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Aims: To estimate the magnitude and causes of blindness in people aged >50 years in Satkhira district, Bangladesh, and to assess the availability of cataract surgical services. Methods: 106 clusters of 50 people aged >50 years were selected by probability-proportionate to size sampling. Households were selected by compact segment sampling. Eligible participants had their visual acuity measured. Those with visual acuity ,6/18 were examined by an ophthalmologist. A needs assessment of surgical services was conducted by interviewing service providers. Results: 4868 people were examined (response rate 91.9%). The prevalence of bilateral blindness was 2.9% (95% confidence interval (CI) 2.4% to 3.5%), that of severe visual impairment was 1.6% (95% CI 1.2% to 2.0%) and that of visual impairment was 8.4% (95% CI 7.5% to 9.3%). 79% of bilateral blindness was due to cataract. The cataract surgical coverage was moderate; 61% of people with bilateral cataract blindness (visual acuity ,3/60) had undergone surgery. 20% of the 213 eyes that had undergone cataract surgery had a best-corrected poor outcome (visual acuity ,6/60). The cataract surgical rate (CSR) in Satkhira was 547 cataract surgeries per million people per year. Conclusions: Although the prevalence of blindness and visual impairment was lower than expected, the CSR is inadequate to meet the existing need, and the quality of surgery needs to be improved.

BackgroundData on prevalence and causes of avoidable blindness in Malawi are not readily available. The purpose of this study was to determine the prevalence and causes of blindness in persons aged 50 and above in southern Malawi to plan eye care services for the community.MethodologyA population-based survey was conducted in 7 districts in southern Malawi. Villages were selected by probability proportionate to size within each district. Clusters were further subdivided into segments. A predetermined number of segments were selected randomly in each cluster. The survey team moved from house to house in each segment until they had examined 50 people over the age of 50. Examination consisted of visual acuity measurement with tumbling “E” chart and ocular examination by an ophthalmologist. Participants were categorized by visual acuity. Those who were visually impaired (VA<6/18 in the better eye with available correction) were assigned a main cause of visual loss. Further information was sought from anyone who had received cataract surgery.ResultsA total number of 3,583 persons aged 50 and above were sampled; among these 3,430 (95.7%) were examined. The prevalence of blindness (presenting visual acuity <3/60 in the better eye) among persons aged 50 and above was 3.3% (95% CI 2.5–4.1). Cataract was the most common cause of blindness contributing to 48.2% of all cases, followed by glaucoma (15.8%) and cornea scarring (12.3%). The cataract surgical coverage in blind persons was 44.6%.ConclusionThe prevalence of blindness and visual impairment in persons aged 50 and above was lower than the WHO estimate for Malawi. The majority of the causes were avoidable, with cataract accounting for approximately half of all cases of blindness. The data suggests that expansion of eye care programs to address avoidable causes of blindness is necessary in this area of southern Malawi.

Cataract is the leading cause of blindness globally and surgery is the only known measure to deal with it effectively. Providing high quality cataract surgical services is critical if patients with cataract are to have their sight restored. A key focus of surgery is the outcome of the procedure. In cataract surgery this is measured predominantly, using visual acuity. Population- and hospital-based studies have revealed that the visual outcome of cataract surgery in many low and middle income settings is frequently sub-optimal, often failing to reach the recommended standards set by the World Health Organization (WHO). Another way of measuring outcome of cataract surgery is to ask patients for their views on whether surgery has changed the functioning of their eyes and their quality of life. There are different tools available to capture patient views and now, these patient-reported outcomes are becoming more widely used. This paper discusses the visual outcome of cataract surgery and frames the outcome of surgery within the context of the surgical service, suggesting that the process and outcome of care cannot be separated. It also discusses the components of patient-reported outcome tools and describes some available tools in more detail. Finally, it describes a hierarchy of challenges that need to be addressed before a high quality cataract surgical service can be achieved.