To determine the avoidable causes of childhood blindness in Malaysia and to compare this to other middle income countries, low income countries and high income countries. Data were obtained from a school of the blind study by Patel et al. and analysed for avoidable causes of childhood blindness. Six other studies with previously published data on childhood blindness in Bangladesh, Ethiopia, Nigeria, Indonesia, China and the United Kingdom were reviewed for avoidable causes. Comparisons of data and limitations of the studies are described. Prevalence of avoidable causes of childhood blindness in Malaysia is 50.5 % of all the cases of childhood blindness, whilst in the poor income countries such as Bangladesh, Ethiopia, Nigeria and Indonesia, the prevalence was in excess of 60 %. China had a low prevalence, but this is largely due to the fact that most schools were urban, and thus did not represent the situation of the country. High income countries had the lowest prevalence of avoidable childhood blindness. In middle income countries, such as Malaysia, cataract and retinopathy of prematurity are the main causes of avoidable childhood blindness. Low income countries continue to struggle with infections such as measles and nutritional deficiencies, such as vitamin A, both of which are the main contributors to childhood blindness. In high income countries, such as the United Kingdom, these problems are almost non-existent.
A national study was conducted in children attending six schools for the blind in Malaysia to identify the anatomical site and underlying causes of blindness (BL) and severe visual impairment (SVI), with a view to determine the potentially preventable and treatable causes so that appropriate control measures can be implemented in the future. The standardized clinical examination of eyes was performed and the findings were recorded on the WHO Prevention of Blindness Programme eye examination record form for children with blindness and low vision. A total of 358 children aged between 7 and 17 years were examined, of whom 332 (92.7%) were blind or severely visually impaired. The results relate to these 332 children. Lens was the major anatomical site (22.3%) of visual loss followed by retina (20.8%), whole globe (17.2%), cornea (15.1%), optic nerve (8.7%) and uvea (5.1%). Glaucoma was responsible for BL/SVI in 7.2% and others in 3.6% of cases. Hereditary diseases were responsible for visual loss in 29.5%, intrauterine factors in 4.5%, perinatal factors in 9% and childhood factors in 7.8% of cases. However, the aetiology was unknown in 49.1% of cases which included congenital anomalies of the globe. Childhood cataract and corneal scarring are major treatable causes of BL/SVI that can benefit from future intervention strategies. Perinatal screening for intrauterine factors and hereditary eye diseases, and appropriate interventional therapy will help in reducing the prevalence of childhood blindness.