Tien Y Wong

Centre for Eye Research Australia, Melbourne, Victoria, Australia

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Publications (405)2558.65 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose This study investigated the responses of retinal vessels to flickering light in diabetic patients with various stages of diabetic retinopathy (DR). Methods This cross-sectional observational study evaluated adult subjects with diabetes mellitus. The Dynamic Vessel Analyser (DVA) was used to measure retinal vascular dilatation in response to diffuse illuminance flicker. DR was graded from retinal photography. Results There were 279 subjects in total, with a mean age of 59.9±9.2 years. The majority were male (73%) and the mean HbA1c level and mean duration of diabetes were 7.7±1.4% and 13.9±10.4 years respectively. After adjustments for age, sex, smoking, duration of diabetes, HbA1c, hypertension and hyperlipidemia, the responses of both retinal arterioles and venules to flicker stimulation decreased continuously with increasing stages of diabetic retinopathy.(p = 0.008 and <0.001 respectively). Subjects with reduced arteriolar dilation responses were more likely to have any DR [odds ratio, OR, 1.20, (95% confidence interval, CI, 1.01 - 1.45), p=0.045, per standard deviation (SD) decrease]. Subjects with reduced venular dilation responses were more likely to have any DR, moderate DR or vision-threatening DR [OR 1.27(1.04 - 1.53), p=0.02; OR1.27 (1.06 - 1.49), p = 0.007; and OR1.51(1.14 - 1.50), p = 0.002; per SD decrease, respectively]. Conclusion The responses of retinal arterioles and venules to flickering light are reduced in subjects with DR, and decrease progressively with more severe stages of DR.
    Investigative ophthalmology & visual science. 07/2014;
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    ABSTRACT: Choroidal neovascularisation (CNV) is a common vision-threatening complication of myopia and pathological myopia. Despite significant advances in understanding the epidemiology, pathogenesis and natural history of myopic CNV, there is no standard definition of myopic CNV and its relationship to axial length and other myopic degenerative changes. Several treatments are available to ophthalmologists, but with the advent of new therapies there is a need for further consensus and clinical management recommendations. Verteporfin photodynamic therapy has been an established treatment for subfoveal myopic CNV for many years, but this treatment does not restore visual acuity and is associated with long-term chorioretinal atrophy. More recently, clinical trials investigating the efficacy and safety of anti-vascular endothelial growth factor agents in patients with myopic CNV have demonstrated substantial visual acuity gains and quality of life increases compared with photodynamic therapy. These enhanced outcomes provide updated evidence-based clinical management guidelines of myopic CNV, and increase the need for a generally accepted definition for myopic CNV. This review critically summarises the latest myopic CNV literature in the context of clinical experience and recommends a myopic CNV treatment algorithm.
    The British journal of ophthalmology. 07/2014;
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    ABSTRACT: Glaucoma is the leading cause of global irreversible blindness. Present estimates of global glaucoma prevalence are not up-to-date and focused mainly on European ancestry populations. We systematically examined the global prevalence of primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG), and projected the number of affected people in 2020 and 2040.
    Ophthalmology 06/2014; · 5.56 Impact Factor
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    ABSTRACT: Purpose: To compare early age-related macular degeneration (AMD) lesion characteristics between white Australians and Singaporean Asians. Methods: Participants of the Blue Mountains Eye Study (BMES; whites, n=3508) and the Singapore Epidemiology of Eye Disease Study (SEED, Malay, n=3280, Indian, n=3400 and Chinese, n=3353) underwent examinations including retinal photography. AMD lesions were assessed following the Wisconsin AMD grading protocol by the same photographic grader. Prevalence and characteristics of early AMD lesions were compared between the BMES and the SEED. The associations between ethnicity and early AMD lesion types were analyzed using logistic regression models adjusting for age, sex, smoking status, lipids and genetic polymorphisms associated with AMD. Results: After age-standardization to the BMES population, the prevalence of distinct soft drusen was significantly higher in Singaporeans compared to Australians (23.9%, 95% confidence interval (CI) 22.9-25.0 versus 6.2%, 95% CI 5.3-7.0), with an adjusted odds ratio (OR) 4.6 (95% CI 3.4-6.0). In contrast, the prevalence of indistinct soft or reticular drusen was significantly lower in Singaporeans compared to Australians (6.5%, 95% CI 5.9-7.1 versus 8.3%, 95% CI 7.4-9.3, with non-significant adjusted OR 1.2, 95% CI 0.8-1.7). Soft drusen of any type were frequently present at the inner and outer macula (within a zone ≥500µm to <3000µm radius from the foveal centre) among Singaporeans, while among Australians soft drusen were more frequently present at the central macula (<500µm radius). Conclusion: Singaporean Asians had a milder spectrum of early AMD lesions and lesion characteristics (predominantly distinct soft drusen and non-central location) compared to white Australians.
    Investigative ophthalmology & visual science. 06/2014;
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    ABSTRACT: Diabetic neuropathy, nephropathy and retinopathy cause significant morbidity in patients with type 1 diabetes, even though improvements in treatment modalities delay the appearance and reduce the severity of these complications. To prevent or further delay the onset, it is necessary to better understand common underlying pathogenesis and to discover pre-clinical biomarkers of these complications.Retinal vessel calibers have been associated with the presence of microvascular complications but their long-term predictive value has only been sparsely investigated.We examined retinal vessel calibers as 16-year predictors of diabetic nephropathy, neuropathy and proliferative retinopathy in a young population-based Danish cohort with type 1 diabetes. We used semi-automated computer software to analyze vessel diameters on baseline retinal photos. Calibers of all vessels coursing through a zone 0.5-1 disc diameter from the disc margin were measured and summarized as the central artery and vein equivalents.In multiple regression analyzes we found both wider venular diameters and smaller arteriolar diameters to be predictive of the 16-year development of nephropathy, neuropathy and proliferative retinopathy. Early retinal vessel caliber changes are seemingly early markers of microvascular processes, precede the development of microvascular complications and a potential non-invasive predictive test on future risk of diabetic retinopathy, neuropathy and nephropathy.
    Diabetes 06/2014; · 7.90 Impact Factor
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    ABSTRACT: Common variation at the 11p11.2 locus, encompassing MADD, ACP2, NR1H3, MYBPC3, and SPI1, has been associated in genome-wide association studies with fasting glucose and insulin (FI). In the Cohorts for Heart and Aging Research in Genomic Epidemiology Targeted Sequencing Study, we sequenced 5 gene regions at 11p11.2 to identify rare, potentially functional variants influencing fasting glucose or FI levels.
    Circulation Cardiovascular Genetics 06/2014; 7(3):374-82. · 6.73 Impact Factor
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    ABSTRACT: Body mass index (BMI) is an established risk factor for diabetes. However, the association between BMI and diabetic retinopathy (DR) has been inconclusive. We aimed to assess the association between BMI and DR in a large population-based sample of multi-ethnic Asian adults in Singapore. We examined 2,278 adults aged ≥40 years with diabetes who participated in three population-based studies conducted from 2004 to 2011: the Singapore Malay Eye Study, the Singapore Indian Eye Study, and the Singapore Chinese Eye Study. Retinal photographs taken from both eyes were graded for any and vision-threatening (VTDR) using the modified Airlie House Classification. BMI (kg/m(2)) was categorized into normal/underweight (<25), overweight (25-29.9), and obese (≥30). The prevalence rates of any and VTDR in the study population were 35.1 % and 9.1 %, respectively. The prevalence of any and VTDR decreased with increasing categories of BMI (P trend <0.001 and 0.005). In multivariable models adjusted for potential confounders, compared to those with normal weight, the odds ratio (95 % confidence interval) of any DR was 0.71 (0.57-0.88) for overweight and 0.70 (0.53-0.92) for obese. Corresponding estimates for VTDR were 0.84 (0.59-1.21) for overweight and 0.58 (0.35-0.94) for obese. The inverse association between BMI and any DR was consistently present when BMI was analyzed as a continuous variable and in analyses stratified by ethnicity and age. In a population-based sample of multi-ethnic Asian adults, BMI levels were inversely associated with any DR and VTDR.
    Acta diabetologica. 06/2014;
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    ABSTRACT: Age-related macular degeneration (AMD) and chronic kidney disease both involve immune dysregulation and may share underlying pathophysiologic changes to systemic homeostasis. Hence, we aim to evaluate associations between impaired kidney function and early AMD, in a search for urinary biomarkers for AMD.
    Optometry and vision science: official publication of the American Academy of Optometry 05/2014; · 1.53 Impact Factor
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    ABSTRACT: Few studies have examined the impact of chronic kidney disease (CKD) on adverse cardiovascular outcomes and deaths in Asian populations. We evaluated the associations of CKD with cardiovascular disease (CVD) and all-cause mortality in a multi-ethnic Asian population.
    European Journal of Preventive Cardiology 05/2014; · 3.90 Impact Factor
  • Ning Cheung, Ian Y Wong, Tien Y Wong
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    ABSTRACT: Ocular anti-vascular endothelial growth factor (VEGF) therapy represents one of the most significant advances in modern medicine. The introduction and widespread use of ocular anti-VEGF therapy for age-related macular degeneration heralded a new era in the treatment of vascular and exudative diseases of the retina. Its expanding indications now include diabetic macular edema and proliferative diabetic retinopathy, two vision-threatening forms of diabetic retinopathy. It is widely anticipated that ocular anti-VEGF therapy could spark a dramatic shift in the treatment paradigm for diabetic retinopathy. However, despite its clear efficacy shown in clinical trials, the dynamic landscape of evolving medical, ethical, and economic issues related to this new treatment suggests significant challenges ahead. In this article, we provide a discussion of this topic as part of this two-part Bench to Clinic narrative. Here, our Clinic contribution provides an overview of the current evidence from clinical trials on anti-VEGF therapy for diabetic retinopathy, and highlights the hopes and fears of this new treatment from clinical and public health standpoints. In the Bench narrative that precedes this contribution, Simó et al. provide an overview of the role of VEGF in the pathogenesis of diabetic retinopathy.
    Diabetes care 04/2014; 37(4):900-5. · 7.74 Impact Factor
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    ABSTRACT: To assess prevalence and causes of blindness and vision impairment in high-income regions and in Central/Eastern Europe in 1990 and 2010. Based on a systematic review of medical literature, prevalence of moderate and severe vision impairment (MSVI; presenting visual acuity <6/18 but ≥3/60 in the better eye) and blindness (presenting visual acuity <3/60) was estimated for 1990 and 2010. Age-standardised prevalence of blindness and MSVI decreased from 0.2% to 0.1% (3.314 million to 2.736 million people) and from 1.6% to 1.0% (25.362 million to 22.176 million), respectively. Women were generally more affected than men. Cataract was the most frequent cause of blindness in all subregions in 1990, but macular degeneration and uncorrected refractive error became the most frequent causes of blindness in 2010 in all high-income countries, except for Eastern/Central Europe, where cataract remained the leading cause. Glaucoma and diabetic retinopathy were fourth and fifth most common causes for blindness for all regions at both times. Uncorrected refractive error, followed by cataract, macular degeneration, glaucoma and diabetic retinopathy, was the most common cause for MSVI in 1990 and 2010. In highly developed countries, prevalence of blindness and MSVI has been reduced by 50% and 38%, respectively, and the number of blind people and people with MSVI decreased by 17.4% and 12.6%, respectively, even with the increasing number of older people in the population. In high-income countries, macular degeneration has become the most important cause of blindness, but uncorrected refractive errors continue to be the leading cause of MSVI.
    The British journal of ophthalmology 03/2014; · 2.92 Impact Factor
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    ABSTRACT: Diabetic nephropathy (DN) is commonly associated with diabetic retinopathy (DR). Few studies have demonstrated that chronic kidney disease (CKD) is associated with DR. However, it is not clear if CKD in the absence of albuminuria is associated with DR. We included 301 participants with diabetes (Chinese, Malay and Indian ethnicity aged ≥24 years who participated in the Singapore Prospective Study Program (2003-2007). Retinal photographs taken from both eyes were graded for DR using the modified Airlie House Classification. We examined the association of CKD defined by low-eGFR (<60 mL/min/1.73m(2) , n=54), and albuminuria (urinary albumin-to-creatinine ratio ≥30) with any-DR (n=99) in logistic regression models. We replicated this analysis in another independent population-based sample of Malay adults (n=265) with similar methodology in Singapore. 41% of those with low-eGFR had normoalbuminuria. In separate models, while albuminuria was significantly associated with any-DR, low-eGFR was not significantly associated with any-DR. In a model combining both markers, compared to the referent group (normal-eGFR+normoalbuminuria), the OR (95% CI) of any-DR were: 2.33 (1.27-4.27) for normal-eGFR+albuminuria, 1.38 (0.49-3.91) for low-eGFR+normoalbuminuria, and 2.64 (1.05-6.63] for low-eGFR+albuminuria. Similar findings for any-DR were observed in the replication cohort of Malay persons (3.56 [1.49-8.54] for normal-eGFR+albuminuria, 1.69 (0.52-5.55) for low-eGFR+normoalbuminuria, 4.34 [1.68-11.24] for low-eGFR+ albuminuria. We demonstrated that CKD is associated with DR only in the presence of albuminuria suggesting that CKD is more likely related to diabetes in the presence of albuminuria.
    Journal of Diabetes 03/2014; · 2.94 Impact Factor
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    ABSTRACT: Aim To estimate the magnitude, temporal trends and subregional variation in the prevalence of blindness, and moderate/severe vision impairment (MSVI) in sub-Saharan Africa. Methods A systematic review was conducted of published and unpublished population-based surveys as part of the Global Burden of Disease, Risk Factors and Injuries Study 2010. The prevalence of blindness and vision impairment by country and subregion was estimated. Results In sub-Saharan Africa, 52 studies satisfied the inclusion criteria. The estimated age-standardised prevalence of blindness decreased by 32% from 1.9% (95% CI 1.5% to 2.2%) in 1990 to 1.3% (95% CI 1.1% to 1.5%) in 2010 and MSVI by 25% from 5.3% (95% CI 0.2% to 0.3%) to 4.0% (95% CI 0.2% to 0.3%) over that time. However, there was a 16% increase in the absolute numbers with blindness and a 28% increase in those with MSVI. The major causes of blindness in 2010 were; cataract 35%, other/unidentified causes 33.1%, refractive error 13.2%, macular degeneration 6.3%, trachoma 5.2%, glaucoma 4.4% and diabetic retinopathy 2.8%. In 2010, age-standardised prevalence of MSVI in Africa was 3.8% (95% CI 3.1% to 4.7%) for men and 4.2% (95% CI 3.6% to 5.3%) for women with subregional variations from 4.1% (95% CI 3.3% to 5.4%) in West Africa to 2.0% (95% CI 1.5% to 3.3%) in southern Africa for men; and 4.7% (95% CI 3.9% to 6.0%) in West Africa to 2.3% (95% CI 1.7% to 3.8%) in southern Africa for women. Conclusions The age-standardised prevalence of blindness and MSVI decreased substantially from 1990 to 2010, although there was a moderate increase in the absolute numbers with blindness or MSVI. Significant subregional and gender disparities exist.
    The British journal of ophthalmology 02/2014; 98(5):612-618. · 2.92 Impact Factor
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    ABSTRACT: Abstract Purpose: To describe ethnic differences in the distribution of central corneal refractive power and steep cornea in a multiethnic Asian population. Methods: A total of 2968 Chinese, 2957 Indian and 2928 Malay participants aged over 40 years were included in this study. Each subject underwent standardized systematic and ocular examinations, interviewer-administered questionnaires, and blood investigations for risk factor assessment. Central corneal refractive power was measured using an autorefractor. Steep cornea was defined as central corneal refractive power exceeding 48 diopters (D) measured by keratometry. Results: Mean keratometry readings were 43.9 ± 1.5 D in Malays, 44.2 ± 1.5 D in Indians and 43.9 ± 1.5 D in Chinese. The prevalence of steep cornea was 0.6% (95% confidence interval, CI, 0.3-0.9%) in Malays, 1.0% (95% CI 0.7-1.4%) in Indians and 0.5% (95% CI 0.3-0.8%) in Chinese. In multivariate analysis, increasing central corneal refractive power was associated with Indian race, shorter body height, non-smokers, absence of pterygium, shorter axial length, thinner corneas and greater anterior chamber depth, while the presence of steep cornea was significantly associated with Indian race, shorter axial length and thinner corneas. Conclusions: Indian participants had the steepest corneas among the three major ethnic groups in Singapore. Central corneal refractive power was related to several ocular parameters including anterior chamber depth, axial length and central corneal thickness. These data have important clinical implications for understanding the risk of keratoconus.
    Ophthalmic epidemiology 02/2014; · 1.93 Impact Factor
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    ABSTRACT: Objective: To present regional estimates of the magnitude and temporal trends in the prevalence and causes of blindness and moderate/severe visual impairment (MSVI) in Latin America and the Caribbean (LAC). Methods A systematic review of cross-sectional population-representative data from published literature and unpublished studies was accessed and extracted to model the estimated prevalence of vision loss by region, country and globally, and the attributable cause fraction by region. Results: In the LAC combined region, estimated all-age both-gender age-standardised prevalence of blindness halved from 0.8% (0.6 to 1.1) in 1990 to 0.4% (0.4 to 0.6) in 2010 and MSVI decreased from 4.3% (3.1 to 5.3) to 2.7% (2.2 to 3.4). In the Caribbean, estimated all-age both-gender age-standardised prevalence of blindness decreased from 0.6% (0.4 to 0.8) in 1990 to 0.5% (0.4 to 0.6) in 2010 and MSVI decreased from 3.3% (1.3 to 4.1) in 1990 to 2.9% (1.8 to 3.8). In the LAC regions combined, there was an estimated 2.3 million blind and 14.1 million with MSVI in 2010. In 2010, cataract continues to contribute the largest proportion of blindness, except in Southern Latin America where macular degeneration is most common. In 2010, uncorrected refractive error was the most common cause of MSVI. Conclusions: While models suggest a decrease in age-standardised prevalence estimates, better data are needed to evaluate the disparities in the region. The increasing numbers of older people, coupled with the increase in vision loss associated with older age, will require further intervention to continue to reduce prevalence rates and to prevent a rise in absolute numbers of blind.
    The British journal of ophthalmology 02/2014; · 2.92 Impact Factor
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    ABSTRACT: Background: To examine the prevalence, patterns and trends of vision impairment and its causes from 1990 to 2010 in Central and South Asia. Methods: Based on the Global Burden of Diseases Study 2010 and ongoing literature searches, we examined prevalence and causes of moderate and severe vision impairment (MSVI; presenting visual acuity <6/18, ≥3/60) and blindness (presenting visual acuity <3/60). Results: In Central Asia, the estimated age-standardised prevalence of blindness decreased from 0.4% (95% CI 0.3% to 0.6%) to 0.2% (95% CI 0.2% to 0.3%) and of MSVI from 3.0% (95% CI 1.9% to 4.7%) to 1.9% (95% CI 1.2% to 3.2%), and in South Asia blindness decreased from 1.7% (95% CI 1.4% to 2.1%) to 1.1% (95% CI 0.9% to 1.3%) and MSVI from 8.9% (95% CI 6.9% to 10.9%) to 6.4% (95% CI 5.2% to 8.2%). In 2010, 135 000 (95% CI 99 000 to 194 000) people were blind in Central Asia and 10 600 000 (95% CI 8 397 000 to 12 500 000) people in South Asia. MSVI was present in 1 178 000 (95% CI 772 000 to 2 243 000) people in the Central Asia, and in 71 600 000 (95% CI 57 600 000 to 92 600 000) people in South Asia. Women were generally more often affected than men. The leading causes of blindness (cataract) and MSVI (undercorrected refractive error) did not change from 1990 to 2010. Conclusions: The prevalence of blindness and MSVI in South Asia is still three times higher than in Central Asia and globally, with women generally more often affected than women. In both regions, cataract and undercorrected refractive error were major causes of blindness and MSVI.
    The British journal of ophthalmology 01/2014; · 2.92 Impact Factor
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    ABSTRACT: The ATOH7 gene has been previously associated with glaucoma and glaucoma-related traits, such as disc size and cup/disc ratio (CDR). CDR is an important part of the glaucoma phenotype, whereas the relationship between the disc size and the disease is not well understood. The aim of this study was to investigate whether ATOH7 is associated independently with CDR or merely with the size of the optic disc. We carried out an association analysis for a candidate region, including ATOH7 for two populations: the Blue Mountains Eye Study and the TwinsUK cohort. We performed three linear regression models for (1) disc size adjusted on age, sex and intraocular pressure (IOP), (2) CDR adjusted on age, sex and IOP and (3) CDR adjusted on age, sex, IOP and disc size. A strong signal was found at rs7916697 for disc size. This single nucleotide polymorphism (SNP) was also associated with CDR adjusted on age, sex and IOP.However, this SNP was not associated with CDR when adjusted on age, sex, IOP and also disc size. This study finds that ATOH7 is associated with optic disc size but not independently with CDR.
    The British journal of ophthalmology 01/2014; · 2.92 Impact Factor
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    ABSTRACT: To assess iris surface features in Asian eyes and examine their associations with iris thickness measured by anterior segment optical coherence tomography (AS OCT). Cross-sectional study. We recruited 250 subjects from the Singapore Malay Eye Study. We obtained standardized slit-lamp photographs and developed a grading system assessing iris crypts (by number and size), furrows (by number and circumferential extent), and color (higher grade denoting darker iris). Vertical and horizontal cross-sections of the anterior chamber were imaged using AS OCT. Intragrader and intergrader agreements in the grading of iris surface were assessed by weighted κ (κw) statistic. Associations of the average iris thickness with the grade of iris features were assessed using linear regression analysis. Frequency and size of iris crypts, furrows, and color; iris thickness at 750 μm (IT750) and 2000 μm (IT2000) from the scleral spur; and maximum iris thickness (ITM) averaged from the 4 quarters. Three hundred sixty-four eyes had complete and gradable data for crypts and color; 330 eyes were graded for furrows. The grading scheme showed good intragrader (crypt κw = 0.919, furrow κw =0.901, color κw = 0.925) and intergrader (crypt κw = 0.775, furrow κw = 0.836, color κw = 0.718) agreements. Higher crypt grade was associated independently with thinner IT750 (β [change in iris thickness per grade higher] = -0.007; P = 0.029), IT2000 (β = -0.018; P < 0.001), and ITM (β = -0.012; P < 0.001). More extensive furrows were associated with thicker IT750 (β = 0.022; P < 0.001). Darker iris was also associated with thicker IT750 (β = 0.014; P = 0.001). Iris surface features, assessed and measured from slit-lamp photographs, correlate well with iris thickness. Irises with more crypts are thinner; irises with more extensive furrows and darker color are thicker peripherally. These findings may provide another means to assess angle closure risk based on iris features.
    Ophthalmology 01/2014; · 5.56 Impact Factor
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    ABSTRACT: Aims: To describe the prevalence and causes of visual impairment and blindness in East Asia in 1990 and 2010. Method: Data from population-based studies conducted from 1980 to 2012 were identified, and eligibility for inclusion was assessed. Data on prevalence of blindness (presenting visual acuity <3/60 in the better eye) and moderate to severe visual impairment (MSVI; presenting visual acuity <6/18 to 3/60 in the better eye) and causes were extracted. Results: The age-standardised prevalence of blindness was 0.7% (95% CI 0.6 to 0.9) in 1990 and 0.4% (95% CI 0.3 to 0.5) in 2010, while that of MSVI was 3.6% (95% CI 2.3 to 4.4) and 2.3% (95% CI 1.7 to 2.8), respectively. These prevalence estimates were lower than those of other countries globally. The absolute numbers affected by blindness and MSVI in 2010 were 5.2 million and 33.3 million, respectively, and were higher among women than men. Cataract was the leading cause of blindness, whereas uncorrected refractive error was the leading cause of MSVI. Conclusions: There has been a significant reduction in prevalence of blindness in East Asia, but a substantial absolute number of people remain blind and visually impaired, largely caused by cataract and uncorrected refractive error.
    The British journal of ophthalmology 01/2014; · 2.92 Impact Factor
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    ABSTRACT: Objective Retinal microvascular signs are markers of cardiovascular disease risk. There are limited data, on relationships between retinal microvascular signs and retinal microvascular endothelial function. We sought to determine the relationship of retinal vascular signs with retinal microvascular endothelial function in patients with or at high risk of coronary artery disease. Methods Participants with atherosclerosis risk factors and coronary disease (n = 258; mean age 57 ± 11 years) were recruited to have static and dynamic retinal vascular assessment. Retinal arteriolar dilatation in response to flicker light (FI–RAD) was measured using the Digital Vessel Analyser and expressed as percentage increase over baseline diameter. Static retinal photographs were acquired utilising a digital fundus camera for measurement of central retinal artery and vein equivalent (CRAE and CRVE), arteriovenous nicking (AVN) and focal arteriolar narrowing (FAN). Results Intra-class correlation coefficient was 0.82 for flicker-light induced retinal arteriolar dilatation. There were modest associations in retinal vascular measurements between eyes. For each 10 μm decrease in retinal arteriolar diameter, the absolute increase in FI–RAD was 0.28% (95% CI 0.11, 0.45; p = 0.002) independent of age, gender and atherosclerosis risk factors. AVN and FAN were associated with attenuated FI–RAD (β = −0.67%; 95% CI −1.20, −0.15; p = 0.012) and (β = −0.83%; 95% CI −1.44, −0.23; p = 0.007) respectively after adjustment for age and gender. Conclusion Assessment of retinal microvascular endothelial function is reproducible and correlated with retinal microvascular structure and signs, independent of atherosclerosis risk factors. Assessment of retinal vascular structure and function may provide insights into atherosclerotic disease.
    Atherosclerosis 01/2014; 233(2):478–484. · 3.71 Impact Factor

Publication Stats

8k Citations
2,558.65 Total Impact Points


  • 2013–2014
    • Centre for Eye Research Australia
      Melbourne, Victoria, Australia
    • University of Newcastle
      • Centre for Clinical Epidemiology and Biostatistics
      Newcastle, New South Wales, Australia
    • Royal Perth Hospital
      Perth City, Western Australia, Australia
    • Queensland Institute of Medical Research
      Brisbane, Queensland, Australia
  • 2012–2014
    • Duke-NUS Graduate Medical School Singapore
      Tumasik, Singapore
    • Sun Yat-Sen University
      Shengcheng, Guangdong, China
    • The Chinese University of Hong Kong
      • Department of Ophthalmology and Visual Sciences
      Hong Kong, Hong Kong
    • McGill University
      • Department of Epidemiology, Biostatistics and Occupational Health
      Montréal, Quebec, Canada
    • University of North Carolina at Chapel Hill
      • Department of Epidemiology
      Chapel Hill, NC, United States
  • 2008–2014
    • Singapore Eye Research Institute
      Tumasik, Singapore
    • Monash University (Australia)
      • Department of Epidemiology and Preventive Medicine
      Melbourne, Victoria, Australia
    • Swansea University
      Swansea, Wales, United Kingdom
  • 2004–2014
    • University of Melbourne
      • • Centre for Eye Research Australia
      • • Department of Ophthalmology
      Melbourne, Victoria, Australia
  • 2003–2014
    • Singapore National Eye Centre
      Tumasik, Singapore
  • 2007–2013
    • Royal Victorian Eye and Ear Hospital
      Melbourne, Victoria, Australia
    • Diabetes Australia, Victoria
      Melbourne, Victoria, Australia
  • 2006–2013
    • Westmead Millennium Institute
      Sydney, New South Wales, Australia
  • 2005–2013
    • Westmead Hospital
      • Department of Ophthalmology
      Sydney, New South Wales, Australia
  • 2003–2013
    • University of Sydney
      • • Centre for Vision Research
      • • Save Sight Institute
      • • School of Public Health
      Sydney, New South Wales, Australia
  • 2011–2012
    • Khoo Teck Puat Hospital
      Tumasik, Singapore
    • National University Health System
    • Massachusetts Eye and Ear Infirmary
      • Department of Ophthalmology
      Boston, MA, United States
  • 2006–2011
    • National University of Singapore
      • • Department of Ophthalmology
      • • Singapore Eye Research Institute
      Tumasik, Singapore
  • 2003–2011
    • University of Wisconsin, Madison
      • Department of Ophthalmology and Visual Sciences
      Madison, MS, United States
  • 2010
    • Odense University Hospital
      • Department of Ophthalmology - E
      Odense, South Denmark, Denmark
    • University of Minnesota Twin Cities
      • Division of Epidemiology and Community Health
      Minneapolis, MN, United States
    • Royal Melbourne Hospital
      Melbourne, Victoria, Australia
    • Erasmus MC
      • Department of Epidemiology
      Rotterdam, South Holland, Netherlands
    • University of Michigan
      • Department of Biostatistics
      Ann Arbor, MI, United States
    • Queen's University Belfast
      • Centre for Vision and Vascular Science
      Belfast, NIR, United Kingdom
    • Singapore Institute for Clinical Sciences
      Tumasik, Singapore
  • 2009–2010
    • University of New South Wales
      • Faculty of Medicine
      Kensington, New South Wales, Australia
    • Baker IDI Heart and Diabetes Institute
      Melbourne, Victoria, Australia
    • Tan Tock Seng Hospital
      Tumasik, Singapore
    • Gloucestershire Hospitals NHS Foundation Trust
      Gloucester, England, United Kingdom
    • Sydney Hospital & Sydney Eye Hospital
      Sydney, New South Wales, Australia
    • Princess Alexandra Hospital (Queensland Health)
      • Division of Medicine
      Brisbane, Queensland, Australia
  • 2007–2010
    • Victoria University Melbourne
      Melbourne, Victoria, Australia
  • 2006–2009
    • Imperial College London
      • Faculty of Medicine
      London, ENG, United Kingdom