Blindness and visual impairment in Central Europe

AIMS To describe the causes of bilateral and unilateral blindness and visual impairment in two cross-sections of an older Australian population 6 years apart. METHODS The Blue Mountains Eye Study examined 3654 persons aged 49-97 years during 1992-1994 (population cross-section 1). Cohort survivors (2335) and 1174 persons who moved to the area or reached an eligible age were examined during 1997-2000, a total of 3509 persons (population cross-section 2). LogMAR visual acuity was measured after standardized refraction. Blindness and visual impairment were respectively defined by visual acuity <6/60 and <6/12. Causes were determined for the two temporal cross-sections. RESULTS Age-related macular degeneration (AMD) was the principal cause of bilateral and unilateral non-correctable blindness in both cross-sections. AMD caused 77% of bilateral blindness in Cross-section 1 and 50% in Cross-section 2. Cataract, glaucoma, corneal and neurological disease were next equally frequent causes (6% each) of bilateral blindness in Cross-section 1. In Cross-section 2, cataract ranked as the third most frequent principal cause (10%) after other retinal diseases (40%). The proportion of unilateral blindness with AMD as principal cause was very similar (around one-third of cases) in the two cross-sections; while in Cross-section 2 blindness was less frequently caused by cataract (19% vs. 13%). Cataract was the principal cause of both bilateral and unilateral visual impairment, responsible for 50% of bilateral (better eye) and 35-40% of unilateral (worse eye) impairment, with slightly lower rates found in Cross-section 2 than in Cross-section 1. AMD was consistently the second most frequent cause, causing one-third of bilateral and one-fifth of unilateral visual impairment. CONCLUSIONS These data indicate a relative stable pattern of causes for blindness and visual impairment, with AMD and cataract, respectively, dominating these two levels.

To assess prevalence of mild vision impairment (MVI; best corrected visual acuity (BCVA) < 6/12 to 6/18 in the better eye), moderate-to-severe vision impairment (MSVI; BCVA < 6/18 but ≥ 3/60) and blindness (BCVA < 3/60) in a local population in Russia, we conducted the population-based Ural Eye and Medical Study. Out of 7,328 eligible individuals aged 40 + years, 5,899 (80.5%) individuals participated. MVI was present in 184 (3.1%; 95% confidence interval (CI) 2.7, 3.6) individuals, MSVI in 182 (3.1%; 95% CI 2.7, 3.5) individuals, and 11 individuals (0.19%; 95% CI 0.008, 0.30) were blind. Causes for MSVI were cataract (n = 109; 59.9%), late stage of age-related macular degeneration (n = 14; 7.7%; geographic atrophy and neovascular AMD in 7 (3.8%) individuals) each), myopic maculopathy (n = 11; 6.0%), glaucoma (n = 9; 4.9%), non-glaucomatous optic nerve damage (n = 5; 2.7%), and diabetic retinopathy (n = 4; 2.2%). Causes for blindness were cataract (n = 3; 27.3%), myopic maculopathy (n = 2; 18.2%), retinal dystrophies (n = 2; 18.2%), glaucoma (n = 1; 9.1%), and corneal scars (n = 1; 9.1%). Higher prevalence of MSVI/blindness was associated with age (P < 0.001; odds ratio (OR)1.10; 95% CI 1.08, 1.12), male gender (P < 0.001; OR 2.32; 95% CI 1.47, 3.66), educational level (P < 0.001; OR 0.83; 95% CI 0.76,0.92), manual grip force (P < 0.001; OR 0.94; 95% CI 0.92, 0.96), diabetes prevalence (P = 0.006; OR 1.67; 95% CI 1.08, 2.56) and axial length (P < 0.001; OR 1.43; 95% CI 1.26,1.62). In this population from Bashkortostan/Russia, prevalence of MVI, MSVI and blindness was 3.1%, 3.1% and 0.19%, respectively. Cataract was the most frequent cause of reversible vision impairment, while AMD, myopic maculopathy and glaucoma were the most common reasons for irreversible vision impairment.

To investigate the prevalence and causes of visual impairment in elderly Amis aborigines in Eastern Taiwan. Population-based cross-sectional study of visual impairment of elderly Amis (65 years of age or older). We conducted ocular examinations on 2,316 participants, which represent 61.2 % of the elderly population. We used WHO criteria to identify visual impaired subjects, and the causes were analyzed. Ninety-four subjects were identified with low vision and nineteen were blind. The prevalence of low vision was 4.06 % (95 % confidence interval, 3.26, 4.56 %); that of blindness was 0.82 % (95 % confidence interval, 0.45, 1.19 %). Cataracts (47.79 %) were the main cause of visual impairment, followed by age-related macular degeneration (15.93 %), corneal opacity (7.96 %), optic neuropathy (7.96 %), diabetic retinopathy (5.31 %), and retinitis pigmentosa (2.65 %). Glaucoma was a minor cause of visual impairment. There were no significant gender differences in the prevalence and specific causes of visual impairment. The prevalence of treatable causes of vision impairment, for example cataracts and corneal opacity, is high among the elderly Amis aborigines. They would, therefore, benefit from a more aggressive and in-depth eye-care program as a blindness-prevention strategy.

PURPOSE We sought to estimate the prevalence of visual impairment among an elderly population in urban Taiwan, determine the causes of visual impairment, and gain information about certain socioeconomic factors associated with visual impairment.METHODS A population-based survey of ocular diseases in residents aged 50 years or older was conducted in Peitou Precinct, Taipei, Taiwan. All participants underwent a comprehensive ophthalmic examination, including visual acuity measurement, using standardized protocols. Demographic data, marital status, employment status, and educational level were gathered through an interview.RESULTS A total of 2034 participants completed the visual acuity measurements. The prevalence of visual impairment (defined as best-corrected visual acuity in the better eye <6/18) among this population was 2.75% (95% confidence intervals: 2.04%–3.46%). Three major causes of visual impairment were cataract (30.4%), high myopic macular degeneration (25.0%), and age-related macular degeneration (14.3%). In multivariate analysis, age was positively correlated with visual impairment (P < 0.001), and higher education level was associated with a significant decrease in the odds of being visually impaired (P < 0.001). No relation was found between visual impairment and sex, or marital and employment status.CONCLUSIONS This study provides the first information about the prevalence and causes of visual impairment in Taiwan, and identifies age and educational level as the most important factors related to visual impairment. Additional educational programs should be developed to improve individual awareness of age-related ocular diseases and the availability of current ophthalmic intervention.

To determine the causes of childhood blindness and severe visual impairment (BL/SVI) in schools for the blind in Malaysia. All children ≤ 15 years attending 24 schools for the blind throughout the country were examined using the WHO Prevention of Blindness Programme (WHO/PBL) eye examination record for children, and visual loss was classified according to the International Classification of Disease (ICD). In all, 469 children were examined, of whom 448 (95.6%) had BL/SVI. The major causes of visual loss were retinal disorders (n=148, 33%; mainly retinopathy of prematurity (n=78, 17.4%)), cataract/pseudophakia/aphakia (n=77, 17.2%), and anomalies affecting the whole globe. (n=86, 19.2%). The major underlying etiology was undetermined (n = 193, 43.1%), followed by hereditary factors, 21.7% (mainly retinal dystrophies), and perinatal factors, 20.5%. More than 34 (7.6%) cases were considered potentially preventable and 192 (42.9%) potentially treatable. Diseases of the retina are the major cause of visual impairment, with retinopathy of prematurity being an important avoidable cause. This reflects expansion of neonatal services in Malaysia, and improved survival of very low birth weight and preterm babies. Lens-related causes of visual impairment reflect the need to further improve pediatric ophthalmology services in Malaysia.

1. Luis H. Ospina, MD* 1. *Assistant Professor, Pediatric Ophthalmology and Neuro-ophthalmology, Ste-Justine Hospital, University de Montreal, Montreal, Quebec, Canada After completing this article, readers should be able to: 1. Recognize cortical visual impairment (CVI) as an important cause of pediatric visual loss. 2. Identify the most frequent causes of pediatric CVI and, more specifically, understand the role of hypoxia as a cause of central visual damage. 3. Describe the different patterns and implications for future vision of hypoxic central visual damage occurring in preterm compared with term babies. 4. Know the clinical signs suggestive of CVI in children. 5. Discuss the involvement of visual functions other than visual acuity (ie, cognitive visual aspects) in CVI and correlate them with the likely affected neuroanatomic substrates. 6. Explain the value of using a multidisciplinary approach in rehabilitating children who have CVI early in their development. Vision loss caused by central nervous system damage often is referred to as CVI but also may be referred to as cerebral visual impairment or neurologic visual impairment. These terms refer to the fact that the primary defect may not necessarily be limited to the striate (primary visual) cortex and may affect other areas subserving vision, such as the visual associative cortex, optic radiations, and visual attention pathways. Although it is not yet certain which of these three terms best describes the visual deficit, it is clear that use of the label cortical blindness must be abandoned. That term not only evokes negative connotations for the child and the family but is inaccurate because in almost every instance, some degree of residual vision remains, and visual improvement can occur. CVI has become the greatest cause of pediatric visual impairment in developed countries (1)(2)(3)(4)(5) and is becoming increasingly prevalent in developing nations. CVI is a problem of increasing frequency for two primary reasons. First, the progress in neonatal care has resulted in improved survival of …

Background:Aging is not a disease; rather, it is a process. As people age, visual impairment (VI) becomes more common. In 2010, the overall prevalence rate of vision impairment in all races was 25.66% in individuals aged ≥ 80 years, according to the estimate of the National Eye Institute at the National Institutes of Health. This review aimed to address the common causes of VI in the elderly.Methods: In this narrative review, an electronic search of the PubMed/MEDLINE database was conducted using “visual impairment” and “elderly” for the period between January 2010 and April 2021, to include randomized clinical trials and observational studies concerning VI in the elderly. The selected time period was chosen to provide an updated review. Results:The search yielded 2955 articles published over the period of more than 11 years. The relevant randomized clinical trials or observational studies were included and reviewed. Cataracts, refractive errors, open-angle glaucoma, age-related macular degeneration, and diabetic retinopathy were the most common age-related ocular disorders leading to VI if untreated in the elderly. The loss of visual acuity can adversely affect quality of life in the elderly. Difficulty with activities of daily living related to VI can lead to social isolation, depression, and anxiety. Loss of vision in the elderly is linked to an increased risk of falls, hip fracture, depression, and poor quality of life. Conclusions:The most common causes of VI in the elderly are cataracts and refractive errors. VI in most ocular diseases is more prevalent in women than in men due to longer lifespan. The overall prevalence of the main causes of VI in the elderly is expected to increase; therefore, health policymakers should consider this when planning for the health-enhancement program of the population.

Visual Consequences of Refractive Errors in the General Population

BackgroundLow vision, along with cataract, trachoma, onchocerciasis, childhood blindness and refractive error, is one of the priorities in the global initiative, VISION 2020-The Right to Sight. The purpose of this study was to characterize the traits of patients presenting at a low vision clinic in China.MethodsA retrospective study was conducted of the records of 299 patients who visited the Low Vision Clinic of Eye and ENT Hospital Affiliated to Fudan University from January 2009 to May 2014. Reviewed parameters included age, gender, education, occupation, cause of visual impairment and types of low vision aids (LVAs) dispensed.ResultsOf all the patients (193 male; aged from 3 to 96 years, with a mean of 29.74 ± 25.23 years), 43.48% experienced moderate visual impairment, 25.42% had severe visual impairment and 21.07% were blind. The four major causes of visual impairment were congenital cataract (14.38%), degenerative myopia (13.71%), juvenile macular degeneration (9.36%) and retinitis pigmentosa (9.36%). The most common causes of visual impairment were congenital cataract (22.67%) in 0-19-year-olds, retinitis pigmentosa (20.62%) in 20-59-year-olds, and age-related macular degeneration (36.54%) in the 60+ group. With the help of LVAs, a significant improvement of distance and/or near vision or visual field was observed in 243 patients, of whom 185 accepted LVAs and 58 patients refused due to high price, inconvenience, young age (≤6 y), clumsy appearance and ignorance. The most commonly dispensed LVAs were stand magnifiers (21.57%) followed by spectacle-type LVAs (19.21%).ConclusionsThe majority of the patients in our low vision clinic were young, the main causes of visual impairment were congenital and hereditary diseases. Stand magnifiers were the most commonly dispensed LVAs. High price was the major reason for refusing LVAs.

Refractive error is one of the major causes of blindness and visual impairment in children; but community based studies are scarce especially in rural parts of Ethiopia. So, this study aims to assess the prevalence of refractive error and its magnitude as a cause of visual impairment among school-age children of rural community. This community-based cross-sectional descriptive study was conducted from March 1 to April 30, 2009 in rural villages of Goro district of Gurage Zone, found south west of Addis Ababa, the capital of Ethiopia. A multistage cluster sampling method was used with simple random selection of representative villages in the district. Chi-Square and t-tests were used in the data analysis. A total of 570 school-age children (age 7-15) were evaluated, 54% boys and 46% girls. The prevalence of refractive error was 3.5% (myopia 2.6% and hyperopia 0.9%). Refractive error was the major cause of visual impairment accounting for 54% of all causes in the study group. No child was found wearing corrective spectacles during the study period. Refractive error was the commonest cause of visual impairment in children of the district, but no measures were taken to reduce the burden in the community. So, large scale community level screening for refractive error should be conducted and integrated with regular school eye screening programs. Effective strategies need to be devised to provide low cost corrective spectacles in the rural community.

Objective: To determine the common causes of visual impairment (VI) and blindness among attendees of a free community outreach program in Edo Central and Edo North Senatorial zones of Edo State. Methods: This report presents the findings from a free community outreach program conducted in the Edo Central and North Senatorial Zones. The participants were residents of these senatorial zones who attended the free ophthalmic outreach events organized between February and July 2022. Results: Four hundred and eighty-two people participated in the outreach events, which were conducted in four different locations across the two senatorial zones. There were 234 participants from the Edo Central senatorial zone and 248 participants from the Edo North senatorial zone. In the Edo Central senatorial zone, 46.2% were either visually impaired (moderate VI = 27.4%, severe VI = 4.7%) or blind (14.1%). In the Edo North senatorial zone, the prevalence of moderate and severe VI was 35% and 2% respectively, while the prevalence of blindness was 12.5%. Cataract was the leading cause of moderate, severe VI, and blindness (55%, 75%, and 64.1%), respectively, across both zones. Whilst refractive error was the second most common cause of moderate VI, and glaucoma was the second most common cause of blindness. Conclusion: The primary causes of VI and blindness in the Edo Central and North Senatorial zones are cataract, glaucoma, and refractive error. Strategies targeting these causes of blindness by promoting awareness and improving access to the available eye care services are recommended.

To estimate the prevalence of cataract, glaucoma, age-related maculopathy (ARM) and diabetic retinopathy (DR) in the adult Finnish population. A representative cross-sectional sample of the Finnish population aged 30 years and older. Of the 7979 eligible people, 7413 (93%) were interviewed and/or examined. The interview included self-reported doctor-made diagnoses of cataract, glaucoma, degenerative fundus changes (mainly ARM) or DR. Information on self-reported eye diseases was complemented with data from national registers, and case records were gathered for non-participants and persons with visual acuity (VA) < 0.5 or reporting difficulties in vision or eye diseases without assessed VA. Based on self-reported and/or register-based data the estimated total prevalences of cataract, glaucoma, ARM and DR in the study population were 10%, 5%, 4% and 1%, respectively. All these chronic eye diseases increased with age (p < 0.001). The corresponding prevalences for persons aged 65 and older were 34%, 13%, 12% and 2%, respectively. Cataract and glaucoma were more common in women than in men [odds ratio (OR) 1.55, 95% confidence interval (CI) 1.26-1.91; OR 1.57, 95% CI 1.24-1.98, respectively]. The most prevalent eye diseases in people with visual impairment (VA < or = 0.25) were ARM (37%), unoperated cataract (27%), glaucoma (22%) and DR (7%). The high prevalence of these mainly age-related eye diseases, together with increasing life expectancy, mean that continuous efforts are needed to identify and treat eye diseases in order to maintain patients' quality of life and to alleviate the social and economic burden of serious eye diseases.

To describe the age-specific prevalence of common eye diseases causing bilateral visual impairment and estimate the total number of Australians with cause-specific visual impairment. Cluster-stratified random sample of 5147 residents aged 40 years and older from urban and rural areas and aged-care facilities. Participants completed a standardized interview and eye examination. Four levels of bilateral visual impairment were defined: less than 20/40 to 20/60 and/or homonymous hemianopia (mild), less than 20/60 to 20/200 or better and/or less than 20 degrees to 10 degrees radius field (moderate), less than 20/200 to 10/200 and/or less than 10 degrees to 5 degrees radius field (severe), and less than 1O/ 200 and/or less than 50 radius field (profound). The major cause of vision loss was identified for all participants found to be visually impaired. Uncorrected refractive error was the most common cause of bilateral visual impairment across all decades of life, rising from 0.5% in 40- to 49-year-olds to 13% among those aged 80 years and older. Prevalence of visual impairment due to diabetic retinopathy was 0.7% in 50- to 59-year-olds and 0.8% in those older than 80 years. Visual impairment due to glaucoma had a prevalence of 0.7% among 60-year-olds and rose to 4% of those older than 90 years. The prevalence of visual impairment due to cataract (only present in those aged 70 years or older) rose from 0.6% to 11% in those older than 90 years, and the prevalence of visual impairment due to age-related macular degeneration rose from 0.8% to 16% in those older than 90 years. The predominant causes of visual impairment change with age. Recognition of these patterns is fundamental for early diagnosis and treatment of eye disease and, where appropriate, referral for rehabilitation.

Purpose:This was a population-based study to determine the prevalence and causes of visual impairment in children less than 16 years in Urban North India.Methods:This cross-sectional study was conducted in 40 clusters of urban Delhi. 20,955 children aged less than 16 years underwent visual acuity screening using age-appropriate visual acuity charts. Unaided visual acuity of enumerated children aged over 2 years was assessed by using Lea symbols chart in 3-5 years age group and logMAR tumbling E charts for the 6-15 years age group. For children aged 0-2 years, fixation and following to torch light was assessed. All the children with unaided visual acuity of <6/12 in any eye in age group 3–15 years and inability to follow the light in age <3 years were referred for detailed ophthalmic examination.Results:Amongst 20,955 children examined for visual acuity a total of 789 children were referred to the central clinic for detailed ophthalmic examination. Of these referred children, a total of 124 had presenting visual acuity <6/18 in the better eye. The prevalence of visual impairment (VI) was 5.92 per thousand (95% CI: 4.96-7.05). The prevalence of moderate to severe visual impairment was maximum in the age group of 11 to 15 years. The main cause of avoidable VI in these children was a refractive error (75.7%). The prevalence of blindness was 0.42 per thousand.Conclusion:Optic nerve abnormalities were the most important cause of blindness in children. Refractive error is the most important cause of visual impairment amongst children and needs to be addressed.

BackgroundCataract, glaucoma and age-related macular degeneration (AMD) are major causes of visual impairment. As these are age-related conditions, the prevalence of associated visual impairment is anticipated to increase as the...