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Background In adult patients with high myopia (HM), progressive axial elongation poses a significant risk for the development of subsequent ocular complications that may lead to visual impairment. Effective strategies to reduce or prevent further axial elongation in highly myopic adult patients have not been available so far. Recent studies suggested that medically lowering intraocular pressure (IOP) may reduce axial elongation.Objective This clinical randomised controlled trial (RCT) aims to evaluate the efficacy of medical IOP reduction in adult patients with progressive HM (PHM).Trial design Single-centre, open-label, prospective RCT.Methods This RCT will recruit 152 participants with PHM at the Zhongshan Ophthalmic Center (ZOC). Randomised in a ratio of 1:1, participants will receive IOP-lowering eyedrops (intervention group) or will be followed without treatment (control group) for 12 months. Follow-up visits will be conducted at 1, 6 and 12 months after baseline. Only one eye per eligible participant will be included for analysis. The primary outcome is the change in axial length (AL) within the study period of 12 months. Secondary outcomes include the incidence and progression of visual field (VF) defects, changes in optic disc morphology and incidence and progression of myopic maculopathy. Difference in AL changes between the two groups will be analysed using linear regression analysis. For the secondary outcomes, a multifactor Poisson regression within a generalised linear model will be used to estimate the relative risk of progression in VF defects and myopic maculopathy, and the rate of thinning in retinal nerve fibre layer and ganglion cell-inner plexiform will be assessed through Kaplan-Meier curves and log-rank tests.Ethics and dissemination Full ethics approval for this trial has been obtained from the Ethics Committee of ZOC, Sun Yat-sen University, China (ID: 2023KYPJ110). Results of this trial will be disseminated through peer-reviewed journals and conference presentations.Trial registration number NCT05850936.

Background Case-finding is a recommended approach for dementia early detection in the community.Aims To investigate the discriminant validity and cost-effectiveness of a stepwise dementia case-finding approach in a Singaporean older adult community.Methods The two-phase study was conducted in the community from 2009 to 2015 in Singapore. A total of 3780 participants (age ≥60 years) completed phase I (a brief cognitive screening); 918 completed phase II and were included in the final analysis. In phase I, all participants were administered the Abbreviated Mental Test (AMT) and the Progressive Forgetfulness Question (PFQ). Those who screened positive on either test were invited to phase II, whereby the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) and a formal neuropsychological battery were administered, followed by the research diagnosis of no cognitive impairment, cognitive impairment no dementia (CIND)-Mild (≤2 impaired cognitive domains), CIND-Moderate (>2 impaired domains) or dementia. Receiver operating characteristic curve analyses were conducted for the different cognitive instruments. All discriminant indices were calculated, including sensitivity, specificity, positive and negative predictive values (NPV) and accuracy. Cost-effectiveness analysis was conducted by estimating the amount of screening time needed and the number of older adults requiring re-evaluation in two case-finding scenarios, ie, with or without preselection by the PFQ.Results The stepwise case-finding approach (preselection by the PFQ, then MMSE or MoCA or AMT) showed an excellent NPV (>99%) and accuracy (>86%) for excluding dementia-free cases. Without preselection by the PFQ, screening time for the three cognitive tools were 317.5, 317.5 and 254 hours, with 159, 302 and 175 screen-positive older adults involved in further evaluation. By adopting the stepwise case-finding approach, total screening time were 156.5, 156.5 and 126.2 hours, which decreased by 50.7%, 50.7% and 50.3% as compared with those without preselection. Furthermore, after preselection, only 98, 167 and 145 screen-positive older adults required further evaluation, corresponding to a reduction of 38.4%, 44.7% and 17.1% in the numbers compared with those without preselection.Conclusions A stepwise approach for dementia case-finding should be implemented in the community to minimise the time and resources needed for large-scale early detection of dementia.

Introduction Diabetes mellitus is a growing public health epidemic in Asia. We examined the impact of type 2 diabetes, glycemic control and microvascular complications on mortality and cardiovascular outcomes in a multiethnic population-based cohort of Asians without prior cardiovascular disease.Research design and methods This was a prospective population-based cohort study in Singapore comprising participants from the three major Asian ethnic groups: Chinese, Malays and Indians, with baseline examination in 2004–2011. Participants with type 1 diabetes and those with cardiovascular disease at baseline were excluded. Type 2 diabetes, Hemoglobin A1c (HbA1c) levels and presence of microvascular complications (diabetic retinopathy and nephropathy) were defined at baseline. The primary outcome was all-cause mortality and major adverse cardiovascular events (MACEs), defined as a composite of cardiovascular mortality, myocardial infarction, stroke and revascularization, collected using a national registry.Results A total of 8541 subjects were included, of which 1890 had type 2 diabetes at baseline. Subjects were followed for a median of 6.4 (IQR 4.8–8.8) years. Diabetes was a significant predictor of mortality (adjusted HR 1.74, 95% CI 1.45 to 2.08, p

Objective To describe the rational for, and the methods that will be employed to develop, the WHO package of eye care interventions (PECI).Methods and analysis The development of the package will be conducted in four steps: (1) selection of eye conditions (for which interventions will be included in the package) based on epidemiological data on the causes of vision impairment and blindness, prevalence estimates of eye conditions and health facility data; (2) identification of interventions and related evidence for the selected eye conditions from clinical practice guidelines and high-quality systematic reviews by a technical working group; (3) expert agreement on the inclusion of eye care interventions in the package and the description of resources required for the provision of the selected interventions; and (4) peer review. The project will be led by the WHO Vision Programme in collaboration with Cochrane Eyes and Vision. A Technical Advisory Group, comprised of public health and clinical experts in the field, will provide technical input throughout all stages of development.Results After considering the feedback of Technical Advisory Group members and reviewing-related evidence, a final list of eye conditions for which interventions will be included in the package has been collated.Conclusion The PECI will support Ministries of Health in prioritising, planning, budgeting and integrating eye care interventions into health systems. It is anticipated that the PECI will be available for use in 2021.

Background Deep learning (DL) is promising to detect glaucoma. However, patients' privacy and data security are major concerns when pooling all data for model development. We developed a privacy-preserving DL model using the federated learning (FL) paradigm to detect glaucoma from optical coherence tomography (OCT) images. Methods This is a multicentre study. The FL paradigm consisted of a 'central server' and seven eye centres in Hong Kong, the USA and Singapore. Each centre first trained a model locally with its own OCT optic disc volumetric dataset and then uploaded its model parameters to the central server. The central server used FedProx algorithm to aggregate all centres' model parameters. Subsequently, the aggregated parameters are redistributed to each centre for its local model optimisation. We experimented with three three-dimensional (3D) networks to evaluate the stabilities of the FL paradigm. Lastly, we tested the FL model on two prospectively collected unseen datasets. Results We used 9326 volumetric OCT scans from 2785 subjects. The FL model performed consistently well with different networks in 7 centres (accuracies 78.3%-98.5%, 75.9%-97.0%, and 78.3%-97.5%, respectively) and stably in the 2 unseen datasets (accuracies 84.8%-87.7%, 81.3%-84.8%, and 86.0%-87.8%, respectively). The FL model achieved non-inferior performance in classifying glaucoma compared with the traditional model and significantly outperformed the individual models. Conclusion The 3D FL model could leverage all the datasets and achieve generalisable performance, without data exchange across centres. This study demonstrated an OCT-based FL paradigm for glaucoma identification with ensured patient privacy and data security, charting another course toward the real-world transition of artificial intelligence in ophthalmology. [ABSTRACT FROM AUTHOR]

Background/aims To identify ocular determinants of iridolenticular contact area (ILCA), a recently introduced swept-source optical coherence tomography (SSOCT) derived parameter, and assess the association between ILCA and angle closure. Methods In this population-based cross-sectional study, right eyes of 464 subjects underwent SSOCT (SS-1000, CASIA, Tomey Corporation, Nagoya, Japan) imaging in the dark. Eight out of 128 cross-sectional images (evenly spaced 22.5° apart) were selected for analysis. Matlab (Matworks, Massachusetts, USA) was used to measure ILCA, defined as the circumferential extent of contact area between the pigmented iris epithelium and anterior lens surface. Gonioscopic angle closure (GAC) was defined as non-visibility of the posterior trabecular meshwork in two or more angle quadrants. Results The mean age of subjects was 62±6.6 years, with the majority being female (65.5%). 143/464 subjects (28.6%) had GAC. In multivariable linear regression analysis, ILCA was significantly associated with anterior chamber width (β=1.03, p=0.003), pupillary diameter (β=-1.9, p<0.001) and iris curvature (β=-17.35, p<0.001). ILCA was smaller in eyes with GAC compared with those with open angles (4.28±1.6 mm² vs 6.02±2.71 mm², p<0.001). ILCA was independently associated with GAC (β=-0.03, p<0.001), iridotrabecular contact index (β=-6.82, p<0.001) or angle opening distance (β=0.02, p<0.001) after adjusting for covariates. The diagnostic performance of ILCA for detecting GAC was acceptable (AUC=0.69). Conclusions ILCA is a significant predictor of angle closure independent of other biometric factors and may reflect unique anatomical information associated with pupillary block. ILCA represents a novel biometric risk factor in eyes with angle closure. [ABSTRACT FROM AUTHOR]

Aims To evaluate the effectiveness of glaucoma screening using glaucoma suspect (GS) referral criteria assessed on colour fundus photographs in Singapore's Integrated Diabetic Retinopathy Programme (SiDRP). Methods A case-control study. This study included diabetic subjects who were referred from SiDRP with and without GS between January 2017 and December 2018 and reviewed at Singapore National Eye Centre. The GS referral criteria were based on the presence of a vertical cup-to-disc ratio (VCDR) of =0.65 and other GS features. The final glaucoma diagnosis confirmed from electronic medical records was retrospectively matched with GS status. The sensitivity, specificity and positive predictive value (PPV) of the test were evaluated. Results Of 5023 patients (2625 with GS and 2398 without GS) reviewed for glaucoma, 451 (9.0%, 95% CI 8.2% to 9.8%) were confirmed as glaucoma. The average follow-up time was 21.5±10.2 months. Using our current GS referral criteria, the sensitivity, specificity and PPV were 81.6% (95% CI 77.7% to 85.1%), 50.6% (95% CI 49.2% to 52.1%) and 14.0% (95% CI 13.4% to 14.7%), respectively, resulting in 2257 false positive cases. Increasing the VCDR cut-off for referral to =0.80, the specificity increased to 93.9% (95% CI 93.1% to 94.5%) but the sensitivity decreased to 11.3% (95% CI 8.5% to 14.6%), with a PPV of 15.4% (95% CI 12.0% to 19.4%). Conclusions Opportunistic screening for glaucoma in a lower VCDR group could result in a high number of unnecessary referrals. If healthcare infrastructures are limited, targeting case findings on a larger VCDR group with high specificity will still be beneficial. [ABSTRACT FROM AUTHOR]

Purpose (1) To determine the independent association of dry eye symptoms with health-related quality of life (HRQoL) in the Singapore population and (2) to further investigate which factors mediate this association. Methods In this cross-sectional study, 7707 participants were included. The presence of dry eye symptoms was defined as experiencing at least one out of the six symptoms either ’often’ or ’all the time’. The EuroQoL-5 dimensions (EQ-5D) utility instrument (raw scores converted to UK time trade-off (TTO) values) was used to assess generic HRQoL and the overall score from the Visual Functioning Questionnaire for visual functioning. The association between dry eye symptoms and EQ-5D was investigated using multivariable linear regression, adjusting for demographic and socioeconomic information, comorbidities, systemic and ocular examinations results. Mediation analysis was used to determine whether certain factors mediated this association. Results After adjusting for relevant factors, those with dry eye symptoms had significantly lower HRQoL (difference in EQ-5D TTO: −0.062 (95% CI −0.073 to –0.050)), with the inability to open eyes affected the most (−0.101 (95% CI −0.161 to –0.042)), followed by a sandy sensation (−0.089 (95% CI −0.121 to –0.058)), a burning sensation (−0.070 (95% CI −0.105 to –0.036)), red eyes (−0.059 (95% CI −0.082 to –0.036)), a dry sensation (−0.058 (95% CI −0.072 to –0.044)) and crusting of eyelids (−0.040 (95% CI −0.071 to –0.008)). Visual functioning and the presence of recent falls accounted for 8.63% (4.98%–14.5%) and 2.93% (0.04%–5.68%) of the indirect relationship between dry eye and HRQoL, respectively. Conclusion Dry eye symptoms were independently associated with poor HRQoL. Moreover, this was partly mediated by reduced visual functioning and experiencing recent falls. Our results suggest that efforts to reduce severity of dry eye symptoms are essential to optimise patients’ overall functioning and well-being. [ABSTRACT FROM AUTHOR]

Background Association between baseline visual impairment (VI) bilaterality and severity, and associated causes; and incident and frequent falls at 6 years in a multiethnic Asian population aged ≥60 years. Methods It is a population-based prospective cohort study. Visual acuity was clinically measured at both visits. Self-reported incidence and frequency of falls were defined as having no fall at baseline but having one fall and ≥2 incident falls in the 12 months prior to the follow-up visit, respectively. Results Of the 1972 older participants (mean age (SD): 67.37 (5.4) years), 253 (12.8%) and 69 (3.5%) reported at least one fall and ≥2 falls, respectively, at a 6-year follow-up. After multivariable adjustments, baseline bilateral VI, but not unilateral, was associated with higher odds of any incident falls (mild bilateral VI: OR=1.79, 95% CI 1.07 to 2.98; moderate-severe VI in one eye and mild VI in the other eye: OR=1.58, 95% CI 1.01 to 2.47). However, having any form of bilateral VI (OR ranging between 2.46 and 4.32; all p<0.05) and even unilateral mild VI (OR=2.34, 95% CI 1.09 to 5.03) significantly increased the odds of incident frequent falls, compared with bilateral normal vision. VI caused by correctable (OR=2.02, 95% CI 1.19 to 3.44) and uncorrectable (OR=3.09, 95% CI 1.08 to 8.80) eye conditions were both associated with greater odds of incident frequent falls, compared with no VI. Conclusions Baseline bilateral but not unilateral VI conferred nearly two-fold higher odds of incident fall. Importantly, even mild unilateral VI conferred a substantially greater likelihood of frequent falls from correctable and uncorrectable conditions. [ABSTRACT FROM AUTHOR]

Background Case-finding is a recommended approach for dementia early detection in the community. Aims To investigate the discriminant validity and cost-effectiveness of a stepwise dementia case-finding approach in a Singaporean older adult community. Methods The two-phase study was conducted in the community from 2009 to 2015 in Singapore. A total of 3780 participants (age =60 years) completed phase I (a brief cognitive screening); 918 completed phase II and were included in the final analysis. In phase I, all participants were administered the Abbreviated Mental Test (AMT) and the Progressive Forgetfulness Question (PFQ). Those who screened positive on either test were invited to phase II, whereby the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA) and a formal neuropsychological battery were administered, followed by the research diagnosis of no cognitive impairment, cognitive impairment no dementia (CIND)-Mild (=2 impaired cognitive domains), CIND-Moderate (>2 impaired domains) or dementia. Receiver operating characteristic curve analyses were conducted for the different cognitive instruments. All discriminant indices were calculated, including sensitivity, specificity, positive and negative predictive values (NPV) and accuracy. Cost-effectiveness analysis was conducted by estimating the amount of screening time needed and the number of older adults requiring re-evaluation in two case-finding scenarios, ie, with or without preselection by the PFQ. Results The stepwise case-finding approach (preselection by the PFQ, then MMSE or MoCA or AMT) showed an excellent NPV (>99%) and accuracy (>86%) for excluding dementia-free cases. Without preselection by the PFQ, screening time for the three cognitive tools were 317.5, 317.5 and 254 hours, with 159, 302 and 175 screen-positive older adults involved in further evaluation. By adopting the stepwise case-finding approach, total screening time were 156.5, 156.5 and 126.2 hours, which decreased by 50.7%, 50.7% and 50.3% as compared with those without preselection. Furthermore, after preselection, only 98, 167 and 145 screen-positive older adults required further evaluation, corresponding to a reduction of 38.4%, 44.7% and 17.1% in the numbers compared with those without preselection. Conclusions A stepwise approach for dementia case-finding should be implemented in the community to minimise the time and resources needed for large-scale early detection of dementia. [ABSTRACT FROM AUTHOR]

Purpose To investigate the predictive factors for myopic macular degeneration (MMD) and progression in adults with myopia. Methods We examined 828 Malay and Indian adults (1579 myopic eyes) with myopia (spherical equivalent (SE) ≤-0.5 dioptres) at baseline who participated in both baseline and 12-year follow-up visits of the Singapore Malay Eye Study and the Singapore Indian Eye Study. Eye examinations, including subjective refraction and axial length (AL) measurements, were performed. MMD was graded from fundus photographs following the Meta-Analysis for Pathologic Myopia classification. The predictive factors for MMD development and progression were assessed in adults without and with MMD at baseline, respectively as risk ratios (RR) using multivariable modified Poisson regression models. The receiver operating characteristic curve was used to visualise the performance of the predictive models for the development of MMD, with performance quantified by the area under the curve (AUC). Results The 12-year cumulative MMD incidence was 10.3% (95% CI 8.9% to 12.0%) among 1504 myopic eyes without MMD at baseline. Tessellated fundus was a major predictor of MMD (RR=2.50, p<0.001), among other factors including age, worse SE and longer AL (all p<0.001). The AUC for prediction of MMD development was found to be 0.78 (95% CI 0.76 to 0.80) for tessellated fundus and increased significantly to an AUC of 0.86 (95% CI 0.84 to 0.88) with the combination of tessellated fundus with age, race, gender and SE (p<0.001). Older age (p=0.02), worse SE (p<0.001) and longer AL (p<0.001) were found to be predictors of MMD progression. Conclusions In adults with myopia without MMD, tessellated fundus, age, SE and AL had good predictive value for incident MMD. In adults with MMD, 1 in 10 eyes experienced progression over the same period. Older age, more severe myopia and longer AL were independent risk factors for progression. [ABSTRACT FROM AUTHOR]

Aims To identify blood metabolite markers associated with intraocular pressure (IOP) in a population-based cross-sectional study. Methods This study was conducted in a multiethnic Asian population (Chinese, n=2805; Indians, n=3045; Malays, n=3041 aged 40-80 years) in Singapore. All subjects underwent standardised systemic and ocular examinations, and biosamples were collected. Selected metabolites (n=228) in either serum or plasma were analysed and quantified using nuclear magnetic resonance spectroscopy. Least absolute shrinkage and selection operator regression was used for metabolites selection. Multivariable linear regression was used to evaluate the relationship between metabolites and IOP in each of the three ethnic groups, followed by a metaanalysis combining the three cohorts. Results Six metabolites, including albumin, glucose, lactate, glutamine, ratio of saturated fatty acids to total fatty acids (SFAFA) and cholesterol esters in very large high-density lipoprotein (HDL), were significantly associated with IOP in all three cohorts. Higher levels of albumin (per SD, beta=0.24, p=0.002), lactate (per SD, beta=0.27, p=0.008), glucose (per SD, beta=0.11, p=0.010) and cholesterol esters in very large HDL (per SD, beta=0.47, p=0.006), along with lower levels of glutamine (per SD, beta=0.17, p<0.001) and SFAFA (per SD, beta=0.21, p=0.008) were associated with higher IOP levels. Conclusion We identify several novel blood metabolites associated with IOP. These findings may provide insight into the physiological and pathological processes underlying IOP control. [ABSTRACT FROM AUTHOR]

Aim To investigate the association between the extent of iridotrabecular contact and other quantitative anterior segment dimensions measured by swept-source optical coherence tomography (SS-OCT; CASIA SS-1000, Tomey, Nagoya, Japan) with intraocular pressure (IOP). Methods Cross-sectional study. All subjects who were ≥50 years with no history of glaucoma, ocular surgery or trauma, underwent SS-OCT imaging (eight equally spaced radial scans), Goldman applanation tonometry and gonioscopy on the same day. We measured iridotrabecular contact (ITC) index and area, total volume of trabeculo-iris space area and angle opening distance at 500 and 750 from the scleral spur (TISA 500 and 750, AOD 500 and 750, respectively), anterior chamber depth (ACD), volume, area and width, pupil diameter, lens vault and iris volume.Their relationship with IOP (dependent variable) was assessed by locally weighted scatterplot smoothing (Lowess) regression with change-point analysis and generalised additive models adjusted for confounders. Results 2027 right eyes of mostly Chinese Singaporeans (90%) were analysed. ITC index above a threshold of ~60% (95% CI 34% to 92%) was significantly associated with higher IOP. Independent of the extent of ITC, ACD was also significantly associated with higher IOP below a threshold of 2.5 mm (95% CI 2.33 mm to 2.71 mm). Greater ITC index and shallower ACD had a joint association with IOP. A model including ACD and ITC index was more predictive of IOP than a model considering these variables separately, particularly for women with gonioscopically closed angles (R2 52.7%, p<0.05). Conclusions The extent of angle closure and the ACD below a certain threshold had a significant joint association with IOP. These parameters, as biometrical surrogates of mechanical obstruction of the aqueous outflow, may jointly contribute to elevated IOP, particularly in women with gonioscopic angle closure. [ABSTRACT FROM AUTHOR]

Aims To report the 6-year incidence of optical coherence tomography (OCT)-derived age-related changes in drusen volume and related systemic and ocular associations. Methods Chinese adults aged 40 years and older were assessed at baseline and 6 years with colour fundus photography (CFP) and spectral domain (SD) OCT. CFPs were graded for age-related macular degeneration (AMD) features and drusen volume was generated using commercially available automated software. Results A total of 4172 eyes of 2580 participants (mean age 58.12±9.03 years; 51.12% women) had baseline and 6-year follow-up CFP for grading, of these, 2130 eyes of 1305 participants had gradable SD-OCT images, available for analysis. Based on CFP grading, 136 (3.39%) participants developed incident early AMD and 10 (0.25%) late AMD. Concurrently, retinal pigment epithelial-Bruch's membrane (RPE-BrC) volumes decreased, remained stable and increased in 6.8%, 78.5% and 14.7%, respectively, over 6 years. In eyes where RPE-BrC volumes were >0 mm3 at baseline, this was associated with two-fold higher prevalence rate of any AMD at baseline (p<0.001). Multivariable analysis showed that when compared with eyes where RPE-BrC volume was unchanged, volume decrease was significantly associated with older age (OR=1.30; p<0.001), smoking (OR=2.21; p=0.001) and chronic kidney disease (OR=3.4, p=0.008), while increase was associated with older age (OR=1.36; p<0.001) and hypertension (OR=1.43; p=0.016). Conclusion AMD incidence detected at 6 years on CFP and correlated OCT-derived drusen volume measurement change is low. Older age and some systemic risk factors are associated with drusen volume change, and our data provide new insights into relationship between systemic risk factors and outer retinal morphology in Asian eyes. [ABSTRACT FROM AUTHOR]

Aims To examine the relationship between vision impairment (VI) and employment outcomes in a multiethnic Asian population. Methods We included 7608 Asian individuals aged ≥40 years (mean (SD) age: 58.4 (10.3) years; 64.8% male) from the Singapore Epidemiology Eye Disease Study (response rate: 78.8%), a population-based cohort study (mean follow-up period: 6.2 years). Presenting visual acuity (VA) was assessed using a logarithm of the minimum angle of resolution (logMAR) chart, with VI defined as mild (VA >0.3 to <0.6 logMAR) and moderate to severe (VA ≥0.6 logMAR). Self-reported employment statuses at both baseline and follow-up were used as outcomes. Underemployment was defined as a decline in occupational skill level, categorised by International Standard Classification of Occupations, at follow-up compared with baseline. Multinomial logistic regression models were used to determine independent associations between VI and various employment outcomes, adjusted for variables that were found to significantly differ across employment statuses. Results Presenting VI was prevalent in 20.2% (N=1536) of participants. Compared with those without VI, participants with mild and moderate to severe VI were more likely to be unemployed at baseline (OR 1.47, 95% CI 1.15 to 1.87, p=0.002 and 2.74, 95% CI 1.94 to 3.89, p<0.001, respectively). At follow-up, participants with any VI at baseline were more likely to be underemployed (OR 1.46, 95% CI 1.03 to 2.05, p=0.033). Conclusion VI, even when mild, is associated with unemployment and underemployment. Future studies should investigate whether visual interventions could be used as part of a multipronged strategy to improve employment outcomes for the population. [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]

Purpose To evaluate the performance of swept source optical coherence tomography (SS-OCT) to detect gonioscopic angle closure using different classification algorithms. Methods This was a cross-sectional study of 2028 subjects without ophthalmic symptoms recruited from a community-based clinic. All subjects underwent gonioscopy and SS-OCT (Casia, Tomey Corporation, Nagoya, Japan) under dark room conditions. For each eye, 8 out of 128 frames (22.5° interval) were selected to measure anterior chamber parameters namely anterior chamber width, depth, area and volume (ACW, ACD, ACA, and ACV), lens vault (LV), iris curvature (IC), iris thickness (IT) from 750 µm and 2000 µm from the scleral spur, iris area and iris volume. Five diagnostic algorithms--stepwise logistic regression, random forest, multivariate adaptive regression splines, recursive partitioning and Naïve Bayes were evaluated for detection of gonioscopic angle closure (defined as =2 closed quadrants). The performance of the horizontal frame was compared with that of other meridians. Results Data from 1988 subjects, including 143 (7.2%) with gonioscopic angle closure, were available for analysis. They were divided into two groups: training (1391, 70%) and validation (597, 30%). The best algorithm for detecting gonioscopic angle closure was stepwise logistic regression with an area under the curve of 0.91 (95% CI 0.88 to 0.93) using all parameters, and 0.88 (95% CI 0.82 to 0.93) using only ACA, LV and IC of the horizontal meridian scan. Conclusions A stepwise logistic regression model incorporating SS-OCT measurements has a high diagnostic ability to detect gonioscopic angle closure. [ABSTRACT FROM AUTHOR]

Background/aims To evaluate the performances of deep learning (DL) algorithms for detection of presence and extent pterygium, based on colour anterior segment photographs (ASPs) taken from slit-lamp and hand-held cameras. Methods Referable pterygium was defined as having extension towards the cornea from the limbus of >2.50 mm or base width at the limbus of >5.00 mm. 2503 images from the Singapore Epidemiology of Eye Diseases (SEED) study were used as the development set. Algorithms were validated on an internal set from the SEED cohort (629 images (55.3% pterygium, 8.4% referable pterygium)), and tested on two external clinic-based sets (set 1 with 2610 images (2.8% pterygium, 0.7% referable pterygium, from slit-lamp ASP); and set 2 with 3701 images, 2.5% pterygium, 0.9% referable pterygium, from hand-held ASP). Results The algorithm's area under the receiver operating characteristic curve (AUROC) for detection of any pterygium was 99.5%(sensitivity=98.6%; specificity=99.0%) in internal test set, 99.1% (sensitivity=95.9%, specificity=98.5%) in external test set 1 and 99.7% (sensitivity=100.0%; specificity=88.3%) in external test set 2. For referable pterygium, the algorithm's AUROC was 98.5% (sensitivity=94.0%; specificity=95.3%) in internal test set, 99.7% (sensitivity=87.2%; specificity=99.4%) in external set 1 and 99.0% (sensitivity=94.3%; specificity=98.0%) in external set 2. Conclusion DL algorithms based on ASPs can detect presence of and referable-level pterygium with optimal sensitivity and specificity. These algorithms, particularly if used with a handheld camera, may potentially be used as a simple screening tool for detection of referable pterygium. Further validation in community setting is warranted. Synopsis/precis DL algorithms based on ASPs can detect presence of and referable-level pterygium optimally, and may be used as a simple screening tool for the detection of referable pterygium in community screenings. [ABSTRACT FROM AUTHOR]

Aims To characterise the association between visual field (VF) defects and myopic macular degeneration (MMD) in highly myopic adults without glaucoma. Methods Participants (n=106; 181 eyes) with high myopia (HM; spherical equivalent =-5.0 D or axial length (AL) =26 mm), after excluding glaucoma and glaucoma suspects, from the Singapore Epidemiology of Eye Diseases-HM study were included in this cross-sectional study. Humphrey VF (central 24-2 threshold), cup-disc ratio (CDR) and intraocular pressure (IOP) measurements were performed. Mean deviation (MD) and pattern SD (PSD), VF defects (normal or abnormal; p<0.05 in =3 non-edge contiguous locations) and pattern (eg, generalised sensitivity loss) were analysed. MMD presence was diagnosed from fundus photographs. Generalised estimating equations were used for analysing factors (MD, PSD, VF defects, CDR and IOP) associated with MMD. Results Mean age was 55.4±9.9 years and 51.9% were women (AL=26.7±1.1 mm). MMD eyes had lower MD (-3.8±2.9 dB vs -1.1±1.4 dB) and higher PSD (2.8±1.7 dB vs 1.7±0.6 dB). A higher percentage of MMD eyes (n=48) had abnormal VF (62.5% vs 28.6%; p<0.001) compared with no MMD (n=133 eyes). VF pattern in MMD eyes was significantly different from eyes without MMD (p=0.001) with greater generalised sensitivity loss (53.3% vs 10.5%) and arcuate defects (16.7% vs 10.5%). In multivariate analyses, MD (OR=1.52) and PSD (OR=1.67) were significantly (p=0.003) associated with MMD, but VF defects were not associated with MMD. Conclusion Highly myopic adults with MMD may have VF loss when compared with highly myopic patients without MMD even in adults without glaucoma. [ABSTRACT FROM AUTHOR]

Aim To provide contemporary longitudinal data on the incidence and progression of diabetic retinopathy (DR) in a multi-ethnic population of whites, African Americans, Chinese and Hispanics in the United States. Methods A prospective, multi-region, multi-ethnic population-based cohort study that included 498 participants with diabetes, aged 45-84 years at baseline, from the Multi-Ethnic Study of Atherosclerosis with retinal images obtained twice, on average 8 years apart. Presence and severity of DR were graded from these retinal images according to the modified Airlie House classification system. Main outcome measures were 8-year incidence, progression and improvement of DR, and their associated risk factors. Results Over the 8 years, the cumulative rates were 19.2% for incident DR, 17.3% for DR progression, 23.3% for DR improvement, 2.7% for incident vision-threatening DR, 1.8% for incident proliferative DR and 2.2% for incident macular oedema. In multivariate analysis, significant risk factors associated with incident DR were higher glycosylated haemoglobin (relativerisk (RR) 1.28; 95% CI: 1.16 to 1.41) and higher systolic blood pressure (RR 1.14; 95% CI: 1.04 to 1.25). Significant factors associated with DR progression were higher glycosylated haemoglobin (RR 1.20; 95% CI: 1.00 to 1.43) and higher low-density lipoprotein cholesterol (RR 1.01; 95% CI: 1.00 to 1.03). Conclusion Over an 8-year period, approximately one in five participants with diabetes developed DR, while almost a quarter of those with DR at baseline showed improvement, possibly reflecting the positive impact of clinical and public health efforts in improving diabetes care in the United States over the last two decades. [ABSTRACT FROM AUTHOR]

Background We examined the associations between the 6-year incidence of age-related macular degeneration (AMD) and vision-related quality of life (VRQoL), and the contribution of presenting visual acuity (VA), in an Asian population. Methods Fundus images from the Singapore Chinese Eye Study, a population-based cohort study (baseline: 2009-2011; follow-up: 2015-2017), were graded using a modified Wisconsin age-related maculopathy grading system. Incident AMD was defined as no baseline AMD in both eyes and early/late AMD in the worse eye at follow-up. Presenting VA was assessed using the logarithm of the minimum angle of resolution chart at 4 m under standard lighting conditions with habitual correction. Multiple linear regression models determined the associations between AMD incidence with changes in the Rasch-transformed scores of the Reading, Mobility and Emotional VRQoL domains of the 32-item Impact of Visual Impairment (IVI-32) questionnaire, adjusted for traditional confounders. The contribution of presenting VA to changes in VRQoL was also estimated. Results Of the 2251 participants without AMD at baseline (mean age (SD): 57.7 (9) years, 51.4% women), 101 (4.5%) and 11 (0.5%) developed incident early and late AMD at follow-up, respectively. Incident late AMD was associated with significant 30.3%, 32.5% and 30.9% decrements in Reading, Mobility and Emotional IVI scores, respectively. The contribution of presenting VA ranged between 1.62% and 4.35% of the observed decrements. No significant associations were noted with incident early AMD. Conclusion Incident late AMD had a substantial impact on all aspects of VRQoL, with presenting VA contributing only minimally to this longitudinal relationship. [ABSTRACT FROM AUTHOR]

Background/aims Obesity is a well-known risk factor for diabetes, but its association with diabetic retinopathy (DR) is inconclusive, in particular in Asians. We aimed to assess whether body mass index (BMI) is associated with the presence and severity of DR in Asian populations with diabetes. Methods Pooled analysis of individual-level cross-sectional data from 10 010 adults with diabetes who participated in 12 population-based studies conducted in China, India, Japan, Russia (Asian), Singapore and South Korea that were part of the Asian Eye Epidemiology Consortium (AEEC). BMI was calculated as weight in kilograms divided by height in square metres and categorised into normal (<25 kg/m², reference), overweight (25-29.9 kg/m²) and obese (≥30 kg/m²). Any-DR (n=1669) and vision-threatening DR (VTDR, n=489) were assessed from digital retinal photographs and graded according to standard protocols. Each study was analysed separately using multivariable logistic regression models adjusted for age, sex, haemoglobin A1c%, systolic blood pressure and diabetes duration, and the estimated odds ratios (ORs) and 95% confidence interval (CIs) from all studies were then combined using random-effects models. Results In multivariable models, obesity showed a significant inverse association with any-DR (pooled OR (95% CI) =0.74 (0.59 to 0.91)) and VTDR (0.75 (0.60 to 0.93)). Similarly, in continuous analysis, BMI showed a significant inverse association with both any-DR (0.93 (0.87 to 0.99)) and VTDR (0.79 (0.68 to 0.92) per SD increase). Overweight did not show a significant association with any-DR. Conclusions Among Asian adults with diabetes, both BMI and obesity showed an inverse association with DR. These findings warrant confirmation in further longitudinal studies. [ABSTRACT FROM AUTHOR]

Purpose To evaluate the effect of signal strength (SS) on optical coherence tomography (OCT) parameters, and devise an algorithm to adjust the effect, when acceptable SS cannot be obtained. Methods 5085 individuals (9582 eyes), aged =40 years from the Singapore Epidemiology of Eye Diseases population-based study were included. Everyone underwent a standardised ocular examination and imaging with Cirrus HD-OCT. Effect of SS was evaluated using multiple structural breaks linear mixed-effect models. Expected change for increment in SS between 4 and 10 for individual parameter was calculated. Subsequently we devised and evaluated an algorithm to adjust OCT parameters to higher SS. Results Average retinal nerve fibre layer (RNFL) thickness showed shift of 4.11 µm from SS of 5 to 6. Above 6, it increased by 1.72 and 3.35 µm to 7 and 8; and by 1.09 µm (per unit increase) above 8 SS. Average ganglion cell-inner plexiform layer (GCIPL) thickness shifted 5.15 µm from SS of 5 to 6. Above 6, increased by 0.94 µm from 7 to 8; and by 0.16 µm (per unit increase) above 8 SS. When compared with reference in an independent test set, the algorithm produced less systemic bias. Algorithm-adjusted average RNFL was 0.549 µm thinner than the reference, while the unadjusted one was 2.841 µm thinner (p<0.001). Algorithm-adjusted and unadjusted average GCIPL was 1.102 µm and 2.228 µm thinner (p<0.001). Conclusions OCT parameters can be adjusted for poor SS using an algorithm. This can potentially assist in diagnosis and monitoring of glaucoma when scans with acceptable SS cannot be acquired from patients in clinics. [ABSTRACT FROM AUTHOR]

Purpose We described the 6-year incidence and changes of retinopathy, and their associated risk factors in a multi-ethnic Asian population without diabetes. Methods We included 4374 participants with non-diabetes from a population-based cohort, the Singapore Epidemiology of Eye Disease Study, with gradable retinal photographs at baseline and 6-year follow-up visit. Retinopathy was assessed according to the modified Airlie House classification system. Results Over the 6-year period, the cumulative rates were 2.5% (106/4279) for retinopathy incidence, 1.0% (1/95) for retinopathy progression and 68.4% (65/95) for retinopathy regression. In multivariable analysis, higher diastolic blood pressure (DBP) (risk ratio (RR)=1.02; 95% CI: 1.00 to 1.04; per 10 mm Hg increase in DBP) and wider retinal arteriolar calibre (RR=1.36; 95% CI: 1.13 to 1.63; per SD increase in central retinal artery equivalent) were associated with higher risk of incident retinopathy, while higher level of high-density lipoprotein (HDL) was associated with lower risk of incident retinopathy (RR=0.56; 95% CI: 0.32 to 0.99; per mmol/L increase in HDL). Compared with Chinese, Malays were more likely to have retinopathy regression (RR=1.63; 95% CI: 1.20 to 2.22), while overweight (RR=0.47; 95% CI: 0.26 to 0.84) and higher glycosylated haemoglobin (HbA1c) level (RR=0.58; 95% CI: 0.37 to 0.93; per per cent increase in HbA1c) were associated with lower likelihood of retinopathy regression. Conclusion Risk of developing retinopathy in Asians without diabetes is generally low. However, regression of retinopathy over time is common, suggesting that these retinopathy signs may reflect subclinical reversible microvascular dysfunction. Several metabolic risk factors are associated with incidence or regression of retinopathy, suggesting that good metabolic control may still be important in the management of non-diabetic retinopathy. [ABSTRACT FROM AUTHOR]

Aims To compare the shape of the anterior surface of the peripapillary sclera (PPS) between glaucoma and healthy subjects. Methods 88 primary open angle glaucoma (POAG), 98 primary angle closure glaucoma (PACG) and 372 age-matched and gender-matched healthy controls were recruited in this study. The optic nerve head of one randomly selected eye of each subject was imaged with spectral domain optical coherence tomography. The shape of the PPS was measured through an angle defined between a line parallel to the nasal anterior PPS boundary and one parallel to the temporal side. A negative value indicated that the PPS followed an inverted v-shaped configuration (peak pointing towards the vitreous), whereas a positive value indicated that it followed a v-shaped configuration. Results The mean PPS angle in normal controls (4.56±5.99°) was significantly smaller than that in POAG (6.60±6.37°, p=0.011) and PACG (7.90±6.87°, p<0.001). The v-shaped PPS was significantly associated with older age (ß=1.79, p<0.001), poorer best-corrected visual acuity (ß=3.31, p=0.047), central corneal thickness (ß=-0.28, p=0.001), peripapillary choroidal thickness (ß=-0.21, p<0.001) and presence of POAG (ß=1.94, p<0.009) and PACG (ß=2.96, p<0.001). The v-shaped configuration of the PPS significantly increased by 1.46° (p=0.001) in healthy controls for every 10-year increase in age, but not in glaucoma groups. Conclusions The v-shaped configuration of the PPS was more pronounced in glaucoma eyes than in healthy eyes. This posterior bowing of the PPS may have an impact on the biomechanical environment of the optic nerve head. [ABSTRACT FROM AUTHOR]

COVID-19 has led to massive disruptions in societal, economic and healthcare systems globally. While COVID-19 has sparked a surge and expansion of new digital business models in different industries, healthcare has been slower to adapt to digital solutions. The majority of ophthalmology clinical practices are still operating through a traditional model of 'brick-and-mortar' facilities and 'face-to-face' patient-physician interaction. In the current climate of COVID-19, there is a need to fuel implementation of digital health models for ophthalmology. In this article, we highlight the current limitations in traditional clinical models as we confront COVID-19, review the current lack of digital initiatives in ophthalmology sphere despite the presence of COVID-19, propose new digital models of care for ophthalmology and discuss potential barriers that need to be considered for sustainable transformation to take place. [ABSTRACT FROM AUTHOR]

Aims To evaluate the normative profiles for neuroretinal rim area (RA) in a multiethnic Asian population. Methods Subjects were recruited from the Singapore Epidemiology of Eye Diseases (2009-2015) study and underwent standardised examinations. RA measurements were performed using Cirrus high-definition optical coherence tomography (Carl Zeiss Meditec). Multivariable linear regression with generalised estimating equation model was used to evaluate the associations between demographic, systemic and ocular factors with RA. Results A total of 9394 eyes from 5116 subjects (1724 Chinese, 1463 Malay, 1929 Indian) were included in the final analysis. The mean (±SD) of RA was 1.28 (±0.23) mm² for Chinese, 1.33 (±0.26) mm² for Malays, and 1.23 (±0.23) mm² for Indians. The 5th percentile value for RA was 0.94 mm² for Chinese, 0.96 mm² for Malay, and 0.89 mm² for Indian. In multivariable analysis, following adjustment for age, gender, body mass index, diabetes mellitus, hyperlipidaemia, history of cataract surgery, axial length, intraocular pressure (IOP) and disc area, Indian eyes have smaller RA when compared with Malays (β=-0.074; 95% CI -0.090 to -0.058; p<0.001) and Chinese (β=-0.035; 95% CI -0.051 to -0.019; p<0.001), respectively. Additionally, older age (per decade, β=-0.022), male gender (β=-0.031), longer axial length (per mm, β=-0.025), spherical equivalent (per negative dioptre, β=-0.005), higher IOP (per mm Hg, β=-0.009) were associated with smaller RA (all p≤0.004). Conclusion In this multiethnic population-based study, we observed significantly smaller RA in Indian eyes, compared with Chinese and Malays. This indicates the need of a more refined ethnic-specific RA normative databases among Asians. [ABSTRACT FROM AUTHOR]

Aims To use machine learning (ML) to determine the relative contributions of modifiable and non-modifiable clinical, metabolic, genetic, lifestyle and socioeconomic factors on the risk of major eye diseases. Methods We conducted analyses in a cross-sectional multi-ethnic population-based study (n=10 033 participants) and determined a range of modifiable and nonmodifiable risk factors of common eye diseases, including diabetic retinopathy (DR), non-diabetic-related retinopathy (NDR); early and late age-related macular degeneration (AMD); nuclear, cortical and posterior subcapsular (PSC) cataract; and primary open-angle (POAG) and primary angle-closure glaucoma (PACG). Risk factors included individual characteristics, metabolic profiles, genetic background, lifestyle patterns and socioeconomic status (n~100 risk factors). We used gradient boosting machine to estimate the relative influence (RI) of each risk factor. Results Among the range of risk factors studied, the highest contributions were duration of diabetes for DR (RI=22.1%), and alcohol consumption for NDR (RI=6.4%). For early and late AMD, genetic background (RI~20%) and age (RI~15%) contributed the most. Axial length was the main risk factor of PSC (RI=30.8%). For PACG, socioeconomic factor (mainly educational level) had the highest influence (20%). POAG was the disease with the highest contribution of modifiable risk factors (cumulative RI~35%), followed by PACG (cumulative RI ~30%), retinopathy (cumulative RI between 20% and 30%) and late AMD (cumulative RI ~20%). Conclusion This study illustrates the utility of ML in identifying factors with the highest contributions. Risk factors possibly amenable to interventions were intraocular pressure (IOP) and Body Mass Index (BMI) for glaucoma, alcohol consumption for NDR and levels of HbA1c for DR. [ABSTRACT FROM AUTHOR]

Background/Aims Accurate isolation and quantification of intraocular dimensions in the anterior segment (AS) of the eye using optical coherence tomography (OCT) images is important in the diagnosis and treatment of many eye diseases, especially angleclosure glaucoma. Method In this study, we developed a deep convolutional neural network (DCNN) for the localisation of the scleral spur; moreover, we introduced an information-rich segmentation approach for this localisation problem. An ensemble of DCNNs for the segmentation of AS structures (iris, corneosclera shell adn anterior chamber) was developed. Based on the results of two previous processes, an algorithm to automatically quantify clinically important measurements were created. 200 images from 58 patients (100 eyes) were used for testing. Results With limited training data, the DCNN was able to detect the scleral spur on unseen anterior segment optical coherence tomography (ASOCT) images as accurately as an experienced ophthalmologist on the given test dataset and simultaneously isolated the AS structures with a Dice coefficient of 95.7%. We then automatically extracted eight clinically relevant ASOCT measurements and proposed an automated quality check process that asserts the reliability of these measurements. When combined with an OCT machine capable of imaging multiple radial sections, the algorithms can provide a more complete objective assessment. The total segmentation and measurement time for a single scan is less than 2 s. Conclusion This is an essential step towards providing a robust automated framework for reliable quantification of ASOCT scans, for applications in the diagnosis and management of angle-closure glaucoma. [ABSTRACT FROM AUTHOR]

Myopia is an emerging public health issue with potentially significant economic and social impact, especially in East Asia. However, many uncertainties about myopia and its clinical management remain. The International Myopia Summit workgroup was convened by the Singapore Eye Research Institute, the WHO Regional Office for the Western Pacific and the International Agency for the Prevention of Blindness in 2019. The aim of this workgroup was to summarise available evidence, identify gaps or unmet needs and provide consensus on future directions for clinical research in myopia. In this review, among the many 'controversies in myopia' discussed, we highlight three main areas of consensus. First, development of interventions for the prevention of axial elongation and pathologic myopia is needed, which may require a multifaceted approach targeting the Bruch's membrane, choroid and/or sclera. Second, clinical myopia management requires co-operation between optometrists and ophthalmologists to provide patients with holistic care and a tailored approach that balances risks and benefits of treatment by using optical and pharmacological interventions. Third, current diagnostic technologies to detect myopic complications may be improved through collaboration between clinicians, researchers and industry. There is an unmet need to develop new imaging modalities for both structural and functional analyses and to establish normative databases for myopic eyes. In conclusion, the workgroup's call to action advocated for a paradigm shift towards a collaborative approach in the holistic clinical management of myopia. [ABSTRACT FROM AUTHOR]

Background The ability of deep learning (DL) algorithms to identify eyes with neovascular age-related macular degeneration (nAMD) from optical coherence tomography (OCT) scans has been previously established. We herewith evaluate the ability of a DL model, showing excellent performance on a Korean data set, to generalse onto an American data set despite ethnic differences. In addition, expert graders were surveyed to verify if the DL model was appropriately identifying lesions indicative of nAMD on the OCT scans. Methods Model development data set--12 247 OCT scans from South Korea; external validation data set--91 509 OCT scans from Washington, USA. In both data sets, normal eyes or eyes with nAMD were included. After internal testing, the algorithm was sent to the University of Washington, USA, for external validation. Area under the receiver operating characteristic curve (AUC) and precision-recall curve (AUPRC) were calculated. For model explanation, saliency maps were generated using Guided GradCAM. Results On external validation, AUC and AUPRC remained high at 0.952 (95% CI 0.942 to 0.962) and 0.891 (95% CI 0.875 to 0.908) at the individual level. Saliency maps showed that in normal OCT scans, the fovea was the main area of interest; in nAMD OCT scans, the appropriate pathological features were areas of model interest. Survey of 10 retina specialists confirmed this. Conclusion Our DL algorithm exhibited high performance for nAMD identification in a Korean population, and generalised well to an ethnically distinct, American population. The model correctly focused on the differences within the macular area to extract features associated with nAMD. [ABSTRACT FROM AUTHOR]

Aims To determine the association between albuminuria and primary open-angle glaucoma (POAG). Methods Participants of the Singapore Chinese Eye study were recruited and underwent standardised ocular and systemic examinations. Albuminuria was determined using urinary albumin-to-creatinine ratio (UACR, mg/g) based on random spot urinary albumin and creatinine measurements. POAG was defined using the International Society of Geographic and Epidemiological Ophthalmology classification. Multivariable logistic regression with generalised estimating equation model was used to evaluate the association between albuminuria and POAG, while accounting for correlation between eyes. Results A total of 3009 Chinese adults (5963 eyes), aged 40-80 years, were included in this study, of which, 52 subjects (75 eyes) had POAG. Higher UACR (per 50 mg/g increase) was independently associated with POAG (OR=1.04, 95% CI 1.01 to 1.07, p=0.003) following adjustment for age, gender, intraocular pressure, diabetes mellitus, hyperlipidaemia, hypertension, anti-hypertensive medication, history of cardiovascular disease, current smoking status, alcohol intake, body mass index and estimated glomerular filtration rate. Further stratification revealed that individuals with macroalbuminuria were 8.00 times likely to have POAG (95% CI 2.97 to 21.54, p<0.001), compared with those with normoalbuminuria. Microalbuminuria was not significantly associated with POAG (OR=0.49, 95% CI 0.19 to 1.29, p=0.150). The association between macroalbuminuria and POAG remained significant among individuals who were diabetic (OR=9.89, 95% CI 2.49 to 39.30, p=0.001) and hypertensive (OR=8.39, 95% CI 3.07 to 22.94, p<0.001). Conclusion In this population-based study of Chinese adults, albuminuria was independently associated with POAG. Our findings provide further understanding on the pathogenesis of POAG and may potentially help to better identify individuals at risk of POAG. [ABSTRACT FROM AUTHOR]

Purpose We examined the longitudinal association of baseline alcohol intake and frequency with the 6-year incidence and progression of diabetic retinopathy (DR) in a population-based cohort of Singaporean Indians. Methods We included 656 participants with diabetes mellitus, gradable retinal photographs from baseline (2007-2009) and follow-up (2013-2015) examinations, information on alcohol intake and other relevant data from the Singapore Indian Eye Study were included. Incident DR was defined using the Modified Airlie House Classification as no DR at baseline and at least minimal non-proliferative DR at follow-up; and DR progression as at least a one-step worsening in DR at follow-up from minimal or worse status at baseline, excluding those with proliferative DR. Results The mean age (SD) of our participants (n=656) was 58.8 (9.2) years, and 54.4% were male. At follow-up, 82 of 510 (16%) participants developed DR, and 45 of 146 (30.8%) had DR progression. 65 (12.7%) and 28 (19.1%) participants consumed alcohol in incident DR and progression categories, respectively. In multivariable analyses, those who consumed alcohol had nearly two-thirds reduced odds of incident DR (OR (95% CI): 0.36 (0.13 to 0.98)) compared with those who did not. Participants with infrequent consumption of alcohol also had a reduction in odds of incident DR (0.17 (0.04 to 0.69)), compared with non-drinkers. No association was found between alcohol consumption and DR progression. Conclusions and relevance In our longitudinal population of Singapore Indians, baseline alcohol intake, particularly infrequent consumption, was associated with lower risk of developing DR, compared with non-drinkers, in line with previous cross-sectional findings. [ABSTRACT FROM AUTHOR]

Purpose To investigate the characteristics, risk factors and visual impact of myopic traction maculopathy (MTM) among adults with myopia in Singapore. Methods We analysed 3316 myopic eyes of adults aged over 40 years who participated in the Singapore Epidemiology of Eye Diseases-2 study. Detailed questionnaires and ophthalmic examinations were conducted. A total of 2913 myopic eyes of 1639 subjects were graded for MTM by spectral-domain optical coherence tomography. MTM is defined as the presence of retinoschisis, lamellar or full-thickness macula hole and foveal retinal detachment. Fundus photographs were graded for myopic macular degeneration (MMD). Results Of these 2913 myopic eyes, the mean and SD of age was 60.1±8.0 years; the spherical equivalent (SE) was -2.5±2.3 D; and the axial length (AL) was 24.6±1.3?mm. MTM was found in 0.9% of myopic eyes and 7.3% of highly myopic eyes. In the multivariate analysis, myopic SE (p<0.001), longer AL (p<0.001), MMD (p=0.01) and epiretinal traction (p<0.001) were independent risk factors for MTM. MTM was not associated with age (p=0.38). MTM was significantly associated with poorer best-corrected visual acuity (BCVA) (p<0.01). Conclusions Our population-based study revealed that MTM was present in 0.9% of myopic eyes and 7.3% of highly myopic eyes. While greater myopic SE, longer AL, MMD and epiretinal traction are risk factors of MTM, age was not related to MTM. MTM has a negative effect on BCVA. [ABSTRACT FROM AUTHOR]

Background To investigate the longitudinal associations between person-level and area-level socioeconomic status (PLSES and ALSES, respectively) with diabetic retinopathy (DR) and visual impairment (VI) in Asians with diabetes mellitus (DM). Methods In this population-based cohort study, we included 468 (39.4%) Malays and 721 (60.6%) Indians with DM, with a mean age (SD) of 58.9 (9.1) years; 50.6% were female and the mean follow-up duration was 6.2 (0.9) years. Individual PLSES parameters (education, monthly income and housing type) were quantified using questionnaires. ALSES was assessed using the Socioeconomic Disadvantage Index derived from Singapore's 2010 areal census (higher scores indicate greater disadvantage). Incident DR and VI were defined as absent at baseline but present at follow-up, while DR and VI progression were defined as a ≥1 step increase in severity category at follow-up. Modified Poisson regression analysis was used to determine the associations of PLSES and ALSES with incidence and progression of DR and VI, adjusting for relevant confounders. Results In multivariable models, per SD increase in ALSES score was associated with greater DR incidence (risk ratio (95% CI) 1.27 (1.13 to 1.44)), DR progression (1.10 (1.00 to 1.20)) and VI incidence (1.10 (1.04 to 1.16)), while lower PLSES variables were associated with increased DR (low income: 1.68 (1.21 to 2.34)) and VI (low income: 1.44 (1.13 to 1.83); ≤4 room housing: 2.00 (1.57 to 2.54)) incidence. Conclusions We found that both PLSES and ALSES variables were independently associated with DR incidence, progression and associated vision loss in Asians. Novel intervention strategies targeted at low socioeconomic status communities to decrease rates of DR and VI are warranted. [ABSTRACT FROM AUTHOR]

Background/aims To identify factors that influence the diagnostic performance of circumpapillary retinal nerve fibre layer (RNFL) thickness measurements in the detection of primary open-angle glaucoma (POAG). Methods 1592 eyes from 1076 healthy controls and 758 eyes from 502 patients with POAG underwent optical coherence tomography (OCT) imaging to assess RNFL parameters. Visual field (VF) mean deviation (MD) from standard automated perimetry was used to indicate severity in subjects with glaucoma. Results RNFL thickness significantly decreased with age (ρ=-0.10 to -0.16, p<0.001) and increased with spherical equivalent (SE) refractive error (ρ=0.23-0.29, p<0.001) in healthy and glaucoma groups but showed a significant reduction with SE (ρ=-0.20, p<0.001) in the temporal RNFL of healthy subjects. RNFL measurements significantly decreased with VF MD (ρ=0.08-0.53, p<0.05) in subjects with POAG. When healthy subjects and subjects with glaucoma were matched to subgroups within a factor, significant differences in area under the curve (AUC) between subgroups were only found with SE AUCs increased significantly with disease severity, particularly in the global, inferior and superior measurements (p<0.001). Overall, the diagnostic performance of the inferior and global RNFL measurements were found to be more resilient to different factors. Conclusion Diagnostic accuracy in glaucoma was influenced by SE but could be mitigated by using controls with similar refractive characteristics. Increasing disease severity led to significantly better diagnostic accuracy. These factors should be considered when using OCT for glaucoma diagnosis in practice. [ABSTRACT FROM AUTHOR]

Aim To investigate the determinants of lamina cribrosa depth (LCD) in healthy eyes of Chinese and Indian Singaporean adults. Methods The optic nerve head (ONH) of the right eye of 1396 subjects (628 Chinese and 768 Indian subjects) was imaged with optical coherence tomography (OCT, Spectralis, Heidelberg, Germany). LCD was defined as the distance from the Bruch's membrane opening (LCD-BMO) or the peripapillary sclera (LCD-PPS) reference plane to the laminar surface. A linear regression model was used to evaluate the relationship between the LCD and its determinants. Results Both LCDs were significantly different between the two races (LCD-BMO: 421.95 (95% CI 365.32 to 491.79) μm in Chinese vs 430.39 (367.46-509.81) μm in Indians, p=0.021; and LCD-PPS: 353.34 (300.98-421.45) μm in Chinese vs 376.76 (313.39-459.78) μm in Indians, p<0.001). In the multivariable regression analysis, the LCD-PPS of the whole cohort was independently associated with females (β=-31.93, p<0.001), Indians subjects (β=21.39, p=0.004) (Chinese as the reference), axial length (Axl) (β=-6.68, p=0.032), retinal nerve fibre layer thickness (RNFL) (β=0.71, p=0.019), choroidal thickness (ChT) (β=0.41, p<0.001), vertical cup disc ratio (VCDR) (β=24.42, p<0.001) and disc size (β=-60.75, p=0.001). For every 1 year older in age, the LCD-PPS was deeper on average by 1.95 μm in Chinese subjects (p=0.01) but there was no association in Indians subjects (p=0.851). Conclusions The LCD was influenced by age, gender, race, Axl, RNFL, ChT, VCDR and disc size. This normative LCD database may facilitate a more accurate assessment of ONH cupping using OCT in Asian populations. [ABSTRACT FROM AUTHOR]

Background/aims As swept-source optical coherence tomography (SS-OCT) simultaneously obtains 128 meridional scans, it is important to identify which scans are playing the main role in classifying gonioscopic angle closure to simplify the analysis. We aimed to evaluate the diagnostic performance of every meridional scan in its ability to detect gonioscopic angle closure. Methods Observational study with 2027 phakic subjects consecutively recruited from a community polyclinic. Gonioscopy and SS-OCT were performed. Gonioscopic angle closure was defined as non-visibility of the posterior trabecular meshwork in â¥180° of the angle, while SS-OCT was defined as iridotrabecular contact anterior to the scleral spur. The area under the receiver operating characteristic curve (AUC) was calculated to assess the diagnostic performance of each single scan, the sequential anticlockwise cumulative effect of those single scans and different combinations of them. Results The AUCs of each scan ranged from 0.73 to 0.82. The single scan at 80°-260° had the highest AUC (0.82, 95% CI 0.79 to 0.84) and performed significantly better than most of the temporonasal scans (from 0° to 52° and from 153° to 179°). The superoinferior scans achieved higher AUCs compared with the temporonasal ones. When assessing the cumulative effect of adding individual scans consecutively, the peak AUC (0.80) was obtained when considering the superoinferior scans closer to 80°-85°, but no further positive cumulative effect was seen when adding the rest of the temporonasal scans of the circumference. Conclusions In conclusion, the single SS-OCT scan at 80°-260° had the highest diagnostic performance. Our study suggests that the 360° evaluation may not translate to better clinical utility for detection of gonioscopic angle closure. [ABSTRACT FROM AUTHOR]

Glaucoma is a leading cause of irreversible visual impairment, and primary angle closure glaucoma (PACG) affects Asians disproportionately. Whereas advances in ocular imaging have identified several anatomical risk factors, our ability to predict PACG still requires considerable improvement. The iris plays a crucial role in the pathophysiology of angle closure disease, either through a mechanical or vascular mechanism. Irises of closed-angle eyes inhibit vastly different structural constituents as compared with those of open-angle eyes, thereby effecting variations in biomechanical properties and iris fluid conductivity. The clinical consequences include a smaller change in iris volume on pupil dilation in closed-angle eyes, thereby bringing the iris and trabecular meshwork closer in apposition. In this review, we summarise the potential role of the iris in the pathogenesis of angle closure disease. [ABSTRACT FROM AUTHOR]

Background/Aim To investigate normative patterns and factors associated with presbyopia progression in a multiethnic Asian population. Methods Malay, Indian and Chinese participants aged 40–80 years who had baseline and 6-year follow-up examinations with subjective refraction data were recruited from the Singapore Epidemiology of Eye Diseases Study. Presbyopia progression was defined as an increase in near addition power of ≥+0.50 dioptre (D) from baseline to follow-up visit. Modified Poisson regression analyses were used to determine baseline factors associated with presbyopia progression. Results From the eligible 3974 eyes, 2608 eyes were included for final analysis after excluding eyes with a history of cataract surgery (929 eyes) and best-corrected distance visual acuity worse than 20/40 (342 eyes). Overall the mean near addition power change over 6 years was +0.25 D; Malays showed greater change (+0.37 D) compared with Indians (+0.23 D) and Chinese (+0.16 D). After adjusting for baseline age, gender, body mass index, hypertension, cataract, refractive error and daily hours of reading and writing, Malays were more likely to have presbyopia progression compared with Chinese (RR (relative risk)=1.67; 95%CI 1.43 to 1.95; p<0.001) and Indians (RR=1.45; 95%CI 1.25 to 1.68; p<0.001). Individuals aged 60–69 years (RR=0.77; p=0.006) and ≥70 years (RR=0.51; p<0.001) were less likely to progress in presbyopia compared with those aged 40–49. Conclusion In this Asian population, the near addition power change over 6 years was lower than the current near addition prescription guidelines (+0.25 D vs +0.60 D). Our findings may help update near addition prescription guidelines that can be more tailored to Asians. [ABSTRACT FROM AUTHOR]

Purpose To evaluate posterior eye shape variations across a wide refractive error range using brain MRI in a multiethnic cohort. Methods Adult subjects in the multiethnic Singapore Epidemiology of Eye Disease study were included. Spherical equivalent (SE) was measured using subjective refraction, and axial length (AL) was measured using optical biometry. MRI was performed using a 3-Tesla whole body scanner with a 32-channel head coil. The radii and asphericity based on fitting of the posterior twothirds of the eye (240°) were calculated. The refractive error status was categorised as myopic (SE<-0.5 D) or non-myopic (SE≥-0.5 D). Results A total of 450 adult participants (mean age 64.2±6.5 years old) were included. Less oblate asphericity was associated with more myopic SE, longer AL and with a refractive error categorisation of myopia (p<0.001 for all). Asphericity values were less oblate in myopic compared with non-myopic eyes (p<0.001). Multivariate analysis showed that Chinese subjects had less oblate eyes than Malay and Indian subjects, especially in non-myopic eyes. Conclusions A less oblate posterior eye shape was associated with myopic eyes. Chinese eyes have less oblate shapes than Malay and Indian eyes, especially in non-myopic eyes. [ABSTRACT FROM AUTHOR]

Background To examine the normative profile and determinants of retinal nerve fibre layer (RNFL) symmetry in a non-glaucoma, multiethnic Asian population.///Methods Chinese, Malay and Indian adults aged ≥ 40 years were recruited from the Singapore Epidemiology of Eye Diseases study. Participants underwent standardised systemic and ocular examinations. RNFL thickness was obtained using a spectral-domain optical coherence tomography (Cirrus HD-OCT). RNFL symmetry (in %) was calculated based on Pearson correlation coefficient between the RNFL thickness profiles of the right and left eyes. Multivariable linear regression analysis was used to investigate the associations between ocular and systemic factors with RNFL symmetry.///Results 4211 participants (1227 Chinese, 1245 Malays, 1739 Indians) were included. The mean RNFL symmetry was 86.7%±8.5% in Chinese, 84.7%±10.2% in Malays and 84.0%±10.7% in Indians. The fifth percentile limit of RNFL symmetry was 71.2% in Chinese, 65.0% in Malays and 62.0% in Indians. In multivariable analysis adjusting for age, gender, ethnicity, hypertension, diabetes, hyperlipidaemia, intereye absolute differences in intraocular pressure (IOP), axial length and disc area, Malays (β=-0.9; p=0.03) and Indians (β=-1.76; p<0.001) were found to have lower RNFL symmetry compared with Chinese. Older age, greater intereye differences in IOP, axial length and disc area were significantly associated with lower RNFL symmetry (all p≤0.003).///Conclusions In non-glaucoma individuals, intereye RNFL profile is less symmetric in Malays and Indians than that in Chinese. This also suggests that current commercial optical coherence tomography's deployment of a single, universal RNFL symmetry cut-off for glaucoma detection is flawed, and ethnic-specific cut-off is warranted. [ABSTRACT FROM AUTHOR]

Background/aims Although being a more objective tool for assessment and follow-up of angle closure, reliability studies have reported a moderate diagnostic performance for anterior segment optical coherence tomography (OCT) technologies when comparing with gonioscopy as the reference standard. We aim to determine factors associated with diagnostic disagreement in angle closure when assessed by anterior segment swept source OCT (SS-OCT, CASIA SS-1000; Tomey, Nagoya, Japan) and gonioscopy.///Methods Cross-sectional study. A total of 2027 phakic subjects aged ≥50 years, with no relevant previous ophthalmic history, were consecutively recruited from a community polyclinic in Singapore. Gonioscopy and SS-OCT (128 radial scans) for the entire circumference of the angle were performed for each subject. A two-quadrant closed gonioscopic definition was used. On SS-OCT images, angle closure was defined as iridotrabecular contact (ITC) to the extent of ≥35%, ≥50% and ≥75% of the circumferential angle. Diagnostic disagreements between both methods, that is, false positives or overcalls and false negatives or undercalls were defined, respectively, as gonioscopic open/closed angles inversely assessed as closed/open by SS-OCT.///Results Two hundred and seventy-two (14.7%) resulted in overcall results (false positives) when ≥ 50% of the angle circumference was closed using SS-OCT. These eyes had significantly wider (anterior chamber width, 11.7 vs 11.6 mm, p<0.001) and deeper (anterior chamber depth (ACD), 2.4 vs 2.2 mm, p<0.001) anterior chambers than eyes assessed by both methods as closed (true positives). Deeper ACD (OR 9.31) and lower lens vault (LV) (OR 0.04) were significantly associated with a false positive diagnosis in the multivariate analysis. Most of these cases had short (52.6%) or irregular (39%) ITC in SS-OCT images.///Conclusions We found that anterior chamber dimensions, determined by ACD and LV, were factors significantly associated with diagnostic disagreement between anterior segment SS-OCT and gonioscopy in angle closure assessment. [ABSTRACT FROM AUTHOR]

Background To determine the prevalence and causes of blindness and vision impairment (VI) in East Asia in 2015 and to forecast the trend to 2020. Methods Through a systematic literature review and meta- analysis, we estimated prevalence of blindness (presenting visual acuity <3/60 in the better eye), moderate- to- severe vision impairment (MSVI; 3/60≤presenting visual acuity <6/18), mild vision impairment (mild VI: 6/18≤presenting visual acuity <6/12) and uncorrected presbyopia for 1990, 2010, 2015 and 2020. A total of 44 population- based studies were included. Results In 2015, age- standardised prevalence of blindness, MSVI, mild VI and uncorrected presbyopia was 0.37% (80% uncertainty interval (UI) 0.12%--0.68%), 3.06% (80% UI 1.35%--5.16%) and 2.65% (80% UI 0.92%--4.91%), 32.91% (80% UI 18.72%--48.47%), respectively, in East Asia. Cataract was the leading cause of blindness (43.6%), followed by uncorrected refractive error (12.9%), glaucoma, age- related macular degeneration, corneal diseases, trachoma and diabetic retinopathy (DR). The leading cause for MSVI was uncorrected refractive error, followed by cataract, age- related macular degeneration, glaucoma, corneal disease, trachoma and DR. The burden of VI due to uncorrected refractive error, cataracts, glaucoma and DR has continued to rise over the decades reported. Conclusions Addressing the public healthcare barriers for cataract and uncorrected refractive error can help eliminate almost 57% of all blindness cases in this region. Therefore, public healthcare efforts should be focused on effective screening and effective patient education, with access to high- quality healthcare. [ABSTRACT FROM AUTHOR]

background/aims In order to address the eye care needs of the increasing numbers of elderly Chinese globally, there is a need for comprehensive understanding on the longitudinal trends of age- related eye diseases among Chinese. We herein report the key findings from the baseline Singapore Chinese Eye Study (SCES-1), and describe the rationale and methodology of the 6- year follow- up study (SCES-2). Methods 3353 Chinese adults who participated in the baseline SCES-1 (2009--2011) were invited for the 6- year follow- up SCES-2 (2015--2017). Examination procedures for SCES-2 included standardised ocular, systemic examinations and questionnaires identical to SCES-1. SCES-2 further included new examinations such as optical coherence tomography angiography, and questionnaires to evaluate health impact and economic burden of eye diseases. results In SCES-1, the age- adjusted prevalence of bestcorrected low vision (VA<6/12, better- seeing eye) and blindness (VA<6/60, better- seeing eye) were 3.4% and 0.2%, respectively. The prevalence rates for glaucoma, age related macular degeneration, and diabetic retinopathy (among diabetics) were 3.2%, 6.8%, 26.2%, respectively. Of the 3033 eligible individuals from SCES- 1, 2661 participated in SCES-2 (response rate=87.7%). Comparing with those who did not attend SCES-2, those attended were younger, had higher SES (all p<0.001), but less likely to be a current smoker, to have diabetes, hypertension, hyperlipidaemia (all p≤0.025). Conclusions Building on SCES-1, SCES-2 will be one of the few longitudinal population- based eye studies to report incidence, progression, and risk factors of major age- related eye diseases. Findings from this cohort may offer new insights, and provide useful reference information for other Chinese populations elsewhere. [ABSTRACT FROM AUTHOR]

Background/aims To evaluate the association between systemic medications and cortical cataract prevalence in an Asian population. Methods The Singapore Epidemiology of Eye Diseases Study recruited 10 033 Chinese, Malay and Indian residents aged 40+ years living in Singapore. Information on medication use was collected at interview using questionnaires. The presence and severity of cortical cataract were assessed from lens photographs using the modified Wisconsin Cataract Grading System. Associations between medications and the presence of cortical cataract were assessed using logistic regression. Associations between medications and greater severity of cortical cataract (none, minimal, early and late) were assessed using ordinal logistic regression. Results A total of 8965 participants were included, the mean age was 57.6 (SD=9.8) years, and 4555 (50.8%) were women. After adjusting for age, gender, ethnicity, body mass index, smoking status, socioeconomic status, hypertension, hyperlipidaemia, diabetes, duration of diabetes and cardiovascular disease, ACE inhibitors (OR=1.27; 95% CI 1.05 to 1.55), fibrates (OR=1.57; 95% CI 1.05 to 2.35), alpha-glucosidase inhibitors (AGIs) (OR=1.85; 95% CI 1.13 to 3.02) and insulin (OR=1.80; 95% CI 1.11 to 2.93) were significantly associated with the presence of cortical cataract. Further adjusting for concurrent medication use did not alter these associations. Consistently, the four medications were also associated with a greater severity level of cortical cataract. Conclusion ACE inhibitors, fibrates and AGIs were associated with increased prevalence of cortical cataract in this Asian population, independent of the presence of hypertension, hyperlipidaemia and diabetes, respectively. Whether they contribute to the risk of cortical cataract needs confirmation in longitudinal studies. [ABSTRACT FROM AUTHOR]

Background/Aims To compensate the retinal nerve fibre layer (RNFL) thickness assessed by spectral-domain optical coherence tomography (SD-OCT) for anatomical confounders. Methods The Singapore Epidemiology of Eye Diseases is a population-based study, where 2698 eyes (1076 Chinese, 704 Malays and 918 Indians) with high-quality SD-OCT images from individuals without eye diseases were identified. Optic disc and macular cube scans were registered to determine the distance between fovea and optic disc centres (fovea distance) and their respective angle (fovea angle). Retinal vessels were segmented in the projection images and used to calculate the circumpapillary retinal vessel density profile. Compensated RNFL thickness was generated based on optic disc (ratio, orientation and area), fovea (distance and angle), retinal vessel density, refractive error and age. Linear regression models were used to investigate the effects of clinical factors on RNFL thickness. Results Retinal vessel density reduced significantly with increasing age (1487±214 µm in 40-49, 1458±208 µm in 50-59, 1429±223 µm in 60-69 and 1415±233 µm in >70). Compensation reduced the variability of RNFL thickness, where the effect was greatest for Chinese (10.9%; p<0.001), followed by Malays (6.6%; p=0.075) and then Indians (4.3%; p=0.192). Compensation reduced the age-related RNFL decline by 55% in all participants (β=-3.32 µm vs β=-1.50 µm/10 years; p<0.001). Nearly 62% of the individuals who were initially classified as having abnormally thin RNFL (outside the 99% normal limits) were later reclassified as having normal RNFL. Conclusions RNFL thickness compensated for anatomical parameters reduced the variability of measurements and may improve glaucoma detection, which needs to be confirmed in future studies. [ABSTRACT FROM AUTHOR]