, is a serious global public health and socioeconomic crisis. Although more than half of the world population will be myopic by 2050, none of the myopia control strategies has been demonstrated to completely stop the development or progression of myopia. This is due to the fact that myopia is progressing faster than its management options. It should also be emphasized that none of the current myopia control strategies is practically in use for some reason except for research purposes. It is of critical importance to realize that without any effectual controls or therapeutic interventions, myopia crisis enlarges further.
Keywords: Environmental factors, genetics, myopia control, myopia progression, myopia
How to cite this article:
Nouraeinejad A. Myopia is progressing faster than its management options. Pan Am J Ophthalmol 2022;4:17 |
| Introduction | |  |
Myopia is generally defined as “a refractive condition of the eye in which parallel rays of light entering the eye are brought to a focus in front of the retina when the ocular accommodation is relaxed.”[1],[2],[3]
Myopia is a serious global public health and socioeconomic crisis.[1],[2],[3],[4],[5] Recent analyses of 145 studies regarding the global prevalence of myopia and high myopia have shown that 28.3% and 4.0% of the world population have myopia and high myopia, respectively, and these figures are expected to boost to 49.8% and 9.8% of the world population for myopia and high myopia, correspondingly by 2050.[1],[2],[3],[4],[5] This will include 4758 million people for myopia and 938 million for high myopia by 2050.[1],[2],[3],[4],[5] These trends will be enough to worry about to realize how big the problem is.[1],[2],[3],[4],[5]
To clarify a few important basic descriptions, in the beginning, it is worth mentioning that the definitions of “myopia,” “high myopia,” and “pathologic myopia” have not been standardized.[1] For example, the term “pathologic myopia” is frequently confused with “high myopia.”[1] However, “high myopia” and “pathologic myopia” are distinctly different.[1] “High myopia” is defined as an eye with a high degree of myopic refractive error so that the spherical equivalent refractive error of an eye is equal or larger than − 6.00 D when ocular accommodation is relaxed, and “pathologic myopia” is defined as a myopic eye with the presence of pathologic lesions and degenerative changes in the posterior fundus.[1]
It is also important to learn that pathologic myopia is a major source of blindness or vision impairment in both Asian and Western countries[1],[2],[6],[7],[8],[9],[10] so that over 200 million people will be affected by pathologic myopia by 2050.[1],[5] The main basis of blindness in patients with pathologic myopia comprises “myopic maculopathy with or without posterior staphyloma,” “myopic macular retinoschisis,” and “glaucoma or glaucoma-like optic neuropathy.”[1] The term “pathologic myopia” represents the condition of pathologic consequences of a myopic axial elongation.[1] In a current consensus, pathologic myopia was identified as “myopic chorioretinal atrophy equal to or more serious than diffuse atrophy” and/or “the presence of posterior staphylomas.”[11],[12] It is also unfortunate to be informed that currently practised treatment methods against pathologic myopia have not been totally effective in stopping the pathological progression.[1],[13] However as it was defined earlier, there are many types of myopia and not all myopic individuals go blind.[1]
| Myopia in Children | | |
There are plenty of documents showing myopia mostly develops in school-age children so that the prevalence of myopia begins to rise after the age of 6 years when the schooling starts.[14],[15],[16],[17],[18],[19] The development of myopia in school-age children has been demonstrated to be related with various factors including Asian ethnicity,[16],[20] parental history of myopia,[21],[22] reduced time spent outdoors,[21] and increased level of near-work activity.[23],[24] The majority of increased myopia onset was shown to be related to increased educational intensity.[14] This highlights an important role for policymakers to balance educational achievement and myopic interventions to prevent myopia progression, especially in East Asia.[1] This can be tough to manage in East Asian countries and surely requires a collaborative effort among clinics, schools, parents, and the entire society.[1]
| Etiology of Myopia | | |
Any disruption to the highly coordinated ocular changes during the process of emmetropization, an active regulatory process that harmonizes the expansion of the eye with the optical power of the cornea and the crystalline lens, leads to the development of refractive errors during the early period of visual development.[1]
The quality of the retinal image of visual environment also modulates the refractive development of the eye throughout the visual experience both in the early period of visual development or even later in life.[1] Ocular response to form-deprivation and lens-induced defocus is evident across a wide range of animal species, including humans.[1]
Myopia is a highly heritable trait, along with environmental influences, such as increased near work and insufficient outdoor activity acting significant parts in its development and progression.[1] Based on the visually guided ocular growth mechanism, relative peripheral hyperopia in corrected myopia provokes axial elongation in order to reduce relative peripheral hyperopia in these cases.[1]
The prevalence of myopia in children, teenagers, and young adults is significantly higher in urban East Asian countries compared with other countries.[5],[25],[26],[27] However, the prevalence rates of myopia in adults in urban East Asian countries are just slightly higher than in Western countries.[1],[5] This brings the possibility of increased educational intensity as a factor for myopia progression in East Asian countries during recent years.[1] Generational differences in the prevalence of myopia and high myopia have been documented with the highest rates in young adults and the lowest rates in older adults.[1] This may be due to generational differences, or changes in the lifestyle components, such as the type of educational system, intensity of near work, and outdoor time exposure in rapidly developing urban settings in many Asian countries.[1] These documents are supportive as the evidence that myopia is not caused by purely genetic differences.[1],[27]
These various potential causes of myopia development are the main factors for different treatment options in myopia.[1]
Genetics of myopia
The propensity for myopia to occur in families has long been documented, indicating the role of genetic factors in discovering the total risk.[1] Myopia is extremely heritable[28],[29],[30],[31],[32],[33],[34],[35],[36],[37],[38],[39],[40],[41],[42],[43] so that genes explain up to 80% of the variance in refractive error in twin studies.[1] However, clinical implications obtained from genetic analyses of myopia are limited at present. This is in view of the high polygenicity of myopia and low explained phenotypic variance by genetic factors (7.8%).[1] Gene–environment interaction analyses are ongoing to evaluate whether genes act differently across different environments.[1]
Key environmental factors on myopia
Outdoor activity
Consistent results of both cross-sectional and longitudinal studies regarding evidence of insufficient time spent outdoors as a risk factor for myopia progression have been presented.[1],[21],[44],[45],[46],[47],[48],[49],[50],[51],[52],[53],[54],[55],[56],[57],[58],[59] In this regard, the randomized clinical trial in Guangzhou found that an additional 40 min of outdoor activity can diminish the incidence of myopia by 23%.[45] Other trials also found that an extra 80 min may further reduce the incidence of myopia by 50%.[51],[53] These studies have proved a dose-dependent effect of time spent outdoors in the prevalence of myopia.[1] Therefore, the duration of outdoor activities is also influential.[1]
Different reasons for the protective efficacy of time spent outdoors in myopes have been suggested. These probable reasons include higher light intensities,[60] differences in chromatic composition,[61] the reduction in dioptric accommodative focus and psychometric influences encountered outdoors,[62] and the role of chromaticity (red and blue) and ultraviolet light.[63] Outdoor activity and/or bright light were also shown to inhibit myopia, potentially through increased dopamine and vitamin D levels.[1]
Near work and education
Near-work activity as a risk factor for myopia has been proved.[24],[64],[65],[66],[67],[68],[69] Many studies have also confirmed a strong association between myopia and education.[39],[43],[70],[71],[72],[73] In this regard, exposure to longer duration of education was found to be a causal risk factor for myopia.[43]
Optical[74],[75] or biomechanical[76],[77] ocular changes associated with near-work activities have been suggested as the reasons for advancing myopic eye growth in those myopic individuals with higher levels of education, which can demand higher near-work requirements.[1],[24],[65]
| Correction and Control of Myopia | | |
Myopia can be corrected by several ways including spectacle lenses, contact lenses, and laser surgeries and these methods have been established for ages.[1] The correction of myopia to induce clear vision has been successful.[1] There are currently many eye surgeries to correct myopia. These include laser in situ keratomileusis (LASIK), laser subepithelial keratomileusis, wavefront-based excimer laser refractive surgery, photorefractive keratectomy (PRK), epithelial LASIK, intrastromal corneal ring segments, small incision lenticule extraction, phakic intraocular lenses, and refractive lens exchange with implantation of multifocal or monofocal intraocular lenses.[1]
Advanced ocular imaging is also vital to discover complications of pathologic myopia in order to start both medical and surgical interventions as part of their management.[1]
On the other hand, to control the myopia progression, there are many forms of preventive interventions including bifocal spectacle lenses,[78],[79] progressive addition lenses,[80],[81],[82],[83],[84],[85],[86],[87] special spectacle lens with defocus incorporated multiple segments (DIMS),[88],[89],[90],[91] spectacle lens designed to reduce relative peripheral hyperopia,[92],[93] soft contact lenses, rigid gas permeable contact lenses,[94],[95] soft bifocal and multifocal contact lenses,[96],[97],[98],[99],[100],[101] orthokeratology (Ortho-K),[102],[103],[104],[105],[106],[107],[108],[109] pharmaceuticals,[110],[111],[112],[113],[114] and environmental or behavioral modification.[1],[44],[45],[46],[47],[48],[51],[53],[57] For example, children aged 8–13 years who wore special spectacle lenses with DIMS were shown to have about 60% less myopia progression and axial elongation compared with children wearing single vision spectacle lenses over 2 years.[88] Another example is the application of soft bifocal and multifocal contact lenses, which has shown to slow the progression of myopia in children by an amount comparable to that of Ortho-K lenses. In this regard, the effect of these bifocal soft contact lenses has shown to slow myopia progression by 25%–50% and axial length by 27%–32% in children aged 8–16 of an assortment of ethnicities over a period of 24 months.[98],[99] Combination therapy of different methods (e.g., the combination of Ortho-K and low-concentration atropine [0.01%] eye drops) has also been tried so that the combination of Ortho-K and low-concentration atropine (0.01%) eye drops was shown to be more effective in slowing axial elongation over 12 months than Ortho-K treatment alone in myopic children.[115]
Pharmaceuticals have also been tried to slow myopia progression. One of these pharmaceuticals has been the usage of different doses of atropine (1.0%, 0.5%, 0.1%, 0.05% or less).[110],[111],[112],[113],[114],[116],[117],[118],[119],[120] The efficacy of atropine in myopia control was found to be dose related so that 0.05% atropine has been reported to be the optimal dose.[118],[119] While high doses of atropine (i.e., 0.5% or 1.0%) were shown to slow myopia progression by more than 70% in Asian children aged 6–13 years over 1–2 years,[110],[111],[112],[113],[114] lower doses (0.1% or less) were also reported to slow myopia progression by 30%–60% with less side effects (pupil dilation, glare, or blur).[114] However, a myopic rebound has also been reported if atropine was abruptly stopped, especially at higher doses and in younger children.[113],[114]
In addition to all of those above-mentioned documents regarding myopia control, there are many others explaining the benefit of different forms of interventions for myopia control.[121],[122],[123],[124],[125] However, none of these myopia control strategies has been unfortunately shown to fully stop the development or progression of myopia.[1] There have even been some adverse reactions for some of these control methods. For instance, the risk of infective keratitis remains high for contact lens users or those individuals who try Ortho-K.[126]
| Myopia is Progressing Faster than its Management Options | | |
Unfortunately, myopia is progressing faster than its management options.[1] This is simply due to the fact that none of the current myopia control strategies has been unfortunately shown to fully stop the development or progression of myopia while myopia keeps on striking millions of people worldwide.[1] As the global health burden of myopia continues to boost, the myopia control strategies are still on the rocks.[1] Therefore, this calls for newer effectual controls or therapeutic interventions to combat the crisis.[1] In spite of that, it should also be emphasized that none of the current myopia control strategies is practically in use for some reason except for research purposes.[1] The lack of usage of these preventive approaches and methods is going to worsen the myopia crisis as they have at least shown to be effective to some extent in many studies.[1]
It is of critical importance to realize that without any effectual controls or therapeutic interventions the percentage of myopes and high myopes in the world will reach up to 50% and 10%, respectively by 2050.[5] For this reason, effective controls or beneficial interventions, such as more time spent outdoors and less near-work activities should be part of the management options leading to delayed onset of myopia and have the potential to make a noteworthy difference on the future myopia epidemic.[1]
Moreover, emerging infectious diseases (EIDs), such as coronavirus disease-2019 and influenza A virus subtype H1N1 have been shown to indirectly lead to the progression of myopia.[3] In view of the fact that these EIDs are repetitively developing worldwide, they are anticipated to affect the behavior of people pressurizing them to stay more often at home and this is going to come about quite often in the future.[3] Therefore, this will add more chances of getting myopia in the future due to the association of myopia progression and near work imposed by home quarantine.[1]
| Conclusion | | |
Myopia is a serious global public health and socioeconomic crisis. Even supposing that no clear-cut management options have been established so far to fully stop myopia progression, success has been accomplished in slowing the rate of progression via optical and pharmaceutical intervention strategies as well as time spent outdoors and behavioral influences. That is why there should not be any hesitation to put these preventive procedures into practice in the course of policies and approaches. Otherwise, the myopia crisis will be worse than expected in the future. This is simply due to the fact that myopia is progressing faster than its management options.
Acknowledgments
The author would like to express his honest gratitude and high respect for the lifetime support of his father, Mohammad Nouraeinejad.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
| References | | |
| 1. | Nouraeinejad A. Differential Diagnosis in Optometry and Ophthalmology. 2 nd ed. Iran: Noruzi Publication; 2017.  |
| 2. | Nouraeinejad A. A warning message from 2020 to 2050: More than half of the world population will be myopic by 2050. London: Moorfields Eye Hospital; 2020. |
| 3. | Nouraeinejad A. The influence of coronavirus disease 2019 on myopia progression. Eur Eye Res 2021;1:113-4. |
| 4. | Nouraeinejad A. The myopia impact. Acta Sci Ophthalmol 2021;4:35-6. |
| 5. | Holden BA, Fricke TR, Wilson DA, Jong M, Naidoo KS, Sankaridurg P, et al. Global prevalence of myopia and high myopia and temporal trends from 2000 through 2050. Ophthalmology 2016;123:1036-42. |
| 6. | Hsu WM, Cheng CY, Liu JH, Tsai SY, Chou P. Prevalence and causes of visual impairment in an elderly Chinese population in Taiwan: The Shihpai Eye Study. Ophthalmology 2004;111:62-9. |
| 7. | Iwase A, Araie M, Tomidokoro A, Yamamoto T, Shimizu H, Kitazawa Y, et al. Prevalence and causes of low vision and blindness in a Japanese adult population: The Tajimi Study. Ophthalmology 2006;113:1354-62. |
| 8. | Xu L, Wang Y, Li Y, Wang Y, Cui T, Li J, et al. Causes of blindness and visual impairment in urban and rural areas in Beijing: The Beijing Eye Study. Ophthalmology 2006;113:1134.e1-11. |
| 9. | Yamada M, Hiratsuka Y, Roberts CB, Pezzullo ML, Yates K, Takano S, et al. Prevalence of visual impairment in the adult Japanese population by cause and severity and future projections. Ophthalmic Epidemiol 2010;17:50-7. |
| 10. | You QS, Xu L, Yang H, Wang YX, Jonas JB. Five-year incidence of visual impairment and blindness in adult Chinese the Beijing Eye Study. Ophthalmology 2011;118:1069-75. |
| 11. | Ohno-Matsui K, Kawasaki R, Jonas JB, Cheung CM, Saw SM, Verhoeven VJ, et al. International photographic classification and grading system for myopic maculopathy. Am J Ophthalmol 2015;159:877-83.e7. |
| 12. | Ohno-Matsui K, Lai TY, Lai CC, Cheung CM. Updates of pathologic myopia. Prog Retin Eye Res 2016;52:156-87. |
| 13. | Wong TY, Ferreira A, Hughes R, Carter G, Mitchell P. Epidemiology and disease burden of pathologic myopia and myopic choroidal neovascularization: An evidence-based systematic review. Am J Ophthalmol 2014;157:9-25.e12. |
| 14. | Matsumura H, Hirai H. Prevalence of myopia and refractive changes in students from 3 to 17 years of age. Surv Ophthalmol 1999;44 Suppl 1:S109-15. |
| 15. | Zhao J, Mao J, Luo R, Li F, Munoz SR, Ellwein LB. The progression of refractive error in school-age children: Shunyi district, China. Am J Ophthalmol 2002;134:735-43. |
| 16. | Saw SM, Tong L, Chua WH, Chia KS, Koh D, Tan DT, et al. Incidence and progression of myopia in Singaporean school children. Invest Ophthalmol Vis Sci 2005;46:51-7. |
| 17. | Xiang F, He M, Zeng Y, Mai J, Rose KA, Morgan IG. Increases in the prevalence of reduced visual acuity and myopia in Chinese children in Guangzhou over the past 20 years. Eye (Lond) 2013;27:1353-8. |
| 18. | Tsai DC, Fang SY, Huang N, Hsu CC, Chen SY, Chiu AW, et al. Myopia development among young schoolchildren: The myopia investigation study in Taipei. Invest Ophthalmol Vis Sci 2016;57:6852-60. |
| 19. | Wang SK, Guo Y, Liao C, Chen Y, Su G, Zhang G, et al. Incidence of and factors associated with myopia and high myopia in Chinese children, based on refraction without cycloplegia. JAMA Ophthalmol 2018;136:1017-24. |
| 20. | French AN, Morgan IG, Burlutsky G, Mitchell P, Rose KA. Prevalence and 5- to 6-year incidence and progression of myopia and hyperopia in Australian schoolchildren. Ophthalmology 2013;120:1482-91. |
| 21. | Jones LA, Sinnott LT, Mutti DO, Mitchell GL, Moeschberger ML, Zadnik K. Parental history of myopia, sports and outdoor activities, and future myopia. Invest Ophthalmol Vis Sci 2007;48:3524-32. |
| 22. | Jones-Jordan LA, Sinnott LT, Manny RE, Cotter SA, Kleinstein RN, Mutti DO, et al. Early childhood refractive error and parental history of myopia as predictors of myopia. Invest Ophthalmol Vis Sci 2010;51:115-21. |
| 23. | 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 a UK cohort of children. Br J Ophthalmol 2008;92:1117-21. |
| 24. | Huang HM, Chang DS, Wu PC. The association between near work activities and myopia in children – A systematic review and meta-analysis. PLoS One 2015;10:e0140419. |
| 25. | Lin LL, Shih YF, Hsiao CK, Chen CJ. Prevalence of myopia in Taiwanese schoolchildren: 1983 to 2000. Ann Acad Med Singap 2004;33:27-33. |
| 26. | Jung SK, Lee JH, Kakizaki H, Jee D. Prevalence of myopia and its association with body stature and educational level in 19-year-old male conscripts in Seoul, South Korea. Invest Ophthalmol Vis Sci 2012;53:5579-83. |
| 27. | Ding BY, Shih YF, Lin LL, Hsiao CK, Wang IJ. Myopia among schoolchildren in East Asia and Singapore. Surv Ophthalmol 2017;62:677-97. |
| 28. | Smith GD, Ebrahim S. Mendelian randomization: Prospects, potentials, and limitations. Int J Epidemiol 2004;33:30-42. |
| 29. | Mutti DO, Cooper ME, O'Brien S, Jones LA, Marazita ML, Murray JC, et al. Candidate gene and locus analysis of myopia. Mol Vis 2007;13:1012-9. |
| 30. | Ebrahim S, Davey Smith G. Mendelian randomization: Can genetic epidemiology help redress the failures of observational epidemiology? Hum Genet 2008;123:15-33. |
| 31. | Hall NF, Gale CR, Ye S, Martyn CN. Myopia and polymorphisms in genes for matrix metalloproteinases. Invest Ophthalmol Vis Sci 2009;50:2632-6. |
| 32. | Metlapally R, Li YJ, Tran-Viet KN, Abbott D, Czaja GR, Malecaze F, et al. COL1A1 and COL2A1 genes and myopia susceptibility: Evidence of association and suggestive linkage to the COL2A1 locus. Invest Ophthalmol Vis Sci 2009;50:4080-6. |
| 33. | Wojciechowski R, Bailey-Wilson JE, Stambolian D. Association of matrix metalloproteinase gene polymorphisms with refractive error in Amish and Ashkenazi families. Invest Ophthalmol Vis Sci 2010;51:4989-95. |
| 34. | Verhoeven VJ, Buitendijk GH, Consortium for Refractive Error and Myopia (CREAM); Rivadeneira F, Uitterlinden AG, Vingerling JR, Hofman A, et al. Education influences the role of genetics in myopia. Eur J Epidemiol 2013;28:973-80. |
| 35. | Wojciechowski R, Yee SS, Simpson CL, Bailey-Wilson JE, Stambolian D. Matrix metalloproteinases and educational attainment in refractive error: Evidence of gene-environment interactions in the Age-Related Eye Disease Study. Ophthalmology 2013;120:298-305. |
| 36. | Tang SM, Rong SS, Young AL, Tam PO, Pang CP, Chen LJ. PAX6 gene associated with high myopia: A meta-analysis. Optom Vis Sci 2014;91:419-29. |
| 37. | Fan Q, Wojciechowski R, Kamran Ikram M, Cheng CY, Chen P, Zhou X, et al. Education influences the association between genetic variants and refractive error: A meta-analysis of five Singapore studies. Hum Mol Genet 2014;23:546-54. |
| 38. | Fan Q, Guo X, Tideman JW, Williams KM, Yazar S, Hosseini SM, et al. Childhood gene-environment interactions and age-dependent effects of genetic variants associated with refractive error and myopia: The CREAM Consortium. Sci Rep 2016;6:25853. |
| 39. | Cuellar-Partida G, Lu Y, Kho PF, Hewitt AW, Wichmann HE, Yazar S, et al. Assessing the genetic predisposition of education on myopia: A Mendelian randomization study. Genet Epidemiol 2016;40:66-72. |
| 40. | Cuellar-Partida G, Williams KM, Yazar S, Guggenheim JA, Hewitt AW, Williams C, et al. Genetically low vitamin D concentrations and myopic refractive error: A Mendelian randomization study. Int J Epidemiol 2017;46:1882-90. |
| 41. | Ghorbani Mojarrad N, Williams C, Guggenheim JA. A genetic risk score and number of myopic parents independently predict myopia. Ophthalmic Physiol Opt 2018;38:492-502. |
| 42. | Tedja MS, Wojciechowski R, Hysi PG, Eriksson N, Furlotte NA, Verhoeven VJ, et al. Genome-wide association meta-analysis highlights light-induced signaling as a driver for refractive error. Nat Genet 2018;50:834-48. |
| 43. | Mountjoy E, Davies NM, Plotnikov D, Smith GD, Rodriguez S, Williams CE, et al. Education and myopia: Assessing the direction of causality by Mendelian randomisation. BMJ 2018;361:k2022. |
| 44. | Pärssinen O, Lyyra AL. Myopia and myopic progression among schoolchildren: A three-year follow-up study. Invest Ophthalmol Vis Sci 1993;34:2794-802. |
| 45. | Mutti DO, Mitchell GL, Moeschberger ML, Jones LA, Zadnik K. Parental myopia, near work, school achievement, and children's refractive error. Invest Ophthalmol Vis Sci 2002;43:3633-40. |
| 46. | Rose KA, Morgan IG, Ip J, Kifley A, Huynh S, Smith W, et al. Outdoor activity reduces the prevalence of myopia in children. Ophthalmology 2008;115:1279-85. |
| 47. | Dirani M, Tong L, Gazzard G, Zhang X, Chia A, Young TL, et al. Outdoor activity and myopia in Singapore teenage children. Br J Ophthalmol 2009;93:997-1000. |
| 48. | Sherwin JC, Reacher MH, Keogh RH, Khawaja AP, Mackey DA, Foster PJ. The association between time spent outdoors and myopia in children and adolescents: A systematic review and meta-analysis. Ophthalmology 2012;119:2141-51. |
| 49. | Guggenheim JA, Northstone K, McMahon G, Ness AR, Deere K, Mattocks C, et al. Time outdoors and physical activity as predictors of incident myopia in childhood: A prospective cohort study. Invest Ophthalmol Vis Sci 2012;53:2856-65. |
| 50. | Jones-Jordan LA, Sinnott LT, Cotter SA, Kleinstein RN, Manny RE, Mutti DO, et al. Time outdoors, visual activity, and myopia progression in juvenile-onset myopes. Invest Ophthalmol Vis Sci 2012;53:7169-75. |
| 51. | Wu PC, Tsai CL, Wu HL, Yang YH, Kuo HK. Outdoor activity during class recess reduces myopia onset and progression in school children. Ophthalmology 2013;120:1080-5. |
| 52. | Pärssinen O, Kauppinen M, Viljanen A. The progression of myopia from its onset at age 8-12 to adulthood and the influence of heredity and external factors on myopic progression. A 23-year follow-up study. Acta Ophthalmol 2014;92:730-9. |
| 53. | He M, Xiang F, Zeng Y, Mai J, Chen Q, Zhang J, et al. Effect of time spent outdoors at school on the development of myopia among children in China: A randomized clinical trial. JAMA 2015;314:1142-8. |
| 54. | Read SA, Collins MJ, Vincent SJ. Light exposure and eye growth in childhood. Invest Ophthalmol Vis Sci 2015;56:6779-87. |
| 55. | Guo Y, Liu LJ, Tang P, Lv YY, Feng Y, Xu L, et al. Outdoor activity and myopia progression in 4-year follow-up of Chinese primary school children: The Beijing Children Eye Study. PLoS One 2017;12:e0175921. |
| 56. | Xiong S, Sankaridurg P, Naduvilath T, Zang J, Zou H, Zhu J, et al. Time spent in outdoor activities in relation to myopia prevention and control: A meta-analysis and systematic review. Acta Ophthalmol 2017;95:551-66. |
| 57. | Wu PC, Chen CT, Lin KK, Sun CC, Kuo CN, Huang HM, et al. Myopia prevention and outdoor light intensity in a school-based cluster randomized trial. Ophthalmology 2018;125:1239-50. |
| 58. | Cao K, Wan Y, Yusufu M, Wang N. Significance of outdoor time for myopia prevention: A systematic review and meta-analysis based on randomized controlled trials. Ophthalmic Res 2020;63:97-105. |
| 59. | Lingham G, Yazar S, Lucas RM, Milne E, Hewitt AW, Hammond CJ, et al. Time spent outdoors in childhood is associated with reduced risk of myopia as an adult. Sci Rep 2021;11:6337. |
| 60. | Ashby R, Ohlendorf A, Schaeffel F. The effect of ambient illuminance on the development of deprivation myopia in chicks. Invest Ophthalmol Vis Sci 2009;50:5348-54. |
| 61. | Seidemann A, Schaeffel F. Effects of longitudinal chromatic aberration on accommodation and emmetropization. Vision Res 2002;42:2409-17. |
| 62. | Flitcroft DI. The complex interactions of retinal, optical and environmental factors in myopia aetiology. Prog Retin Eye Res 2012;31:622-60. |
| 63. | Hung LF, Arumugam B, She Z, Ostrin L, Smith EL 3 rd. Narrow-band, long-wavelength lighting promotes hyperopia and retards vision-induced myopia in infant rhesus monkeys. Exp Eye Res 2018;176:147-60. |
| 64. | Kinge B, Midelfart A, Jacobsen G, Rystad J. The influence of near-work on development of myopia among university students. A three-year longitudinal study among engineering students in Norway. Acta Ophthalmol Scand 2000;78:26-9. |
| 65. | Hepsen IF, Evereklioglu C, Bayramlar H. The effect of reading and near-work on the development of myopia in emmetropic boys: A prospective, controlled, three-year follow-up study. Vision Res 2001;41:2511-20. |
| 66. | Saw SM, Zhang MZ, Hong RZ, Fu ZF, Pang MH, Tan DT. Near-work activity, night-lights, and myopia in the Singapore-China study. Arch Ophthalmol 2002;120:620-7. |
| 67. | Ip JM, Saw SM, Rose KA, Morgan IG, Kifley A, Wang JJ, et al. Role of near work in myopia: Findings in a sample of Australian school children. Invest Ophthalmol Vis Sci 2008;49:2903-10. |
| 68. | Gong Y, Zhang X, Tian D, Wang D, Xiao G. Parental myopia, near work, hours of sleep and myopia in Chinese children. Health 2014;6:64-70. |
| 69. | Williams R, Bakshi S, Ostrin EJ, Ostrin LA. Continuous objective assessment of near work. Sci Rep 2019;9:6901. |
| 70. | Williams KM, Bertelsen G, Cumberland P, Wolfram C, Verhoeven VJ, Anastasopoulos E, et al. Increasing prevalence of myopia in Europe and the impact of education. Ophthalmology 2015;122:1489-97. |
| 71. | Morgan IG, French AN, Ashby RS, Guo X, Ding X, He M, et al. The epidemics of myopia: Aetiology and prevention. Prog Retin Eye Res 2018;62:134-49. |
| 72. | Nickels S, Hopf S, Pfeiffer N, Schuster AK. Myopia is associated with education: Results from NHANES 1999-2008. PLoS One 2019;14:e0211196. |
| 73. | Han SB, Jang J, Yang HK, Hwang JM, Park SK. Prevalence and risk factors of myopia in adult Korean population: Korea National Health and Nutrition Examination Survey 2013-2014 (KNHANES VI). PLoS One 2019;14:e0211204. |
| 74. | Gwiazda J, Thorn F, Bauer J, Held R. Myopic children show insufficient accommodative response to blur. Invest Ophthalmol Vis Sci 1993;34:690-4. |
| 75. | Buehren T, Collins MJ, Carney LG. Near work induced wavefront aberrations in myopia. Vision Res 2005;45:1297-312. |
| 76. | Read SA, Collins MJ, Woodman EC, Cheong SH. Axial length changes during accommodation in myopes and emmetropes. Optom Vis Sci 2010;87:656-62. |
| 77. | Woodman-Pieterse EC, Read SA, Collins MJ, Alonso-Caneiro D. Regional changes in choroidal thickness associated with accommodation. Invest Ophthalmol Vis Sci 2015;56:6414-22. |
| 78. | Cheng D, Woo GC, Schmid KL. Bifocal lens control of myopic progression in children. Clin Exp Optom 2011;94:24-32. |
| 79. | Cheng D, Woo GC, Drobe B, Schmid KL. Effect of bifocal and prismatic bifocal spectacles on myopia progression in children: Three-year results of a randomized clinical trial. JAMA Ophthalmol 2014;132:258-64. |
| 80. | Edwards MH, Li RW, Lam CS, Lew JK, Yu BS. The Hong Kong progressive lens myopia control study: Study design and main findings. Invest Ophthalmol Vis Sci 2002;43:2852-8. |
| 81. | Gwiazda J, Hyman L, Hussein M, Everett D, Norton TT, Kurtz D, et al. A randomized clinical trial of progressive addition lenses versus single vision lenses on the progression of myopia in children. Invest Ophthalmol Vis Sci 2003;44:1492-500. |
| 82. | Hasebe S, Ohtsuki H, Nonaka T, Nakatsuka C, Miyata M, Hamasaki I, et al. Effect of progressive addition lenses on myopia progression in Japanese children: A prospective, randomized, double-masked, crossover trial. Invest Ophthalmol Vis Sci 2008;49:2781-9. |
| 83. | Yang Z, Lan W, Ge J, Liu W, Chen X, Chen L, et al. The effectiveness of progressive addition lenses on the progression of myopia in Chinese children. Ophthalmic Physiol Opt 2009;29:41-8. |
| 84. | Correction of Myopia Evaluation Trial 2 Study Group for the Pediatric Eye Disease Investigator Group. Progressive-addition lenses versus single-vision lenses for slowing progression of myopia in children with high accommodative lag and near esophoria. Invest Ophthalmol Vis Sci 2011;52:2749-57. |
| 85. | Walline JJ, Lindsley K, Vedula SS, Cotter SA, Mutti DO, Twelker JD. Interventions to slow progression of myopia in children. Cochrane Database Syst Rev 2011;12:CD004916. |
| 86. | Berntsen DA, Sinnott LT, Mutti DO, Zadnik K. A randomized trial using progressive addition lenses to evaluate theories of myopia progression in children with a high lag of accommodation. Invest Ophthalmol Vis Sci 2012;53:640-9. |
| 87. | Hasebe S, Jun J, Varnas SR. Myopia control with positively aspherized progressive addition lenses: A 2-year, multicenter, randomized, controlled trial. Invest Ophthalmol Vis Sci 2014;55:7177-88. |
| 88. | Zhang HY, Lam CS, Tang WC, Leung M, To CH. Defocus incorporated multiple segments spectacle lenses changed the relative peripheral refraction: A 2-year randomized clinical trial. Invest Ophthalmol Vis Sci 2020;61:53. |
| 89. | Li Y, Fu Y, Wang K, Liu Z, Shi X, Zhao M. Evaluating the myopia progression control efficacy of defocus incorporated multiple segments (DIMS) lenses and Apollo progressive addition spectacle lenses (PALs) in 6- to 12-year-old children: Study protocol for a prospective, multicenter, randomized controlled trial. Trials 2020;21:279. |
| 90. | Lu Y, Lin Z, Wen L, Gao W, Pan L, Li X, et al. The adaptation and acceptance of defocus incorporated multiple segment lens for Chinese children. Am J Ophthalmol 2020;211:207-16. |
| 91. | Lam CS, Tang WC, Tse DY, Kin Lee RP, Man Chun RK, Hasegawa K, et al. Defocus Incorporated Multiple Segments (DIMS) spectacle lenses slow myopia progression: A 2-year randomised clinical trial. Br J Ophthalmol 2020;104:363-8. |
| 92. | Sankaridurg P, Donovan L, Varnas S, Ho A, Chen X, Martinez A, et al. Spectacle lenses designed to reduce progression of myopia: 12-month results. Optom Vis Sci 2010;87:631-41. |
| 93. | Kanda H, Oshika T, Hiraoka T, Hasebe S, Ohno-Matsui K, Ishiko S, et al. Effect of spectacle lenses designed to reduce relative peripheral hyperopia on myopia progression in Japanese children: A 2-year multicenter randomized controlled trial. Jpn J Ophthalmol 2018;62:537-43. |
| 94. | Katz J, Schein OD, Levy B, Cruiscullo T, Saw SM, Rajan U, et al. A randomized trial of rigid gas permeable contact lenses to reduce progression of children's myopia. Am J Ophthalmol 2003;136:82-90. |
| 95. | Walline JJ, Jones LA, Mutti DO, Zadnik K. A randomized trial of the effects of rigid contact lenses on myopia progression. Arch Ophthalmol 2004;122:1760-6. |
| 96. | Walline JJ, Gaume A, Jones LA, Rah MJ, Manny RE, Berntsen DA, et al. Benefits of contact lens wear for children and teens. Eye Contact Lens 2007;33:317-21. |
| 97. | Rah MJ, Walline JJ, Jones-Jordan LA, Sinnott LT, Jackson JM, Manny RE, et al. Vision specific quality of life of pediatric contact lens wearers. Optom Vis Sci 2010;87:560-6. |
| 98. | Benavente-Pérez A, Nour A, Troilo D. Axial eye growth and refractive error development can be modified by exposing the peripheral retina to relative myopic or hyperopic defocus. Invest Ophthalmol Vis Sci 2014;55:6765-73. |
| 99. | Li SM, Kang MT, Wu SS, Meng B, Sun YY, Wei SF, et al. Studies using concentric ring bifocal and peripheral add multifocal contact lenses to slow myopia progression in school-aged children: A meta-analysis. Ophthalmic Physiol Opt 2017;37:51-9. |
| 100. | Zhu Q, Liu Y, Tighe S, Zhu Y, Su X, Lu F, et al. Retardation of myopia progression by multifocal soft contact lenses. Int J Med Sci 2019;16:198-202. |
| 101. | Achong-Coan R. Myopia control with multifocal contact lenses. Mod Optom 2020;26-8. |
| 102. | Cho P, Cheung SW, Edwards M. The longitudinal orthokeratology research in children (LORIC) in Hong Kong: A pilot study on refractive changes and myopic control. Curr Eye Res 2005;30:71-80. |
| 103. | Kakita T, Hiraoka T, Oshika T. Influence of overnight orthokeratology on axial elongation in childhood myopia. Invest Ophthalmol Vis Sci 2011;52:2170-4. |
| 104. | Cho P, Cheung SW. Retardation of myopia in orthokeratology (ROMIO) study: A 2-year randomized clinical trial. Invest Ophthalmol Vis Sci 2012;53:7077-85. |
| 105. | Hiraoka T, Kakita T, Okamoto F, Takahashi H, Oshika T. Long-term effect of overnight orthokeratology on axial length elongation in childhood myopia: A 5-year follow-up study. Invest Ophthalmol Vis Sci 2012;53:3913-9. |
| 106. | Charm J, Cho P. High myopia-partial reduction ortho-k: A 2-year randomized study. Optom Vis Sci 2013;90:530-9. |
| 107. | Wen D, Huang J, Chen H, Bao F, Savini G, Calossi A, et al. Efficacy and acceptability of orthokeratology for slowing myopic progression in children: A systematic review and meta-analysis. J Ophthalmol 2015;2015:360806. |
| 108. | Sun Y, Xu F, Zhang T, Liu M, Wang D, Chen Y, et al. Orthokeratology to control myopia progression: A meta-analysis. PLoS One 2015;10:e0124535. |
| 109. | Lee YC, Wang JH, Chiu CJ. Effect of orthokeratology on myopia progression: Twelve-year results of a retrospective cohort study. BMC Ophthalmol 2017;17:243. |
| 110. | Yen MY, Liu JH, Kao SC, Shiao CH. Comparison of the effect of atropine and cyclopentolate on myopia. Ann Ophthalmol 1989;21:180-2, 187. |
| 111. | Shih YF, Chen CH, Chou AC, Ho TC, Lin LL, Hung PT. Effects of different concentrations of atropine on controlling myopia in myopic children. J Ocul Pharmacol Ther 1999;15:85-90. |
| 112. | Chua WH, Balakrishnan V, Chan YH, Tong L, Ling Y, Quah BL, et al. Atropine for the treatment of childhood myopia. Ophthalmology 2006;113:2285-91. |
| 113. | Tong L, Huang XL, Koh AL, Zhang X, Tan DT, Chua WH. Atropine for the treatment of childhood myopia: Effect on myopia progression after cessation of atropine. Ophthalmology 2009;116:572-9. |
| 114. | Chia A, Chua WH, Cheung YB, Wong WL, Lingham A, Fong A, et al. Atropine for the treatment of childhood myopia: Safety and efficacy of 0.5%, 0.1%, and 0.01% doses (Atropine for the Treatment of Myopia 2). Ophthalmology 2012;119:347-54. |
| 115. | Kinoshita N, Konno Y, Hamada N, Kanda Y, Shimmura-Tomita M, Kakehashi A. Additive effects of orthokeratology and atropine 0.01% ophthalmic solution in slowing axial elongation in children with myopia: First year results. Jpn J Ophthalmol 2018;62:544-53. |
| 116. | Galvis V, Tello A, Parra MM, Merayo-Lloves J, Larrea J, Julian Rodriguez C, et al. Topical atropine in the control of myopia. Med Hypothesis Discov Innov Ophthalmol 2016;5:78-88. |
| 117. | Wu PC, Chuang MN, Choi J, Chen H, Wu G, Ohno-Matsui K, et al. Update in myopia and treatment strategy of atropine use in myopia control. Eye (Lond) 2019;33:3-13. |
| 118. | Yam JC, Jiang Y, Tang SM, Law AK, Chan JJ, Wong E, et al. Low-concentration atropine for myopia progression (LAMP) study: A randomized, double-blinded, placebo-controlled trial of 0.05%, 0.025%, and 0.01% atropine eye drops in myopia control. Ophthalmology 2019;126:113-24. |
| 119. | Zhao C, Cai C, Ding Q, Dai H. Efficacy and safety of atropine to control myopia progression: A systematic review and meta-analysis. BMC Ophthalmol 2020;20:478. |
| 120. | Fu A, Stapleton F, Wei L, Wang W, Zhao B, Watt K, et al. Effect of low-dose atropine on myopia progression, pupil diameter and accommodative amplitude: Low-dose atropine and myopia progression. Br J Ophthalmol 2020;104:1535-41. |
| 121. | Smith EL 3 rd. Optical treatment strategies to slow myopia progression: Effects of the visual extent of the optical treatment zone. Exp Eye Res 2013;114:77-88. |
| 122. | Smith MJ, Walline JJ. Controlling myopia progression in children and adolescents. Adolesc Health Med Ther 2015;6:133-40. |
| 123. | Fricke T, Tilia D, Tran MA, Hurairah H. Optical interventions to slow the progression of myopia. Community Eye Health 2019;32:19-20. |
| 124. | Akinbinu T, Naidoo KS, Wajuihian SO. Myopia control in the 21 st century: A review of optical methods (2000–2019). Afr Vision Eye Health 2020;79:1-9. |
| 125. | Remón L, Pérez-Merino P, Macedo-de-Araújo RJ, Amorim-de-Sousa AI, González-Méijome JM. Bifocal and multifocal contact lenses for presbyopia and myopia control. J Ophthalmol 2020;2020:8067657. |
| 126. | Young AL, Leung AT, Cheng LL, Law RW, Wong AK, Lam DS. Orthokeratology lens-related corneal ulcers in children: A case series. Ophthalmology 2004;111:590-5. |
|
Search Pubmed for