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Aim: To quantify the impact of prematurity on chromatic discrimination throughout childhood, from 2 to 15 years of age. Methods: We recruited two cohorts of children, as part of the TrackAI Project, an international project with seven different study sites: a control group of full‐term children with normal visual development and a group of children born prematurely. All children underwent a complete ophthalmological exam and an assessment of colour discrimination along the three colour axes: deutan, protan and trytan using a DIVE device with eye tracking technology. Results: We enrolled a total of 1872 children (928 females and 944 males) with a mean age of 6.64 years. Out of them, 374 were children born prematurely and 1498 were full‐term controls. Using data from all the children born at term, reference normative curves were plotted for colour discrimination in every colour axis. Pre‐term children presented worse colour discrimination than full‐term in the three colour axes (p < 0.001). Even after removing from the comparison, all pre‐term children with any visual disorder colour discrimination outcomes remained significantly worse than those from full‐term children. Conclusion: While colour perception develops throughout the first years of life, children born pre‐term face an increased risk for colour vision deficiencies. [ABSTRACT FROM AUTHOR]

Amblyopia is a reversible neurodevelopmental disorder but can cause vision loss if untreated, especially within critical period of visual neuroplasticity. We review different treatment modalities for amblyopia including refractive correction, occlusion therapy, medication, surgery, perceptual learning, and the more advanced binocular therapy. Binocular therapy can improve both visual acuity and stereoacuity, but whether it is superior to occlusion therapy remains controversial. Future studies to determine the optimal treatment duration, timing of initiation, dosage, and when to stepup treatment when other treatments become refractory are warranted. [ABSTRACT FROM AUTHOR]

Background The impacts of social restrictions for COVID-19 on children's vision and lifestyle remain unknown. Aims To investigate myopia incidence, spherical equivalent refraction (SER) and lifestyle changes among schoolchildren during the COVID-19 pandemic. Methods Two separate longitudinal cohorts of children aged 6-8 years in Hong Kong were included. The COVID-19 cohort was recruited at the beginning of the COVID-19 outbreak, whereas the pre-COVID-19 cohort was recruited before the COVID-19 pandemic. All children received ocular examinations, and answered a standardised questionnaire relating to their lifestyle, including time spent on outdoor activities and near work, both at baseline and at follow-up visits. Results A total of 1793 subjects were recruited, of whom 709 children comprised the COVID-19 cohort with 7.89±2.30 months of follow-up, and 1084 children comprised the pre-COVID-19 cohort with 37.54±3.12 months of follow-up. The overall incidence was 19.44% in the COVID-19 cohort, and 36.57% in pre-COVID-19 cohort. During the COVID-19 pandemic, the change in SER and axial length was -0.50±0.51 D and 0.29±0.35 mm, respectively; the time spent on outdoor activities decreased from 1.27±1.12 to 0.41±0.90 hours/day (p<0.001), while screen time increased from 2.45±2.32 to 6.89±4.42 hours/day (p<0.001). Conclusions We showed a potential increase in myopia incidence, significant decrease in outdoor time and increase in screen time among schoolchildren in Hong Kong during the COVID-19 pandemic. Our results serve to warn eye care professionals, and also policy makers, educators and parents, that collective efforts are needed to prevent childhood myopia--a potential public health crisis as a result of COVID-19. [ABSTRACT FROM AUTHOR]

Aims To determine the prevalence and predictors of myopic macular degeneration (MMD) in a consortium of Asian studies. Methods Individual-level data from 19 885 participants from four population-based studies, and 1379 highly myopic participants (defined as axial length (AL) >26.0 mm) from three clinic-based/school-based studies of the Asian Eye Epidemiology Consortium were pooled. MMD was graded from fundus photographs following the meta-analysis for pathologic myopia classification and defined as the presence of diffuse choroidal atrophy, patchy chorioretinal atrophy, macular atrophy, with or without 'plus' lesion (lacquer crack, choroidal neovascularisation or Fuchs' spot). Area under the curve (AUC) evaluation for predictors was performed for the population-based studies. Results The prevalence of MMD was 0.4%, 0.5%, 1.5% and 5.2% among Asians in rural India, Beijing, Russia and Singapore, respectively. In the population-based studies, older age (per year; OR=1.13), female (OR=2.0), spherical equivalent (SE; per negative diopter; OR=1.7), longer AL (per mm; OR=3.1) and lower education (OR=1.9) were associated with MMD after multivariable adjustment (all p<0.001). Similarly, in the clinic-based/school-based studies, older age (OR=1.07; p<0.001), female (OR=2.1; p<0.001), longer AL (OR=2.1; p<0.001) and lower education (OR=1.7; p=0.005) were associated with MMD after multivariable adjustment. SE had the highest AUC of 0.92, followed by AL (AUC=0.87). The combination of SE, age, education and gender had a marginally higher AUC (0.94). Conclusion In this pooled analysis of multiple Asian studies, older age, female, lower education, greater myopia severity and longer AL were risk factors of MMD, and myopic SE was the strongest single predictor of MMD. [ABSTRACT FROM AUTHOR]

Objective To investigate the associations of singlenucleotide polymorphisms (SNPs) in the ZC3H11B, ZFHX1B, VIPR2, SNTB1 and MIPEP genes with severities of myopia in Chinese populations. Methods Based on previous myopia genome-wide association studies, five SNPs (ZC3H11B rs4373767, ZFHX1B rs13382811, VIPR2 rs2730260, SNTB1 rs7839488 and MIPEP rs9318086) were selected for genotyping in a Chinese cohort of 2079 subjects: 252 extreme myopia, 277 high myopia, 393 moderate myopia, 366 mild myopia and 791 non-myopic controls. Genotyping was performed by TaqMan assays. Allelic frequencies of the SNPs were compared with myopia severities and ophthalmic biometric measurements. Results The risk allele T of ZC3H11B SNP rs4373767 was significantly associated with high myopia (OR=1.39, p=0.007) and extreme myopia (OR=1.34, p=0.013) when compared with controls, whereas ZFHX1B rs13382811 (allele T, OR=1.33, p=0.018) and SNTB1 rs7839488 (allele G, OR=1.71, p=8.44E- 05) were significantly associated with extreme myopia only. In contrast, there was no significant association of these SNPs with moderate or mild myopia. When compared with mild myopia, subjects carrying T allele of rs4373767 had a risk of progressing to high myopia (spherical equivalent =-6 dioptres) (OR=1.29, p=0.017). Similarly, the T allele of rs13382811 also imposed a significant risk to high myopia (OR=1.36, p=0.007). In quantitative traits analysis, SNPs rs4373767, rs13382811 and rs7839488 were correlated with axial length and refractive errors. Conclusions We confirmed ZC3H11B as a susceptibility gene for high and extreme myopia, and ZFHX1B and SNTB for extreme myopia in Chinese populations. Instead of myopia onset, these three genes were more likely to impose risks of progressing to high and extreme myopia. [ABSTRACT FROM AUTHOR]

Aim To determine the association between dementia and age-related macular degeneration (AMD) using meta-analysis. Methods We searched in the MEDLINE, EMBASE, Web of Knowledge, PsycInfo and Cochrane database of systematic reviews for studies published from March 1959 to March 2018. We included cross-sectional, case--control and cohort studies that evaluated the association of dementia/Alzheimer's disease (AD) with AMD (as outcome) and the association of AMD with dementia/AD (as outcome). Studies that compared cognitive functions between AMD and controls were also included. The summary outcomes, namely odds ratio (OR), relative risk, mean differences and corresponding 95% CIs, were estimated using random effects models. We performed sensitivity analysis based on study quality and individual study effect to control for potential biases. results Among 2159 citation records, we identified 21 studies consisting of 7 876 499 study subjects for meta-analysis. Patients with dementia (padjusted≤0.017, OR≥1.24, I²≤9%) or AD (p=0.001, ORunadjusted=2.22, I2=50%) were at risk for AMD, particularly for late AMD (padjusted<0.001, OR=1.37, I²=0). AMD was also significantly associated with increased risk of AD/ cognitive impairment (padjusted=0.037, OR=2.42, I2=38%). Moreover, patients with AMD had poorer cognitive functions when compared with controls, including Mini-Mental State Examination (p<0.001, I²≤79%) and Trail Making Test A (p<0.001, I²=0). Sensitivity analysis and Egger's test indicated our results were less likely biased. Conclusions A significant association between dementia/AD and AMD calls for greater clinical awareness. The cost-effectiveness of routine screening for the other condition in patients with primary diagnosis of dementia/AD or AMD requires further study. [ABSTRACT FROM AUTHOR]

Objective To investigate the associations between 16 single-nucleotide polymorphisms (SNPs) in 14 genetic loci and keratoconus in an independent Chinese cohort. Methods This cross-sectional, case-control association study included a Chinese cohort of 133 patients with keratoconus and 371 control subjects. In a recent meta-analysis study, we identified association of 16 SNPs in 14 gene loci with keratoconus. In this study, we genotyped these 16 SNPs in all the patients and controls and analysed their association with keratoconus, its clinical severities and progression profiles. We also analysed the genotype-phenotype correlation between individual SNPs and steep keratometry, flat keratometry (Kf), average keratometry (Avg K) and best-fit sphere diameter (BFS) of the anterior and posterior corneal surface. Results Among the 16 selected SNPs, rs1324183 in the MPDZ-NF1B locus showed a significant association with keratoconus (OR=2.22; 95% CI 1.42 to 3.45, p=4.30×10-4), especially severe keratoconus (OR=5.10, 95% CI 1.63 to 15.93, p=0.005). The rs1324183 A allele was positively associated with anterior Kf (p=0.008), anterior Avg K (p=0.017), posterior Kf (p=0.01) and negatively associated with apex pachymetry (p=0.007) and anterior BFS (p=0.023) in keratoconus. The other 15 SNPs had no significant association with keratoconus or genotype-phenotype correlations. Conclusions This study confirmed the association of SNP rs1324183 in MPDZ-NF1B with keratoconus and revealed the association of this SNP with keratoconus severity and corneal parameters. It is thus a putative genetic marker for monitoring the progression of keratoconus to a severe form and facilitating early intervention. [ABSTRACT FROM AUTHOR]

Background Retinopathy of prematurity (ROP) is one of the leading causes of childhood blindness. Use of antenatal steroid can reduce neonatal morbidity and mortality in preterm births, but its effect on ROP remained controversial. We aim to determine the association between antenatal steroid and risk of ROP by a systematic review and meta-analysis. Methods Reported studies on the association between antenatal steroid and risk of ROP or severe ROP were identified from MEDLINE and Embase databases from their inception to November 2016. Outcome measures were ORs with 95% CIs. Extracted data were pooled using a random-effect model or fixed-effect model where appropriate. Heterogeneity was assessed, and sensitivity analysis was performed. Results A total of 434 relevant studies were identified, and 28 studies were eligible for the meta-analysis, involving 20 731 neonates with 4202 cases of ROP. Among the 28 studies included, 13 studies provided data evaluating the association between antenatal steroid use and severe ROP, involving 4999 neonates with 792 cases of severe ROP. Antenatal steroid administration was associated with a reduced risk of ROP development (ORunadjusted = 0.82, 95% CI 0.68 to 0.98; ORadjusted = 0.67, 95% CI 0.47 to 0.94) and progression to severe ROP (ORunadjusted = 0.58, 95% CI 0.40 to 0.86). Conclusion Antenatal steroid administration is associated with a reduced risk of ROP development and progression to severe ROP. Our results strengthened the indications of antenatal steroid therapy to high-risk mothers giving preterm births, especially in low-income and middle-income countries where antenatal steroid are not yet widely used. [ABSTRACT FROM AUTHOR]

Aims To investigate the association of the paired box gene 6 (PAX6) with different severities of myopia. Methods A total of four haplotype-tagging singlenucleotide polymorphisms (SNPs; rs2071754, rs3026354, rs3026390 and rs628224) and two previously reported SNPs (rs644242 and rs662702) in the PAX6 gene were analysed in a Hong Kong Chinese cohort of 1288 myopia subjects (including 252 extreme myopia, 277 high myopia, 393 moderate myopia and 366 mild myopia) and 791 no myopia controls. Allelic association analyses were performed for individual SNPs in different subgroups of myopia and in combined myopia, followed by a meta-analysis of our current data with reported data on PAX6 in myopia. results The association of tagging SNPs rs2071754 and rs644242 with extreme myopia could not withstand multiple correction (rs2071754: OR=1.25, P value=0.031; rs644242: OR=1.33, P value=0.032). In the meta-analysis, rs644242 showed an enhanced, significant association with extreme myopia (OR=1.27, 95% CI 1.10 to 1.46, P value=0.001; I2=0%). In contrast, there was no significant association between the PAX6SNPs and high, moderate or mild myopia. No linear correlation was found between the PAX6SNPs and axial length. Conclusion This study provides additional evidence suggesting that the PAX6 SNP rs644242 is associated with extreme myopia but not lower grade myopia. Thus, PAX6 may be implicated in the development or progression into severe myopia. Further longitudinal studies are warranted. [ABSTRACT FROM AUTHOR]