Uncorrected Refractive Error

The Prevalence of Refractive Error and Visual Impairment Caused by Uncorrected Refractive Error in China

This dissertation, "The Prevalence of Refractive Error and Visual Impairment Caused by Uncorrected Refractive Error in China" by Siu-chun, Danny, Ng, 吳兆駿, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Purpose: WHO reports 46% of world vision impairment from refractive error (RE) among children occurs in China. We estimated RE prevalence and associated vision impairment (VI) among Chinese children and adults. Methods: Data from population-based studies were stratified by gender in age intervals of 3 years (ages 3-17 y) or 10 years (ages >= 30 y): counts of persons with myopia (worse eye spherical equivalent vision ((the cutoff improving to above the cutoff with refraction, and those with myopic retinopathy. Estimates for ages 18-29 y were obtained from regression models derived from the pooled estimates. Prevalence of myopia and VI attributable to RE in each age/gender category was calculated by applying modeled rates to 2000 China census figures and projections for 2020. Association with VI attributable to RE was tested for: gender, urban versus rural residence, and residence in provinces with per capita GDP in the upper versus lower 50% for China. Results: Data were obtained from 5 cohorts for children and 14 for adults. There were 291 million and 21.4 million persons with myopia 2000, expected to rise to 306 million and 36.9 million by 2020. Of these, 18.4 million were blind and 116 million had low vision in 2000, with figures of 25.3 million and 123 million in 2020. Children accounted for the following proportion of RE disease burden in China in 2000: myopia 14.1%. Refractive error was responsible for 82.3% of blindness and 90.5% of low vision among children, and 11.6% and 64.4% of blindness and low vision among adults. Urban residence (OR 1.85, P = 0.004) and higher GDP (OR 10.6, P with refractive blindness among children. For adults, lower GDP was associated with refractive blindness (OR 1.47, P = 0.01). Gender was un-associated with refractive blindness among children or adults. Conclusions: Both children and adults suffer a heavy burden of VI associated with RE in China. Income may affect risk for such VI differently among children and adults. DOI: 10.5353/th_b4804331 Subjects: Eye - Refractive errors - China Vision disorders - China

The Prevalence of Refractive Error and Visual Impairment Caused by Uncorrected Refractive Error in China

Myopia: Animal Models To Clinical Trials

Myopia is the most common optical disorder in the world, and is on the rise in many countries, particularly in East Asia. The impact of myopia is evident as the driving force in the development of refractive surgery and of the spectacle and contact lens industries. While myopia is often seen as a childhood disease that involves complex genetic-environmental factors, it is also a major cause of adult blindness. In Singapore (where myopia has reached one of the highest rates in the world) as well as in Taiwan, Japan and Hong Kong, affected patients have greater severity of myopia, leading to additional secondary complications such as glaucoma.This book provides a comprehensive coverage of all aspects of myopia. It is aimed at ophthalmologists, optometrists, opticians, scientists and pharmaceutical companies. The topics are uniquely treated in that they cover research at the laboratory bench as well as clinical applications and population-based approaches in epidemiology.