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Purpose: To determine whether routine monitoring leads to better visual outcomes over time after cataract surgery., Setting: Comprehensive community eyecare center in western India., Design: Comparative case series., Methods: Operative case sheets of all patients having cataract surgery were collected. Preoperative information, surgical details, and follow-up findings were included in the audit. The outcome measure was postoperative corrected distance visual acuity (CDVA), which was graded as good (≥ 6/18), borderline, or poor (<6/60). If the outcome was poor, the causes were classified as follows: selection, surgery, spectacles, or sequelae. The surgeons were briefed about their performance twice a year., Results: The audit included 16,382 cataract surgeries. The proportion of eyes having a CDVA of 6/18 or better 6 weeks postoperatively improved significantly, from 86.5% (95% confidence interval [CI], 84.8%-88.3%) in 2002 to 90.5% (95% CI, 89.3%-91.8%) in 2005, while CDVA worse than 6/60 declined from 5.9% in 2002 to 2.5% in 2005. Manual small-incision cataract surgery was more popular than conventional extracapsular cataract surgery in 2004 and 2005. The incidence of posterior capsule tear and vitreous loss declined in the later years, although the rate of striate keratitis remained the same. Younger patients, women, those without ocular comorbidity, and those with a preoperative CDVA of better than 6/60 had better visual acuity 8 weeks postoperatively., Conclusion: Routine monitoring and modernization of technique helped increase good visual outcomes and reduce poor visual outcomes after cataract surgery., (Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Background: A survey was undertaken in 2007 to assess the prevalence and causes of blindness and visual impairment in people aged ≥ 50 years in three different counties in Jiangxi, South East China (Gao'an, Xin'gan and Wan'zai). The counties were purposively selected to assess the impact of established non-governmental organisation activities in two counties (Gao'an and Xin'gan) compared with a third county (Wan'zai) without such a programme., Methods: Clusters of 50 people aged ≥ 50 years were sampled with a probability proportional to the size of the population. Because of differences in expected prevalence and resources available for conducting the surveys, the total sample size varied from 4699 in Gao'an (94.0% response rate) to 3834 in Xin'gan (95.9%) and 2861 (95.4%) in Wan'zai. Households within clusters were selected through random walk sampling. Visual acuity (VA) was measured with a tumbling 'E' chart. Ophthalmologists examined people with VA< 6/18 in either eye., Results: The prevalence of blindness (VA< 3/60 in the better eye with available correction) was similar in Gao'an (1.5%, 95% CI 1.1% to 1.8%), Xin'gan (1.8%, 1.4% to 2.2%) and Wan'zai (1.6%, 1.2% to 2.1%), and the prevalence of visual impairment (VA< 6/18 and ≥ 6/60) was approximately fourfold higher. Cataract was the leading cause of blindness in each of the three counties, while uncorrected refractive error was the dominant cause of visual impairment. The majority of blindness was avoidable in Gao'an (84.3%), Xin'gan (71.0%) and Wan'zai (71.7%)., Conclusions: The prevalence of blindness in the three counties in Jiangxi, China was lower than expected, yet most of the blindness and visual impairment was avoidable, indicating that the prevalence could be reduced further through adequate programme planning and implementation.

Objective: To estimate the prevalence of blindness in the elderly population of Campinas, Brazil, and to describe the coverage and quality of cataract surgery services in the area., Methods: A brief assessment of cataract surgery services (using the "RACSS" (Rapid Assessment of Cataract Surgical Services Method) was conducted using random cluster sampling, with a sample composed of 60 clusters of 40 people aged 50 years or older. Visual acuity (VA) was measured and the lens status observed by direct visual ophthalmoscopy. From the selected sample of 2,400 subjects, 92.67% were examined., Results: Blindness (VA < 3/60 with available correction) was found in 1.98 % (2.03 % among male subjects, and 1.94 % among female subjects). The prevalence of blindness varied with age, from 0.2%, in the group from 50 to 54 years, to 7.2% in those above 80. Cataract was the main cause of blindness (40.2%) followed by suspected posterior segment disorders (18.2%), diabetic retinopathy (15.9%), and glaucoma (11.4%). The cataract surgical coverage was of 93% (VA < 3/60) and 82.18% when the criterion was VA 6/60 in the best eye. The main reasons the subjects did not receive surgical treatment were: fear of undergoing surgery, 11.1%; lack of awareness about the condition, 16.7%; waiting for maturity, 16.7%; and contraindication to surgery, 44.4%., Conclusion: Cataract is the major cause of blindness in Campinas. Education on eye diseases, their prevention and treatment must become part of the city's public healthcare policies.

Aims: To review recent data on prevalence and causes of blindness and visual impairment in Latin America., Method: Data from recent population-based prevalence surveys in nine countries in Latin America, covering 30,544 people aged 50 years and older, are presented., Results: The prevalence of bilateral blindness (VA <3/60 in the better eye with available correction) ranged from 1.3% in urban Buenos Aires, Argentina, to 4.0% in two rural districts of Peru; low vision from 5.9% in Buenos Aires to 12.5% in rural Guatemala. Cataract was the main cause of blindness (41-87%), followed by posterior segment disease (7-47%). Avoidable blindness ranged from 43% in urban Brazil to 94% in rural Guatemala., Conclusions: 43% to 88% of all blindness in Latin America is curable, being caused by cataract and refractive errors. Simple and cost-effective intervention strategies exist and need to be made available to more people. Also, the visual outcome from cataract surgery can be improved. In the urban areas with adequate eye care services, blindness and low vision due to posterior segment disease are increasing. Results from these surveys may help planners to estimate the prevalence and causes of blindness in their own area or country.

Objectives: To conduct rapid assessments of avoidable blindness to estimate the magnitude and causes of blindness in people aged >/=50 years in Negros Island and Antique district, Philippines., Methods: Clusters of 50 people aged >/=50 years were sampled with probability proportionate to size. Households within clusters were selected through compact segment sampling. Visual acuity (VA) was measured with a tumbling "E" chart. Ophthalmologists examined people with VA<6/18 in either eye., Results: In Negros, 2774 of 3649 enumerated subjects were examined (76.0%) and 3177 of 3842 enumerated subjects in Antique (82.7%). The prevalence of blindness (presenting VA<3/60 in better eye) was 2.6% (95% CI = 2.0 to 3.2%) in Negros and 3.0% (2.4 to 3.6%) in Antique. The leading cause of blindness was untreated cataract, and was refractive error for visual impairment (VA<6/18 to >/=6/60). Most of the cases of blindness (67% in Negros, 82% in Antique) and visual impairment (94% in Negros, 95% in Antique) were avoidable (ie, operated and unoperated cataract, refractive error and corneal scar). In Negros, 23% of eyes had a poor outcome after cataract surgery, and 13% in Antique., Conclusions: The prevalence of blindness in two areas in the Philippines was relatively low. Since most cases were avoidable, further reductions are possible.

Background: The World Health Organization estimates that there were 37 million blind people in 2002 and that the prevalence of blindness was 9% among adults in Africa aged 50 years or older. Recent surveys indicate that this figure may be overestimated, while a survey from southern Sudan suggested that postconflict areas are particularly vulnerable to blindness. The aim of this study was to conduct a Rapid Assessment for Avoidable Blindness to estimate the magnitude and causes of visual impairment in people aged > or = 50 y in the postconflict area of the Western Province of Rwanda, which includes one-quarter of the population of Rwanda., Methods and Findings: Clusters of 50 people aged > or = 50 y were selected through probability proportionate to size sampling. Households within clusters were selected through compact segment sampling. Visual acuity (VA) was measured with a tumbling "E" chart, and those with VA below 6/18 in either eye were examined by an ophthalmologist. The teams examined 2,206 people (response rate 98.0%). The unadjusted prevalence of bilateral blindness was 1.8% (95% confidence interval [CI] 1.2%-2.4%), 1.3% (0.8%-1.7%) for severe visual impairment, and 5.3% (4.2%-6.4%) for visual impairment. Most bilateral blindness (65%) was due to cataract. Overall, the vast majority of cases of blindness (80.0%), severe visual impairment (67.9%), and visual impairment (87.2%) were avoidable (i.e.. due to cataract, refractive error, aphakia, trachoma, or corneal scar). The cataract surgical coverage was moderate; 47% of people with bilateral cataract blindness (VA < 3/60) had undergone surgery. Of the 29 eyes that had undergone cataract surgery, nine (31%) had a best-corrected poor outcome (i.e., VA < 6/60). Extrapolating these estimates to Rwanda's Western Province, among the people aged 50 years or above 2,565 are expected to be blind, 1,824 to have severe visual impairment, and 8,055 to have visual impairment., Conclusions: The prevalence of blindness and visual impairment in this postconflict area in the Western Province of Rwanda was far lower than expected. Most of the cases of blindness and visual impairment remain avoidable, however, suggesting that the implementation of an effective eye care service could reduce the prevalence further.

Aim: To test a method for the rapid assessment of cataract blindness in South Africa., Design: Randomised cluster-based cross-sectional survey (20 clusters of 50 each)., Setting: Pension pay points in Moretele district, North West Province, South Africa., Subjects: Female pensioners aged >or=60 years, and male pensioners aged >or=65 years., Outcome Measures: (1) Prevalence of cataract requiring surgery; (2) prevalence of blindness due to cataract; (3) cataract surgical coverage; (4) cataract surgery outcome; and (5) barriers to cataract surgery., Results: 1000 pensioners were screened (681 women and 319 men). 17.2% of pensioners had operable cataract (visual acuity <6/60); 95% CI -3.4% to 3.4%); 15.6% of pensioners were blind due to cataract (95% CI -3.1% to 3.4%); and 5.6% of pensioners had had previous cataract surgery, 55.4% with intraocular lens implant and 44.6% without intraocular lens implant. The cataract surgical coverage was 24.6%. 80% of people who had had surgery were satisfied with the result, but 26.8% had a poor outcome according to the World Health Organization criteria. The main barrier to uptake of surgery was a lack of awareness of the availability of the surgery., Conclusions: Rapid assessment of cataract at pension pay points is a useful and effective tool for our district Vision 2020 programmes in South Africa. Steps need to be taken to raise awareness of the availability of cataract surgery among indigent pensioners, and to improve the quality of visual outcome after surgery by ensuring routine monitoring of postoperative visual acuity.

Objective: To report on the use of lot quality-assurance sampling (LQAS) surveys undertaken within an area-sampling framework to identify priority areas for intervention with trachoma control activities in Viet Nam., Methods: The LQAS survey method for the rapid assessment of the prevalence of active trachoma was adapted for use in Viet Nam with the aim of classifying individual communes by the prevalence of active trachoma among children in primary school. School-based sampling was used; school sites to be sampled were selected using an area-sampling approach. A total of 719 communes in 41 districts in 18 provinces were surveyed., Findings: Survey staff found the LQAS survey method both simple and rapid to use after initial problems with area-sampling methods were identified and remedied. The method yielded a finer spatial resolution of prevalence than had been previously achieved in Viet Nam using semiquantitative rapid assessment surveys and multistage cluster-sampled surveys., Conclusion: When used with area-sampling techniques, the LQAS survey method has the potential to form the basis of survey instruments that can be used to efficiently target resources for interventions against active trachoma. With additional work, such methods could provide a generally applicable tool for effective programme planning and for the certification of the elimination of trachoma as a blinding disease.

Objective: To determine the prevalence of blindness and of cataract blindness in persons 50 years of age or older in Piura and Tumbes, which are two departments in northern Peru, and to describe the coverage and quality of cataract surgery services in that area, and the barriers that prevent access to those services., Methods: Systematic sampling of persons 50 years old or older was done in Piura and Tumbes between August 2002 and March 2003, with 80 clusters of 60 people each being selected. Of the 4 800 persons chosen, 4,782 of them were examined, using a survey instrument that gathered general information on each person, the results of the visual acuity test and the lens examination, and information on cataract surgery or why that surgery had not been done. Visual acuity (VA) testing was done with a Snellen optotype with the letter "E," with sizes of 20/60 and 20/200 at distances of 6 m and 3 m, respectively, with the person using the visual correction (glasses) available. When the VA was less than 20/60 in one of the eyes, vision was tested with pinhole glasses., Results: The prevalence of bilateral blindness (VA < 20/400) due to cataract, adjusted by age and sex, was 2.1% (95% confidence interval (CI): 1.7% to 2.6%). Among the 193 persons with bilateral blindness due to any cause, cataract was the cause in 104 of them (53.9%). The prevalence of blindness due to cataract or other causes increased with age and was higher in women than in men. Only 25% of the persons studied who needed cataract surgery had had that done. The prevalence of bilateral VA less than 20/200 due to unoperated cataract was 6.3% (95% CI: 5.3% to 7.3%); only 12% of the persons with that level of visual deficiency had had cataract surgery. The VA of 26% of the eyes operated on for cataract was lower than 20/200. The reasons given by persons who needed cataract surgery but who had not had it included not being able to pay for the operation (28%), lack of knowledge concerning cataracts (25%), fear of the operation (23%), and fear of completely losing their sight (17%)., Conclusions: Most of the cases of blindness and of serious deficiency in visual acuity in persons 50 years old or older in Piura and Tumbes are due to uncorrected refractive defects, especially cataracts. The high prevalence of bilateral blindness due to cataracts (2.1%) could be reduced with measures that facilitate access to appropriate treatment.

Objective: To test the applicability of lot quality assurance sampling (LQAS) for the rapid assessment of the prevalence of active trachoma., Methods: Prevalence of active trachoma in six communities was found by examining all children aged 2-5 years. Trial surveys were conducted in these communities. A sampling plan appropriate for classifying communities with prevalences < or =20% and > or =40% was applied to the survey data. Operating characteristic and average sample number curves were plotted, and screening test indices were calculated. The ability of LQAS to provide a three-class classification system was investigated., Findings: Ninety-six trial surveys were conducted. All communities with prevalences < or =20% and > or =40% were identified correctly. The method discriminated between communities with prevalences < or =30% and >30%, with sensitivity of 98% (95% confidence interval (CI)=88.2-99.9%), specificity of 84.4% (CI=69.9-93.0%), positive predictive value of 87.7% (CI=75.7-94.5%), negative predictive value of 97.4% (CI=84.9-99.9%), and accuracy of 91.7% (CI=83.8-96.1%). Agreement between the three prevalence classes and survey classifications was 84.4% (CI=75.2-90.7%). The time needed to complete the surveys was consistent with the need to complete a survey in one day., Conclusion: Lot quality assurance sampling provides a method of classifying communities according to the prevalence of active trachoma. It merits serious consideration as a replacement for the assessment of the prevalence of active trachoma with the currently used trachoma rapid assessment method. It may be extended to provide a multi-class classification method.