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Aims/hypothesis The aim of the study was to examine the association of retinal vessel morphometry with BP, body composition and biochemistry, and to determine whether these associations differ by diabetes status. Methods The UK Biobank ocular assessment included 68,550 participants aged 40-70 years who underwent non-mydriatic retinal photography, BP and body composition measurements, and haematological analysis. A fully automated image analysis program provided measurements of retinal vessel diameter and tortuosity. The associations between retinal vessel morphology and cardiometabolic risk factors by diabetes status were examined using multilevel linear regression, to provide absolute differences in vessel diameter and percentage differences in tortuosity (allowing for within-person clustering). Results A total of 50,233 participants (a reduction from 68,550) were included in these analyses. Overall, those with diabetes had significantly more tortuous venules and wider arteriolar diameters compared with those without. Associations between venular tortuosity and cardiometabolic risk factors differed according to diabetes status (p interaction 1c, C-reactive protein, white cell count and granulocyte count. For example, a unit rise in white cell count was associated with a 0.18% increase (95% CI 0.05, 0.32%) in venular tortuosity for those without diabetes and a 1.48% increase (95% CI 0.90, 2.07%) among those with diabetes. For arteriolar diameter, significant interactions were evident for systolic BP, diastolic BP, mean arterial pressure (MAP) and LDL-cholesterol. For example, a 10 mmHg rise in systolic BP was associated with a −0.92 μm difference (95% CI −0.96 to −0.88 μm) in arteriolar diameter for those without diabetes, and a −0.58 μm difference (95% CI −0.76 to −0.41 μm) among those with diabetes. No interactions were observed for arteriolar tortuosity or venular diameters. Conclusions/interpretation We provide clear evidence of the modifying effect of diabetes on cardiometabolic risk factor associations with retinal microvascular architecture. These observations suggest the occurrence of preclinical disease processes, and may be a sign of impaired autoregulation due to hyperglycaemia, which has been suggested to play a pivotal role in the development of diabetes-related microvascular complications. Data Availability The data supporting the results reported here are available through the UK Biobank (https://www.ukbiobank.ac.uk/enable-your-research/apply-for-access). Graphical abstract

We report the sensitivity and specificity of van Herick (VH) grading in detecting gonioscopically-defined primary angle closure suspects (PACS) among subjects screened for participation in a population-based trial in southern China. A cut-off of VH≤25% was found to have sensitivity and specificity rates of 98.2% and 25.9%, respectively. Rates were adjusted for missing gonioscopy data, resulting in a sensitivity and specificity of 92.5% and 61.5%, respectively.

To examine the association of alcohol consumption and type of alcoholic beverage with incident cataract surgery in 2 large cohorts.Longitudinal, observational study.We included 469 387 participants of UK Biobank with a mean age of 56 years and 23 162 participants of European Prospective Investigation of Cancer (EPIC)-Norfolk with a mean age of 59 years.Self-reported alcohol consumption at baseline was ascertained by a touchscreen questionnaire in UK Biobank and a food-frequency questionnaire in EPIC-Norfolk. Cases were defined as participants undergoing cataract surgery in either eye as ascertained via data linkage to National Health Service procedure statistics. We excluded participants with cataract surgery up to 1 year after the baseline assessment visit or those with self-reported cataract at baseline. Cox proportional hazards models were used to examine the associations of alcohol consumption with incident cataract surgery, adjusted for age, sex, ethnicity, Townsend deprivation index, body mass index (BMI), smoking, and diabetes status.Incident cataract surgery.There were 19 011 (mean cohort follow-up of 95 months) and 4573 (mean cohort follow-up of 193 months) incident cases of cataract surgery in UK Biobank and EPIC-Norfolk, respectively. Compared with nondrinkers, drinkers were less likely to undergo cataract surgery in UK Biobank (hazard ratio [HR], 0.89; 95% confidence interval [CI], 0.85-0.93) and EPIC-Norfolk (HR, 0.90; 95% CI, 0.84-0.97) after adjusting for covariables. Among alcohol consumers, greater alcohol consumption was associated with a reduced risk of undergoing cataract surgery in EPIC-Norfolk (P0.001), whereas a U-shaped association was observed in the UK Biobank. Compared with nondrinkers, subgroup analysis by type of alcohol beverage showed the strongest protective association with wine consumption; the risk of incident cataract surgery was 23% and 14% lower among those in the highest category of wine consumption in EPIC-Norfolk and UK Biobank, respectively.Our findings suggest a lower risk of undergoing cataract surgery with low to moderate alcohol consumption. The association was particularly apparent with wine consumption. We cannot exclude the possibility of residual confounding, and further studies are required to determine whether this association is causal in nature.

Background/AimsThis work aimed to study the effect of long-term intraocular pressure (IOP) fluctuation on visual field (VF) progression 8 years post-trabeculectomy in Asian eyes.MethodsThis was a retrospective analysis of 8-year post-trabeculectomy data from The Singapore 5-Fluorouracil (5-FU) Study. VFs were analysed using Progressor software (Medisoft, Leeds, UK). Outcome measures included mean slope for VF per year, number of progressing points and mean slope for progressing points per year. Multivariate regression analyses were performed adjusting for age, gender, ethnicity, glaucoma type, intraoperative 5-FU, diabetes mellitus, hypertension, best pre-trabeculectomy VF mean deviation, post-trabeculectomy mean IOP, IOP reduction and IOP fluctuation (SD of IOPs at 6-monthly timepoints).Results127 (52.3%) subjects completed 8-year follow-up with ≥5 reliable VFs and ≥8 6-monthly IOP measurements. Mean age was 61.8±9.6 years. Post-operatively, mean IOP was 14.2±2.8 mm Hg and mean IOP fluctuation was 2.53±1.20 mm Hg. Higher IOP fluctuation was associated with greater mean slope for field (B=−0.071; p=0.013), number of progressing points (B=0.963; p=0.014) and VF progression as defined by ≥1 progressing point (OR=1.585; p=0.029). There was also a trend towards eyes with higher IOP fluctuation having ≥3 adjacent progressing points in the same hemifield (OR=1.489; p=0.055). Greater mean IOP reduction post-trabeculectomy was associated only with a lower mean slope for progressing points per year (B=−0.026; p=0.028). There was no significant effect of intra-operative 5-FU compared with placebo for all outcome measures.ConclusionIn post-trabeculectomy Asian eyes with well-controlled IOP, higher long-term IOP fluctuation may be associated with greater VF progression.

Purpose To describe and compare associations with macular retinal nerve fiber layer (mRNFL), ganglion cell complex (GCC), and ganglion cell–inner plexiform layer (GCIPL) thicknesses in a large cohort. Design Cross-sectional study. Participants We included 42 044 participants in the UK Biobank. The mean age was 56 years. Methods Spectral-domain OCT macular images were segmented and analyzed. Corneal-compensated intraocular pressure (IOPcc) was measured with the Ocular Response Analyzer (Reichert, Corp., Buffalo, NY). Multivariable linear regression was used to examine associations with mean mRNFL, GCC, and GCIPL thicknesses. Factors examined were age, sex, ethnicity, height, body mass index (BMI), smoking status, alcohol intake, Townsend deprivation index, education level, diabetes status, spherical equivalent, and IOPcc. Main Outcome Measures Thicknesses of mRNFL, GCC, and GCIPL. Results We identified several novel independent associations with thinner inner retinal thickness. Thinner inner retina was associated with alcohol intake (most significant for GCIPL: –0.46 μm for daily or almost daily intake compared with special occasion only or never [95% confidence interval (CI), 0.61–0.30]; P = 1.1×10–8), greater social deprivation (most significant for GCIPL: –0.28 μm for most deprived quartile compared with least deprived quartile [95% CI, –0.42 to –0.14]; P = 6.6×10–5), lower educational attainment (most significant for mRNFL: –0.36 μm for less than O level compared with degree level [95% CI, –0.45 to 0.26]; P = 2.3×10–14), and nonwhite ethnicity (most significant for mRNFL comparing blacks with whites: –1.65 μm [95% CI, –1.86 to –1.43]; P = 2.4×10–50). Corneal-compensated intraocular pressure was associated most significantly with GCIPL (–0.04 μm/mmHg [95% CI, –0.05 to –0.03]; P = 4.0×10–10) and was not associated significantly with mRNFL (0.00 μm/mmHg [95% CI, –0.01 to 0.01]; P = 0.77). The variables examined explained a greater proportion of the variance of GCIPL (11%) than GCC (6%) or mRNFL (7%). Conclusions The novel associations we identified may be important to consider when using inner retinal parameters as a diagnostic tool. Associations generally were strongest with GCIPL, particularly for IOP. This suggests that GCIPL may be the superior inner retinal biomarker for macular pathophysiologic processes and especially for glaucoma.

PURPOSE: Genetic and epidemiologic studies have shown that lipid genes and High Density Lipoproteins (HDL) are implicated in age-related macular degeneration (AMD). We studied circulating lipid levels in relation to AMD in a large European dataset, and investigated whether this relationship is driven by certain sub fractions. DESIGN: (Pooled) analysis of cross-sectional data. PARTICIPANTS: 30,953 individuals aged 50+ participating in the E3 consortium; and 1530 individuals from the Rotterdam Study with lipid sub fraction data. METHODS: In E3, AMD features were graded per eye on fundus photographs using the Rotterdam Classification. Routine blood lipid measurements were available from each participant. Data on genetics, medication and confounders such as body mass index, were obtained from a common database. In a subgroup of the Rotterdam Study, lipid sub fractions were identified by the Nightingale biomarker platform. Random-intercepts mixed-effects models incorporating confounders and study site as a random-effect were used to estimate the associations. MAIN OUTCOME MEASURES: early, late or any AMD, phenotypic features of early AMD, lipid measurements. RESULTS: HDL was associated with an increased risk of AMD, corrected for potential confounders (Odds Ratio (OR) 1.21 per 1mmol/L increase (95% confidence interval[CI] 1.14-1.29); while triglycerides were associated with a decreased risk (OR 0.94 per 1mmol/L increase [95%CI 0.91-0.97]). Both were associated with drusen size, higher HDL raises the odds of larger drusen while higher triglycerides decreases the odds. LDL-cholesterol only reached statistical significance in the association with early AMD (p=0.045). Regarding lipid sub fractions: the concentration of extra-large HDL particles showed the most prominent association with AMD (OR 1.24 [95%CI 1.10-1.40]). The CETP risk variant (rs17231506) for AMD was in line with increased-HDL levels (p=7.7x10-7); but LIPC risk variants (rs2043085, rs2070895) were associated in an opposite way (p=1.0x10-6 and 1.6x10-4). CONCLUSIONS: Our study suggests that HDL-cholesterol is associated with increased risk of AMD and triglycerides negatively associated. Both show the strongest association with early AMD and drusen. Extra-large HDL sub fractions seem to be drivers in the relation with AMD, variants in lipid genes play a more ambiguous role in this association. Whether systemic lipids directly influence AMD or represent lipid metabolism in the retina remains a question to be answered.

Purpose To examine associations between retinal vessel morphometry and cardiometabolic risk factors in older British men and women. Design Retinal imaging examination as part of the European Prospective Investigation into Cancer—Norfolk Eye Study. Participants Retinal imaging and clinical assessments were carried out in 7411 participants. Retinal images were analyzed using a fully automated validated computerized system that provides novel measures of vessel morphometry. Methods Associations between cardiometabolic risk factors, chronic disease, and retinal markers were analyzed using multilevel linear regression, adjusted for age, gender, and within-person clustering, to provide percentage differences in tortuosity and absolute differences in width. Main Outcomes Measures Retinal arteriolar and venular tortuosity and width. Results In all, 279 802 arterioles and 285 791 venules from 5947 participants (mean age, 67.6 years; standard deviation [SD], 7.6 years; 57% female) were analyzed. Increased venular tortuosity was associated with higher body mass index (BMI; 2.5%; 95% confidence interval [CI], 1.7%–3.3% per 5 kg/m 2 ), hemoglobin A1c (HbA1c) level (2.2%; 95% CI, 1.0%–3.5% per 1%), and prevalent type 2 diabetes (6.5%; 95% CI, 2.8%–10.4%); wider venules were associated with older age (2.6 μm; 95% CI, 2.2–2.9 μm per decade), higher triglyceride levels (0.6 μm; 95% CI, 0.3–0.9 μm per 1 mmol/l), BMI (0.7 μm; 95% CI, 0.4–1.0 per 5 kg/m 2 ), HbA1c level (0.4 μm; 95% CI, –0.1 to 0.9 per 1%), and being a current smoker (3.0 μm; 95% CI, 1.7–4.3 μm); smoking also was associated with wider arterioles (2.1 μm; 95% CI, 1.3–2.9 μm). Thinner venules were associated with high-density lipoprotein (HDL) (1.4 μm; 95% CI, 0.7–2.2 per 1 mmol/l). Arteriolar tortuosity increased with age (5.4%; 95% CI, 3.8%–7.1% per decade), higher systolic blood pressure (1.2%; 95% CI, 0.5%–1.9% per 10 mmHg), in females (3.8%; 95% CI, 1.4%–6.4%), and in those with prevalent stroke (8.3%; 95% CI, –0.6% to 18%); no association was observed with prevalent myocardial infarction. Narrower arterioles were associated with age (0.8 μm; 95% CI, 0.6–1.0 μm per decade), higher systolic blood pressure (0.5 μm; 95% CI, 0.4–0.6 μm per 10 mmHg), total cholesterol level (0.2 μm; 95% CI, 0.0–0.3 μm per 1 mmol/l), and HDL (1.2 μm; 95% CI, 0.7–1.6 μm per 1 mmol/l). Conclusions Metabolic risk factors showed a graded association with both tortuosity and width of retinal venules, even among people without clinical diabetes, whereas atherosclerotic risk factors correlated more closely with arteriolar width, even excluding those with hypertension and cardiovascular disease. These noninvasive microvasculature measures should be evaluated further as predictors of future cardiometabolic disease.

Item does not contain fulltext Primary open-angle glaucoma (POAG), the most common optic neuropathy, is a heritable disease. Siblings of POAG cases have a ten-fold increased risk of developing the disease. Intraocular pressure (IOP) and optic nerve head characteristics are used clinically to predict POAG risk. We conducted a genome-wide association meta-analysis of IOP and optic disc parameters and validated our findings in multiple sets of POAG cases and controls. Using imputation to the 1000 genomes (1000G) reference set, we identified 9 new genomic regions associated with vertical cup-disc ratio (VCDR) and 1 new region associated with IOP. Additionally, we found 5 novel loci for optic nerve cup area and 6 for disc area. Previously it was assumed that genetic variation influenced POAG either through IOP or via changes to the optic nerve head; here we present evidence that some genomic regions affect both IOP and the disc parameters. We characterized the effect of the novel loci through pathway analysis and found that pathways involved are not entirely distinct as assumed so far. Further, we identified a novel association between CDKN1A and POAG. Using a zebrafish model we show that six6b (associated with POAG and optic nerve head variation) alters the expression of cdkn1a. In summary, we have identified several novel genes influencing the major clinical risk predictors of POAG and showed that genetic variation in CDKN1A is important in POAG risk.

The development and implementation of innovation by health care providers is widely understood as a multi-determinant and multi-level process. Theories at different analytical levels (i.e. both micro and organisational) are needed in order to capture the processes that influence innovation by health care providers. This paper combines a micro theory of innovation, actor-network theory, with organisational level processes using the “resource based view of the firm”, to examine the influence of, and interplay between, innovation-seeking teams (micro) and underlying organisational capabilities (meso) during the development and implementation of service innovation. The study is based on two examples of service innovation in relation to ophthalmology services run by a specialist English NHS Trust at multiple locations in a large city. We conducted interviews (28) with stakeholders within and outside the Trust and non-participant observation (40.5 hours) of outpatient clinics and service and board level meetings. Operational Research techniques were used to map the care process in the clinics and establish the theoretical improvement possible through service redesign. In practice, innovation at the micro service level was constrained by the complexity of and strain on existing outpatient clinics. Deficiencies in organisational capabilities for supporting innovation were identified, including the nature of manager-clinician relations and organisation-wide resources. The study concludes that actor-network theory can be combined with the resource-based view to highlight the influence of organisational capabilities on the management of innovation. Equally, actor-network theory helps to address the lack of theory in the resource-based view on the micro practices of implementing change.

Myopia is one of the most prevalent disorders of the eye. Higher myopia is associated with comorbidities that increase risks of severe and irreversible loss of vision, such as retinal detachment, subretinal neovascularization, dense cataract, and glaucoma. In recent years, reports from population-based prevalence studies carried out in various geographical areas now give a clear picture of the current distribution of refractive error. The scarcity of data from well-designed longitudinal cohort studies is still yet to be addressed. These studies have confirmed the previous data indicating that prevalence of refractive error varies according to ethnicity and geographic regions, and also point to an increase in myopia prevalence over the past half-century. The problem is particularly pronounced in affluent, industrialised areas of East Asia. Environmental risk factors for myopia related to socioeconomic status and lifestyle have been identified. The past decade has seen a greater understanding of the molecular biological mechanisms that determine refractive error, giving further support to the belief that myopia is the result of a complex interaction between genetic predisposition and environmental exposures. This review summarizes data on the prevalence, incidence, progression, associations, risk factors, and impact from recent epidemiological studies on myopia.

Objective To report the 8-year outcomes of Asian subjects who underwent trabeculectomy augmented by intraoperative 5-fluorouracil (5-FU) or placebo. Design Retrospective review of a randomized controlled trial. Participants Subjects with primary open-angle or angle-closure glaucoma. Methods Study subjects were prospectively followed up for 3 years. After the last subject recruited had completed 8 years of follow-up, the charts of all subjects were reviewed to capture data from the year 3 visit onward. Kaplan–Meier survival function with Cox regression was performed to identify risk factors associated with trabeculectomy failure at 8 years. Main Outcome Measures The primary outcome was trabeculectomy failure defined as intraocular pressure (IOP) >21 or 17 and >14 mmHg. Secondary outcomes included IOP at 8 years and number of glaucoma medications. Complete success was defined using IOP end points ≤21, ≤17, or ≤14 mmHg at 8 years without medications. Results Of the 243 enrolled subjects, 170 (70.0%) completed 8 years follow-up, 86 in the 5-FU and 84 in the placebo group. There was no significant difference in failure rates at 8 years for the failure definitions of IOP >21 mmHg (11.6% of the 5-FU group vs. 16.7% of the placebo group; P = 1.00), IOP >17 mmHg (23.3% of the 5-FU group vs. 31% of the placebo group; P = 0.78), and IOP >14 mmHg (46.5% of the 5-FU group vs. 58.3% of the placebo group; P = 0.37). Mean IOP at 8 years was 13.7 mmHg in the 5-FU versus 14.4 mmHg in the placebo group ( P = 0.24). Mean number of medications was 0.65 drops in the 5-FU versus 0.93 drops in the placebo group ( P = 0.06). Complete success with IOP ≤21 mmHg at 8 years was achieved in 48 subjects (55.8%) in the 5-FU and 33 subjects (39.3%) in the placebo group ( P = 0.09). Absence of bleb microcysts at 1 year, preoperative IOP, and number of bleb needlings performed within the first year were significantly associated with failure. Conclusions There was no significant difference in IOP between the 5-FU and the placebo group at 8 years. Financial Disclosure(s) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Purpose Age-related macular degeneration (AMD) is a frequent, complex disorder in elderly of European ancestry. Risk profiles and treatment options have changed considerably over the years, which may have affected disease prevalence and outcome. We determined the prevalence of early and late AMD in Europe from 1990 to 2013 using the European Eye Epidemiology (E3) consortium, and made projections for the future. Design Meta-analysis of prevalence data. Participants A total of 42 080 individuals 40 years of age and older participating in 14 population-based cohorts from 10 countries in Europe. Methods AMD was diagnosed based on fundus photographs using the Rotterdam Classification. Prevalence of early and late AMD was calculated using random-effects meta-analysis stratified for age, birth cohort, gender, geographic region, and time period of the study. Best-corrected visual acuity (BCVA) was compared between late AMD subtypes; geographic atrophy (GA) and choroidal neovascularization (CNV). Main Outcome Measures Prevalence of early and late AMD, BCVA, and number of AMD cases. Results Prevalence of early AMD increased from 3.5% (95% confidence interval [CI] 2.1%–5.0%) in those aged 55–59 years to 17.6% (95% CI 13.6%–21.5%) in those aged ≥85 years; for late AMD these figures were 0.1% (95% CI 0.04%–0.3%) and 9.8% (95% CI 6.3%–13.3%), respectively. We observed a decreasing prevalence of late AMD after 2006, which became most prominent after age 70. Prevalences were similar for gender across all age groups except for late AMD in the oldest age category, and a trend was found showing a higher prevalence of CNV in Northern Europe. After 2006, fewer eyes and fewer ≥80-year-old subjects with CNV were visually impaired (P = 0.016). Projections of AMD showed an almost doubling of affected persons despite a decreasing prevalence. By 2040, the number of individuals in Europe with early AMD will range between 14.9 and 21.5 million, and for late AMD between 3.9 and 4.8 million. Conclusion We observed a decreasing prevalence of AMD and an improvement in visual acuity in CNV occuring over the past 2 decades in Europe. Healthier lifestyles and implementation of anti–vascular endothelial growth factor treatment are the most likely explanations. Nevertheless, the numbers of affected subjects will increase considerably in the next 2 decades. AMD continues to remain a significant public health problem among Europeans.

Purpose: To determine if topical beta-blocker use is associated with increased cardiovascular mortality, particularly among people with self-reported glaucoma. Methods: All participants who participated in the first health check (N = 25,639) of the European Prospective Investigation into Cancer (EPIC) Norfolk cohort (1993–2013) were included in this prospective cohort study, with a median follow-up of 17.0 years. We determined use of topical beta-blockers at baseline through a self-reported questionnaire and prescription check at the first clinical visit. Cardiovascular mortality was ascertained through data linkage with the Office for National Statistics mortality database. Hazard ratios (HRs) were estimated using multivariable Cox regression models. Meta-analysis of the present study’s results together with other identified literature was performed using a random effects model. Results: We did not find an association between the use of topical beta-blockers and cardiovascular mortality (HR 0.93, 95% confidence interval, CI, 0.67–1.30). In the 514 participants with self-reported glaucoma, no association was found between the use of topical beta-blockers and cardiovascular mortality (HR 0.89, 95% CI 0.56–1.40). In the primary meta-analysis of four publications, there was no evidence of an association between the use of topical beta-blockers and cardiovascular mortality (pooled HR estimate 1.10, 95% CI 0.84–1.36). Conclusion: Topical beta-blockers do not appear to be associated with excess cardiovascular mortality. This evidence does not indicate that a change in current practice is warranted, although clinicians should continue to assess individual patients and their cardiovascular risk prior to commencing topical beta-blockers.

To examine the clinical outcomes of cataract extraction in eyes with primary angle closure (PAC) and coexisting cataract.Retrospective study of surgical outcomes after phacoemulsification and intraocular lens implantation in 55 eyes of 39 patients with PAC or occludable angles and visually symptomatic cataract. Approximately, 61.8% of eyes had received a peripheral iridotomy and 65% had evidence of glaucomatous optic neuropathy (GON).At 7.2 months after cataract extraction, a statistically significant reduction in intraocular pressure (IOP) was observed in all eyes with PAC (median 3 mm Hg, P=0.0001). The reduction in IOP was significantly greater in eyes with a higher preoperative IOP (P=0.0001). On average, one less glaucoma medication was in use postoperatively (P=0.01). Eyes with180 degrees of peripheral anterior synechiae (PAS) preoperatively achieved a significantly greater reduction in IOP postoperatively compared with those with less PAS (7.5 vs. 4.4 mm Hg, P=0.03). The observed reduction in IOP in eyes with PAC and GON was significantly greater compared with those without GON (5.6 vs. 2.5 mm Hg, P=0.01). Visual acuity was significantly improved after cataract extraction by a mean of -0.23 LogMAR units (P=0.0001).Contrary to earlier expectations, the observed reduction in postoperative IOP in eyes with PAC was significantly greater in the presence of a higher preoperative IOP, a larger number of glaucoma medication, narrower iridotrabecular angle width, and greater extent of PAS formation and in eyes with evidence of GON. Lens extraction seems to have a beneficial effect on IOP control in PAC, and is especially efficacious in more advanced cases.

Background: To assess the accuracy of Haigis, Holladay 1, Hoffer Q and SRK/T formulae in eyes with axial length of

Aim To estimate the prevalence of primary angle closure glaucoma (PACG) in European derived populations. Method Systematic review and modelling of PACG prevalence data from population studies. PACG was defined according to the ISGEO definition requiring structural and/or functional evidence of glaucomatous optic neuropathy. Prevalence estimates were applied to the 2010 United Nations projected population figures to estimate case numbers. Results The prevalence of PACG in those 40 years or more is 0.4% (95% CI 0.3% to 0.5%). Age-specific prevalence values are 0.02% (CI 0.00 to 0.08) for those 40–49 years, 0.60% (0.27 to 1.00) for those 50–59 years, 0.20% (0.06 to 0.42) for those 60–69 years and 0.94% (0.63 to 1.35) for those 70 years and older. Three-quarters of all cases occur in female subjects (3.25 female to 1 male; CI 1.76 to 5.94). Conclusion This analysis provides a current evidence-based estimate of PACG prevalence in European derived populations and suggests there are 130 000 people in the UK, 1.60 million people in Europe and 581 000 people in the USA with PACG today. Accounting for ageing population structures, cases are predicted to increase by 19% in the UK, 9% in Europe and 18% in the USA within the next decade. PACG is more common than previously thought, and all primary glaucoma cases should be considered to be PACG until the anterior chamber angle is shown to be open on gonioscopy.

Primary angle-closure glaucoma (PACG) frequently leads to severe vision loss. Prevalence among older Asian populations is high and given global demographics, the number of persons with PACG will increase dramatically in the coming decades. Improvements in imaging of the anterior segment will help us to identify more of those with angle closure, and important clinical trials that are currently underway will provide important evidence to support screening and treatment approaches for PACG. In this manuscript, we intend to review the existing evidences, to introduce some important on-going studies on PACG and to share the experience and viewpoints of the authors.

To examine the relationship between education, other risk factors and incident primary angle closure glaucoma (PACG).Glaucoma was excluded in a group of 4597 Mongolian volunteers in 1999. After 6 years, 1892 traced participants had full ophthalmic examination, dilated disc photographs and agreed to complete a questionnaire on socio-economic status. PACG was diagnosed using both structural and functional evidence from objective grading of paired disc photographs, follow up visual fields and clinical examination. Ophthalmic examination included van Herick grading, Goldmann intraocular pressure (IOP), gonioscopy, lens opacity grading and dilated disc examination. Central anterior chamber depth, lens thickness and axial length were recorded using ultrasound A scan mounted on a slitlamp. Education level was assessed using national census categories.PACG was diagnosed in 29 participants (6 year incidence = 1.53%, 95% confidence interval (CI) = 1.03-2.19%). In univariate analysis, risk factors for incident PACG included presence of refractive error, narrow van Herick grading of ≤15%, narrower average Shaffer grading, higher IOP, larger cup disc ratio and lower levels of education. In multivariate analysis, adjusted for age, sex, Shaffer grading, refractive error and IOP, those with no formal education were approximately 7 times more likely to develop PACG compared to those with8 years of formal schooling (OR = 7.27, 95% CI = 2.73-19.38).People with lower levels of education have a higher risk of incident PACG, independent of age, sex, IOP and axial length.

Purpose To describe a series of patients who have sustained a retinal vein occlusion (RVO) and also have primary angle-closure (PAC). Methods We retrospectively ascertained demographic characteristics (age, sex, and ethnicity), presentation (history and examination findings), investigations undertaken, features of angle-closure or occludable angles (symptoms, method of diagnosis, and treatment), and outcome (intraocular pressure (IOP) and visual acuity). Results Nineteen subjects were included in the study, comprising 9 males and 10 females, with an average age of 69 years (range 44 to 86 y). The ethnicity of the group was diverse. The mode of presentation in 75% of patients was that RVO and PAC were diagnosed at the same clinical visit. In the remaining 25% of cases, the diagnosis of PAC was delayed and ranged from 4 months to 9 years after the RVO. Increased IOP on dilation was found to have raised the suspicion of PAC in some patients, either at the time of first presentation with RVO or at a later date during follow-up for the RVO, leading to gonioscopy and a diagnosis of PAC. In 1 patient, an observed asymmetrical cup-to-disc ratio led to gonioscopy and diagnosis of PAC. Fourteen patients sustained a central retinal vein occlusion (CRVO), 2 subjects sustained a hemicentral retinal vein occlusion (HRVO), and 3 patients had a branch retinal vein occlusion. In the vast majority of cases in this series (18/19), no additional systemic risk factors were identified during follow-up apart from those that were present before the RVO. The diagnosis of PAC was made in all patients on the basis of static and dynamic gonioscopy. None of these patients had experienced any symptoms of acute or intermittent IOP rises as a consequence of angle-closure. Fifteen patients were diagnosed with PAC glaucoma in 1 or both eyes. Sixteen subjects (84.0%) underwent peripheral laser iridotomies and 7 patients (37.0%) had lens extraction to improve angle configuration. Conclusion Our study supports the belief that angle-closure may be associated with retinal vein occlusions, and should be borne in mind and excluded when investigating the patient with RVO, especially CRVO/HRVO. We suggest that gonioscopy should be done in all patients presenting with RVO.

To summarize the design and methodology of a large-scale trial in southern China, the Zhongshan Angle Closure Prevention (ZAP) trial. This trial will determine if laser iridotomy (LI) is superior to no treatment for managing Chinese people who are Primary Angle Closure Suspects (PACS). In this trial, PACS was defined as having 6 or more clock hours of angle circumference in which the pigmented trabecular meshwork was not visible under static gonioscopy in both eyes without elevated intraocular pressure, peripheral anterior synechiae or glaucomatous neuropathy.Subjects were recruited from an urban district in Guangzhou. The target sample size was 870. Persons 50 years of age and older with 20/40 or better vision in both eyes identified as having 6 or more clock hours of angle circumference in which the pigmented trabecular meshwork was not visible under static gonioscopy in both eyes were enrolled. Each subject was randomized to undergo LI in one eye with the fellow eye left untreated. Follow up is planned for a minimum period of 3 years. Baseline examination included tonometry, limbal chamber depth grading, gonioscopy, fundus photography, anterior segment coherence tomography, ultrasound A scan, ultrasound biomicroscopy, specular microscopy and dark room provocative testing. Endpoints for the study include developing elevated intraocular pressure, peripheral anterior synechiae or experiencing acute primary angle closure.The ZAP trial will determine if LI is safe and effective at preventing pathological angle closure in asymptomatic eyes with narrow angle configurations on gonioscopy. It will also provide data on what happens to untreated eyes in PACSs. Data collected at baseline will also help identify those at high risk for developing primary angle closure and primary angle closure glaucoma.