To describe detailed morphologic and vascular features of the choroid in eyes with high myopia.
Cross-sectional study.
A total of 515 eyes of young men (mean age 21.59 ± 1.15 years) with high myopia ...(defined as −6.0 diopter D or worse, mean spherical equivalent −8.66 ± 2.00 D) and 88 controls with emmetropia in both eyes underwent choroidal imaging using spectral-domain optical coherence tomography with enhanced depth imaging (EDI-OCT). Raw OCT images were loaded on a custom-written application on MATLAB that enabled delineation for detailed morphologic and vascular analyses, including the distance of thickest point from the foveal center, choroidal thickness, choroidal volume, choroidal vascular and stromal areas within the macular (6 mm) and foveal (1.5 mm) regions, and choroidal vascularity, which was determined by dividing vascular area by total choroidal area.
The choroid in high myopic eyes was thickest temporally compared to subfoveal location in emmetropic subjects (thickest point distance from fovea: −1.51 ± 1.42 mm vs −0.53 ± 1.06 mm, P < .001). In eyes with high myopia, after adjusting for age, choroidal vascular and stromal areas were significantly lower (vascular area: β = −0.306, stromal area: β = −0.377, both P < .001) than control eyes with emmetropia at the macular region. Compared to control eyes with emmetropia, choroidal vascularity was greater in eyes with high myopia (β = 0.032, P < .001). Similar results were observed for the subfoveal region.
Our study suggests that choroidal thinning in eyes with high myopia is associated with the reduction in both its stromal and vascular components.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
To examine early myopia-related optic disc and retinal changes in a Singapore Chinese adolescent sample without confounding ocular or systemic disease.
Population-based cross-sectional study.
...Children aged 12 to 16 years at a follow-up visit for Singapore Cohort Study of Risk Factors for Myopia.
Detailed eye examinations, including cycloplegic autorefraction and contact biometry, were performed. Retinal photographs were acquired using nonmydriatic retinal photography among children who attended follow-up examinations in 2006, and were graded for myopia-related optic disc signs and macular changes by a single experienced grader. Optic nerve head parameters were measured adjusting for camera and ocular magnification with appropriate formulae.
Optic disc changes (tilt, beta peripapillary atrophy β-PPA, and optic nerve parameters) and macular changes (staphyloma, lacquer cracks, Fuchs' spot, and chorioretinal atrophy).
Retinal photography data were available for 1227 children (median age, 14 years; range 12-16). Tilted optic discs were found in 454 subjects (37%), and were associated with myopic spherical equivalent refractions (-3.6 diopters D vs -1.3 D; P<0.0001), higher cylindrical error (0.9 vs 0.7 D; P = 0.0001) and longer axial length (24.93 vs 23.96 mm; P<0.0001). The pattern of distribution of the axes of the tilted discs and corneal curvature were similar (P = 0.4). All linear optic nerve parameters, except vertical disc diameter (P = 0.15), were significantly smaller in eyes with than without tilted discs (P <0.001) after adjusting for confounders. Apart from 20 cases, all eyes with tilted optic discs had associated β-PPA. We identified only 1 case each (0.1% prevalence) of staphyloma and lacquer cracks in this sample.
In this Asian adolescent population, tilted optic discs were highly prevalent, in contrast with the lower prevalence reported in Caucasian populations. Eyes with tilted discs tended to have smaller optic cups with smaller cup-to-disc ratios, and were associated with myopic refraction, higher astigmatism, and longer axial length. There were similar patterns of distribution between the axis of disc tilt and the axis of corneal curvature, which could have embryologic origins. In contrast with optic disc changes, myopic macular changes were rare in this age group, suggesting that these changes may develop later in life.
The authors have no proprietary or commercial interest in any of the materials discussed in this article.
Clinicians and researchers have traditionally worked in independent silos, with limited collaboration to rapidly translate discovery into clinical practice. At institutional level, hospitals and ...universities have also tended to work independently with limited success in leveraging each other's strengths with a view to improving population health. The consequences include fragmentation of clinical services, poor communication between researchers and clinicians, lengthy delays in identification of clinical problems requiring innovative solutions through research and a generation of clinicians who are not well equipped with all the skills to address future health needs. Academic Health Science Systems (AHSS) have been proposed as a mechanism for driving effective collaboration between academia and clinical services. There are examples of well established AHSS and the benefits have been articulated. In Singapore, three AHSS have been established over the past 15 years. National dental specialty centres and one dental school have been embedded in AHSS and have well established multi‐disciplinary collaboration across clinical and academic domains. The aim of this commentary is to describe the concept of an AHSS and some of the areas where dentistry in Singapore has been transformed by having key dental institutions embedded in an AHSS.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Purpose
To examine the association between near work, screen time including TV and outdoor time with myopia in children from the Sunflower Myopia Asian Eye Epidemiology Consortium (AEEC).
Methods
We ...analysed AEEC cross‐sectional data (12 241 children) on risk factors (near work, screen time including TV and outdoor time) and myopia of six population‐based studies (China, Hong Kong and Singapore). Cycloplegic refraction and axial length (AL) measurements were included. Risk factors were determined using questionnaires. Data were pooled from each study, and multivariable regression analysis was performed to evaluate the associations between risks factors and myopia, spherical equivalent (SE) and AL.
Results
Among the included children, 52.1% were boys, 98.1% were Chinese and 69.7% lived in urban areas. Mean±standard deviation (SD) for age was 8.8 ± 2.9 years, for SE was −0.14 ± 1.8 D and for AL was 23.3 ± 1.1 mm. Myopia prevalence was 30.6%. In multivariate analysis, more reading and writing (OR = 1.17; 95% CI, 1.11–1.24), more total near work (OR = 1.05; 95% CI, 1.02–1.09) and less outdoor time (OR = 0.82, 95% CI, 0.75–0.88) were associated with myopia (p’s < 0.05). These factors were similarly associated with SE and AL (p’s < 0.05), except for total near work and AL (p = 0.15). Screen time including TV was not significantly associated with myopia (p = 0.49), SE (p = 0.49) or AL (p = 0.83).
Conclusion
In this study, increased reading and writing and decreased outdoor time were associated with myopia. Screen time may be a surrogate factor of near work or outdoor time, but further research is needed to assess its role as an independent risk factor for myopia.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Objective
To determine the longitudinal associations between retinal vascular profile (RVP) and four major cardiometabolic diseases; and to quantify the predictive improvements when adding RVP beyond ...traditional risk factors in individuals with diabetes.
Methods
Subjects were enrolled from the Singapore Epidemiology of Eye Disease (SEED) study, a multi‐ethnic population‐based cohort. Four incident cardiometabolic diseases, calculated over a ~ 6‐year period, were considered: cardiovascular disease (CVD), hypertension (HTN), diabetic kidney disease (DKD), and hyperlipidemia (HLD). The RVP—vessel tortuosity, branching angle, branching coefficient, fractal dimension, vessel caliber, and DR status—was characterized at baseline using a computer‐assisted program. Traditional risk factors at baseline included age, gender, ethnicity, smoking, blood pressure (BP), HbA1c, estimated glomerular filtration rate (eGFR), or cholesterol. The improvements in predictive performance when adding RVP (compared with only traditional risk factors) was calculated using several metrics including area under the receiver operating characteristics curve (AUC) and net reclassification improvement (NRI).
Results
Among 1770 individuals with diabetes, incidences were 6.3% (n = 79/1259) for CVD, 48.7% (n = 166/341) for HTN, 14.6% (n = 175/1199) for DKD, and 59.4% (n = 336/566) for HLD. DR preceded the onset of CVD (RR 1.851.14;3.00) and DKD (1.44 1.06;1.96). Narrower arteriolar caliber preceding the onset of HTN (0.84 0.72;0.99), and changes in arteriolar branching angle preceded the onset of CVD (0.78 0.62;0.98) and HTN (1.15 1.03;1.29). The largest predictive improvement was found for HTN with AUC increment of 3.4% (p = .027) and better reclassification of 11.4% of the cases and 4.6% of the controls (p = .008).
Conclusion
We found that RVPs improved the prediction of HTN in individuals with diabetes, but add limited information for CVD, DKD, and HLD predictions.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Diabetic retinopathy (DR) is a leading cause of visual impairment and blindness worldwide. Since DR was first recognized as an important complication of diabetes, there have been many attempts to ...accurately classify the severity and stages of disease. These historical classification systems evolved as understanding of disease pathophysiology improved, methods of imaging and assessing DR changed, and effective treatments were developed. Current DR classification systems are effective, and have been the basis of major research trials and clinical management guidelines for decades. However, with further new developments such as recognition of diabetic retinal neurodegeneration, new imaging platforms such as optical coherence tomography and ultra wide-field retinal imaging, artificial intelligence and new treatments, our current classification systems have significant limitations that need to be addressed. In this paper, we provide a historical review of different classification systems for DR, and discuss the limitations of our current classification systems in the context of new developments. We also review the implications of new developments in the field, to see how they might feature in a future, updated classification.
Fractal analysis is a method of quantifying the branching complexity and density of the retinal vessels. We hypothesized that reduced fractal dimension, signifying a sparser vascular network, is ...associated with long-term stroke mortality.
We examined the relationship of fractal dimension and stroke mortality in a prospective, population-based cohort of 3143 participants aged 49 years or older. Fractal dimension was measured from digitized fundus photographs using a computer-automated method. Stroke mortality was documented from Australian National Death Index records. We defined reduced fractal dimension as values in the lowest quartile.
Over 12 years, there were 132 (4.2%) stroke-related deaths. Stroke-related mortality was higher in participants with reduced fractal dimension (lowest quartile) compared with the highest quartile (7.7% versus 1.3%,
<0.01). After controlling for age, gender, smoking, blood pressure, history of stroke, and other factors, participants with reduced fractal dimension had higher stroke mortality (hazard ratio, 2.42 95% CI, 1.15-5.07, lowest versus highest quartile). When modeled as a continuous variable, reduced fractal dimension was associated with increased stroke mortality (multivariable-adjusted hazard ratio, 1.26 95% CI, 1.06-1.51, per SD decrease).
Reduced retinal vascular fractal dimension is independently associated with 12-year stroke mortality. Reduced fractal dimension may indicate cerebral tissue hypoxia and increased risk of stroke.
The clinical signs include generalized and focal arteriolar narrowing, arterio-venous nicking, increased retinal arteriolar light reflex (copper or silver wiring), flameand blot-shaped retinal ...hemorrhages, cotton wool spots, and, in severe cases, optic disc swelling (8,9). ... it is unknown whether modification of risk factors (e.g., increased physical activity, reduction in weight) or institution of treatment (e.g., diabetes and antihypertensive medications) may improve retinal vascular measures and whether this is associated with lowered risks of diabetes, hypertension, and their complications.
Myopia is a major public health problem, particularly in East Asia. In this summary report, we present key findings and recommendations on strategies for myopia control discussed during the meeting ...jointly organised by the WHO Regional Office for the Western Pacific, the International Agency for the Prevention of Blindness and the Brien Holden Vision Institute. First, myopia prevalence was reported to be increasing, with up to 80% of junior school students with myopia in East Asia. However, common challenges in implementing myopia control strategies on a national level included lack of school screening programme, and paucity of accurate prevalence data. Second, there continues to be broad public misconception about myopia and myopia control, including lack of parental awareness and resistance to wearing spectacles. Third, best practices for myopia management were shared, and recommendations for policy implementation are presented in this review. Key recommendations from this meeting include increased public education to raise parent and teacher awareness; encouragement of increased outdoor time of 2-3 hours per day for schoolchildren-as a practical public health intervention that has been shown to potentially reduce onset and progression of myopia. Governments and non-governmental organisations are encouraged to collaborate, especially education and health ministries to develop national myopia prevention programme. Lastly, it is important to emphasise that the key recommendations, such as increasing outdoor time for schoolchildren, are specific for East Asian nations in the Western Pacific region and may not be entirely applicable for Western nations.
IntroductionHigh myopia is a pressing public health concern due to its increasing prevalence, younger trend and the high risk of blindness, particularly in East Asian countries, including China. The ...China Alliance of Research in High Myopia (CHARM) is a newly established consortium that includes more than 100 hospitals and institutions participating across the nation, aiming to promote collaboration and data sharing in the field of high myopia screening, classification, diagnosis and therapeutic development.Methods and analysisThe CHARM project is an ongoing study, and its initiation is distinguished by its unprecedented scale, encompassing plans to involve over 100 000 Chinese patients. This initiative stands out not only for its extensive scope but also for its innovative application of artificial intelligence (AI) to assist in diagnosis and treatment decisions. The CHARM project has been carried out using a ‘three-step’ strategy. The first step involves the collection of basic information, refraction, axial length and fundus photographs from participants with high myopia. In the second step, we will collect multimodal imaging data to expand the scope of clinical information, for example, optical coherence tomography and ultra-widefield fundus images. In the final step, genetic testing will be conducted by incorporating patient family histories and blood samples. The majority of data collected by CHARM is in the form of images that will be used to detect and predict the progression of high myopia through the identification and quantification of biomarkers such as fundus tessellation, optic nerve head and vascular parameters.Ethics and disseminationThe study has received approval from the Ethics Committee of Beijing Tongren Hospital (TREC2022-KY045). The establishment of CHARM represents an opportunity to create a collaborative platform for myopia experts and facilitate the dissemination of research findings to the global community through peer-reviewed publications and conference presentations. These insights can inform clinical decision-making and contribute to the development of new treatment modalities that may benefit patients worldwide.Trial registration numberChiCTR2300071219.
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