Vision screening using a smartphone platform / Triagem visual usando uma plataforma no smartphone

ABSTRACT Objective: The main aim of this study was to evaluate the performance of a platform designed for pediatricians to screen amblyopia using a smartphone. Methods: The medical records of consecutive children who received visual screening using a smartphone platform were retrospectively reviewed. The smartphone was used with a flash concentrator case and a software for capturing images of both eyes simultaneously by a photorefraction mechanism. The platform performance was compared to the comprehensive ophthalmological examination, which is considered the gold standard for detecting amblyopia. Sensitivity, specificity, positive predictive value, and negative predictive value of the software in detecting amblyopia risk factors were calculated. Results: A total of 157 children were included, with a mean age of 6.0±.5 years (range 5-7). In 94% of the cases, the software was able to analyze the images and release a result, determining whether or not the child presented with amblyopia risk factors. Compared to the ophthalmological examination, the smartphone platform sensitivity in detecting amblyopia risk factors was 84%, the specificity was 74%, the positive predictive value was 86%, and the negative predictive value was 70%. Conclusions: The sensitivity and specificity of the smartphone photoscreening platform to detect amblyopia risk factors were within the range of traditional instrument-based vision screening technology. A smartphone photorefraction platform appears to be a promising cost-effective alternative to assist pediatricians and minimize obstacles to vision screening and amblyopia detection. Future studies are needed to gather additional comparative data.

RESUMO Objetivo: Avaliar a performance de uma plataforma desenvolvida para pediatras para triagem de ambliopia utilizando um smartphone. Métodos: Os prontuários consecutivos de crianças submetidas a triagem visual usando uma plataforma no smartphone foram analisados retrospectivamente. Uma capa concentradora de flash foi utilizada no smartphone com um software para capturar imagens simultâneas dos dois olhos por um mecanismo de fotorrefração. A performance da plataforma foi comparada ao exame oftalmológico completo, considerado o padrão ouro para detecção de ambliopia. Foram calculados sensibilidade, especificidade, valor preditivo positivo e valor preditivo negativo do software em detectar fatores de risco para ambliopia. Resultados: Foram incluídas 157 crianças com idade média de 6.0±0.5 anos (variação de 5 a 7 anos). Em 94% dos casos, o software foi capaz de analisar as imagens e fornecer um resultado, determinando se a criança apresentava ou não fatores de risco para ambliopia. Comparados ao exame oftalmológico, a sensibilidade da plataforma no smartphone em detectar fatores de risco para ambliopia foi de 84%, a especificidade foi de 74%, o valor preditivo positivo foi de 86% e o valor preditivo negativo foi de 70%. Conclusões: A plataforma de triagem por fotorrefração usando o smartphone apresentou sensibilidade e especificidade para detectar fatores de risco para ambliopia semelhantes às encontradas em instrumentos tradicionais de triagem por fotorrefração. Uma plataforma no smartphone é uma alternativa custo-efetiva promissora para auxiliar pediatras a minimizar os obstáculos para triagem visual e detecção da ambliopia. Estudos futuros são necessários a fim de reunir dados comparativos adicionais.

Vision for the Future Project: Screening impact on the prevention and treatment of visual impairments in public school children in São Paulo City, Brazil

OBJECTIVES: Uncorrected refractive errors are the leading cause of visual impairment in children. In this cross-sectional retrospective study, we analyzed a social visual screening program for school children in São Paulo, Brazil, evaluated its impact on the prevention and treatment of children's visual disabilities, and assessed its epidemiological outcomes to outline suggestions for its improvement. METHODS: First-grade children from public schools were submitted to prior visual screening by their teachers. Selected children were forwarded to the hospital's campaigns for a second screening by ophthalmologists and treatment if needed. Data were analyzed for age, sex, visual acuity, biomicroscopy, refractive errors, ocular movement disorders, amblyopia, number of donated spectacles, and number of children forwarded to specialized care. RESULTS: A total of 1080 children were included with mean age of 6.24±0.45 years. Children with normal ophthalmological exam, 591 (54.7%; 95% confidence interval [CI]: 51.7%-57.7%) were dismissed and considered false-positives. Myopia, hyperopia, and astigmatism components were found in 164 (15.2%; CI: 13.1%-17.4%), 190 (17.6%; CI: 15.3%-20.0%), and 330 (30.5%; CI: 27.8%-33.4%) children, respectively. Amblyopia was diagnosed in 54 (5%; CI: 3.5%-6.4%) children, and 117 (10.8%; CI: 9.8%-12.8%) presented ocular movement disorders. A total of 420 glasses were donated. CONCLUSION: Epidemiological findings for amblyopia and refractive errors are consistent with those of similar studies. The expressive number of diagnoses performed and number of glasses donated to underprivileged children depict the importance of such projects. New guidelines to improve their cost-effectiveness, such as professional training and community sensitization, are imperative.