A site to transform Pubmed publications into these bibliographic reference formats: ADS, BibTeX, EndNote, ISI used by the Web of Knowledge, RIS, MEDLINE, Microsoft's Word 2007 XML.

Tien Y Wong - Top 30 Publications

Inter-relationship between ocular perfusion pressure, blood pressure, intraocular pressure profiles and primary open-angle glaucoma: the Singapore Epidemiology of Eye Diseases study.

To elucidate the inter-relationship between ocular perfusion pressure (OPP), blood pressure (BP), intraocular pressure (IOP) profiles and primary open-angle glaucoma (POAG) in a multiethnic Asian population.

Share Cared for Stable Glaucoma Patients: Economic Benefits and Patient-centered Outcomes of a Feasibility Trial.

To assess the quality of care and economic benefits of a shared care model managing patients with stable glaucoma in a primary eye care clinic (PEC) compared with a tertiary specialist outpatient clinic (SOC) in Singapore.

Diabetic Retinopathy and Macular Edema Quality-of-Life Item Banks: Development and Initial Evaluation Using Computerized Adaptive Testing.

The purpose of this study was to assess the psychometric properties of diabetic retinopathy (DR) and diabetic macular edema (DME) quality-of-life (QoL) item banks and determine the utility of the final calibrated item banks by simulating a computerized adaptive testing (CAT) application.

Ethnic Differences in the Prevalence and Risk Factors of Diabetic Retinopathy: The Singapore Epidemiology of Eye Diseases Study.

To evaluate the prevalence and risk factors for diabetic retinopathy (DR) in the Singapore Epidemiology of Eye Diseases (SEED) Study.

Dynamic changes in retinal vessel diameter during acute hyperglycemia in type 1 diabetes.

To investigate changes in retinal vessel diameter during acute hyperglycemia in patients with type 1 diabetes.

Using Retinal Imaging to Study Dementia.

The retina offers a unique "window" to study pathophysiological processes of dementia in the brain, as it is an extension of the central nervous system (CNS) and shares prominent similarities with the brain in terms of embryological origin, anatomical features and physiological properties.  The vascular and neuronal structure in the retina can now be visualized easily and non-invasively using retinal imaging techniques, including fundus photography and optical coherence tomography (OCT), and quantified semi-automatically using computer-assisted analysis programs. Studying the associations between vascular and neuronal changes in the retina and dementia could improve our understanding of dementia and, potentially, aid in diagnosis and risk assessment.  This protocol aims to describe a method of quantifying and analyzing retinal vasculature and neuronal structure, which are potentially associated with dementia. This protocol also provides examples of retinal changes in subjects with dementia, and discusses technical issues and current limitations of retinal imaging.

Macro- and Microvascular Parameters Following Toxic Shock Syndrome.

Whether individuals who had toxic shock syndrome (TSS) in childhood have differences in macro- and retinal microvascular parameters indicative of increased cardiovascular risk is unknown. We found no evidence of adverse macrovascular changes in 22 TSS participants compared to 60 control participants. Microvascular comparisons showed a reduction in retinal total fractal dimension which has been associated with cardiovascular risk factors in children.

The Study of Neurocognitive Outcomes, Radiological and Retinal Effects of Aspirin in Sleep Apnoea- rationale and methodology of the SNORE-ASA study.

Sleep disordered breathing (SDB) is highly prevalent in older adults. Increasing evidence links SDB to the risk of dementia, mediated via a number of pathways, some of which may be attenuated by low-dose aspirin. This study will evaluate, in a healthy older cohort, the prospective relationship between SDB and cognitive function, changes in retinal and cerebral microvasculature, and determine whether low-dose aspirin ameliorates the effects of SDB on these outcomes over 3years.

Global causes of blindness and distance vision impairment 1990-2020: a systematic review and meta-analysis.

Contemporary data for causes of vision impairment and blindness form an important basis of recommendations in public health policies. Refreshment of the Global Vision Database with recently published data sources permitted modelling of cause of vision loss data from 1990 to 2015, further disaggregation by cause, and forecasts to 2020.

Erratum to: Innovative technology shows impact of glycaemic control on peripheral retinal vessels in adolescents with type 1 diabetes.

Efficacy and Safety of Ranibizumab With or Without Verteporfin Photodynamic Therapy for Polypoidal Choroidal Vasculopathy: A Randomized Clinical Trial.

Polypoidal choroidal vasculopathy (PCV) is a common subtype of exudative age-related macular degeneration among Asian individuals. To our knowledge, there are no large randomized clinical trials to evaluate intravitreal ranibizumab, with and without verteporfin photodynamic therapy (vPDT), for the treatment of PCV.

Metabolomics of Diabetic Retinopathy.

Metabolomics is the study of dysregulated metabolites in biological materials. We reviewed the use of the technique to elucidate the genetic and environmental factors that contribute to the development of diabetic retinopathy.

Inter-relationship between visual symptoms, activity limitation and psychological functioning in patients with diabetic retinopathy.

We explored the direct and indirect impact of restrictions in daily living activities on the relationship between perceived visual symptoms associated with diabetic retinopathy (DR) and psychological functioning.

Magnitude, temporal trends, and projections of the global prevalence of blindness and distance and near vision impairment: a systematic review and meta-analysis.

Global and regional prevalence estimates for blindness and vision impairment are important for the development of public health policies. We aimed to provide global estimates, trends, and projections of global blindness and vision impairment.

Innovative technology shows impact of glycaemic control on peripheral retinal vessels in adolescents with type 1 diabetes.

Retinal imaging enables non-invasive microvasculature assessment; however, only central retinal vessels have been studied in type 1 diabetes. Peripheral smaller vessels have a major haemodynamic role and may differ from central vessels in their response to the diabetic milieu. We hypothesise that diabetes has a greater impact on peripheral retinal vessels vs central vessels.

Frequency of Evidence-Based Screening for Diabetic Retinopathy.

Combined poor diabetes control indicators are associated with higher risks of diabetic retinopathy and macular edema than poor glycemic control alone.

To examine the association of individual and combined indicators of diabetes control with diabetic retinopathy and diabetic macular edema.

Change in vision-related quality of life and influencing factors in Asians receiving treatment for neovascular age-related macular degeneration.

To assess the change in vision-related quality of life (VRQoL) after treatment for neovascular age-related macular degeneration (nAMD) and factors influencing this change in an Asian population.

Determinants of Quantitative Optical Coherence Tomography Angiography Metrics in Patients with Diabetes.

Early microvascular damage in diabetes (e.g. capillary nonperfusion and ischemia) can now be assessed and quantified with optical coherence tomography-angiography (OCT-A). The morphology of vascular tissue is indeed affected by different factors; however, there is a paucity of data examining whether OCT-A metrics are influenced by ocular, systemic and demographic variables in subjects with diabetes. We conducted an observational cross-sectional study and included 434 eyes from 286 patients with diabetes. Foveal avascular zone (FAZ) area, FAZ circularity, total and parafoveal vessel density (VD), fractal dimension (FD), and vessel diameter index (VDI) from the superficial capillary plexus OCT-angiogram were measured by a customized automated image analysis program. We found that diabetic retinopathy (DR) severity was associated with increased FAZ area, decreased FAZ circularity, lower VD, lower FD, and increased VDI. Enlarged FAZ area was correlated with shorter axial length and thinner central subfield macular thickness. Decreased FAZ circularity was correlated with a reduction in visual function. Decreased VD was correlated with thinner macular ganglion-cell inner plexiform layer. Increased VDI was correlated with higher fasting glucose level. We concluded that the effects of ocular and systemic factors in diabetics should be taken into consideration when assessing microvascular alterations via OCT-A.

Diabetic macular oedema: evidence-based treatment recommendations for Asian countries.

Diabetic macular oedema is the most common cause of diabetic retinopathy-induced vision loss. Efficacy of anti-vascular endothelial growth factor therapy in diabetic macular oedema has been demonstrated in randomized controlled trials. An Asian-specific guideline for diabetic macular oedema treatment is needed as patients in Asia tend to present with far more advanced disease than seen elsewhere in the world. Previous reviews of diabetic macular oedema management lacked a broader assessment of anti-vascular endothelial growth factor treatment choices and newer trials. Recent clinical trial data allow head-to-head comparisons between the different anti-vascular endothelial growth factor agents and treatment regimens. This review aims to summarize the clinical evidence related to various treatment regimens for clinicians, with a focus on anti-vascular endothelial growth factor therapies, and to provide guidance on the treatment of diabetic macular oedema in Asian patients.

Urinary Isoprostane Levels and Age-Related Macular Degeneration.

Oxidative stress, characterized by an excessive production of reactive oxygen intermediates has been suggested to play a role in the pathogenesis of age-related macular degeneration (AMD). We examined the association of urinary F2-isoprostanes (F2-IsoPs), a marker of lipid peroxidation and the most reliable marker of oxidative damage with AMD.

Progressive Retinal Vasodilation in Patients With Type 1 Diabetes: A Longitudinal Study of Retinal Vascular Geometry.

Retinal vessels can be used to noninvasively monitor changes in microvasculature. These changes in retinal vascular geometry (RVG) may predict chronic diabetes complications. We evaluated longitudinal RVG changes in adolescents with type 1 diabetes.

Ethnic Differences in the Association Between Age-Related Macular Degeneration and Vision-Specific Functioning.

Understanding the link between ethnicity and health is critical to making appropriate public policy decisions. Few population-level data are available about this connection, however, including the influence of ethnicity on the association between age-related macular degeneration (AMD) and vision-specific functioning (VSF).

A nationwide cohort study of cigarette smoking and risk of neovascular age-related macular degeneration in East Asian men.

Few longitudinal studies have evaluated the relationship between cigarette smoking and risk of neovascular age-related macular degeneration (AMD) among Asian populations. This study aimed to prospectively evaluate the association between cigarette smoking and risk of neovascular AMD among Korean men.

Classification of SD-OCT volumes with multi pyramids, LBP and HOG descriptors: application to DME detections.

This paper deals with the automated detection of Diabetic Macular Edema (DME) on Optical Coherence Tomography (OCT) volumes. Our method considers a generic classification pipeline with preprocessing for noise removal and flattening of each B-Scan. Features such as Histogram of Oriented Gradients (HOG) and Local Binary Patterns (LBP) are extracted and combined to create a set of different feature vectors which are fed to a linear-Support Vector Machines (SVM) Classifier. Experimental results show a promising sensitivity/specificity of 0.75/0.87 on a challenging dataset.


An anomaly detection approach for the identification of DME patients using spectral domain optical coherence tomography images.

This paper proposes a method for automatic classification of spectral domain OCT data for the identification of patients with retinal diseases such as Diabetic Macular Edema (DME). We address this issue as an anomaly detection problem and propose a method that not only allows the classification of the OCT volume, but also allows the identification of the individual diseased B-scans inside the volume. Our approach is based on modeling the appearance of normal OCT images with a Gaussian Mixture Model (GMM) and detecting abnormal OCT images as outliers. The classification of an OCT volume is based on the number of detected outliers. Experimental results with two different datasets show that the proposed method achieves a sensitivity and a specificity of 80% and 93% on the first dataset, and 100% and 80% on the second one. Moreover, the experiments show that the proposed method achieves better classification performance than other recently published works.

Novel genetic loci associated with hippocampal volume.

The hippocampal formation is a brain structure integrally involved in episodic memory, spatial navigation, cognition and stress responsiveness. Structural abnormalities in hippocampal volume and shape are found in several common neuropsychiatric disorders. To identify the genetic underpinnings of hippocampal structure here we perform a genome-wide association study (GWAS) of 33,536 individuals and discover six independent loci significantly associated with hippocampal volume, four of them novel. Of the novel loci, three lie within genes (ASTN2, DPP4 and MAST4) and one is found 200 kb upstream of SHH. A hippocampal subfield analysis shows that a locus within the MSRB3 gene shows evidence of a localized effect along the dentate gyrus, subiculum, CA1 and fissure. Further, we show that genetic variants associated with decreased hippocampal volume are also associated with increased risk for Alzheimer's disease (rg=-0.155). Our findings suggest novel biological pathways through which human genetic variation influences hippocampal volume and risk for neuropsychiatric illness.

Evidence of Microvascular Changes in the Retina following Kawasaki Disease.

It is unclear whether all children with Kawasaki disease (KD) have increased later cardiovascular risk. The retinal microvasculature reflects changes in the microcirculation and is associated with traditional cardiovascular risk factors and events. The aim of this study was to investigate retinal microvascular parameters in two populations of patients with previous KD and control participants. We performed case-control studies of 116 (57 patients and 59 control participants) Australian and 156 (78 patients and 78 control participants) Singaporean individuals, at least two years since their acute illness. Standardised retinal photographs were graded by trained technicians using a semi-automated software, which quantifies the retinal microvasculature (calibre, branching angle, fractal dimensions, and tortuosity). Retinal venules of Singaporean KD patients were 9.67 μm (95% CI 4.87 to 14.51, p < 0.001) larger than control participants following correction for traditional cardiovascular risk factors. An incremental increase in the size of retinal venules in those with coronary artery abnormalities was observed. There was limited evidence that retinal venules were larger in Australian KD patients with coronary artery abnormalities compared to control participants (7.34 μm, 95% CI 1.30 to 15.99, p = 0.10). Differences in retinal microvasculature were particularly evident in Singaporean KD patients. Larger retinal venules may reflect chronic inflammation and endothelial dysfunction, and are associated with coronary artery disease in adults.

Rationale and Methodology for a Community-Based Study of Diabetic Retinopathy in an Indonesian Population with Type 2 Diabetes Mellitus: The Jogjakarta Eye Diabetic Study in the Community.

There are no available data about diabetic retinopathy (DR) in the Indonesian population. This report summarizes the rationale and study design of the Jogjakarta Eye Diabetic Study in the Community (JOGED.COM), a community-based study to estimate the prevalence and risk factors of DR in persons with type 2 diabetes in Jogjakarta, Indonesia.