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Objective. To review data on functional low vision (FLV) (low vision--visual acuity (VA) < 6/18 (<20/60) to ≥ perception of light (PL+) in the better eye--that is untreatable and uncorrectable) in adults aged 50 years or older from published population-based surveys from 15 countries in Latin America and the Caribbean. Methods. Data from 15 cross-sectional, population-based surveys on blindness and visual impairment (10 national and five subnational) covering 55 643 people ≥ 50 years old in 15 countries from 2003 to 2013 were reanalyzed to extract statistics on FLV. Eleven of the studies used the rapid assessment of avoidable blindness (RAAB) method and four used the rapid assessment of cataract surgical services (RACSS) method. For the 10 national surveys, age-and sex-specific prevalence of FLV was extrapolated against the corresponding population to estimate the total number of people ≥ 50 years old with FLV. Results. Age- and sex-adjusted prevalence of FLV in people ≥ 50 years old ranged from 0.9% (Guatemala, Mexico, and Uruguay) to 2.2% (Brazil and Cuba) and increased by age. The weighted average prevalence for the 10 national surveys was 1.6%: 1.4% in men and 1.8% in women. For all 10 national studies, a total of 509 164 people ≥ 50 years old were estimated to have FLV. Based on the 910 individuals affected, the main causes of FLV were age-related macular degeneration (weighted average prevalence of 26%), glaucoma (23%), diabetic retinopathy (19%), other posterior segment disease (15%), non-trachomatous corneal opacities (7%), and complications after cataract surgery (4%). Conclusions. FLV is expected to rise because of1) the exponential increase of this condition by age, 2) increased life expectancy, and 3) the increase in people ≥ 50 years old. These data can be helpful in planning and developing low vision services for the region; large countries such as Brazil and Mexico would need more studies. Prevention is a major strategy to reduce FLV, as more than 50% of it is preventable. [ABSTRACT FROM AUTHOR]

Objective. Determine the prevalence of blindness and avoidable visual impairment in Argentina, its causes, the coverage of cataract surgery, and the barriers that hinder access to these services. Methods. Cross-sectional population study conducted between May and November 2013 using the standard methodology for rapid assessment of avoidable blindness (RAAB), with a random cluster sampling of 50 people aged 50 years or more, representative of the entire country. Participants' visual acuity (VA) was measured and the lens and posterior pole were examined by direct ophthalmoscopy. An assessment was made of the causes of having VA < 20/60, the coverage and quality of cataract surgery, and the barriers to accessing treatment. Results. 3 770 people were assessed (92.0% of the projected number). The prevalence of blindness was 0.7% (confidence interval of 95%: 0.4-1.0%). Unoperated cataract was the main cause of blindness and severe visual impairment (44.0% and 71.1%, respectively), while the main cause of moderate visual impairment was uncorrected refractive errors (77.8%). Coverage of cataract surgery was of 97.1%, and 82.0% of operated eyes achieved VA ≥20/60. The main barriers to receiving this treatment were fear of the surgical procedure or of a poor result (34.9%), the cost (30.2%), and not having access to the treatment (16.3%). Conclusions. There is a low prevalence of blindness in the studied population and cataract is the main cause of blindness and severe visual impairment. Efforts should continue to extend coverage of cataract surgery, enhance preoperative evaluation, improve calculations of the intraocular lenses that patients need, and correct postoperative refractive errors with greater precision. [ABSTRACT FROM AUTHOR]

Objective. Determine prevalence of blindness and visual impairment in adults aged ≥ 50 years in Panama, identify their main causes, and characterize eye health services. Methods. Cross-sectional population study using standard Rapid Assessment of Avoidable Blindness methodology. Fifty people aged ≥ 50 years were selected from each of 84 clusters chosen through representative random sampling of the entire country . Visual acuity was assessed using a Snellen chart; lens and posterior pole status were assessed by direct ophthalmoscopy. Cataract surgery coverage was calculated and its quality assessed, along with causes of visual acuity < 20/60 and barriers to access to surgical treatment. Results. A total of 4 125 people were examined (98.2% of the calculated sample). Age- and sex-adjusted prevalence of blindness was 3.0% (95% CI: 2.3-3.6). The main cause of blindness was cataract (66.4%), followed by glaucoma (10.2%). Cataract (69.2%) was the main cause of severe visual impairment and uncorrected refractive errors were the main cause of moderate visual impairment (60.7%). Surgical cataract coverage in individuals was 76.3%. Of all eyes operated for cataract, 58.0% achieved visual acuity ≤ 20/60 with available correction. Conclusions. Prevalence of blindness in Panama is in line with average prevalence found in other countries of the Region. This problem can be reduced, since 76.2% of cases of blindness and 85.0% of cases of severe visual impairment result from avoidable causes. [ABSTRACT FROM AUTHOR]

Objectives. To determine the prevalence of blindness and visual impairment in Honduras, its causes and the response by the health services to growing demand. Methods. A cross-sectional population study was conducted between June and December 2013 using the standard methodology of the Rapid Assessment of Avoidable Blindness. A random sample survey was done in 63 clusters of 50 individuals aged ≥ 50, representative of the country as a whole. Visual acuity (VA) was assessed using a Snellen eye chart, and the condition of the lens and posterior pole was examined by direct ophthalmoscopy. Cataract surgical coverage was calculated and an assessment made of its quality, the causes of VA < 20/60 and the barriers to accessing surgical treatment. Results. A total of 2 999 people were examined (95.2% of the forecast total). Blindness prevalence was 1.9% (confidence interval of 95%: 1.4-2.4%) and 82.2% of these cases were avoidable. The main causes of blindness were unoperated cataracts (59.2%) and glaucoma (21.1%). Uncorrected refraction error was the main cause of severe (19.7%) and moderate (58.6%) visual impairment. Cataract surgical coverage was 75.2%. 62.5% of the eyes operated for cataracts achieved a VA > 20/60 with available correction. The main barriers against cataract surgery were cost (27.7%) and the lack of availability or difficulty of geographical access to the treatment (24.6%). Conclusions. The prevalence of blindness and visual impairment in Honduras is similar to that of other Latin American countries. 67% of cases of blindness could be resolved by improving the response capacity of the ophthalmological services, especially of cataract surgery, improving optician services and incorporating eye care in primary health care. [ABSTRACT FROM AUTHOR]

Objective. To estimate the prevalence of blindness and visual impairment among adults in Peru and to determine their causes, to evaluate the coverage and quality of the cataract surgical services and to investigate the barriers that inhibit access to these services. Methods. A cross-sectional population study with two-stage random cluster sampling of individuals of ≥ 50 years old, representative of the entire country, using the standard methodology of the Rapid Assessment of Avoidable Blindness. Visual acuity was assessed and the condition of the lens and posterior pole examined by direct ophthalmoscopy. Cataract surgical coverage was calculated. Its quality, as well as the causes of visual acuity < 20/60 and the barriers to accessing surgical treatment were assessed. Results. A total of 4 849 people were examined. Blindness prevalence was 2.0% (confidence interval of 95%: 1.5-2.5%). The main causes of blindness were cataract (58.0%), glaucoma (13.7%) and age-related macular degeneration (11.5%). Uncorrected refraction errors were the principal cause of moderate visual impairment (67.2%). Cataract surgical coverage was 66.9%. 60.5% of the eyes operated for cataracts achieved a visual acuity ≥ 20/60 with available correction. The main barriers to cataract surgery were the high cost (25.9%) and people being unaware that treatment was possible (23.8%). Conclusions. The prevalence of blindness and visual impairment in Peru is similar to that of other Latin American countries. Given the low cataract surgical coverage and the aging of the population, access to the services could be improved by increasing the population education on eye health and the response capacity of the ophthalmological and cataract surgical services, and by reducing the costs of the latter. [ABSTRACT FROM AUTHOR]

Objectives. To summarize incidence and risk factors for each main cause of visual loss in an African-Caribbean population and discuss the implications of these data from a public health perspective. Methods. A nationally representative cohort (n = 4 709; ages 40-84 years at baseline) had ophthalmic and other examinations over 9 years. Incidence rates were estimated by the product-limit approach. Risk factors were evaluated from Cox regression models. Results. Average incidence was ~ 0.1% per year for blindness (< 6/120) and 0.7% per year for low vision (< 6/18 to 6/120), increasing steeply with age (P < 0.05) and affecting related quality of life (P < 0.05). Age-related cataract and open-angle glaucoma (OAG) accounted for 73.2% of blindness and diabetic retinopathy (DR) for 8.9%; cataract caused two-thirds of low vision. Average incidence was 5.1% per year for all lens changes (gradable/ungradable opacities or aphakia) and 0.4% per year for cataract surgery. Incidence of definite OAG was 0.5% per year (0.9% for suspect or probable); 53% of the affected were unaware. Persons with diabetes mellitus (DM) had a DR incidence of 4.4% per year. Age-related macular degeneration was rare (0.08% per year). Main cataract risk factors were age and DM. OAG incidence increased with age, intraocular pressure, family history, low ocular perfusion pressures, and thinner corneas. DR risk increased with early DM onset, DM duration, oral/insulin treatment, increased systolic and diastolic blood pressures, and hyperglycemia. Antihypertensive treatment halved DR risk. Conclusions. Incidence of visual impairment was high and significantly affected quality of life. Age-related cataract and OAG caused ~ 75% of blindness, indicating the need for public health action to increase appropriate cataract surgery and early OAG detection and treatment. Controlling DM and hypertension would help prevent DR-related complications and could lower cataract risk, further decreasing visual loss. [ABSTRACT FROM AUTHOR]