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 ...

PURPOSE.To investigate the posttreatment neuronal rescue effects of Lycium barbarum polysaccharides (LBP) in an acute ocular hypertensive (AOH) model. METHODS.Intraocular pressure (IOP) was elevated manometrically to 80 mm Hg (AOH) or 15 mm Hg (sham) for 120 minutes in adult Sprague-Dawley rats. Five experimental groups were considered: Three AOH groups were pretreated with PBS (vehicle) (n ¼ 9), LBP 1 mg/kg (n ¼ 8), or 10 mg/kg (n ¼ 13), and one AOH group was posttreated with LBP 10 mg/kg (n ¼ 8), once daily. The sham cannulation group (n ¼ 5) received no treatment. Pretreatments commenced 7 days before and posttreatment 6 hours after AOH, and continued up through postcannulation day 28. All the animals underwent optical coherence tomography and electroretinogram measurements at baseline and postcannulation days 10 and 28. The ganglion cell layer (GCL) densities were quantified at day 28. RESULTS.Both inner retinal layer thickness (IRLT) and positive scotopic threshold response (pSTR) underwent significant reduction ( ‡50% of thickness and amplitude) in the vehicle group (P < 0.05). Pretreatment with LBP 1 and 10 mg/kg retained 77 6 11% and 89 6 8% of baseline IRLT, respectively, and preserved pSTR functions. The posttreatment group showed a significant reduction in IRLT (À35 6 8%, P < 0.001) and pSTR (~48% of baseline, P < 0.001) on day 10. By day 28, there was an improvement in functional pSTR (~72% of baseline, P > 0.05) with no significant further thinning (À40 6 8%, P ¼ 0.15) relative to day 10. GCL density was reduced in vehicle control (P ¼ 0.0001), but did not differ between sham and pre-and posttreated AOH groups.CONCLUSIONS. The rescue effect of LBP posttreatment was observed later, which arrested the secondary degeneration and improved the retinal function.

Purpose To investigate the effect of simultaneous dual‐focus (DF) on retinal activities measured by global flash multifocal electroretinogram (mfERG). Methods Thirty adults were recruited for mfERG measurement under three conditions: in‐focus (i.e., no defocus), +2.50 D DF and +7.50 D DF, administered using single vision contact lenses and DF lenses. The direct component (DC) and the induced component (IC) of the mfERG were pooled into central macular (0–8°), para‐macular (8–18°) and peri‐macular (18–30°) regions, and then compared across the three conditions using two‐way, repeated measures ANOVA. Results Simultaneous DF had a significant effect on the IC amplitude, which was significantly stronger under +7.50 D DF (p < 0.01) than for the in‐focus condition, which was mostly derived from the central and para‐macular regions. No significant effect was observed for the +2.50 D DF condition. Conclusion Under the effect of relatively strong simultaneous DF integration, the retina showed an enhanced retinal response, which originated from the inner retina. Compared with the peri‐macular region, central and para‐macular responses appeared to be enhanced.

Introduction Vision is critical for children’s development. However, prevalence of visual impairment (VI) is high in students with special educational needs (SEN). Other than VI, SEN students are prone to having functional deficits. Whether visual problems relate to these functional deficits is unclear. This study aimed to assess the impact of vision on visual processing functions and balance in SEN students through a community service. Methods Visual acuity (VA) and contrast sensitivity were measured in a total of 104 (aged 14.3±4.3) SEN students as the visual outcomes, followed by retinoscopy. Visual processing function assessment included facial expression recognition by card matching examiner’s facial expression matching, and visual orientation recognition. Dynamic balance, by Timed Up and Go test, and static standing balance (postural sway in double-legged standing with feet-together and tandem-stance for open-eye and closed-eye conditions) were assessed. Static balance was presented in terms of the maximal medial-lateral and antero-posterior sways. Results Of the 104 students, 62 (59.6%) were classified as visually impaired according to WHO classification of visual impairment based on presenting distance acuity. Ocular problems (e.g. optic nerve anomaly, uncorrected/ under-corrected refractive errors) and neurological anomalies were the major causes of vision loss. VA was positively associated with visual processing functions (all p ≤ 0.01), as SEN students with better vision tended to perform better in visual orientation and facial expression recognition tasks, as well as dynamic balance function (p = 0.04). For the static balance, postural sway and VA showed a positive relationship under open-eye and tandem stance conditions. However, the relationship between postural sway and VA became negative under closed-eye and tandem stance conditions. Conclusion This study found a high prevalence of SEN students with visual impairment, in which many of them were undetected. Optometric examination is important to improve their visual function to minimize the effect of vision on functional performance. Vision is critical in visual processing as well as playing an important role in maintaining balance in SEN students.