Uncorrected Visual Impairment Research Articles

The underestimated role of myopia in uncorrectable visual impairment in the United States

We estimate the US prevalence of uncorrectable visual impairment in 2050 accounting for the changing distribution of both age and myopia. Age projections of the US population (from an estimated total of 379 million in 2050), were taken from the US census website. The distribution of myopia, by severity, was calculated from literature-derived prevalence estimates of 58.4% (≤ − 0.50 D, 2050 projection) and 33.1% (≤ − 1.00 D, 1999–2004 estimate) to provide predicted and conservative estimates, respectively. Uncorrectable visual impairment as a function of age and refractive error was modelled by multiple linear regression. Finally, the likely number of individuals in the US with visual impairment in 2050 was calculated. For a projected myopia prevalence of 58.4%, 222 million are projected to be myopic and 48 million will have high myopia (− 5 D or worse). The projected total number with uncorrectable visual impairment is 11.4 million of which 4.9 million cases (43%) of visual impairment will be directly attributed to increased risk of eye disease associated with myopia. For a projected myopia prevalence of 33.1%, 8.9 million are projected to have uncorrectable visual impairment of which 2.4 million cases (27%) will be directly attributed to myopia. It is predicted that between 27 and 43% of uncorrectable visual impairment in the US population in 2050 will be directly attributable to myopia. Failure to account for the increasing prevalence of myopia among the aging population leads to a substantial underestimate of the prevalence of visual impairment.

Dementia Prevalence and Risk Factors: Data From Rural Tanzania.

The burden of dementia is increasing in sub-Saharan Africa (SSA), but there are limited epidemiological data on dementia in SSA. This study investigated the prevalence and associations of dementia in older adults (less than 60y) attending the outpatient department of Mount Meru Hospital in Tanzania. This one-phase cross-sectional study screened a sample using the Identification of Dementia in Elderly Africans (IDEA) cognitive screening tool. Those that screened as having possible and probable dementia were further assessed, and diagnosis of dementia was made according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Demographic and risk factor data were collected. Within those screened, 57/1141 (5.0%) (95% CI: 3.7-6.3) had dementia. Female sex [odds ratio (OR)=2.778, 95% CI: 1.074-7.189], having never attended school (OR=6.088, 95% CI: 1.360-27.256), alcohol (U/wk) (OR=1.080, 95% CI: 1.016-1.149), uncorrected visual impairment (OR=4.260, 95% CI: 1.623-11.180), body mass index <18.5kg/m 2 (OR=6.588, 95% CI: 2.089-20.775), and stroke (OR=15.790, 95% CI: 3.48-74.475) were found to be significantly, independently associated with dementia. The prevalence of dementia in this population is similar to a recent community-based rate in Tanzania and lower than a hospital-based rate in Senegal. This is the first time the association between visual impairment and dementia has been reported in SSA. Other associations are in keeping with previous literature.

Preliminary evaluation of a smartphone application (DelApp) for identification of delirium in sub-Saharan Africa.

In sub-Saharan Africa, there are no validated screening tools for delirium in older adults, despite the known vulnerability of older people to delirium and the associated adverse outcomes. This study aimed to assess the effectiveness of a brief smartphone-based assessment of arousal and attention (DelApp) in the identification of delirium amongst older adults admitted to the medical department of a tertiary referral hospital in Northern Tanzania. Consecutive admissions were screened using the DelApp during a larger study of delirium prevalence and risk factors. All participants subsequently underwent detailed clinical assessment for delirium by a research doctor. Delirium and dementia were identified against DSM-5 criteria by consensus. Complete data for 66 individuals were collected of whom 15 (22.7%) had delirium, 24.5% had dementia without delirium, and 10.6% had delirium superimposed on dementia. Sensitivity and specificity of the DelApp for delirium were 0.87 and 0.62, respectively (AUROC 0.77) and 0.88 and 0.73 (AUROC 0.85) for major cognitive impairment (dementia and delirium combined). Lower DelApp score was associated with age, significant visual impairment (<6/60 acuity), illness severity, reduced arousal and DSM-5 delirium on univariable analysis, but on multivariable logistic regression only arousal remained significant. In this setting, the DelApp performed well in identifying delirium and major cognitive impairment but did not differentiate delirium and dementia. Performance is likely to have been affected by confounders including uncorrected visual impairment and reduced level of arousal without delirium. Negative predictive value was nevertheless high, indicating excellent 'rule out' value in this setting.

On classification approaches, terminology and modern principles of treatment of pathologies associated with high myopia. Part 1. Criteria for high myopia and pathological myopia

Myopic refraction is the most common ocular pathology, currently affecting about 1.5 billion people worldwide. Recent decades have seen a trend towards a significant increase in myopia prevalence, which is likely to continue in the near future. Therefore, we observe some kind of an epidemic of myopia. The greatest concern is caused by cases of uncorrectable visual impairment associated with myopia, which make pathological (degenerative) myopia one of the leading causes of low vision and blindness in many countries. At the same time, there is still no uniform interpretation of such important concepts as “high myopia” and “pathological myopia”, which can negatively affect various aspects of clinical and scientific interaction among ophthalmologists. The article provides an overview of modern work on the above issues and proposes definitions of terms to be used in the healthcare system of the Russian Federation

Relationship between visual impairment and school entrance age in rural China

ABSTRACT Clinical relevance Children with uncorrected visual impairment have lower scores on various motor and cognitive tests. Exploring the association between visual impairment and school entrance age among school children in rural China may assist in enhancing the visual health of early-entry school students. Background Educational pressures may play a role in the visual health of students. School entrance age is associated with educational pressures. This study explored whether school entrance age can contribute to visual impairment among younger generations. Methods A cross-sectional study was conducted with 17,510 students from 252 primary schools in two prefectures in western China. Information on the sampled students was collected through questionnaires and vision examinations. The relationship between visual impairment and school entrance age was further analysed by multiple regression. The school entrance age was classified as early-entry and late-entry, early-entry was defined as students entering school at the age 6 years. Results The results showed that the myopia rate of early-entry students (26.92%) was higher than late-entry students (23.86%). Multiple regression showed that visual impairment increased with the earlier age of school entry (P = 0.044). The prevalence of myopia was also significantly higher in higher grades for children of the same age. The prevalence of myopia in 10-year-old and 11-year-old fourth- and fifth-grade students was 20.6% to 30.5%, 21.7% to 27.4% (P < 0.001). The near work with eyes was significantly different among children of the same age in different grades during this study (P < 0.001). Conclusion Myopia is related to the school entrance age of children. Children who start school earlier are more likely to suffer from myopia. Educational pressures and digital screens may play a role in the association. Changes in the current education mode by reducing the study burden in the early years of learning may be significant.

Systematic review and meta-analysis of childhood visual impairment in the Eastern Mediterranean Region.

Childhood visual impairment has a significant effect on social life, educational performance, and professional choices, and can lead to poverty. To review the prevalence and causes of visual impairment among children aged 5-17 years in the Eastern Mediterranean Region (EMR). This study was conducted in 2021 using the Preferred Reporting Items for Systematic reviews and Meta- Analyses (PRISMA) method. We searched Google Scholar, PubMed, Web of Science, Scopus, Index Medicus for the Eastern Mediterranean Region, and Medline for studies published between January 2000 and April 2020. The articles included were epidemiological studies of prevalence and causes of childhood visual impairment published in peer-reviewed journals. Of the 12 705 articles screened, 23 from 9 countries met the inclusion criteria. The pooled prevalence of uncorrected, presenting, and best-corrected childhood visual impairment was 11.57%, 8.34% and 1.21%, respectively. The most common causes of childhood visual impairment were refractive error (51.89%), amblyopia (11.15%), retinal disorders (3.90%), corneal opacity (3.0%), and cataract (1.88%). There was a highly significant heterogeneity between the studies (P < 0.0001). The prevalence of visual impairment among children in the EMR was high, and the leading causes were uncorrected refractive error and amblyopia, which were avoidable. Access to eyecare services may help improve early diagnosis and treatment of preventable causes of childhood visual impairment.

Artificial intelligence and digital solutions for myopia.

Myopia as an uncorrected visual impairment is recognized as a global public health issue with an increasing burden on health-care systems. Moreover, high myopia increases one's risk of developing pathologic myopia, which can lead to irreversible visual impairment. Thus, increased resources are needed for the early identification of complications, timely intervention to prevent myopia progression, and treatment of complications. Emerging artificial intelligence (AI) and digital technologies may have the potential to tackle these unmet needs through automated detection for screening and risk stratification, individualized prediction, and prognostication of myopia progression. AI applications in myopia for children and adults have been developed for the detection, diagnosis, and prediction of progression. Novel AI technologies, including multimodal AI, explainable AI, federated learning, automated machine learning, and blockchain, may further improve prediction performance, safety, accessibility, and also circumvent concerns of explainability. Digital technology advancements include digital therapeutics, self-monitoring devices, virtual reality or augmented reality technology, and wearable devices - which provide possible avenues for monitoring myopia progression and control. However, there are challenges in the implementation of these technologies, which include requirements for specific infrastructure and resources, demonstrating clinically acceptable performance and safety of data management. Nonetheless, this remains an evolving field with the potential to address the growing global burden of myopia.

Irreversible visual loss in a tertiary care center in Saudi Arabia

Background Data on visual loss have been collected in various regions of Saudi Arabia. However, we lack data representing a wide range of different populations or reflecting changes since the first study in Saudi Arabia in 1986. Purpose The aim of this study was to determine the causes of uncorrected visual impairment and blindness in the Saudi population as presented by countrywide referrals to King Faisal Specialist Hospital and Research Center (KFSH&RC). Patients and methods This is a prospective descriptive study on all patients of all ages attending the eye clinic in KFSH&RC or referred to the Ophthalmic Consult Service with WHO definitions of visual impairment [visual acuity (VA)=20/60 or visual field (VF) <20°] and blindness (VA=20/400 or VF<10°). Best-corrected visual acuity, age, sex, and causes of visual loss were tabulated. The included patients were divided into five groups: unilateral impairment (UI), bilateral impairment (BI), unilateral blindness (UB), bilateral blindness (BB), and one impaired eye with one blind eye (BIB). Results There were 197 patients attending the ophthalmic department from May until November 2014 with WHO definition of visual impairment or blindness. Bilateral visual loss was reported in 129 (65.48%) patients. Patients from rural areas represented 78.14% of all included patients. UI, BI, UB, BB, and BIB were detected in 32 (16.24%), 56 (28.43%), 36 (18.27%), 36 (18.27%), and 37 (18.78%) patients with visual loss, respectively. Brain tumors, proliferative diabetic retinopathy, incurable myopia with extensive chorioretinal degeneration, and glaucoma were the main causes of visual loss. Conclusion The study contributed to a global database for the different causes of irreversible visual loss in Saudi Arabia. Furthermore, the design and provision of low vision aids and social support can be targeted to appropriately identified subgroups of our population.

The impact of uncorrected refractive error and visual impairment on the quality of life amongst school-going children in Sekhukhune district (Limpopo), South Africa

Background: Uncorrected refractive error (URE) and subsequent visual impairment (VI) is expected to have an impact on the quality of life (QoL) amongst schoolchildren.Aim: This study aimed to determine the impact of URE and VI on the QoL amongst school-going children aged 14–18 years.Settings: The study was performed at Sekhukhune district in the Limpopo province, South Africa.Methods: The tool used to assess the QoL was the National Eye Institute Quality of Life Questionnaire (NEI-VFQ-25). A modified refractive error study in children (RESC) protocol was employed to determine the value of URE and VI. The tests performed included Logarithm of the Minimum Angle of Resolution (LogMAR) visual acuity, cycloplegic autorefraction, binocular motor function tests, media and fundus examination.Results: A total of 154 learners, aged 14–18 years completed the NEI-VFQ-25, which was offered in an interview format. A total of 56 learners (36.3%, 95% confidence interval [CI]: 14.9–27.9]) had URE and VI. Children with URE and VI scored low on the NEI-VFQ-25 as compared with those without URE and VI.Conclusion: Uncorrected refractive error has an impact on the QoL of learners in the greater Sekhukhune district. This calls for policymakers and other relevant stakeholders in basic education to prioritise programmes that seek to address the visual health of scholars in rural schools.

Factors influencing post-screening visits of students to local vision centres in rural northwest China

ABSTRACT Clinical relevance Children with uncorrected visual impairment have lower scores on a variety of motor and cognitive tests. Exploring the influencing factors of low-income groups seeking vision care services is helpful for identifying relevant barriers and necessary measures to improve the utilization rate of vision care services. Background The community-based vision center (VC) is a popular model for solving vision problem of students in rural China. Compliance is the key factor to the success of the VC model. Factors determining compliance with visitations to VC among primary school students after screening were explored. Methods A cross-sectional study was conducted with 15,763 students from 228 primary schools. Information was collected through questionnaires and vision examinations. The determinants that affect visits of students to the VC were analyzed using logistic regression. Results Among the 15,763 sample, 5,361 (34%) students had a visual impairment. At baseline, only 962 (18%) of students with visual impairment sought vision care services. After a local VC was established, among the 5,163 students who needed to be referred, only 2,237 (43.33%) students visited the VC. Multivariate logistic regression models for predicting students visit the VC revealed that the following characteristics were significant predictors: poor uncorrected visual acuity (P < 0.001), a higher grade level (P = 0.008; P = 0.010), ‘left-behind’ children (P < 0.001), short living distance between home and the VC (P < 0.001), and the fact that these students lived in Gansu province (P < 0.001). Conclusions Establishing a VC that provides students with vision screening and free vision care services can increase the rate of seeking vision health services for students in rural areas, but the compliance rate still needs to be improved. The influencing factors for student compliance have been identified.

Socio-demographic disparities in amblyopia prevalence among 1.5 million adolescents.

Amblyopia, when not diagnosed at appropriate age, leads to uncorrectable visual impairment with considerable social and financial implications. The aim of this study was to assess socio-demographic disparities in amblyopia prevalence among Israeli adolescents, in order to identify susceptible groups in the population. A nationwide, population-based, cross-sectional study of Israeli adolescents examined between 1993 and 2017. All study participants underwent visual acuity examination with socio-demographic data and previous medical history documented. Associations were analyzed using univariable and multivariable logistic regression models. Among 1 334 650 Israeli-born candidates aged 17.15±0.26 years, amblyopia was diagnosed in 1.07%. The overall prevalence of amblyopia has declined from 1.59% in 1993 to 0.87% in 2017. Being in the lowest socioeconomic status and below average cognitive function scores increased the odds of amblyopia in both males [odds ratio (OR) 1.64, 95% confidence interval (CI) 1.45-1.87; OR 1.27, 95% CI 1.19-1.35, respectively] and females (OR 1.61, 95% CI 1.30-1.98; OR 1.27, 95% CI 1.18-1.36, respectively). Among males, Orthodox and ultra-Orthodox educational systems were associated with increased odds of amblyopia (OR 1.16, 95% CI 1.09-1.25; OR 1.90, 95% CI 1.73-2.09). A significantly higher prevalence of amblyopia was recorded among 219 983 immigrants (1.51%, P<0.001). Although the overall prevalence of amblyopia has decreased during the observed years, we found substantial evidence of socio-demographic disparities in amblyopia prevalence among adolescents, suggesting disparities in the prevention of the disease and its treatment. Demonstration of inequities at a national level could aid future guidance of health policy and augment current vision screening programs.

Visual acuity and refractive findings in children prescribed glasses from a school-based vision program

School-based vision programs (SBVPs) serve disadvantaged communities with higher prevalence of uncorrected visual impairment. We report the vision improvement and refractive profiles in children prescribed glasses from a SBVP in Baltimore, Maryland.

426 PREVALENCE OF, AND RISK FACTORS FOR, DEMENTIA IN ADULT OUTPATIENT REFERRALS TO A REGIONAL REFERRAL HOSPITAL IN ARUSHA, TANZANIA

Abstract Introduction The global burden of dementia is increasing, with the greatest increase predicted to occur in sub-Saharan Africa (SSA). Despite this there are limited previous data on the prevalence of, and risk factors for, dementia in SSA. This study aimed to estimate the prevalence of dementia, and investigate its associations, in those aged 60 years and older attending the outpatient department of Mount Meru Hospital in northern Tanzania. This is the first hospital-based outpatient dementia prevalence and risk factors study to be conducted in an east African population. Methods This was a one-phase cross-sectional study. Adults aged 60 years and over attending medical outpatients were screened for dementia using The Identification and Intervention for Dementia in Elderly Africans cognitive screening tool. Those who scored ≤9 were clinically assessed using the DSM-IV criteria. Demographic, medical comorbidity and lifestyle information were collected during a clinical assessment. Results Prevalence of dementia was 5.0% (95% confidence interval: 3.7–6.3). Binary logistic regression found female sex (odds ratio (OR) = 2.778), having no formal education (OR = 6.088), quantity of alcohol consumption (units/week) (OR = 1.080), uncorrected visual impairment (OR = 4.260), body mass index &amp;lt;18.5 kg/m2 (OR = 6.588) and stroke (OR = 15.790 with wide 95% confidence interval (3.48–74.475)) to be significantly, independently associated with dementia. Conclusions The prevalence of dementia in this population is lower than previously reported community-based rates in Tanzania, and similar to those in high-income countries. This is the first time the association between uncorrected visual impairment and dementia has been reported in SSA. Other associations identified are in keeping with previous literature. Further research on the management of dementia and its risk factors, and the support and education of carers and patients in east African populations is required.

Prevalence of refractive error and visual impairment among school-age children of Hargesia, Somaliland, Somalia.

Childhood visual impairment is a global public health problem, especially in low and middle-income countries. Its most common causes are avoidable by early diagnosis and treatment. To assess prevalence of refractive error and visual impairment among school-aged children in Hargeisa, Somaliland, Somalia. This was a cross-sectional study of 1204 students (aged 6-15 years) in 8 randomly selected primary schools in Hargeisa from November 2017 to January 2018. We used the modified Refractive Error Study in Children to determine prevalence of refractive error and visual impairment, including the following investigations: distance visual acuity, assessed by Snellen Tumbling E-chart; refraction, assessed by retinoscope binocular vision assessment; and examination of anterior and posterior segments. Prevalence of uncorrected, presenting and best-corrected visual impairment of 6/12 or worse was 13.6%, 7.6% and 0.75%, respectively. Only 16 of 91 (17.6%) children were using spectacles and the rest were unaware of the problem. Refractive error was the cause of visual impairment in 76.8% of participants, amblyopia in 22.0%, trachoma in 2.4%, and corneal opacity and cataract in 0.6%. Anterior segment abnormalities were found in 8.3%, mainly vernal keratoconjunctivitis, while posterior abnormalities were observed in 0.7%. Prevalence of myopia was 9.1%, hypermetropia 2.7% and astigmatism 3.9%. Prevalence of visual impairment because of Refractive Error was associated with increasing age, but there was no significant association with school grade or sex. Prevalence of visual impairment among school-aged children in Hargeisa was high, and the leading cause was uncorrected Refractive Error. There are barriers to care and it is critical that they are overcome.

Visual impairment andrefractive error in school children in Bhutan: The findings from the Bhutan School Sight Survey (BSSS 2019).

To estimate the nationwide prevalence of visual impairment and associated refractive error in school children in Bhutan. The sample of this prospective cross-sectional national survey comprised of randomly selected classes in levels IV-IX (age 10 to 15 years) from schools throughout Bhutan. The examination included measurement of visual acuity (VA), evaluation of ocular motility, refraction under cycloplegia, examination of the external eye, media and fundus. The principal cause of impairment was determined for eyes with uncorrected VA ≤6/12. The main outcome measures were distance VA and cycloplegic refractive error. With a sampling frame of 1967 class-based clusters from 190 schools, 160 classes in 103 schools were randomly selected; 4985 (98.5%) of 5060 enumerated children were examined. The prevalence of uncorrected, presenting, and best-corrected visual impairment (VA≤6/12) in the better eye was 14.5%, 12.8%, and 0.34%, respectively. Refractive error was the principal cause (94.2%) of impaired vision and 88% of children who could achieve VA ≥6/9 with best correction were without necessary spectacles. The prevalence of myopia (≤ -0.5 D) was 6.64% and was associated with female gender (P = 0.004), urban schooling (P = 0.002), and greater parental education (P<0.001). The prevalence of hyperopia (≥ +2.0 D) was 2.17% and was significantly associated with lower class-level (P = 0.033), and female gender (P = 0.025). The overall prevalence of astigmatism (≥ 0.75 D) was 9.75%. Reduced vision because of uncorrected refractive error is a public health problem among school-age children in Bhutan. Effective school eye health strategies are needed to eliminate this easily treatable cause of visual impairment.

Prevalence of Refractive Error, Presbyopia, and Spectacle Coverage in Bogotá, Colombia: A Rapid Assessment of Refractive Error.

Uncorrected refractive error is the leading cause of visual impairment; therefore, reducing its prevalence is important worldwide. For two decades, there has not been a comprehensive assessment of refractive error in Latin America. The purpose of this study was to determine the current prevalence of refractive error, presbyopia, spectacle coverage, barriers to uptake refractive services, and spectacle correction in people 15 years and older in Bogotá, Colombia. A cross-sectional community-based survey was conducted using 50 randomly selected clusters from 10 districts of Bogotá reflecting the socioeconomic status of the city. Respondents 15 years and older were interviewed and underwent standardized clinical eye examinations. Prevalence of uncorrected refractive error, spectacle coverage, and visual impairment were standardized to 2015 age-sex population distribution of Bogotá and further analyzed. A total of 2886 subjects (90% of 3206 eligible subjects) participated in the study; 39.1% were male and 60.9% were female in the age range of 15 to 96 years, with a median age of 46 years (interquartile range, 45 to 54 years). Age- and sex-standardized prevalence of visual impairment was 19.3% (95% confidence interval [CI], 17.8 to 20.8%). Prevalence of uncorrected refractive error was 12.5% (95% CI, 11.3 to 13.7%). Prevalence of presbyopia among participants 35 years and older was 55.2% (95% CI, 52.9 to 57.4%). Spectacle coverage was 50.9% for distance vision, and it was 33.9% for presbyopia. Main barrier to spectacle uptake was a limitation in affording spectacles because of economic factors (29.5%). This study provides a current estimate of refractive error using the Rapid Assessment of Refractive Error for Colombia and the Latin American region. The prevalence of uncorrected refractive error and presbyopia was high, and the barriers to spectacle uptake were higher in the lowest socioeconomic strata. The results obtained in the present study will help in making evidence-based decisions related to eye care service delivery in Colombia.

Prevalence of refractive error and spectacle coverage in schoolchildren in two urban areas of Chile.

ABSTRACTObjective.To assess the impact of efforts to reduce visual impairment by detecting and treating refractive errors (REs) among schoolchildren in two urban areas of Chile.Methods.In 2013, in the communities of Concepción and La Florida, we conducted a multicenter, multistage-sampling, cross-sectional study employing methods used by the Refractive Error Study in Children (RESC) survey. Best-corrected visual acuity was assessed using pinhole, with and without glasses. The coverage for correcting visual impairment due to refractive error was estimated.Results.We examined 5 412 schoolchildren, in the communities of Concepción (n = 3 049) and La Florida (n = 2 363). Uncorrected visual acuity (VA) of > 0.63 in at least one eye was found in 4 721 children (87.23%; 95% confidence interval (CI): 86.58%–88.30%). Of the remaining children, 1 017 of them (18.79%; 95% CI: 17.78%–19.80%) had a VA of < 0.5 in at least one eye. Of the 691 children with uncorrected visual impairment with both eyes open (12.77%; 95% CI: 11.9%–13.64%), 476 of them (8.76%; 95% CI: 8.03%–9.49%) achieved normal vision using best possible correction, and with 271 of the 476 (56.93%) having a normal presenting VA in the better eye.Conclusions.We found an increased coverage of services for RE-associated visual impairment and an increased percentage of children wearing glasses as compared to values reported for La Florida in an article published in 2000. The National Board of School Aid and Scholarships (JUNAEB) in Chile is achieving better results in its schoolchildren eye care program.

Association of Axial Length With Risk of Uncorrectable Visual Impairment for Europeans With Myopia

Myopia (ie, nearsightedness) is becoming the most common eye disorder to cause blindness in younger persons in many parts of the world. Visual impairment due to myopia is associated with structural changes of the retina and the globe because of elongation of the eye axis. How axial length-a sum of the anterior chamber depth, lens thickness, and vitreous chamber depth-and myopia relate to the development of visual impairment over time is unknown. To evaluate the association between axial length, spherical equivalent, and the risk of visual impairment and to make projections of visual impairment for regions with high prevalence rates. This cross-sectional study uses population-based data from the Rotterdam Study I (1990 to 1993), II (2000 to 2002), and III (2006 to 2008) and the Erasmus Rucphen Family Study (2002 to 2005) as well as case-control data from the Myopia Study (2010 to 2012) from the Netherlands. In total, 15 404 individuals with data on spherical equivalent and 9074 individuals with data on axial length were included in the study; right eyes were used for analyses. Data were analyzed from September 2014 to May 2016. Visual impairment and blindness (defined according to the World Health Organization criteria as a visual acuity less than 0.3) and predicted rates of visual impairment specifically for persons with myopia. Of the 15 693 individuals included in this study, the mean (SD) age was 61.3 (11.4) years, and 8961 (57.1%) were female. Axial length ranged from 15.3 to 37.8 mm; 819 individuals had an axial length of 26 mm or greater. Spherical equivalent ranged from -25 to +14 diopters; 796 persons had high myopia (ie, a spherical equivalent of -6 diopters or less). The prevalence of visual impairment varied from 1.0% to 4.1% in the population-based studies, was 5.4% in the Myopia Study, and was 0.3% in controls. The prevalence of visual impairment rose with increasing axial length and spherical equivalent, with a cumulative incidence (SE) of visual impairment of 3.8% (1.3) for participants aged 75 years with an axial length of 24 to less than 26 mm and greater than 90% (8.1) with an axial length of 30 mm or greater. The cumulative risk (SE) of visual impairment was 5.7% (1.3) for participants aged 60 years and 39% (4.9) for those aged 75 years with a spherical equivalent of -6 diopters or less. Projections of these data suggest that visual impairment will increase 7- to 13-fold by 2055 in high-risk areas. This study demonstrated that visual impairment is associated with axial length and spherical equivalent and may be unavoidable at the most extreme values in this population. Developing strategies to prevent the development of myopia and its complications could help to avoid an increase of visual impairment in the working-age population.

Patient-Centered Outcome Measures to Assess Functioning in Randomized Controlled Trials of Low-Vision Rehabilitation: A Review.

Low-vision rehabilitation (LVR) aims to improve the functioning of patients with chronic uncorrectable visual impairment. LVR is inherently a patient-centered intervention since its approach and goals are dictated by the needs and abilities of each individual patient. Accordingly, it is essential to have patient-centered outcome (PCO) measures to assess and compare the efficacy and effectiveness of low-vision interventions; however, there is a lack of evidence on the effectiveness of LVR interventions. We reviewed the literature in order to identify randomized controlled trials (RCTs) in the field of LVR and the outcome measures used to assess patient functioning in these trials. We identified 15 RCTs of LVR that employed nine unique patient-reported, five unique performance-based, and one hybrid (combined patient-reported and performance) outcome measures. Since these trials used distinct tools to assess patient functioning, it is difficult to compare the effectiveness of competing rehabilitation interventions across studies. Selecting valid outcome measures that are both relevant to LVR goals of specific patient populations and that measure functioning across a range of visually demanding tasks could improve the ability to detect the effect of LVR and to compare rehabilitation strategies. There are advantages and limitations to the use of both patient-reported and performance-based outcome measures, and additional work should be undertaken to explore the relationship between these modes of assessment, as well as strategies for optimally integrating these approaches. Careful selection of outcome measures in the design of future RCTs in LVR may lead to improved understanding of the effectiveness of LVR and, ultimately, to improved functioning of patients with low vision.

The Role of Atropine Eye Drops in Myopia Control.

High myopia is a major cause of uncorrectable visual impairment. It imposes major challenges and costs for refractive correction, and for the treatment of associated pathological complications. In the last 60 years, there has been a marked increase in the prevalence of high myopia in younger generations in developed countries in East and Southeast Asia, and there are signs of similar, but less pronounced increases in North America and Europe. In some parts of the world, 70-90% of children completing high schools are now myopic, and as many as 20% may be highly myopic. It is now clear that myopia results from excessive axial elongation of the eye, and this greater rate of axial elongation appears to be environmentally driven. Experimental studies have examined the biochemical mechanisms involved in regulation of axial elongation; and, from these studies, some options have emerged for preventing the development of myopia or slowing myopia progression. Atropine eye drops have been quite extensively used in clinical practice in Asian countries. This long-lasting treatment could be beneficial, but has clear limitations and complications. Recent reports suggest that a low concentration of atropine, which has less severe side-effects, is also effective. But, a decision to use an invasive treatment such as atropine drops, even at low doses, requires careful consideration of the risk of myopia progression. A decision to use atropine in pre-myopic patients would require even more careful consideration of the risks. Here, we review the current literature relevant to the prevention of myopia progression with atropine drops.