Purpose: People in Hong Kong generally live in a densely populated area and their homes are smaller compared with most other cities worldwide. Interestingly, East Asian cities with high population densities seem to have higher myopia prevalence, but the association between them has not been established. This study investigated whether the crowded habitat in Hong Kong is associated with refractive error among children. Methods: In total, 1075 subjects [Mean age (S.D.): 9.95 years (0.97), 586 boys] were recruited. Information such as demographics, living environment, parental education and ocular status were collected using parental questionnaires. The ocular axial length and refractive status of all subjects were measured by qualified personnel.

Key Points Question Is an optical defocus treatment associated with slowed myopia progression among schoolchildren experiencing lockdown related to the COVID-19 pandemic? Findings In this exploratory analysis of 2 cohort studies including 171 schoolchildren during COVID-19 lockdown, treatment using a defocus incorporated multiple segments lens was associated with 46% less myopia progression and 34% less axial elongation compared with regular single vision lens treatment. Meaning These findings suggest that an optical defocus treatment may be associated with slower myopia progression, which has been exaggerated during the COVID-19 pandemic, among schoolchildren.

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Purpose To quantify the defocus characteristics in the near‐work environment at home and investigate the relationship with subsequent myopia progression. Methods Fifty subjects (aged 7–12 years) were recruited and followed for 1 year. The home near‐work environment (writing desk) was measured at a baseline home‐visit using the Kinect‐for‐Windows to capture a 3‐dimensional image. The depth values of the image were then converted into scene defocus with respect to the subject’s viewpoint. The defocus characteristics were quantified as the dioptric volume (the total amount of net defocus, or DV) and standard deviation of the defocus values (SD D ). Information on home size, time spent outdoors, and in front of a desk were also obtained. Univariate correlation, and multivariate regression were used to assess the association between myopia progression, defocus characteristics, and other co‐variates. Results The baseline spherical equivalent refraction ( M ) and refraction change over 1 year (∆ M ) were − 1.51 ± 2.02 D and − 0.56 ± 0.45 D respectively. DV was not significantly correlated with ∆ M (Spearman’s ρ = −0.25, p = 0.08), while SD D was negatively correlated to ∆ M (Spearman’s ρ = −0.42, p = 0.003). Although SD D was not a significant predictor in multivariate analysis, the regional DV at 15°–20° eccentricity was significant ( p = 0.001). Home size ( F 2,50 = 7.01, p = 0.002) and time spent outdoors (Independent t = −2.13, p = 0.04) were also associated with ∆ M , but not time spent in front of desk (Independent t = 0.78, p = 0.44). Conclusion The defocus profile in the home environment within the para‐central field of view is associated with childhood refractive error development.

Citation: Li SZ-C, Yu W-Y, Choi K-Y, et al. Subclinical decrease in central inner retinal activity is associated with myopia development in children. Invest Ophthalmol Vis Sci. 2017;58:4399-4406. DOI:10.1167/ iovs.16-21279 PURPOSE. To investigate the characteristics of retinal electrophysiological activity in relation to early myopia development in children.METHODS. Fifty-six children aged 6 to 9 years with emmetropic refractive error (defined as ‡ À0.5 diopter [D] and þ0.5 D) were recruited. Cycloplegic refraction, axial length, and global flash multifocal electroretinogram (MOFO mfERG) at 49% and 96% contrast levels were recorded in all children at their first visit. The refraction and axial length measurements were repeated after 1 year. The amplitudes and implicit times of the direct component (DC) and the induced component (IC) of the MOFO mfERG obtained at the initial visit were analyzed. Correlations between the MOFO mfERG parameters and changes in refractive error and axial length were investigated. RESULTS.The mean spherical equivalent refractive error and axial length of the eyes of the children at the first visit were þ0.19 6 0.33 D and 23.14 6 0.6 mm, respectively. After 1 year, the mean refractive error increased by À0.55 6 0.53 D, whereas axial length increased by 0.37 6 0.22 mm. The changes in refractive error and axial length were significantly correlated with the central IC amplitudes at 49% contrast level measured at the initial visit (q ¼ 0.46, P < 0.001 and q ¼ À0.34, P ¼ 0.01, respectively).CONCLUSIONS. The prospective changes we have shown are believed to derive from central inner retina. These changes appear to precede myopia and could be a potential reference for juvenile myopia development.Keywords: myopia development, multifocal electroretinogram, children vision, inner retina E xcessive eyeball elongation causes myopia. In severe cases, it may result in retinal stretching, thinning, and changes in retinal cell morphology and pathology. Application of the ERG technique has provided ample evidence to confirm that myopia results in impaired retinal function. It has been reported that myopia in adults was associated with decreased nonlinear components of ERG responses, 1 multifocal ERG (mfERG) responses, 2,3 retinal adaptation response, 4 and inner retinal function. [5][6][7] Axial length was shown to be linearly related to ERG amplitudes, 8 first-order kernel, and the first slice of second-order kernel of mfERG responses. 9 The reduction in mfERG responses in myopic adults is believed to be due to the deterioration in retinal function associated with long-standing myopia. However, this explanation cannot be applied to myopic children, and discrepancies of ERG characteristics have been noted between myopic adults and children.2,7 Luu and his colleagues 2 conducted a cross-sectional study of mfERG measurement in 104 children and 31 adults with a range of refractive errors. They found a significant correlation between refractive error and mfERG response in adults, but this correlation ...