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Abstract
The epidemic of myopia in urban Asian cities has increased over recent generations and has become a significant public health concern. Considering the potential role of time outdoors in myopia prevention, and the differences in behavioral attitudes of individuals living in Urban East Asian (more indoor-centric) and Western countries, public policies should be developed in different countries accordingly to encourage children to go outdoors to counteract myopia. This is a short manuscript (presented at the International Myopia Conference-2015 by Prof. Seang Mei Saw) about public policies that should be developed to cope with the "myopia epidemic."
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302
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Abstract
Epidemiological studies have demonstrated that spending time outdoors during your childhood is protective against the development of myopia. It has been hypothesized that this protective effect is associated with light-induced increases in retinal dopamine levels, a critical neuromodulator that has long been postulated to be involved in the regulation of ocular growth. This paper, along with the paper entitled "What do animal studies tell us about the mechanism of myopia-protection by light?" discusses the evidence provided by animal models for this hypothesis.
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303
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Zhou Z, Chen T, Wang M, Jin L, Zhao Y, Chen S, Wang C, Zhang G, Wang Q, Deng Q, Liu Y, Morgan IG, He M, Liu Y, Congdon N. Pilot study of a novel classroom designed to prevent myopia by increasing children's exposure to outdoor light. PLoS One 2017; 12:e0181772. [PMID: 28759614 PMCID: PMC5536284 DOI: 10.1371/journal.pone.0181772] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 06/26/2017] [Indexed: 11/18/2022] Open
Abstract
We sought to assess light characteristics and user acceptability of a prototype Bright Classroom (BC), designed to prevent children's myopia by exposing them to light conditions resembling the outdoors. Conditions were measured throughout the school year in the glass-constructed BC, a traditional classroom (TC) and outdoors. Teachers and children completed user questionnaires, and children rated reading comfort at different light intensities. A total of 230 children (mean age 10.2 years, 57.4% boys) and 13 teachers (36.8 years, 15.4% men) completed questionnaires. The median (Inter Quartile Range) light intensity in the BC (2,540 [1,330-4,060] lux) was greater than the TC (477 [245-738] lux, P < 0.001), though less than outdoors (19,500 [8,960-36,000] lux, P < 0.001). A prominent spectral peak at 490-560 nm was present in the BC and outdoors, but less so in the TC. Teachers and children gave higher overall ratings to the BC than TC, and light intensity in the BC in summer and on sunny days (>5,000 lux) was at the upper limit of children's comfort for reading. In summary, light intensity in the BC exceeds TC, and is at the practical upper limit for routine use. Children and teachers prefer the BC.
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Affiliation(s)
- Zhongqiang Zhou
- Henan Eye Institute, Henan Eye Hospital, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, Zhengzhou, China
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Tingting Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- The Department of Ophthalmology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Mengrui Wang
- School of Architecture, South China University of Technology, Guangzhou, China
| | - Ling Jin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Yongyi Zhao
- School of Architecture, South China University of Technology, Guangzhou, China
| | - Shangji Chen
- Guangming Eye Hospital, Yangjiang, People’s Republic of China
| | - Congyao Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Guoshan Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Qilin Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Qiaoming Deng
- School of Architecture, South China University of Technology, Guangzhou, China
| | - Yubo Liu
- School of Architecture, South China University of Technology, Guangzhou, China
| | - Ian G. Morgan
- Research School of Biology, Australian National University, Canberra, Australia
| | - Mingguang He
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Yizhi Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Nathan Congdon
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- ORBIS International, New York, NY, United States of America
- Translational Research for Equitable Eye care, Centre for Public Health, Royal Victoria Hospital, Queen’s University Belfast, Belfast, United Kingdom
- * E-mail:
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304
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Sankaridurg P. Contact lenses to slow progression of myopia. Clin Exp Optom 2017; 100:432-437. [PMID: 28752898 DOI: 10.1111/cxo.12584] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/29/2017] [Accepted: 06/13/2017] [Indexed: 12/28/2022] Open
Abstract
The prevalence of myopia has been steadily rising, with 28 per cent of the global population said to be affected in 2010 and to rise to affect nearly 50 per cent by 2050. Increasing levels of myopia increase the risk of vision impairment and in particular, high myopia is associated with the risk of serious and permanent visual disability due to associated sight-threatening complications. To stem the burden associated with higher levels of myopia, there are efforts to slow the progression of myopia, and several optical and pharmaceutical strategies have been found useful in slowing myopia to varying degrees. More recently, numerous multifocal soft contact lenses and extended depth of focus soft contact lenses (collectively referred to as myopia control contact lenses) were found effective in slowing myopia. As opposed to overnight orthokeratology, myopia control contact lenses are worn during the day and the hypotheses proposed to explain the efficacy of these lenses are generally based on the premise that the stimulus for eye growth is a defocused retinal image with hyperopic blur either centrally or peripherally. Although the individual power profiles of the lenses vary, the contact lens generally incorporates 'positive power' to reduce the hyperopic blur and/or impose myopic defocus or in the case of the extended depth of focus lens, has a power profile designed to optimise retinal image quality for points on or in front of the retina. The use of soft contact lenses as a platform for myopia control offers an exciting and effective avenue to manage myopia but there is a need for further research on issues such as the mechanism underlying control of myopia, improving efficacy with lenses, and understanding rebound on discontinuation. More significantly, although contact lenses are generally safe and improve quality of life in older children, one of the major challenges for improved uptake and acceptance of contact lenses centres on the perceived risk of complications with lens wear. This issue needs to be addressed.
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Affiliation(s)
- Padmaja Sankaridurg
- Brien Holden Vision Institute, Sydney, New South Wales, Australia.,School of Optometry and Vision Science, The University of New South Wales, Sydney, New South Wales, Australia
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305
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Kearney S, O'Donoghue L, Pourshahidi LK, Cobice D, Saunders KJ. Myopes have significantly higher serum melatonin concentrations than non-myopes. Ophthalmic Physiol Opt 2017; 37:557-567. [PMID: 28721695 DOI: 10.1111/opo.12396] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 05/16/2017] [Indexed: 12/13/2022]
Abstract
PURPOSE Experimental animal models of myopia demonstrate that higher melatonin (Mel) and lower dopamine (DA) concentrations actively promote axial elongation. This study explored the association between myopia and serum concentrations of DA and Mel in humans. METHODS Morning serum concentrations of DA and Mel were measured by solid phase extraction-liquid chromatography-tandem mass spectrometry from 54 participants (age 19.1 ± 0.81 years) in September/October 2014 (phase 1) and March/April 2016 (phase 2). Axial length (AL), corneal radii (CR) and spherical equivalent refraction (SER) were also recorded. Participants were defined as myopic if non-cycloplegic spherical equivalent refractive error ≤-0.50 DS at phase 1. RESULTS Nine participants were lost to follow up. Mel concentrations were measurable for all myopes (phase 1 n = 25, phase 2 n = 22) and non-myopes (phase 1 n = 29, phase 2 n = 23). SER did not change significantly between phases (p = 0.51). DA concentrations were measurable for fewer myopes (phase 1 n = 13, phase 2 n = 12) and non-myopes (phase 1 n = 23, phase 2 n = 16). Myopes exhibited significantly higher Mel concentrations than non-myopes at phase 1 (Median difference: 10 pg mL-1 , p < 0.001) and at phase 2 (Median difference: 7.3 pg mL-1 , p < 0.001) and lower DA concentrations at phase 2 (Median difference: 4.7 pg mL-1 , p = 0.006). Mel concentrations were positively associated with more negative SER (all r ≥ -0.53, all p < 0.001), longer AL (all r ≥ 0.37, all p ≤ 0.008) and higher AL/CR ratio (all r ≥ 0.51, all p < 0.001). CONCLUSION This study reports for the first time in humans that myopes exhibit higher serum Mel concentrations than non-myopes. This may indicate a role for light exposure and circadian rhythm in the human myopic growth mechanism. Further research should focus on younger cohorts exhibiting more dynamic myopic progression and explore the profile of these neurochemicals alongside evaluation of sleep patterns in myopic and non-myopic groups.
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Affiliation(s)
- Stephanie Kearney
- Optometry and Vision Science Research Group, University of Ulster, Coleraine, UK
| | - Lisa O'Donoghue
- Optometry and Vision Science Research Group, University of Ulster, Coleraine, UK
| | - L Kirsty Pourshahidi
- Northern Ireland Centre for Food and Health (NICHE), University of Ulster, Coleraine, UK
| | - Diego Cobice
- Metabolomics and Proteomics Core Facility Unit, Biomedical Research Institute, University of Ulster, Coleraine, UK
| | - Kathryn J Saunders
- Optometry and Vision Science Research Group, University of Ulster, Coleraine, UK
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306
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Terasaki H, Yamashita T, Yoshihara N, Kii Y, Sakamoto T. Association of lifestyle and body structure to ocular axial length in Japanese elementary school children. BMC Ophthalmol 2017; 17:123. [PMID: 28697750 PMCID: PMC5506696 DOI: 10.1186/s12886-017-0519-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 07/07/2017] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The purpose of this study is to determine whether the lifestyle and body stature are significantly associated with the axial length (AL) of the eyes of Japanese third grade students. METHODS A prospective, cross sectional, observational study was performed on 122 third grade students consisting of 61 boys and 61 girls ages 8 to 9 years. The AL, body height, body weight, and body mass index (BMI) were measured. The lifestyle was determined by activities such as the daily duration of indoor studying, television viewing, use of computers and smart phones, outdoor activity time, bed time, Japanese or Western dietary habits, and parental myopia were investigated by a questionnaire with three or five grade levels. The relationship between AL and the questionnaire variables were analyzed by Spearman's correlation analyses. RESULTS Westernized dietary habits (r = -0.24, P = 0.01), duration of computer and smart phone use (r = 0.24, P = 0.008), parental myopia (r = 0.39, P < 0.001), body weight (r = 0.26, P = 0.005), and BMI (r = 0.23, P = 0.011) were significantly correlated with the AL. Multiple logistic regression analyses showed that the sex [r = -0.48; 95% confidence interval (CI) -0.80 to -0.17, P = 0.003], body weight (r = 0.04; 95% CI 0.02 to 0.07, P = 0.038), westernized dietary habits (r = -0.30; 95% CI -0.55 to -0.05, P = 0.021), and parental myopia (r = 0.40; 95% CI 0.20 to 0.61, P < 0.001) were significantly and independently correlated with the AL. CONCLUSIONS The body weight and parental myopia and westernized dietary habits are factors significantly associated with myopia. Changing from Japanese food style to westernized food style might increase the risk of progression of school myopia.
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Affiliation(s)
- Hiroto Terasaki
- Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Takehiro Yamashita
- Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Naoya Yoshihara
- Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yuya Kii
- Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Taiji Sakamoto
- Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
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307
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Wang YR, Bian HL, Wang Q. Atropine 0.5% eyedrops for the treatment of children with low myopia: A randomized controlled trial. Medicine (Baltimore) 2017; 96:e7371. [PMID: 28682887 PMCID: PMC5502160 DOI: 10.1097/md.0000000000007371] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 05/31/2017] [Accepted: 06/06/2017] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND This study aimed to assess the efficacy and safety of atropine 0.5% eyedrops (ATE) for the treatment of children with low myopia (LM). METHODS In this study, a total of 126 children with LM were randomly divided into an intervention group (administered 0.5% ATE) and a control group (administered a placebo), with 63 children in each group. The outcome measurements were changes in the spherical equivalent (SE), and axial length (AL), as well as adverse events (AEs). RESULTS Compared with placebo, administration of 0.5% ATE led to less progression in LM, as measured by SE, and less increase in AL (P < .01). In addition, no serious AEs occurred in both the groups. CONCLUSION About 0.5% ATE was efficacious and safe for controlling myopia in children with LM.
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Affiliation(s)
- Yan-rong Wang
- Department of Ophthalmology, The People's Hospital of Yan’an
| | - Hong-Li Bian
- Department of Ophthalmology, Affiliated Hospital of Yan’an University, Yan’an, China
| | - Qi Wang
- Department of Ophthalmology, The People's Hospital of Yan’an
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308
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Verkicharla PK, Ramamurthy D, Nguyen QD, Zhang X, Pu SH, Malhotra R, Ostbye T, Lamoureux EL, Saw SM. Development of the FitSight Fitness Tracker to Increase Time Outdoors to Prevent Myopia. Transl Vis Sci Technol 2017; 6:20. [PMID: 28660095 PMCID: PMC5477631 DOI: 10.1167/tvst.6.3.20] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 03/19/2017] [Indexed: 11/25/2022] Open
Abstract
Purpose To develop a fitness tracker (FitSight) to encourage children to increase time spent outdoors. To evaluate the wear pattern for this tracker and outdoor time pattern by estimating light illumination levels among children. Methods The development of the FitSight fitness tracker involved the designing of two components: (1) the smartwatch with custom-made FitSight watch application (app) to log the instant light illuminance levels the wearer is exposed to, and (2) a companion smartphone app that synchronizes the time outdoors recorded by the smartwatch to smartphone via Bluetooth communication. Smartwatch wear patterns and tracker-recorded daily light illuminance levels data were gathered over 7 days from 23 Singapore children (mean ± standard deviation age: 9.2 ± 1.4 years). Feedback about the tracker was obtained from 14 parents using a three-level rating scale: very poor/poor/good. Results Of the 14 parents, 93% rated the complete “FitSight fitness tracker” as good and 64% rated its wearability as good. While 61% of 23 children wore the watch on all study days (i.e., 0 nonwear days), 26% had 1 nonwear day, and 4.5% children each had 3, 4, and 5 nonwear days, respectively. On average, children spent approximately 1 hour in light levels greater than 1000 lux on weekdays and 1.3 hours on weekends (60 ± 46 vs. 79 ± 53 minutes, P = 0.19). Mean number of outdoor “spurts” (light illuminance levels >1000 lux) per day was 8 ± 3 spurts with spurt duration of 34 ± 32 minutes. Conclusion The FitSight tracker with its novel features may motivate children to increase time outdoors and play an important role in supplementing community outdoor programs to prevent myopia. Translational Relevance If the developed noninvasive, wearable, smartwatch-based fitness tracker, FitSight, promotes daytime outdoor activity among children, it will be beneficial in addressing the epidemic of myopia.
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Affiliation(s)
| | - Dharani Ramamurthy
- Singapore Eye Research Institute, The Academia, Singapore.,National University of Singapore, Singapore
| | | | - Xinquan Zhang
- Agency for Science, Technology and Research (ASTAR), Singapore
| | - Suan-Hui Pu
- University of Southampton, Malaysia Campus, Johor, Malaysia
| | | | | | | | - Seang-Mei Saw
- Singapore Eye Research Institute, The Academia, Singapore.,National University of Singapore, Singapore
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309
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Shah RL, Huang Y, Guggenheim JA, Williams C. Time Outdoors at Specific Ages During Early Childhood and the Risk of Incident Myopia. Invest Ophthalmol Vis Sci 2017; 58:1158-1166. [PMID: 28245296 PMCID: PMC5341622 DOI: 10.1167/iovs.16-20894] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Purpose Time outdoors during childhood is negatively associated with incident myopia. Consequently, additional time outdoors has been suggested as a public health intervention to reduce the prevalence of myopia. We investigated whether there were specific ages during early childhood when the time outdoors versus incident myopia association was strongest. Methods Children participating in the Avon Longitudinal Study of Parents and Children (ALSPAC) were studied from age 2 to 15 years. Parentally reported time outdoors and time spent reading were assessed longitudinally in early childhood (ages 2, 3, 4, 5, 7, and 9 years). Noncycloplegic autorefraction was carried out longitudinally in later childhood (ages 10, 11, 12, and 15 years). Information was available for 2833 participants. Cox proportional hazards regression was used to test for association between time outdoors and incident myopia. Results From 3 years of age onward, greater time outdoors was associated with a reduced risk of incident myopia. The hazard ratio for myopia changed progressively from 0.90 (95% CI 0.83–0.98, P = 0.012) at age 3 years, to 0.86 (95% CI 0.78–0.93, P = 0.001) at age 9 years, for each additional SD of time spent outdoors per day. These associations were independent of two major risk factors for myopia: time reading and number of myopic parents. Conclusions Additional time spent outdoors across the 3 to 9 years age range was associated with a reduced incidence of myopia between ages 10 and 15 years. There was a trend for the association to increase toward the older end of the 3 to 9 years range.
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Affiliation(s)
- Rupal L Shah
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom
| | - Yu Huang
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom 2School of Optometry, Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Jeremy A Guggenheim
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom
| | - Cathy Williams
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom
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310
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Li Y, Liu J, Qi P. The increasing prevalence of myopia in junior high school students in the Haidian District of Beijing, China: a 10-year population-based survey. BMC Ophthalmol 2017; 17:88. [PMID: 28606071 PMCID: PMC5468969 DOI: 10.1186/s12886-017-0483-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 05/31/2017] [Indexed: 11/12/2022] Open
Abstract
Background Myopia is a leading cause of preventable blindness. Although, multiple cross-sectional epidemiological studies have confirmed that there is a high prevalence of myopia in high school-aged students in China. However, few longitudinal studies have been performed to assess junior high school students. In the present study, we investigate changes in the prevalence of myopia in third year junior high school (grade 9) students in the Haidian District of Beijing, China, from 2006 to 2015. Methods A retrospective, longitudinal cohort study was performed over 10 years. A total of 37,424 third-year middle school (grade 9) students from 8 junior high schools in Haidian district, Beijing, were included. Participants underwent a comprehensive ophthalmic examination in which they were evaluated using autorefraction under cycloplegia and submitted to retinoscopy to assess accuracy. According to the spherical equivalent refraction (SER) of the right eye, subjects were separated into the following groups: non-myopia, −0.5 ≤ SER diopters (D); low myopia, −3.0 ≤ SER < −0.5 D; moderate myopia, −6.0 ≤ SER < −3.0 D; and high myopia, SER > −6.0 D. The following characteristics were measured: refractive error; the proportion of subjects with non- myopia, low myopia, moderate myopia and high myopia; and the difference in the prevalence of myopia between male and female subjects. Results From 2006 to 2015, the prevalence of non-myopia (from 44.05% to 34.52%) and low myopia (from 32.27% to 20.73%) decreased, while the prevalence of moderate myopia (from 19.72% to 38.06%) and high myopia (from 3.96% to 6.69%) significantly increased. For refractive error, the worse eye was −2.23 ± 2.42 D (median, −1.75; range − 12.75 to +8.50) in 2006 and −3.13 ± 2.66 D (median, −2.75; range − 12.75 to +8.50) in 2015. When the entire population was considered, the overall prevalence of myopia increased from 55.95% in 2005 to 65.48% in 2015. There was a significant positive relationship between the year and the prevalence of myopia in both girls and boys. Girls were more likely than boys to have myopia (odds ratio, 1.43 [95% CI, 1.14–1.96]), especially moderate myopia, and the prevalence of moderate and high myopia were higher in girls than in boys. Conclusions During the last 10 years, the prevalence of myopia significantly increased on an annual basis among third-year junior high school students in the Haidian District of Beijing, China. The total prevalence of myopia was significantly higher in girl than in boy participants. The refractive status of this age group deserves particular attention. Electronic supplementary material The online version of this article (doi:10.1186/s12886-017-0483-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yan Li
- Department of Ophthalmology, College of Optometry, Peking University Health Science Center; Center of Optometry, Peking University People's Hospital; Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, Beijing, 100044, China
| | - Jia Liu
- Department of Ophthalmology, College of Optometry, Peking University Health Science Center; Center of Optometry, Peking University People's Hospital; Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, Beijing, 100044, China. .,Key Laboratory of Vision Loss and Restoration, Ministry of Education, Department of Ophthalmology, Peking University People's Hospital, Xizhimen South Street 11, Xi Cheng District, Beijing, 100044, China.
| | - Pengcheng Qi
- Department of Ophthalmology, College of Optometry, Peking University Health Science Center; Center of Optometry, Peking University People's Hospital; Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, Beijing, 100044, China
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311
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Zhou X, Pardue MT, Iuvone PM, Qu J. Dopamine signaling and myopia development: What are the key challenges. Prog Retin Eye Res 2017; 61:60-71. [PMID: 28602573 DOI: 10.1016/j.preteyeres.2017.06.003] [Citation(s) in RCA: 182] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Revised: 05/23/2017] [Accepted: 06/05/2017] [Indexed: 01/11/2023]
Abstract
In the face of an "epidemic" increase in myopia over the last decades and myopia prevalence predicted to reach 2.5 billion people by the end of this decade, there is an urgent need to develop effective and safe therapeutic interventions to slow down this "myopia booming" and prevent myopia-related complications and vision loss. Dopamine (DA) is an important neurotransmitter in the retina and mediates diverse functions including retina development, visual signaling, and refractive development. Inspired by the convergence of epidemiological and animal studies in support of the inverse relationship between outdoor activity and risk of developing myopia and by the close biological relationship between light exposure and dopamine release/signaling, we felt it is timely and important to critically review the role of DA in myopia development. This review will revisit several key points of evidence for and against DA mediating light control of myopia: 1) the causal role of extracellular retinal DA levels, 2) the mechanism and action of dopamine D1 and D2 receptors and 3) the roles of cellular/circuit retinal pathways. We examine the experiments that show causation by altering DA, DA receptors and visual pathways using pharmacological, transgenic, or visual environment approaches. Furthermore, we critically evaluate the safety issues of a DA-based treatment strategy and some approaches to address these issues. The review identifies the key questions and challenges in translating basic knowledge on DA signaling and myopia from animal studies into effective pharmacological treatments for myopia in children.
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Affiliation(s)
- Xiangtian Zhou
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, 270 Xueyuan Road, Wenzhou, Zhejiang 325003, China; State Key Laboratory of Ophthalmology, Optometry and Vision Science. 270 Xueyuan Road, Wenzhou, Zhejiang, 325003, China
| | - Machelle T Pardue
- Department of Biomedical Engineering, Georgia Institute of Technology, 313 Ferst Dr, Atlanta, GA 30332, United States; Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center, 1670 Clairmont Rd, Decatur, GA 30033, United States
| | - P Michael Iuvone
- Department of Ophthalmology, Emory University School of Medicine, 1365B Clifton Rd NE, Atlanta, GA 30322, United States; Department of Pharmacology, Emory University School of Medicine, 1365B Clifton Rd NE, Atlanta, GA 30322, United States
| | - Jia Qu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, 270 Xueyuan Road, Wenzhou, Zhejiang 325003, China; State Key Laboratory of Ophthalmology, Optometry and Vision Science. 270 Xueyuan Road, Wenzhou, Zhejiang, 325003, China.
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312
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Stone RA, Cohen Y, McGlinn AM, Davison S, Casavant S, Shaffer J, Khurana TS, Pardue MT, Iuvone PM. Development of Experimental Myopia in Chicks in a Natural Environment. Invest Ophthalmol Vis Sci 2017; 57:4779-89. [PMID: 27618415 PMCID: PMC5024671 DOI: 10.1167/iovs.16-19310] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Purpose The hypothesis that outdoor exposure might protect against myopia has generated much interest, although available data find only modest clinical efficacy. We tested the effect of outdoor rearing on form-deprivation myopia in chicks, a myopia model markedly inhibited by high-intensity indoor laboratory lighting. Methods Unilaterally goggled cohorts of White Leghorn chicks were maintained in a species-appropriate, outdoor rural setting during daylight hours to the extent permitted by weather. Control chicks were reared indoors with incandescent lighting. Besides ocular refraction and ultrasound, we determined dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) content in retina and vitreous and measured mRNA expression levels of selected clock and circadian rhythm-related genes in the retina/RPE. Results Myopia developed in the goggled eyes of all cohorts. Whereas outdoor rearing lessened myopia by 44% at 4 days, a protective effect was no longer evident at 11 days. Outdoor rearing had no consistent effect on retinal or vitreous content of dopamine or DOPAC. Conforming to prior data on form-deprivation myopia, retina and vitreous levels of DOPAC were reduced in goggled eyes. Compared with contralateral eyes, the retinal expression of clock and circadian rhythm-related genes was modestly altered in myopic eyes of chicks reared indoors or outdoors. Conclusions Outdoor rearing of chicks induces only a partial decrease of goggle-induced myopia that is not maintained, without evidence that retinal dopamine metabolism accounts for the partial myopia inhibition under these outdoor conditions. Although modest, alterations in retinal gene expression suggest that studying circadian signals might be informative for understanding refractive mechanisms.
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Affiliation(s)
- Richard A Stone
- Department of Ophthalmology University of Pennsylvania School of Medicine, Scheie Eye Institute, Philadelphia, Pennsylvania, United States
| | - Yuval Cohen
- Department of Ophthalmology University of Pennsylvania School of Medicine, Scheie Eye Institute, Philadelphia, Pennsylvania, United States
| | - Alice M McGlinn
- Department of Ophthalmology University of Pennsylvania School of Medicine, Scheie Eye Institute, Philadelphia, Pennsylvania, United States
| | - Sherrill Davison
- Laboratory of Avian Medicine and Pathology, University of Pennsylvania School of Veterinary Medicine, New Bolton Center, Kennett Square, Pennsylvania, United States
| | - Susan Casavant
- Laboratory of Avian Medicine and Pathology, University of Pennsylvania School of Veterinary Medicine, New Bolton Center, Kennett Square, Pennsylvania, United States
| | - James Shaffer
- Department of Ophthalmology University of Pennsylvania School of Medicine, Scheie Eye Institute, Philadelphia, Pennsylvania, United States
| | - Tejvir S Khurana
- Department of Physiology and Pennsylvania Muscle Institute, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States
| | - Machelle T Pardue
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States 5Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center, Decatur, Georgia, United States
| | - P Michael Iuvone
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, United States 7Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia, United States
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Guo Y, Liu LJ, Tang P, Lv YY, Feng Y, Xu L, Jonas JB. 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. [PMID: 28448513 PMCID: PMC5407804 DOI: 10.1371/journal.pone.0175921] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 04/02/2017] [Indexed: 11/28/2022] Open
Abstract
Purpose To investigate factors associated with ocular axial elongation and myopia progression during a 4-year follow-up in primary school children in Beijing. Methods This school-based study included 382 grade-1 children at baseline in 2011 (age:6.3±0.4 years) with 305 (79.8%) returning for the follow-up examination in 2015. At baseline and in yearly follow-up examinations, the children underwent a comprehensive eye examination including auto-refractometry, ocular biometry with measurement of axial length, and fundus photography. The parents underwent a standardized interview. Results During the study period, the mean axial length elongated by 1.15±0.56mm in boys and 1.10±0.63mm in girls. At baseline and at the end of follow-up, axial length was significantly (P<0.001) longer in boys, with no difference (P = 0.50) between genders in axial elongation. In multivariate analysis, greater axial elongation was associated (regression coefficient r2:0.15) with less time spent outdoors (P = 0.004; standardized coefficient beta: -0.22), more time spent indoors with studying (P = 0.02; beta: 0.18) and paternal myopia (P = 0.03; beta: 0.16). Larger increases in the axial length/anterior corneal curvature (AL/CC) ratio were associated (r2:0.09) with less time spent outdoors (PP = 0.003; beta: -0.22) and maternal myopia (PP = 0.02; beta: 0.18). Conclusions Myopic axial elongation during a 4-year follow-up was associated with shorter time spent outdoors and longer time spent indoors studying and with parental myopia. Other factors such as level of paternal education, family income, gender and region of habitation were significantly associated with axial elongation and with myopia progression only in univariate analysis.
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Affiliation(s)
- Yin Guo
- Beijing Institute of Ophthalmology, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Tongren Eye Care Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Li Juan Liu
- Beijing Institute of Ophthalmology, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Ping Tang
- Tongren Eye Care Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Yan Yun Lv
- Tongren Eye Care Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Yi Feng
- Tongren Eye Care Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Liang Xu
- Beijing Institute of Ophthalmology, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- * E-mail:
| | - Jost B. Jonas
- Beijing Institute of Ophthalmology, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Department of Ophthalmology, Medical Faculty Mannheim of the Ruprecht-Karls-University Heidelberg, Mannheim, Germany
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316
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Williams KM, Hysi PG, Yonova-Doing E, Mahroo OA, Snieder H, Hammond CJ. Phenotypic and genotypic correlation between myopia and intelligence. Sci Rep 2017; 7:45977. [PMID: 28383074 PMCID: PMC5382686 DOI: 10.1038/srep45977] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 03/07/2017] [Indexed: 01/13/2023] Open
Abstract
Myopia, or near-sightedness, is our most common eye condition and the prevalence is increasing globally. Visual impairment will occur if uncorrected, whilst high myopia causes sight-threatening complications. Myopia is associated with higher intelligence. As both are heritable, we set out to examine whether there is a genetic correlation between myopia and intelligence in over 1,500 subjects (aged 14-18 years) from a twin birth cohort. The phenotypic correlation between refractive error and intelligence was -0.116 (p < 0.01) - the inverse correlation due to the fact that myopia is a negative refractive error. Bivariate twin modeling confirmed both traits were heritable (refractive error 85%, intelligence 47%) and the genetic correlation was -0.143 (95% CI -0.013 to -0.273). Of the small phenotypic correlation the majority (78%) was explained by genetic factors. Polygenic risk scores were constructed based on common genetic variants identified in previous genome-wide association studies of refractive error and intelligence. Genetic variants for intelligence and refractive error explain some of the reciprocal variance, suggesting genetic pleiotropy; in the best-fit model the polygenic score for intelligence explained 0.99% (p = 0.008) of refractive error variance. These novel findings indicate shared genetic factors contribute significantly to the covariance between myopia and intelligence.
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Affiliation(s)
- Katie M. Williams
- Department of Ophthalmology, King’s College London, 3rd Floor Block D South Wing, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, UK
- Department of Twin Research & Genetic Epidemiology, King’s College London, 3rd Floor Block D South Wing, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, UK
| | - Pirro G. Hysi
- Department of Twin Research & Genetic Epidemiology, King’s College London, 3rd Floor Block D South Wing, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, UK
| | - Ekaterina Yonova-Doing
- Department of Twin Research & Genetic Epidemiology, King’s College London, 3rd Floor Block D South Wing, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, UK
| | - Omar A. Mahroo
- Department of Ophthalmology, King’s College London, 3rd Floor Block D South Wing, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, UK
| | - Harold Snieder
- Unit of Genetic Epidemiology & Bioinformatics, Department of Epidemiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ, The Netherlands
| | - Christopher J. Hammond
- Department of Ophthalmology, King’s College London, 3rd Floor Block D South Wing, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, UK
- Department of Twin Research & Genetic Epidemiology, King’s College London, 3rd Floor Block D South Wing, St Thomas’ Hospital, Westminster Bridge Road, London, SE1 7EH, UK
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Hsu CC, Huang N, Lin PY, Fang SY, Tsai DC, Chen SY, Tsai CY, Woung LC, Chiou SH, Liu CJL. Risk factors for myopia progression in second-grade primary school children in Taipei: a population-based cohort study. Br J Ophthalmol 2017; 101:1611-1617. [PMID: 28315834 DOI: 10.1136/bjophthalmol-2016-309299] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 02/28/2017] [Accepted: 03/08/2017] [Indexed: 11/03/2022]
Abstract
PURPOSE To evaluate the 1-year progression of myopia and associated risk factors in second-grade primary school children. METHODS The myopia investigation study in Taipei provided semiannual visual acuity testing and cycloplegic refraction for all second-grade primary school children (mean age: 7.49 years) in Taipei who provided parental consent. A questionnaire was distributed to the participants' parents before the first and third examinations. We evaluated 1-year follow-up data for children noted to have myopia on the first examination. Multinomial logistic regression models were applied to assess risk factors associated with myopia progression. Myopia progression was categorised, based on the change in spherical equivalent (ΔSE) over 1 year, as slow (ΔSE>-0.5 dioptres (D)), moderate (-1.0 D<ΔSE≤-0.5 D) or fast (ΔSE≤-1.0 D). Of the 4214 myopic children, data were analysed for 3256 (77.3%) who completed the 1-year follow-up evaluation. RESULTS The baseline SE was -1.43±1.1 D. The average ΔSE was -0.42±0.85 D, with 46.96%, 28.50% and 24.54% of the study subjects showing slow, moderate and fast myopia progression, respectively. When compared with slow myopia progression, fast myopia progression was associated with a greater myopic SE at baseline (OR: 0.67, 95% CI: 0.61 to 0.72) and a shorter eye-object distance when doing near work (OR: 1.45, 95% CI: 1.18 to 1.78). More outdoor activity time and self-reported cycloplegic treatment were not associated with slow myopia progression. CONCLUSIONS Children with fast annual myopia progression were more myopic at baseline and had a shorter reading distance. Our study results highlight the importance of having children keep a proper reading distance.
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Affiliation(s)
- Chih-Chien Hsu
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.,Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Nicole Huang
- Institute of Hospital and Health Care Administration, National Yang-Ming University, Taipei, Taiwan
| | - Pei-Yu Lin
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan.,Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Shao-You Fang
- Institution of Public Health, National Yang-Ming University, Taipei, Taiwan
| | - Der-Chong Tsai
- Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan.,Department of Ophthalmology, National Yang-Ming University Hospital, I-Lan, Taiwan
| | - Shing-Yi Chen
- Department of Health, Taipei City Government, Taipei, Taiwan
| | - Ching-Yao Tsai
- Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan.,Department of Ophthalmology, Taipei City Hospital, Taipei, Taiwan
| | - Lin-Chung Woung
- Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan.,Department of Ophthalmology, Taipei City Hospital, Taipei, Taiwan
| | - Shih-Hwa Chiou
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.,Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan.,Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan.,Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan.,Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan
| | - Catherine Jui-Ling Liu
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan.,Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan
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318
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Effect of pregnancy in myopia progression: the SUN cohort. Eye (Lond) 2017; 31:1085-1092. [PMID: 28304386 DOI: 10.1038/eye.2017.24] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 01/31/2017] [Indexed: 01/22/2023] Open
Abstract
PurposePrevious studies have suggested that pregnancy may induce myopia progression. However, no longitudinal study with a large sample size and long-term follow-up has assessed this association. Our objective was to investigate whether pregnancy was related to mid- or long-term myopic refraction changes.Patients and methodsA prospective study was conducted in a Mediterranean cohort. The study included 10 401 women (20-50 years old) from the SUN Project. SUN project is a multipurpose, prospective, and dynamic cohort of university graduates conducted in Spain. The recruitment of participants started in 1999 and it is permanently open. All participants in this cohort had university studies. Participants were followed up for a period of up to 14 years, and pregnancy and refractive changes were assessed through baseline and biennial questionnaires. Pregnancies and myopia were repeatedly assessed in each biennial follow-up questionnaire during a total of 14 years of follow-up.ResultsPregnancy was inversely associated with the risk of myopia development or progression during each of the 2 years periods, with fully adjusted hazard ratio=0.61; (95% confidence interval=0.49-0.75) after adjusting for known potential confounders.ConclusionTo our knowledge this is the first large-longitudinal assessment in young adult women, showing that pregnancy is inversely associated with myopia development or progression. Further studies are needed to confirm these epidemiological findings.
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319
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Bio-environmental factors associated with myopia: An updated review. ACTA ACUST UNITED AC 2017; 92:307-325. [PMID: 28162831 DOI: 10.1016/j.oftal.2016.11.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 11/27/2016] [Accepted: 11/29/2016] [Indexed: 12/12/2022]
Abstract
Experimental studies in animals, as well as observational and intervention studies in humans, seem to support the premise that the development of juvenile myopia is promoted by a combination of the effect of genetic and environmental factors, with a complex interaction between them. The very rapid increase in myopia rates in some parts of the world, such as Southeast Asia, supports a significant environmental effect. Several lines of evidence suggest that humans might respond to various external factors, such as increased activity in near vision, increased educational pressure, decreased exposure to sunlight outdoors, dietary changes (including increased intake of carbohydrates), as well as low light levels indoors. All these factors could be associated with a higher prevalence of myopia.
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320
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Abstract
Myopia is not a simple refractive error, but an eyesight-threatening disease. There is a high prevalence of myopia, 80% to 90%, in young adults in East Asia; myopia has become the leading cause of blindness in this area. As the myopic population increases globally, the severity of its impact is predicted. Approximately one fifth of the myopic population has high myopia (≥-6 diopters), which results in irreversible vision loss such as retinal detachment, choroidal neovascularization, cataracts, glaucoma, and macular atrophy. The increasing prevalence of school myopia in the past few decades may be a result of gene-environment interactions. However, earlier school myopia onset would accompany faster myopia progression and greater risk of high myopia later in life. Recently, there have been effective interventions to delay the onset of myopia, such as outdoor activity and decreasing the duration of near work. Hyperopia (≤0.5 diopters) is a predictor of myopia. Pharmacological agents and optic interventions such as low-concentration atropine and orthokeratology may slow progression in myopic children. Novel surgeries and anti-vascular endothelial growth factor drugs could deal with some myopic complications. From available evidence, the prevention, control, and treatment of myopia seem to be promising. However, to reduce the impact of myopia in future decades, more work and effort are still needed, including that by governments and intercountry eye health organizations.
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Affiliation(s)
- Pei-Chang Wu
- From the Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan, Republic of China
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321
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Rose KA, French AN, Morgan IG. Environmental Factors and Myopia: Paradoxes and Prospects for Prevention. Asia Pac J Ophthalmol (Phila) 2017; 5:403-410. [PMID: 27898443 DOI: 10.1097/apo.0000000000000233] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
The prevalence of myopia in developed countries in East and Southeast Asia has increased to more than 80% in children completing schooling, whereas that of high myopia has increased to 10%-20%. This poses significant challenges for correction of refractive errors and the management of pathological high myopia. Prevention is therefore an important priority. Myopia is etiologically heterogeneous, with a low level of myopia of clearly genetic origins that appears without exposure to risk factors. The big increases have occurred in school myopia, driven by increasing educational pressures in combination with limited amounts of time spent outdoors. The rise in prevalence of high myopia has an unusual pattern of development, with increases in prevalence first appearing at approximately age 11. This pattern suggests that the increasing prevalence of high myopia is because of progression of myopia in children who became myopic at approximately age 6 or 7 because age-specific progression rates typical of East Asia will take these children to the threshold for high myopia in 5 to 6 years. This high myopia seems to be acquired, having an association with educational parameters, whereas high myopia in previous generations tended to be genetic in origin. Increased time outdoors can counter the effects of increased nearwork and reduce the impact of parental myopia, reducing the onset of myopia, and this approach has been validated in 3 randomized controlled trials. Other proposed risk factors need further work to demonstrate that they are independent and can be modified to reduce the onset of myopia.
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Affiliation(s)
- Kathryn Ailsa Rose
- From the *Discipline of Orthoptics, Graduate School of Health, University of Technology Sydney, Ultimo, New South Wales; †Research School of Biology, Australian National University, Canberra, Australian Capital Territory, Australia; and ‡State Key Laboratory of Ophthalmology and Division of Preventive Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
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322
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Abstract
Light and optical techniques have made profound impacts on modern
medicine, with numerous lasers and optical devices being currently used in
clinical practice to assess health and treat disease. Recent advances in
biomedical optics have enabled increasingly sophisticated technologies —
in particular those that integrate photonics with nanotechnology, biomaterials
and genetic engineering. In this Review, we revisit the fundamentals of
light–matter interactions, describe the applications of light in
imaging, diagnosis, therapy and surgery, overview their clinical use, and
discuss the promise of emerging light-based technologies.
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Affiliation(s)
- Seok Hyun Yun
- Wellman Center for Photomedicine, Massachusetts General Hospital, 65 Landsdowne Street, Cambridge, MA 02139, USA.,Department of Dermatology, Harvard Medical School, 25 Shattuck Street, Boston, MA 02115.,Harvard-MIT Health Sciences and Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Sheldon J J Kwok
- Wellman Center for Photomedicine, Massachusetts General Hospital, 65 Landsdowne Street, Cambridge, MA 02139, USA.,Harvard-MIT Health Sciences and Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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323
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Pan CW, Qian DJ, Saw SM. Time outdoors, blood vitamin D status and myopia: a review. Photochem Photobiol Sci 2017; 16:426-432. [DOI: 10.1039/c6pp00292g] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Myopia is a major public health concern throughout the world but whether vitamin D played a role in myopia development remains unknown.
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Affiliation(s)
- Chen-Wei Pan
- Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases
- School of Public Health
- Medical College of Soochow University
- Suzhou
- China
| | - Deng-Juan Qian
- Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases
- School of Public Health
- Medical College of Soochow University
- Suzhou
- China
| | - Seang-Mei Saw
- Singapore Eye Research Institute
- Singapore
- Saw Swee Hock School of Public Health
- National University of Singapore
- Singapore
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324
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Ward AH, Siegwart JT, Frost MR, Norton TT. Intravitreally-administered dopamine D2-like (and D4), but not D1-like, receptor agonists reduce form-deprivation myopia in tree shrews. Vis Neurosci 2017; 34:E003. [PMID: 28304244 PMCID: PMC5567805 DOI: 10.1017/s0952523816000195] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We examined the effect of intravitreal injections of D1-like and D2-like dopamine receptor agonists and antagonists and D4 receptor drugs on form-deprivation myopia (FDM) in tree shrews, mammals closely related to primates. In eleven groups (n = 7 per group), we measured the amount of FDM produced by monocular form deprivation (FD) over an 11-day treatment period. The untreated fellow eye served as a control. Animals also received daily 5 µL intravitreal injections in the FD eye. The reference group received 0.85% NaCl vehicle. Four groups received a higher, or lower, dose of a D1-like receptor agonist (SKF38393) or antagonist (SCH23390). Four groups received a higher, or lower, dose of a D2-like receptor agonist (quinpirole) or antagonist (spiperone). Two groups received the D4 receptor agonist (PD168077) or antagonist (PD168568). Refractions were measured daily; axial component dimensions were measured on day 1 (before treatment) and day 12. We found that in groups receiving the D1-like receptor agonist or antagonist, the development of FDM and altered ocular component dimensions did not differ from the NaCl group. Groups receiving the D2-like receptor agonist or antagonist at the higher dose developed significantly less FDM and had shorter vitreous chambers than the NaCl group. The D4 receptor agonist, but not the antagonist, was nearly as effective as the D2-like agonist in reducing FDM. Thus, using intravitreally-administered agents, we did not find evidence supporting a role for the D1-like receptor pathway in reducing FDM in tree shrews. The reduction of FDM by the dopamine D2-like agonist supported a role for the D2-like receptor pathway in the control of FDM. The reduction of FDM by the D4 receptor agonist, but not the D4 antagonist, suggests an important role for activation of the dopamine D4 receptor in the control of axial elongation and refractive development.
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Affiliation(s)
- Alexander H. Ward
- Genetics, Genomics and Bioinformatics Theme, University of Alabama at Birmingham, Birmingham, AL 35294
| | - John T. Siegwart
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Michael R. Frost
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Thomas T. Norton
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL 35294
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325
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Violet Light Exposure Can Be a Preventive Strategy Against Myopia Progression. EBioMedicine 2016; 15:210-219. [PMID: 28063778 PMCID: PMC5233810 DOI: 10.1016/j.ebiom.2016.12.007] [Citation(s) in RCA: 110] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 12/13/2016] [Accepted: 12/13/2016] [Indexed: 01/10/2023] Open
Abstract
Prevalence of myopia is increasing worldwide. Outdoor activity is one of the most important environmental factors for myopia control. Here we show that violet light (VL, 360–400 nm wavelength) suppresses myopia progression. First, we confirmed that VL suppressed the axial length (AL) elongation in the chick myopia model. Expression microarray analyses revealed that myopia suppressive gene EGR1 was upregulated by VL exposure. VL exposure induced significantly higher upregulation of EGR1 in chick chorioretinal tissues than blue light under the same conditions. Next, we conducted clinical research retrospectively to compare the AL elongation among myopic children who wore eyeglasses (VL blocked) and two types of contact lenses (partially VL blocked and VL transmitting). The data showed the VL transmitting contact lenses suppressed myopia progression most. These results suggest that VL is one of the important outdoor environmental factors for myopia control. Since VL is apt to be excluded from our modern society due to the excessive UV protection, VL exposure can be a preventive strategy against myopia progression. Violet light (360–400 nm wavelengths) suppressed the axial length elongation both in a chick myopia model and in human. The myopia suppressive gene EGR1 was upregulated by the violet light exposure. Violet light, one of the myopia suppressive factors in the outdoor environment, is deficient from our modern society.
Short-sightedness (myopia) has been increasing worldwide especially over the past 50 years. Our studies on chicks and humans revealed that violet light (360–400 nm wavelength) suppressed myopia progression. At a molecular level we found that violet light increased the expression of the gene EGR1 known to prevent myopia. Interestingly, violet light is deficient in our modern society because various ultraviolet-protected products are not transmitting violet light, and light sources such as LED irradiate no violet light. Ultraviolet protection is important for ocular health, but excessive ultraviolet protection, including violet light, should be reconsidered from the aspect of myopia control.
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326
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Patterns in longitudinal growth of refraction in Southern Chinese children: cluster and principal component analysis. Sci Rep 2016; 6:37636. [PMID: 27874105 PMCID: PMC5118713 DOI: 10.1038/srep37636] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 10/14/2016] [Indexed: 11/28/2022] Open
Abstract
In the present study we attempt to use hypothesis-independent analysis in investigating the patterns in refraction growth in Chinese children, and to explore the possible risk factors affecting the different components of progression, as defined by Principal Component Analysis (PCA). A total of 637 first-born twins in Guangzhou Twin Eye Study with 6-year annual visits (baseline age 7–15 years) were available in the analysis. Cluster 1 to 3 were classified after a partitioning clustering, representing stable, slow and fast progressing groups of refraction respectively. Baseline age and refraction, paternal refraction, maternal refraction and proportion of two myopic parents showed significant differences across the three groups. Three major components of progression were extracted using PCA: “Average refraction”, “Acceleration” and the combination of “Myopia stabilization” and “Late onset of refraction progress”. In regression models, younger children with more severe myopia were associated with larger “Acceleration”. The risk factors of “Acceleration” included change of height and weight, near work, and parental myopia, while female gender, change of height and weight were associated with “Stabilization”, and increased outdoor time was related to “Late onset of refraction progress”. We therefore concluded that genetic and environmental risk factors have different impacts on patterns of refraction progression.
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328
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Kwon JW, Choi JA, La TY. Serum 25-hydroxyvitamin D level is associated with myopia in the Korea national health and nutrition examination survey. Medicine (Baltimore) 2016; 95:e5012. [PMID: 27861336 PMCID: PMC5120893 DOI: 10.1097/md.0000000000005012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The aim of this article was to assess the associations of serum 25-hydroxyvitamin D [25(OH)D] and daily sun exposure time with myopia in Korean adults.This study is based on the Korea National Health and Nutrition Examination Survey (KNHANES) of Korean adults in 2010-2012; multiple logistic regression analyses were performed to examine the associations of serum 25(OH)D levels and daily sun exposure time with myopia, defined as spherical equivalent ≤-0.5D, after adjustment for age, sex, household income, body mass index (BMI), exercise, intraocular pressure (IOP), and education level. Also, multiple linear regression analyses were performed to examine the relationship between serum 25(OH)D levels with spherical equivalent after adjustment for daily sun exposure time in addition to the confounding factors above.Between the nonmyopic and myopic groups, spherical equivalent, age, IOP, BMI, waist circumference, education level, household income, and area of residence differed significantly (all P < 0.05). Compared with subjects with daily sun exposure time <2 hour, subjects with sun exposure time ≥2 to <5 hour, and those with sun exposure time ≥5 hour had significantly less myopia (P < 0.001). In addition, compared with subjects were categorized into quartiles of serum 25(OH)D, the higher quartiles had gradually lower prevalences of myopia after adjustment for confounding factors (P < 0.001). In multiple linear regression analyses, spherical equivalent was significantly associated with serum 25(OH)D concentration after adjustment for confounding factors (P = 0.002).Low serum 25(OH)D levels and shorter daily sun exposure time may be independently associated with a high prevalence of myopia in Korean adults. These data suggest a direct role for vitamin D in the development of myopia.
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329
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Holden BA, Jong M, Davis S, Wilson D, Fricke T, Resnikoff S. Nearly 1 billion myopes at risk of myopia-related sight-threatening conditions by 2050 - time to act now. Clin Exp Optom 2016; 98:491-3. [PMID: 26769175 DOI: 10.1111/cxo.12339] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Brien A Holden
- Brien Holden Vision Institute, University of New South Wales, Kensington, New South Wales, Australia
| | - Monica Jong
- Brien Holden Vision Institute, University of New South Wales, Kensington, New South Wales, Australia.
| | - Stephen Davis
- Brien Holden Vision Institute, University of New South Wales, Kensington, New South Wales, Australia
| | - David Wilson
- Brien Holden Vision Institute, University of New South Wales, Kensington, New South Wales, Australia
| | - Tim Fricke
- Brien Holden Vision Institute, University of New South Wales, Kensington, New South Wales, Australia
| | - Serge Resnikoff
- Brien Holden Vision Institute, University of New South Wales, Kensington, New South Wales, Australia
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Timucin OB, Arabaci M, Cuce F, Karatas B, Onalan S, Yasar M, Yildirim S, Karadag MF. The effects of light sources with different spectral structures on ocular axial length in rainbow trout (Oncorhynchus mykiss). Exp Eye Res 2016; 151:212-21. [DOI: 10.1016/j.exer.2016.08.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 08/18/2016] [Accepted: 08/29/2016] [Indexed: 11/28/2022]
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Ayaki M, Torii H, Tsubota K, Negishi K. Decreased sleep quality in high myopia children. Sci Rep 2016; 6:33902. [PMID: 27650408 PMCID: PMC5030671 DOI: 10.1038/srep33902] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 09/05/2016] [Indexed: 12/23/2022] Open
Abstract
The aim of the present study was to evaluate sleep quality in myopic children and adults. This cross sectional study surveyed 486 participants aged from 10 to 59 years with refractive errors using a questionnaire containing the Pittsburgh Sleep Quality Index (PSQI) and Hospital Anxiety and Depression Scale (HADS). Children (< 20 years) in the high myopia group exhibited the poorest PSQI scores (P < 0.01), while the adults showed no such correlations. Subscales of PSQI and HADS in children disclosed that the high myopia groups had the shortest sleep duration (P < 0.01), worst subjective sleep scores (P < 0.001), and latest bedtime (P < 0.05). Regression analyses in children significantly correlated myopic errors with PSQI (P < 0.05), sleep duration (P < 0.01), and bedtime (P < 0.01). Sleep efficacy (P < 0.05) and daytime dysfunction (P < 0.05) were significantly better in contact-lens users compared to the respective non-user groups across all participants. In conclusion, sleep quality in children was significantly correlated with myopic error, with the high myopia group worst affected.
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Affiliation(s)
- Masahiko Ayaki
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Hidemasa Torii
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Kazuo Tsubota
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Kazuno Negishi
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
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Abstract
Slowing the progression of myopia has become a considerable concern for parents of myopic children. At the same time, clinical science is rapidly advancing the knowledge about methods to slow myopia progression. This article reviews the peer-reviewed literature regarding several modalities attempting to control myopia progression. Several strategies have been shown to be ineffective for myopia control, including undercorrection of myopic refractive error, alignment fit gas-permeable contact lenses, outdoor time, and bifocal of multifocal spectacles. However, a recent randomized clinical trial fitted progressing myopic children with executive bifocals for 3 years and found a 39% slowing of myopia progression for bifocal-only spectacles and 50% treatment effect for bifocal spectacles with base-in prism, although there was not a significant difference in progression between the bifocal-only and bifocal plus prism groups. Interestingly, outdoor time has shown to be effective for reducing the onset of myopia but not for slowing the progression of myopic refractive error. More effective methods of myopia control include orthokeratology, soft bifocal contact lenses, and antimuscarinic agents. Orthokeratology and soft bifocal contact lenses are both thought to provide myopic blur to the retina, which acts as a putative cue to slow myopic eye growth. Each of these myopia control methods provides, on average, slightly less than 50% slowing of myopia progression. All studies have shown clinically meaningful slowing of myopia progression, including several randomized clinical trials. The most investigated antimuscarinic agents include pirenzepine and atropine. Pirenzepine slows myopia progression by approximately 40%, but it is not commercially available in the United States. Atropine provides the best myopia control, but the cycloplegic and mydriatic side effects render it a rarely prescribed myopia control agent in the United States. However, low-concentration atropine has been shown to provide effective myopia control with far fewer side effects than 1.0% atropine. Finally, two agents, low-concentration atropine and outdoor time have been shown to reduce the likelihood of myopia onset. Over the past few years, much has been learned about how to slow the progression of nearsightedness in children, but we still have a lot to learn.
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Wu X, Gao G, Jin J, Hua W, Tao L, Xu S, Tao F. Housing type and myopia: the mediating role of parental myopia. BMC Ophthalmol 2016; 16:151. [PMID: 27580859 PMCID: PMC5006500 DOI: 10.1186/s12886-016-0324-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 08/16/2016] [Indexed: 11/15/2022] Open
Abstract
Background Myopia has become a significant global public health concern, and is highly prevalent worldwide especially in Asian countries. It is associated with genetic factors as well as socioeconomic status; however, the underlying cause for school myopia has not been established. This study evaluates the impact of living environment on school myopia in Chinese school-aged children. Methods A large cross-sectional sample of area- and ethnicity-matched school children; a total of 43, 771 children from 12 cities participated in this study. The presence of myopia was self-reported and potential risk factors were determined by questionnaires. Results The self-reported prevalence of myopia in Chinese children was 31.8 % (n = 13, 928). In multiple logistic regression analysis, higer risk of myopia among school-aged children was significantly positively associated with both parental myopia (OR = 3.57; 95 % CI: 3.26–3.90), living in 1–3 floor (OR = 1.28; 95 % CI: 2.57–3.15), 4–6 floor (OR = 1.84; 95 % CI: 1.73–1.95) and 7 floor or more (OR = 2.02; 95 % CI: 1.88–2.16). Particularly, housing type was independently associated with myopia after stratified by parental myopia. An increasing prevalence of myopia was found with increasing floor of housing type in each outdoor time group. Conclusions Housing type was independently associated with myopia, after stratified by parental myopia. Flat room, lower living floor and more outdoor time may be protective factors for myopia among school-aged children in mainland China. Electronic supplementary material The online version of this article (doi:10.1186/s12886-016-0324-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xiaoyan Wu
- Department of Maternal, Child & Adolescent Health, School of Public Health, Anhui Medical University, 81 Meishan Road, Shushan District, Hefei, Anhui Province, 230032, China
| | - Guopeng Gao
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, 230032, China
| | - Juxiang Jin
- Department of Maternal, Child & Adolescent Health, School of Public Health, Anhui Medical University, 81 Meishan Road, Shushan District, Hefei, Anhui Province, 230032, China
| | - Wenjuan Hua
- Department of Maternal, Child & Adolescent Health, School of Public Health, Anhui Medical University, 81 Meishan Road, Shushan District, Hefei, Anhui Province, 230032, China
| | - Liming Tao
- Department of Ophthalmology, the Second Affiliated Hospital of Anhui Medical University, Hefei, 230601, China
| | - Shaojun Xu
- Department of Maternal, Child & Adolescent Health, School of Public Health, Anhui Medical University, 81 Meishan Road, Shushan District, Hefei, Anhui Province, 230032, China
| | - Fangbiao Tao
- Department of Maternal, Child & Adolescent Health, School of Public Health, Anhui Medical University, 81 Meishan Road, Shushan District, Hefei, Anhui Province, 230032, China.
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337
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Lagrèze WA, Joachimsen L, Schaeffel F. [Current recommendations for deceleration of myopia progression]. Ophthalmologe 2016; 114:24-29. [PMID: 27566176 DOI: 10.1007/s00347-016-0346-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Epidemiologic data demonstrate a rise in myopia prevalence. Therefore interventions to reduce the risk of myopia and its progression are needed and increasingly often asked for. METHODS Systematic literature search via PubMed in MEDLINE. RESULTS Myopia progression can be reduced by the following means which are listed according to their efficacy: (1) Atropine eye drops low dosed to avoid clinically relevant side effects, (2) optical means aiming at the correction of peripheral hyperopic defocus, e. g., multifocal contact lenses, and (3) increased daylight exposure. CONCLUSION Daylight exposure reduces the risk of incident myopia. Children should be advised to spend sufficient time outdoors, especially before and in primary school. Myopia progression can be effectively attenuated by low-dose topical atropine and multifocal contact lenses.
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Affiliation(s)
- W A Lagrèze
- Klinik für Augenheilkunde, Killianstr. 5, 79106, Freiburg, Deutschland.
| | - L Joachimsen
- Klinik für Augenheilkunde, Killianstr. 5, 79106, Freiburg, Deutschland
| | - F Schaeffel
- Forschungsinstitut für Augenheilkunde, Universität Tübingen, Tübingen, Deutschland
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338
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The influence of near work on myopic refractive change in urban students in Beijing: a three-year follow-up report. Graefes Arch Clin Exp Ophthalmol 2016; 254:2247-2255. [PMID: 27460281 DOI: 10.1007/s00417-016-3440-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 07/01/2016] [Accepted: 07/07/2016] [Indexed: 10/21/2022] Open
Abstract
PURPOSE To investigate the influence of daily activities on myopic refractive change and myopic onset in Chinese urban students. METHODS The Beijing Myopia Progression Study was a 3-year cohort study. Cycloplegic refraction and a daily activity questionnaire were assessed at baseline and at follow-up examinations. Refractive change was defined as the difference in cycloplegic spherical equivalent (SE) between the final follow-up and baseline. 386 students were initially enrolled in the baseline study. RESULTS At the final follow-up, 222 students (57.5 %) with completed refractive error and daily activity data were analyzed. These students spent 0.32 ± 2.33 h/day more on near work (p = 0.04), and 0.21 ± 1.31 h/day less on outdoor leisure (p = 0.02), than they did at baseline. In the multivariate analysis, the younger among the secondary students (β = 0.06, p < 0.001), and those with more near work hours at baseline (β = -0.028, p = 0.033), exhibited more myopic refractive change. However, myopic refractive change was not found to be significantly associated with near work hours in the primary students, or with time spent outdoors, in either school level. After stratifying the activity hours into quartile groups, students with a greater near work load at baseline (trend P = 0.03) exhibited a greater myopic refractive change and had a higher risk to develop myopia (hazard ratio, 95 % confidence interval: 5.19, 1.49-18.13), after adjusting for the confounders. However, no significant association was found related to outdoor activity. CONCLUSIONS In this cohort, children with a greater near work load at baseline exhibited more myopic refractive change and were also more likely to develop myopia. The protective effect of outdoor activity on myopic refractive change was not observed.
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Abstract
The recent "boom of myopia," described predominantly for East Asia, is assumed to result from increasingly demanding education programs that include extensive near work (and perhaps also extensive use of computers) and little exposure to bright light as found outdoors. Already in 1892, Hermann Cohn stated that the prevalence of myopia is related to the educational level which is related to the economic status of a country. It is not much appreciated that the rates of myopia were already high among school children in central Europe in the middle of the 19th century, as described by Hermann Cohn. From extensive research in recent times, three major approaches have emerged to interfere with myopia progression in children: (1) promoting exposure to bright light and enforce outdoor activity, (2) adapting/improving optical corrections and visual behavior to generate inhibitory signals for eye growth in the retina, and (3) applying atropine eye drops at low doses. However, Hermann Cohn had already proposed that low luminances during school work promote myopia development and requested that lighting in the classrooms needs to be at least "10 meter candles" (equivalent to an illuminance of 10 lux). Different from today, he explained the link between low light and myopia by shorter reading distances that he observed at low luminances of the reading surface (<<1 cd/m). He suggested that short reading distances should be avoided in children and described several devices to control them. He further suggested that reading duration should be limited and urged myopes to choose professions that do not involve extensive near work. He also studied the effects of atropine against myopia but concluded that the side effects make it less useful than simply "3-4 weeks without reading." In summary, a number of his findings were re-discovered today, but they are now much better supported by data, and their interpretations have changed, at least in some aspects.
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340
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Kang MT, Li SM, Peng X, Li L, Ran A, Meng B, Sun Y, Liu LR, Li H, Millodot M, Wang N. Chinese Eye Exercises and Myopia Development in School Age Children: A Nested Case-control Study. Sci Rep 2016; 6:28531. [PMID: 27329615 PMCID: PMC4916489 DOI: 10.1038/srep28531] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 06/06/2016] [Indexed: 11/09/2022] Open
Abstract
Chinese eye exercises have been implemented in China as an intervention for controlling children’s myopia for over 50 years. This nested case-control study investigated Chinese eye exercises and their association with myopia development in junior middle school children. Outcome measures were the onset and progression of myopia over a two-year period. Cases were defined as 1. Myopia onset (cycloplegic spherical equivalent ≤ −0.5 diopter in non-myopic children). 2. Myopia progression (myopia shift of ≥1.0 diopter in those who were myopic at baseline). Two independent investigators assessed the quality of Chinese eye exercises performance at the end of the follow-up period. Of 260 children at baseline (mean age was 12.7 ± 0.5 years), 201 were eligible for this study. There was no association between eye exercises and the risk of myopia-onset (OR = 0.73, 95%CI: 0.24–2.21), nor myopia progression (OR = 0.79, 95%CI: 0.41–1.53). The group who performed high quality exercises had a slightly lower myopia progression of 0.15 D than the children who did not perform the exercise over a period of 2 years. However, the limited sample size, low dosage and performance quality of Chinese eye exercises in children did not result in statistical significance and require further studies.
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Affiliation(s)
- Meng-Tian Kang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China
| | - Shi-Ming Li
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China
| | - Xiaoxia Peng
- Department of Epidemiology and Biostatistics, School of Public Health and Family Medicine, Capital Medical University, Beijing, China
| | - Lei Li
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China
| | - Anran Ran
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China
| | - Bo Meng
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China
| | - Yunyun Sun
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China
| | - Luo-Ru Liu
- Anyang Eye Hospital, Henan Province, China
| | - He Li
- Anyang Eye Hospital, Henan Province, China
| | - Michel Millodot
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom
| | - Ningli Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China
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341
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Miraldi Utz V. Nature versus nurture: A systematic approach to elucidate gene–environment interactions in the development of myopic refractive errors. Ophthalmic Genet 2016; 38:117-121. [DOI: 10.1080/13816810.2016.1183216] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Virginia Miraldi Utz
- Abrahamson Pediatric Eye Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
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342
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Education-Related Parameters in High Myopia: Adults versus School Children. PLoS One 2016; 11:e0154554. [PMID: 27152764 PMCID: PMC4859491 DOI: 10.1371/journal.pone.0154554] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Accepted: 03/28/2016] [Indexed: 01/29/2023] Open
Abstract
Purpose Since high myopia in the younger generation may differ etiologically from high myopia in older generations, we examined whether education-related parameters differ between high myopia in today´s school children and high pathological myopia in today´s elderly generation. Methods The investigation included the adult populations of the population-based Beijing Eye Study (BES) (3468 adults;mean age:64.6±9.8years;range:50–93years) and Central India Eye and Medical Study (CIEMS) (4711 adults;age:49.±13.2years;range:30–100years), and the children and teenager populations of the Shandong Children Eye Study (SCES) (6026 children;age:9.7±3.3years;range:4–18years;cycloplegic refractometry), Gobi Desert Children Eye Study (1565;age:11.9±3.5years;range:6–21 years;cycloplegic refractometry), Beijing Pediatric Eye Study (681 children;age:7.7±1.6years;range:5–13 years;non-cycloplegic refractometry,calculation of axial length to corneal curvature radius ratio), Beijing Children Eye Study (15066 children;age:13.2±3.4years;range:7–18years;non-cycloplegic refractometry), Beijing High School Teenager Eye Study (4677 children;age:16.9±0.7years;range:16–18years;non-cycloplegic refractometry). Results In the BES and CIEMS, educational level did not differ significantly between, or was significantly lower in the highly myopic group (myopic refractive error ≥6 diopters) than in the non-highly myopic group. In all non-adult study populations, higher prevalence of high myopia was significantly associated with higher degree of education related parameters such as attendance of high-level schools, and more time spent for indoors near work versus time spent outdoors. Conclusions Comparing associations of old or genetic high myopia in adults with new or acquired high myopia in school children revealed that education-related parameters did not show a clear association with old or genetic high myopia, while in contrast, new high myopia showed strong associations with education. It confirms previous studies that the two forms of high myopia not only differed in age of onset, but also in associations with education as well. The data support the notion of two types of high myopia. Future studies may assess whether the risk of pathologic myopic maculopathy and high myopia associated open-angle glaucoma differs between both types of high myopia.
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343
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Jee D, Morgan IG, Kim EC. Inverse relationship between sleep duration and myopia. Acta Ophthalmol 2016; 94:e204-10. [PMID: 26031352 DOI: 10.1111/aos.12776] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 04/28/2015] [Indexed: 01/13/2023]
Abstract
PURPOSES To investigate the association between sleep duration and myopia. METHODS This population-based, cross-sectional study using a nationwide, systemic, stratified, multistage, clustered sampling method included a total of 3625 subjects aged 12-19 years who participated in the Korean National Health and Nutrition Examination Survey 2008-2012. All participants underwent ophthalmic examination and a standardized interview including average sleep duration (hr/day), education, physical activity and economic status (annual household income). Refractive error was measured by autorefraction without cycloplegia. Myopia and high myopia were defined as ≤-0.50 dioptres (D) and ≤-6.0 D, respectively. Sleep durations were classified into 5 categories: <5, 6, 7, 8 and >9 hr. RESULTS The overall prevalence of myopia and high myopia were 77.8% and 9.4%, respectively, and the overall sleep duration was 7.1 hr/day. The refractive error increased by 0.10 D per 1 hr increase in sleep after adjusting for potential confounders including sex, age, height, education level, economic status and physical activity. The adjusted odds ratio (OR) for refractive error was 0.90 (95% confidence interval [CI], 0.83-0.97) per 1 hr increase in sleep. The adjusted OR for myopia was decreased in those with >9 hr of sleep (OR, 0.59; 95% CI, 0.38-0.93; p for trend = 0.006) than in those with <5 hr of sleep. However, high myopia was not associated with sleep duration. CONCLUSIONS This study provides the population-based, epidemiologic evidence for an inverse relationship between sleep duration and myopia in a representative population of Korean adolescents.
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Affiliation(s)
- Donghyun Jee
- Department of Ophthalmology and Visual Science; College of Medicine; Catholic University of Korea; Suwon Korea
- Department of Epidemiology and Biostatistics; Harvard School of Public Health; Boston MA USA
| | - Ian G. Morgan
- Research School of Biology; ARC Centre of Excellence in Vision Science; St. Vincent's Hospital; Australian National University; Canberra ACT Australia
| | - Eun chul Kim
- Department of Ophthalmology and Visual Science; College of Medicine; St. Mary's Hospital; Catholic University of Korea; Buchon Korea
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344
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Lan W, Yang Z, Feldkaemper M, Schaeffel F. Changes in dopamine and ZENK during suppression of myopia in chicks by intense illuminance. Exp Eye Res 2016; 145:118-124. [DOI: 10.1016/j.exer.2015.11.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 11/20/2015] [Accepted: 11/25/2015] [Indexed: 11/25/2022]
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345
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Hua WJ, Jin JX, Wu XY, Yang JW, Jiang X, Gao GP, Tao FB. Elevated light levels in schools have a protective effect on myopia. Ophthalmic Physiol Opt 2016; 35:252-62. [PMID: 25913873 DOI: 10.1111/opo.12207] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 03/02/2015] [Indexed: 02/05/2023]
Abstract
PURPOSE To determine whether elevated light levels in classrooms in rural areas can protect school-age children from myopia onset or myopia progression. METHODS A total of 317 subjects from 1713 eligible students aged six to 14 in four schools located in northeast China participated in the study. Students received a comprehensive eye examination including cycloplegic refraction and ocular biometry, which included axial length (AL), anterior chamber depth (ACD), and corneal curvature (CC) measurement, and completed a questionnaire. The intervention arm included 178 students in two schools with rebuilt elevated lighting systems and the control arm included 139 students in which lighting systems were unchanged. Results for the two arms were compared with a Wilcoxon rank sum test, a chi-squared test or a t-test, as appropriate. Factors that might help explain any differences were explored with multivariate linear regression analysis. RESULTS The median average illuminance of blackboards and desks and uniformity of desk lighting were significantly improved, however, the uniformity of blackboard lighting declined after intervention. At baseline, the mean refraction, AL, CC, ACD and myopia prevalence between the two arms were not significantly different. After 1 year, compared with the control arm the intervention arm had a lower incidence of new myopia onset (4% vs 10%; p = 0.029), a smaller decrease in refractive error among no myopic subjects (-0.25 dioptre [D] vs -0.47 D; p = 0.001), and shorter axial growth for both non-myopic (0.13 vs 0.18 mm; p = 0.023) and myopic subjects (0.20 vs 0.27 mm; p = 0.0001). Multivariate linear regression analysis showed the intervention program, lower hyperopic baseline refraction, lower father's education level, longer time sleeping and less time in screen-viewing activities were associated with less refractive shift in the direction of myopia in non-myopic children. For myopic subjects, myopia progression was significantly associated with family income only. The intervention program and older age had a protective effect on axial growth for both myopic and non-myopic subjects. The father's education level and sleep duration were significantly associated with axial growth in non-myopic children. CONCLUSIONS Elevated light levels in classrooms have a significant effect on myopia onset, decreases in refraction, and axial growth; if the findings of lighting intervention are reproduced in future studies, the ambient light levels in schools should be improved.
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Affiliation(s)
- Wen-Juan Hua
- School of Public Health, Anhui Medical University, Hefei, China
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346
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Tideman JWL, Polling JR, Voortman T, Jaddoe VWV, Uitterlinden AG, Hofman A, Vingerling JR, Franco OH, Klaver CCW. Low serum vitamin D is associated with axial length and risk of myopia in young children. Eur J Epidemiol 2016; 31:491-9. [PMID: 26955828 PMCID: PMC4901111 DOI: 10.1007/s10654-016-0128-8] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 02/08/2016] [Indexed: 01/08/2023]
Abstract
The aim of the study was to investigate the relationship between serum 25(OH)D levels and axial length (AL) and myopia in 6-year-old children. A total of 2666 children aged 6 years participating in the birth-cohort study Generation R underwent a stepwise eye examination. First, presenting visual acuity (VA) and AL were performed. Second, automated cycloplegic refraction was measured if LogMAR VA > 0.1. Serum 25-hydroxyvitamin D [25(OH)D] was determined from blood using liquid chromatography/tandem mass spectrometry. Vitamin D related SNPs were determined with a SNP array; outdoor exposure was assessed by questionnaire. The relationships between 25(OH)D and AL or myopia were investigated using linear and logistic regression analysis. Average 25(OH)D concentration was 68.8 nmol/L (SD ± 27.5; range 4–211); average AL 22.35 mm (SD ± 0.7; range 19.2–25.3); and prevalence of myopia 2.3 % (n = 62). After adjustment for covariates, 25(OH)D concentration (per 25 nmol/L) was inversely associated with AL (β −0.043; P < 0.01), and after additional adjusting for time spent outdoors (β −0.038; P < 0.01). Associations were not different between European and non-European children (β −0.037 and β −0.039 respectively). Risk of myopia (per 25 nmol/L) was OR 0.65 (95 % CI 0.46–0.92). None of the 25(OH)D related SNPs showed an association with AL or myopia. Lower 25(OH)D concentration in serum was associated with longer AL and a higher risk of myopia in these young children. This effect appeared independent of outdoor exposure and may suggest a more direct role for 25(OH)D in myopia pathogenesis.
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Affiliation(s)
- J Willem L Tideman
- Department of Ophthalmology, Erasmus Medical Center, NA2808, PO Box 5201, 3008 AE, Rotterdam, The Netherlands.,Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Jan Roelof Polling
- Department of Ophthalmology, Erasmus Medical Center, NA2808, PO Box 5201, 3008 AE, Rotterdam, The Netherlands.,Department of Orthoptics and Optometry, Faculty of Health, University of Applied Sciences, Utrecht, The Netherlands
| | - Trudy Voortman
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Vincent W V Jaddoe
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands.,Department of Paediatrics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - André G Uitterlinden
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands.,Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Albert Hofman
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Johannes R Vingerling
- Department of Ophthalmology, Erasmus Medical Center, NA2808, PO Box 5201, 3008 AE, Rotterdam, The Netherlands
| | - Oscar H Franco
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Caroline C W Klaver
- Department of Ophthalmology, Erasmus Medical Center, NA2808, PO Box 5201, 3008 AE, Rotterdam, The Netherlands. .,Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands.
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Galvis V, López-Jaramillo P, Tello A, Castellanos-Castellanos YA, Camacho PA, Cohen DD, Gómez-Arbeláez D, Merayo-Lloves J. Is myopia another clinical manifestation of insulin resistance? Med Hypotheses 2016; 90:32-40. [PMID: 27063082 DOI: 10.1016/j.mehy.2016.02.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 02/08/2016] [Indexed: 12/28/2022]
Abstract
Myopia is a multifactorial visual refraction disease, in which the light rays from distant objects are focused in front of retina, causing blurry vision. Myopic eyes are characterized by an increased corneal curvature and/or ocular axial length. The prevalence of myopia has increased in recent decades, a trend that cannot be attributed exclusively to genetic factors. Low and middle income countries have a higher burden of refractive error, which we propose could be a consequence of a shorter exposure time to a westernized lifestyle, a phenomenon that may also explain the rapid increase in cardiometabolic diseases, such as diabetes, among those populations. We suggest that interactions between genetic, epigenetic and a rapidly changing environment are also involved in myopia onset and progression. Furthermore, we discuss several possible mechanisms by which insulin resistance may promote abnormal ocular growth and myopia to support the hypothesis that insulin resistance and hyperinsulinemia are involved in its pathogenesis, providing a link between trends in myopia and those of cardiometabolic diseases. There is evidence that insulin have direct ocular growth promoting effects as well an indirect effect via the induction of insulin-like growth factors leading to decreases insulin-like growth factor-binding protein, also implicated in ocular growth.
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Affiliation(s)
- Virgilio Galvis
- Centro Oftalmológico Virgilio Galvis, Floridablanca, Santander, Colombia; Fundación Oftalmológica de Santander - FOSCAL, Floridablanca, Santander, Colombia
| | - Patricio López-Jaramillo
- Fundación Oftalmológica de Santander - FOSCAL, Floridablanca, Santander, Colombia; Instituto MASIRA, Facultad de Ciencias de la Salud, Universidad de Santander (UDES), Bucaramanga, Santander, Colombia.
| | - Alejandro Tello
- Centro Oftalmológico Virgilio Galvis, Floridablanca, Santander, Colombia; Departamento de Cirugía, Escuela de Medicina, Facultad de Ciencias de la Salud, Universidad Autónoma de Bucaramanga (UNAB), Bucaramanga, Santander, Colombia
| | | | - Paul Anthony Camacho
- Fundación Oftalmológica de Santander - FOSCAL, Floridablanca, Santander, Colombia
| | - Daniel Dylan Cohen
- Fundación Oftalmológica de Santander - FOSCAL, Floridablanca, Santander, Colombia; Instituto MASIRA, Facultad de Ciencias de la Salud, Universidad de Santander (UDES), Bucaramanga, Santander, Colombia
| | - Diego Gómez-Arbeláez
- Fundación Oftalmológica de Santander - FOSCAL, Floridablanca, Santander, Colombia
| | - Jesús Merayo-Lloves
- Instituto Universitario Fernández-Vega, Fundación de Investigación Oftalmológica, Universidad de Oviedo, Spain
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348
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Global trends in myopia management attitudes and strategies in clinical practice. Cont Lens Anterior Eye 2016; 39:106-16. [PMID: 26895778 DOI: 10.1016/j.clae.2016.02.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 02/03/2016] [Accepted: 02/03/2016] [Indexed: 12/14/2022]
Abstract
PURPOSE Myopia is a global public health issue; however, no information exists as to how potential myopia retardation strategies are being adopted globally. METHODS A self-administrated, internet-based questionnaire was distributed in six languages, through professional bodies to eye care practitioners globally. The questions examined: awareness of increasing myopia prevalence, perceived efficacy and adoption of available strategies, and reasons for not adopting specific strategies. RESULTS Of the 971 respondents, concern was higher (median 9/10) in Asia than in any other continent (7/10, p<0.001) and they considered themselves more active in implementing myopia control strategies (8/10) than Australasia and Europe (7/10), with North (4/10) and South America (5/10) being least proactive (p<0.001). Orthokeratology was perceived to be the most effective method of myopia control, followed by increased time outdoors and pharmaceutical approaches, with under-correction and single vision spectacles felt to be the least effective (p<0.05). Although significant intra-regional differences existed, overall most practitioners 67.5 (±37.8)% prescribed single vision spectacles or contact lenses as the primary mode of correction for myopic patients. The main justifications for their reluctance to prescribe alternatives to single vision refractive corrections were increased cost (35.6%), inadequate information (33.3%) and the unpredictability of outcomes (28.2%). CONCLUSIONS Regardless of practitioners' awareness of the efficacy of myopia control techniques, the vast majority still prescribe single vision interventions to young myopes. In view of the increasing prevalence of myopia and existing evidence for interventions to slow myopia progression, clear guidelines for myopia management need to be established.
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349
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French AN. Increasing children's time spent outdoors reduces the incidence of myopia. ACTA ACUST UNITED AC 2016; 21:76. [DOI: 10.1136/ebmed-2015-110321] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Cho SY. Prevention of myopia progression. JOURNAL OF THE KOREAN MEDICAL ASSOCIATION 2016. [DOI: 10.5124/jkma.2016.59.1.39] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Affiliation(s)
- Soon Young Cho
- Department of Ophthalmology, Dongguk University College of Medicine, Gyeongju, Korea
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