A large-scale analysis of refractive errors in students attending public primary schools in Mexico.

A cross-sectional, retrospective study was conducted from September 2013 through July 2014 to determine the prevalence of refractive errors among students attending public primary schools in Mexico. Among 3,861,156 students at 14,566 public primary schools in all 32 states of Mexico, teachers identified reduced visual acuity in 1,253,589 (32.5%) using visual acuity measurement. Optometrists confirmed 391,498 [31.2%, mean (SD) age: 8.8 (1.9) years; 204,110 girls (52.9%)] had refractive errors using visual acuity measurement and noncycloplegic static retinoscopy. Among 288,537 (72.4%) of children with previous eyeglasses usage data reported, 241,505 (83.7%) had uncorrected refractive errors. Before prescription eyeglasses were provided, 281,891 students (72%) had logMAR visual acuity ≤ 0.2; eyeglasses corrected vision loss in 85.6% (n = 241,352) of them. Simple myopic astigmatism was the most frequent refractive error (25.7%, n = 100,545). Astigmatism > - 1.00 diopters was present in 54.6% of all students with ametropia. The anisometropia rate based on spherical equivalent difference between right and left eye ≥ 1.50 diopters was 3.9% (n = 15,402). Uncorrected refractive errors are an important issue in primary school students in Mexico. An updated study is needed to analyze the evolving trends over the past decade.

Estimating mortality and disability in Peru before the COVID-19 pandemic: a systematic analysis from the Global Burden of the Disease Study 2019.

Background: Estimating and analyzing trends and patterns of health loss are essential to promote efficient resource allocation and improve Peru's healthcare system performance. Methods: Using estimates from the Global Burden of Disease (GBD), Injuries, and Risk Factors Study (2019), we assessed mortality and disability in Peru from 1990 to 2019. We report demographic and epidemiologic trends in terms of population, life expectancy at birth (LE), mortality, incidence, prevalence, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) caused by the major diseases and risk factors in Peru. Finally, we compared Peru with 16 countries in the Latin American (LA) region. Results: The Peruvian population reached 33.9 million inhabitants (49.9% women) in 2019. From 1990 to 2019, LE at birth increased from 69.2 (95% uncertainty interval 67.8-70.3) to 80.3 (77.2-83.2) years. This increase was driven by the decline in under-5 mortality (-80.7%) and mortality from infectious diseases in older age groups (+60 years old). The number of DALYs in 1990 was 9.2 million (8.5-10.1) and reached 7.5 million (6.1-9.0) in 2019. The proportion of DALYs due to non-communicable diseases (NCDs) increased from 38.2% in 1990 to 67.9% in 2019. The all-ages and age-standardized DALYs rates and YLLs rates decreased, but YLDs rates remained constant. In 2019, the leading causes of DALYs were neonatal disorders, lower respiratory infections (LRIs), ischemic heart disease, road injuries, and low back pain. The leading risk factors associated with DALYs in 2019 were undernutrition, high body mass index, high fasting plasma glucose, and air pollution. Before the COVID-19 pandemic, Peru experienced one of the highest LRIs-DALYs rates in the LA region. Conclusion: In the last three decades, Peru experienced significant improvements in LE and child survival and an increase in the burden of NCDs and associated disability. The Peruvian healthcare system must be redesigned to respond to this epidemiological transition. The new design should aim to reduce premature deaths and maintain healthy longevity, focusing on effective coverage and treatment of NCDs and reducing and managing the related disability.

Preventable risk factors for type 2 diabetes can be detected using noninvasive spontaneous electroretinogram signals.

Given the ever-increasing prevalence of type 2 diabetes and obesity, the pressure on global healthcare is expected to be colossal, especially in terms of blindness. Electroretinogram (ERG) has long been perceived as a first-use technique for diagnosing eye diseases, and some studies suggested its use for preventable risk factors of type 2 diabetes and thereby diabetic retinopathy (DR). Here, we show that in a non-evoked mode, ERG signals contain spontaneous oscillations that predict disease cases in rodent models of obesity and in people with overweight, obesity, and metabolic syndrome but not yet diabetes, using one single random forest-based model. Classification performance was both internally and externally validated, and correlation analysis showed that the spontaneous oscillations of the non-evoked ERG are altered before oscillatory potentials, which are the current gold-standard for early DR. Principal component and discriminant analysis suggested that the slow frequency (0.4-0.7 Hz) components are the main discriminators for our predictive model. In addition, we established that the optimal conditions to record these informative signals, are 5-minute duration recordings under daylight conditions, using any ERG sensors, including ones working with portative, non-mydriatic devices. Our study provides an early warning system with promising applications for prevention, monitoring and even the development of new therapies against type 2 diabetes.

Wikipedia, friend or foe regarding information on diabetic retinopathy? A content analysis in the world's leading 19 languages.

OBJECTIVE: To compare the completeness and quality of information about diabetic retinopathy on Wikipedia in the world's leading spoken languages in 2020. DESIGN AND METHODS: An observational, descriptive, cross-sectional study. The information on diabetic retinopathy obtained from the free encyclopedia Wikipedia® was assessed in languages with one hundred million or more total speakers. The term "diabetic retinopathy" was accessed in the corresponding Wikipedia entry in English, while the "more languages" function gives access to other languages. The information on the sites was collected by three ophthalmologist observers. A database was created with the most important subtopics for the education of patients with diabetic retinopathy in any of its classifications, based on a 25-question survey. The results were stratified on a scale from 0 to 4. A confirming correlation was found in the statistical analysis among the observers. RESULTS: No language achieved the label "excellent"; 2 languages were rated as "fair "; 4 languages qualified as "substandard"; and 7 languages were scored as "poor." No information could be found in five languages. CONCLUSIONS: As would be expected, the quality of content is variable across different languages. However, if anyone can edit Wikipedia, health professionals can do so as well to improve the quality and quantity of information for patients.

Central Macular Thickness in a Healthy Mexican Population Using Huvitz Optical Coherence Tomography.

OBJECTIVE: To determine normal macular thickness values in a healthy Mexican population and its variation by age and gender using Huvitz spectral-domain optical coherence tomography (HOCT-1F). METHODS: This cross-sectional study included 211 consecutive eyes from clinically normal subjects (66 men, 145 women) between October 2018 and December 2018, with best-corrected visual acuities better than 20/30. One eye was selected for the macular scan using the Huvitz OCT (Huvitz OCT-1F, HOCT-1F, Huvitz Co., Ltd., Republic of Korea) with an automated segmentation algorithm. Three vertical and horizontal scans, centered on the fovea with an area of 9 mm, and a color 45° fundus photograph were obtained using Huvitz OCT-1F. Macular measurements were presented as means with standard deviations values for each of the nine regions defined by the Early Treatment Diabetic Retinopathy Study (ETDRS). RESULTS: The mean age was 34.3±11.9 years. Using the ETDRS map, the mean central subfield thickness (CST) was 227.4±18.9 µm. Male gender was associated with greater CST (P<0.001) compared to females. There was no association between mean macular CST (r2=0.011; P=0.11) and age. Macular thickness was thicker in the inner ring than in the outer ring, and there were no significant differences in mean CST among age groups (P=0.70). CONCLUSION: Normal macular thickness values using the Huvitz OCT in a Mexican healthy population aged from 18-70 years were thinner in the foveal macular region than values reported in other populations. Female patients had a thinner CST, and age was not correlated with macular thickness.

Rapid assessment of avoidable blindness: Prevalence of blindness, visual impairment and diabetes in nuevo leon, Mexico 2014.

PURPOSE: To estimate the prevalence of blindness, visual impairment, diabetes mellitus, and diabetic retinopathy in patients aged 50 years and older in the State of Nuevo León, Mexico. METHODS: Ninety-one clusters of 60 people aged 50+ were selected randomly and a rapid assessment of avoidable blindness (RAAB) was conducted. Participants had their visual acuity and cause of visual impairment assessed, underwent a random glucose test and fundoscopy under mydriasis if they had diabetes. The diabetic retinopathy (DR) degree was classified according to the Scottish diabetic retinopathy grading scheme. RESULTS: From the sample 5,055 (92.6%) people were examined. The blindness prevalence was 1.7% (95% Confidence Interval: 1.3-2.1%). Cataract (32.6%), DR (29.1%) and glaucoma (16.3%) were the leading causes of blindness. The prevalence of severe, moderate, and early visual impairment was 1.0%, 5.1%, and 7.7%, respectively. Among respondents, 31% had diabetes and 8.1% of them was not diagnosed prior to the study. Of all participants with diabetes, 50% had glucose levels of 200 mg/dl or higher and 15.7% had sight-threatening diabetic retinopathy. CONCLUSIONS: Besides strengthening of cataract intervention activities, more ophthalmic services for diabetic retinopathy and glaucoma control are needed in Nuevo León to provide timely intervention to prevent blindness.

Analysis of ophthalmological and vision-related publications in Latin America.

PURPOSE: To assess scientific production related to ophthalmology and vision in Latin America during the period from 2006 to 2015. METHODS: The PubMed, Lilacs (Bireme), Google Scholar, SciELO, and Medigraphic databases were evaluated for this retrospective, descriptive, and comparative study. RESULTS: A total of 1,510 articles was identified. Brazil was the leader in quantitative production in ophthalmology, averaging 85.4 articles per year. Mexico was in second place with 27.4, and Argentina was in third place with 11.1 articles per year. Forty-one percent of articles were published in English, 28.1% dealt with the subspecialty of the retina, and 63% were published by researchers affiliated with universities. The frequency of male first authors was 58.9%, and the journal Arquivos Brasileiros de Oftalmologia accounted for 36.42% of the identified articles. CONCLUSIONS: Brazil stands in first place in Latin America in ophthalmologic scientific production. Nearly half of the researchers in ophthalmology in Latin America included in our study were listed in databases other than PubMed.

Analysis of ophthalmological and vision-related publications in Latin America / Análise de publicações oftalmológicas e relacionadas à visão na América Latina

ABSTRACT Purpose: To assess scientific production related to ophthalmology and vision in Latin America during the period from 2006 to 2015. Methods: The PubMed, Lilacs (Bireme), Google Scholar, SciELO, and Medigraphic databases were evaluated for this retrospective, descriptive, and comparative study. Results: A total of 1,510 articles was identified. Brazil was the leader in quantitative production in ophthalmology, averaging 85.4 articles per year. Mexico was in second place with 27.4, and Argentina was in third place with 11.1 articles per year. Forty-one percent of articles were published in English, 28.1% dealt with the subspecialty of the retina, and 63% were published by researchers affiliated with universities. The frequency of male first authors was 58.9%, and the journal Arquivos Brasileiros de Oftalmologia accounted for 36.42% of the identified articles. Conclusions: Brazil stands in first place in Latin America in ophthalmologic scientific production. Nearly half of the researchers in ophthalmology in Latin America included in our study were listed in databases other than PubMed.

RESUMO Objetivo: Avaliar a produção científica relacionada à oftalmologia e à visão na América Latina durante o período de 2006 a 2015. Métodos: As bases de dados PubMed, Lilacs (Bireme), Google Scholar, SciELO e Medigraphic foram utilizadas para realizar um estudo retrospectivo, descritivo e comparativo. Resultados: Foram identificados 1,510 artigos, sendo que o Brasil foi a principal fonte de produção quantitativa, com uma média de 85,4 artigos por ano; o México aparece em segundo lugar com 27,4 e a Argentina em terceiro lugar com 11,1 artigos por ano. Quarenta e um por cento dos artigos foram publicados em inglês; 28,1% trataram da subespecialidade da retina; e a principal fonte institucional de publicações foram as universidades, com 63%. A frequência de primeiros autores do sexo masculino foi de 58,9%, e a revista Arquivos Brasileiros de Oftalmologia representou 36,42% dos artigos identificados. Conclusões: O Brasil ocupa o primeiro lugar na América Latina na produção científica oftalmológica. Os bancos de dados não indexados no PubMed foram incluídos em nosso estudo, representam quase metade dos pesquisadores em oftalmologia na América Latina.

The cataract situation in Latin America: barriers to cataract surgery.

PURPOSE: To provide an update of cataract data and barriers to cataract surgery in Latin America. DESIGN: Review and longitudinal study. METHODS: Cataract surgery rates and other related indicators that have been reported to the VISION 2020 Latin America program since 2005 were reviewed. PubMed was searched for publications concerning regional epidemiologic studies related to cataract, cataract surgery, barriers, outcomes, and cataract prevalence between January 2012 and October 2013 to obtain the most up-to-date data from 19 countries. RESULTS: The weighted mean regional cataract surgery rate has increased by an impressive 70% since 2005, from 1562 to 2672 cataract surgeries per 1 million inhabitants. The weighted mean number of ophthalmologists per 1 million inhabitants in the region is approximately 62. Cataract surgery coverage varies widely in Latin America, from a meager 15% in El Salvador to a more satisfactory 77% in Uruguay. Five recent surveys indicate that lack of awareness of cataract and the surgery treatment option as well as the cost of the surgery are the main barriers to cataract surgery. CONCLUSIONS: In spite of the increasing rates of cataract surgery and the more-than-adequate number of ophthalmologists in Latin America, it is not known how many ophthalmologists actually perform surgery. Coverage remains less than satisfactory across the region. Barriers to cataract surgery hinder the efforts of eye care programming. More comprehensive eye care programs and training centers are needed so that they can focus on reaching the underserved and unaware communities, increase surgery output and uptake, and improve outcomes.

Risk factors of age-related macular degeneration in Argentina.

PURPOSES: To assess the risk factors of age-related macular degeneration in Argentina using a case-control study. METHODS: Surveys were used for subjects' antioxidant intake, age/gender, race, body mass index, hypertension, diabetes (and type of treatment), smoking, sunlight exposure, red meat consumption, fish consumption, presence of age-related macular degeneration and family history of age-related macular degeneration. Main effects models for logistic regression and ordinal logistic regression were used to analyze the results. RESULTS: There were 175 cases and 175 controls with a mean age of 75.4 years and 75.5 years, respectively, of whom 236 (67.4%) were female. Of the cases with age-related macular degeneration, 159 (45.4%) had age-related macular degeneration in their left eyes, 154 (44.0%) in their right eyes, and 138 (39.4%) in both eyes. Of the cases with age-related macular degeneration in their left eyes, 47.8% had the dry type, 40.3% had the wet type, and the type was unknown for 11.9%. The comparable figures for right eyes were: 51.9%, 34.4%, and 13.7%, respectively. The main effects model was dominated by higher sunlight exposure (OR [odds ratio]: 3.3) and a family history of age-related macular degeneration (OR: 4.3). Other factors included hypertension (OR: 2.1), smoking (OR: 2.2), and being of the Mestizo race, which lowered the risk of age-related macular degeneration (OR: 0.40). Red meat/fish consumption, body mass index, and iris color did not have an effect. Higher age was associated with progression to more severe age-related macular degeneration. CONCLUSION: Sunlight exposure, family history of age-related macular degeneration, and an older age were the significant risk factors. There may be other variables, as the risk was not explained very well by the existing factors. A larger sample may produce different and better results.

Visual acuity and refraction by age for children of three different ethnic groups in Paraguay.

PURPOSE: To characterize refractive errors in Paraguayan children aged 5-16 years and investigate effect of age, gender, and ethnicity. METHODS: The study was conducted at 3 schools that catered to Mennonite, indigenous, and mixed race children. Children were examined for presenting visual acuity, autorefraction with and without cycloplegia, and retinoscopy. Data were analyzed for myopia and hyperopia (SE ≤-1 D or -0.5 D and ≥2 D or ≥3 D) and astigmatism (cylinder ≥1 D). Spherical equivalent (SE) values were calculated from right eye cycloplegic autorefraction data and analyzed using general linear modelling. RESULTS: There were 190, 118, and 168 children of Mennonite, indigenous and mixed race ethnicity, respectively. SE values between right/left eyes were nonsignificant. Mean visual acuity (VA) without correction was better for Mennonites compared to indigenous or mixed race children (right eyes: 0.031, 0.090, and 0.102 logMAR units, respectively; P<0.000001). There were 2 cases of myopia in the Mennonite group (1.2%) and 2 cases in the mixed race group (1.4%) (SE ≤-0.5 D). The prevalence of hyperopia (SE ≥2 D) was 40.6%, 34.2%, and 46.3% for Mennonite, indigenous and mixed race children. Corresponding astigmatism rates were 3.2%, 9.5%, and 12.7%. Females were slightly more hyperopic than males, and the 9-11 years age group was the most hyperopic. Mennonite and mixed race children were more hyperopic than indigenous children. CONCLUSIONS: Paraguayan children were remarkably hyperopic and relatively free of myopia. Differences with regard to gender, age, and ethnicity were small.

Risk factors of age-related macular degeneration in Argentina / Fatores de risco para degeneração macular relacionada à idade na Argentina

PURPOSES: To assess the risk factors of age-related macular degeneration in Argentina using a case-control study. METHODS: Surveys were used for subjects' antioxidant intake, age/gender, race, body mass index, hypertension, diabetes (and type of treatment), smoking, sunlight exposure, red meat consumption, fish consumption, presence of age-related macular degeneration and family history of age-related macular degeneration. Main effects models for logistic regression and ordinal logistic regression were used to analyze the results. RESULTS: There were 175 cases and 175 controls with a mean age of 75.4 years and 75.5 years, respectively, of whom 236 (67.4%) were female. Of the cases with age-related macular degeneration, 159 (45.4%) had age-related macular degeneration in their left eyes, 154 (44.0%) in their right eyes, and 138 (39.4%) in both eyes. Of the cases with age-related macular degeneration in their left eyes, 47.8% had the dry type, 40.3% had the wet type, and the type was unknown for 11.9%. The comparable figures for right eyes were: 51.9%, 34.4%, and 13.7%, respectively. The main effects model was dominated by higher sunlight exposure (OR [odds ratio]: 3.3) and a family history of age-related macular degeneration (OR: 4.3). Other factors included hypertension (OR: 2.1), smoking (OR: 2.2), and being of the Mestizo race, which lowered the risk of age-related macular degeneration (OR: 0.40). Red meat/fish consumption, body mass index, and iris color did not have an effect. Higher age was associated with progression to more severe age-related macular degeneration. CONCLUSION: Sunlight exposure, family history of age-related macular degeneration, and an older age were the significant risk factors. There may be other variables, as the risk was not explained very well by the existing factors. A larger sample may produce different and better results.

OBJETIVO: Determinar os fatores de risco para degeneração macular relacionada à idade na Argentina utilizando um estudo caso-controle. MÉTODOS: Questionários foram usados para a obtenção de informações dos participantes em relação à ingesta de antioxidantes, idade/sexo, raça, índice de massa corporal, hipertensão, diabetes (e tipo de tratamento), tabagismo, exposição à luz solar, consumo de carne vermelha/peixe, presença de degeneração macular relacionada à idade e história familiar de degeneração macular relacionada à idade. Modelos de efeito principal para regressão logística e regressão logística ordinal foram usados para analisar os resultados. RESULTADOS: Foram recrutados 175 casos e 175 controles com uma média de idade de 75,4 anos e 75,5, respectivamente, dos quais 236 (67,4%) eram mulheres. Cento e cinquenta e nove (45,4%) tinham degeneração macular relacionada à idade em seus olhos esquerdos, 154 (44,0%) em seus olhos direitos, e 138 (39,4%) em ambos os olhos. Entre os casos de degeneração macular relacionada à idade no olho esquerdo, 47,8% apresentavam o tipo seca, 40,3% o tipo úmida, e o tipo era desconhecido em 11,9%. Os achados para os olhos direitos foram: 51,9%, 34,4% e 13,7%, respectivamente. O modelo de efeito principal foi dominado por maior exposição à luz solar (OR [odds ratio]: 3,3) e história familiar de degeneração macular relacionada à idade (OR: 4,3). Outros fatores incluindo hipertensão (OR: 2,1), tabagismo (OR: 2,2), e pertencente à raça mestiça, que diminuiram o risco de degeneração macular relacionada à idade (OR: 0,40). Consumo de carne vermelha e de peixe, índice de massa corporal e coloração da íris não foram fatores de risco. Idade avançada foi associada com progressão para degeneração macular relacionada à idade mais grave. CONCLUSÃO: Exposição à luz solar, história familiar de degeneração macular relacionada à idade, e idade avançada foram os fatores de risco significativos. Podem existir outras variáveis, já que os riscos não foram bem explicados pelos fatores existentes. Um maior tamanho amostral poderia produzir resultados diferentes e melhores.

Visual acuity and refraction by age for children of three different ethnic groups in Paraguay / Acuidade visual e refração por idade para crianças de três grupos étnicos diferentes no Paraguai

PURPOSE: To characterize refractive errors in Paraguayan children aged 5-16 years and investigate effect of age, gender, and ethnicity. METHODS:The study was conducted at 3 schools that catered to Mennonite, indigenous, and mixed race children. Children were examined for presenting visual acuity, autorefraction with and without cycloplegia, and retinoscopy. Data were analyzed for myopia and hyperopia (SE ≤-1 D or -0.5 D and ≥2 D or ≥3 D) and astigmatism (cylinder ≥1 D). Spherical equivalent (SE) values were calculated from right eye cycloplegic autorefraction data and analyzed using general linear modelling. RESULTS: There were 190, 118, and 168 children of Mennonite, indigenous and mixed race ethnicity, respectively. SE values between right/left eyes were nonsignificant. Mean visual acuity (VA) without correction was better for Mennonites compared to indigenous or mixed race children (right eyes: 0.031, 0.090, and 0.102 logMAR units, respectively; P<0.000001). There were 2 cases of myopia in the Mennonite group (1.2%) and 2 cases in the mixed race group (1.4%) (SE ≤-0.5 D). The prevalence of hyperopia (SE ≥2 D) was 40.6%, 34.2%, and 46.3% for Mennonite, indigenous and mixed race children. Corresponding astigmatism rates were 3.2%, 9.5%, and 12.7%. Females were slightly more hyperopic than males, and the 9-11 years age group was the most hyperopic. Mennonite and mixed race children were more hyperopic than indigenous children. CONCLUSIONS: Paraguayan children were remarkably hyperopic and relatively free of myopia. Differences with regard to gender, age, and ethnicity were small.

OBJETIVO: Caracterizar os erros de refração em crianças paraguaias com idades entre 5 e 16 anos e investigar efeito da idade, gênero e etnia. MÉTODOS: O estudo foi realizado em três escolas que atendiam crianças de etnia Menonita, indígena e mista. As crianças foram examinadas em relação à acuidade visual, autorrefração com e sem cicloplegia, e retinoscopia. Os dados foram analisados ​​para correção de miopia e hipermetropia (EE ≤-1 D ou -0,5D e ≥ 2D ou ≥3 D) e astigmatismo (cilindro ≥1 D). Valores equivalentes esféricos (EE) foram calculados a partir dos dados de autorrefração cicloplegiada do olho direito e analisados ​​por meio de modelagem linear geral. RESULTADOS: Foram avaliadas 190, 118 e 168 crianças de etnias Menonita, indígena e mista, respectivamente. Diferenças entre os valores de EE de olhos direitos e esquerdos não foram significantes. A acuidade visual (AV) sem correção foi melhor para Menonitas em relação às crianças da etnia indígena ou mista (olho direito: 0,031, 0,090 e 0,102 logMAR, respectivamente; P<0,000001). Houve 2 casos de miopia no grupo Menonita (1,2%) e 2 casos no grupo de etnia mista (1,4%) (SE ≤-0,5 D). A prevalência de hipermetropia (SE ≥2 D) foi de 40,6%, 34,2% e 46,3% para as etnias Menonita, indígena e mista. As taxas correspondentes de astigmatismo foram de 3,2%, 9,5% e 12,7%. As mulheres foram ligeiramente mais hipermétropes do que os homens, e o grupo de 9 a 11 anos de idade foi a mais hipermétrope. Crianças da etnia Menonita e mista se mostraram mais hipermétropes do que as crianças indígenas. CONCLUSÕES: As crianças paraguaias são notavelmente hipermétropes e relativamente livres de miopia. Diferenças com relação ao sexo, idade e etnia são pequenas.

Prevalence and causes of blindness in an urban area of Paraguay / Prevalência e causas de cegueira em uma população urbana do Paraguai

PURPOSE: To determine the prevalence and causes of blindness in Piribebuy, Paraguay. METHODS: A population based study was conducted from September to November 2007 in Piribebuy, Paraguay. Based on the city map, seven clusters were randomly selected, containing 22 to 36 squares (423 to 578 houses) each, where all subjects > 40 years old who agreed to participate were included in the study. Presenting vision acuity (VA) was obtained for each eye, with 'E' Snellen charts 6 meters far from the patient with appropriate light. Eyes with VA<20/60 were also tested with the pinhole. Objective and subjective refraction was performed, followed by examination of anterior segment under the slit-lamp, Goldmann applanation tonometry, and pupil dilatation with 0.5% tropicamide plus 0.5% phenylephrine, followed by evaluation of the posterior pole. Best corrected visual acuity was used to classify the patients as follows: blindness was defined as visual acuity of the better eye <20/400, low vision as 20/400

OBJETIVO: Determinar a prevalência e causas de cegueira em Piribebuy, Paraguay. MÉTODOS: Um estudo populational foi conduzido de setembro a novembro de 2007 em Piribebuy, Paraguay. Baseado no mapa da cidade, sete agrupamentos foramaleatoriamente selecionados, contendo 22 a 36 quarteirões (423 a 578 casas) cada, onde todos os indivíduos > 40 anos de idade, que concordaram em participar, foram incluídos no estudo. A acuidade visual (AV) conforme apresentada foi obtida para cada olho, com Tabela de Snellen a 6 metros do paciente, com luz apropriada. Olhos com AV<20/60 também foram testados com orifício estenopeico. Refrações objetiva e subjetiva foram realizadas, seguido de avaliação da câmara anterior sob lâmpada de fenda, tonometria de aplanação de Goldmann e dilatação pupilar com tropicamida a 0.5% e fenilefrina a 0.5%, seguido de avaliação do polo posterior. A melhor acuidade visual corrigida foi usada para classificar os pacientes nos seguintes grupos: cegueira foi definida como acuidade visual do melhor olho <20/400, baixa visão como 20/400

Prevalence and causes of blindness in an urban area of Paraguay.

PURPOSE: To determine the prevalence and causes of blindness in Piribebuy, Paraguay. METHODS: A population based study was conducted from September to November 2007 in Piribebuy, Paraguay. Based on the city map, seven clusters were randomly selected, containing 22 to 36 squares (423 to 578 houses) each, where all subjects > 40 years old who agreed to participate were included in the study. Presenting vision acuity (VA) was obtained for each eye, with 'E' Snellen charts 6 meters far from the patient with appropriate light. Eyes with VA<20/60 were also tested with the pinhole. Objective and subjective refraction was performed, followed by examination of anterior segment under the slit-lamp, Goldmann applanation tonometry, and pupil dilatation with 0.5% tropicamide plus 0.5% phenylephrine, followed by evaluation of the posterior pole. Best corrected visual acuity was used to classify the patients as follows: blindness was defined as visual acuity of the better eye <20/400, low vision as 20/400