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Middle East African Journal of... 2014Childhood blindness and visual impairment (CBVI) are major disabilities that compromise the normal development of children. Health resources and practices to prevent... (Review)
Review
Childhood blindness and visual impairment (CBVI) are major disabilities that compromise the normal development of children. Health resources and practices to prevent CBVI are suboptimal in most countries in the Eastern Mediterranean Region (EMR). We reviewed the magnitude and the etiologies of childhood visual disabilities based on the estimates using socioeconomic proxy indicators such as gross domestic product (GDP) per capita and <5-year mortality rates. The result of these findings will facilitate novel concepts in addressing and developing services to effectively reduce CBVI in this region. The current study determined the rates of bilateral blindness (defined as Best corrected visual acuity(BCVA)) less than 3/60 in the better eye or a visual field of 10° surrounding central fixation) and functional low vision (FLV) (visual impairment for which no treatment or refractive correction can improve the vision up to >6/18 in a better eye) in children <15 years old. We used the 2011 population projections, <5-year mortality rates and GDP per capita of 23 countries (collectively grouped as EMR). Based on the GDP, we divided the countries into three groups; high, middle- and low-income nations. By applying the bilateral blindness and FLV rates to high, middle- and low-income countries from the global literature to the population of children <15 years, we estimated that there could be 238,500 children with bilateral blindness (rate 1.2/1,000) in the region. In addition, there could be approximately 417,725 children with FLV (rate of 2.1/1,000) in the region. The causes of visual disability in the three groups are also discussed based on the available data. As our estimates are based on hospital and blind school studies in the past, they could have serious limitations for projecting the present magnitude and causes of visual disabilities in children of EMR. An effective approach to eye health care and screening for children within primary health care and with the available resources are discussed. The objectives, strategies, and operating procedures for child eye-care are presented. Variables impacting proper screening are discussed. To reach the targets, we recommend urgent implementation of new approaches to low vision and rehabilitation of children.
Topics: Adolescent; Age Distribution; Blindness; Child; Child, Preschool; Female; Humans; Infant; Male; Mediterranean Region; Prevalence; Vision, Low; Visual Acuity; Visually Impaired Persons
PubMed: 25371641
DOI: 10.4103/0974-9233.142273 -
Nature Aging Nov 2022Vision impairment and blindness are strongly associated with aging and late-life disability. While home to about 17% of the world's population, an estimated 25% of...
Vision impairment and blindness are strongly associated with aging and late-life disability. While home to about 17% of the world's population, an estimated 25% of visually impaired people globally live in India. This proportion is expected to increase as India's population rapidly ages and continues to grow. There is a need for up-to-date epidemiologic data on the prevalence of vision impairment and blindness in India and on the socioeconomic determinants of poor vision, especially among older adults, to promote visual and overall health and well-being in later life. This paper uses newly available data from Wave 1 (2017-2019) of the population-based Longitudinal Ageing Study in India to estimate the overall and sex-specific prevalence of presenting visual acuity impairment and blindness among individuals aged 45 and older at the national level and for all constituent states and union territories. Overall, 33.8% (95% confidence interval: 33.31%, 34.26%) of the Indian population aged 45 and older had distance visual acuity impairment or was blind (visual acuity in the better-seeing eye < 20/40). The age-standardized prevalence varied considerably among states (22.3-54.6%), and women were more likely than men to be visually impaired or blind in all states. Near visual acuity impairment was also highly prevalent (43.0%, 95% confidence interval: 42.45%, 43.46%). Vision impairment and blindness were more common among marginalized groups and were associated with lower socioeconomic status. Findings from this study are relevant for surveillance of vision health, design of targeted eye care policies and programs and efforts to promote human and economic development.
Topics: Aged; Female; Humans; Male; Aging; Blindness; India; Prevalence; Vision, Low; Visually Impaired Persons; Middle Aged
PubMed: 37118083
DOI: 10.1038/s43587-022-00298-6 -
Trends in Amplification Dec 2007This article provides an overview of some of the problems and possible solutions surrounding the neglected issue of combined vision and hearing deficits. The subject is... (Review)
Review
This article provides an overview of some of the problems and possible solutions surrounding the neglected issue of combined vision and hearing deficits. The subject is treated by considering each subpopulation, ranging from those who have no residual vision or hearing to those with mild coexisting vision and hearing losses. An attempt is made to relate the different types of visual deficit to the likely problems encountered in real-life activities, such as communication and travel, among individuals who also have a hearing impairment. The assessment and appropriate referral of patients with these combined deficits is discussed, including the interpretation of visual test results and the importance of factors other than standard visual acuity. Speculation is offered on potential strategies and solutions for rehabilitation as well as the need for future research and improvements in service delivery.
Topics: Activities of Daily Living; Cost of Illness; Deaf-Blind Disorders; Humans; Interdisciplinary Communication; Patient Care Team; Persons With Hearing Impairments; Quality of Life; Referral and Consultation; Severity of Illness Index; Vision Tests; Visually Impaired Persons
PubMed: 18003865
DOI: 10.1177/1084713807307410 -
Scientific Reports Sep 2023Although rarely reported, bilateral loss of vision is a severe complication of childhood bacterial meningitis. We assessed its frequency in five prospective treatment...
Although rarely reported, bilateral loss of vision is a severe complication of childhood bacterial meningitis. We assessed its frequency in five prospective treatment trials performed in Europe, Latin America, and Angola in 1984-2017. Course of illness, follow-up findings, and child's sight were recorded. Sight was examined at discharge, and conditions permitting, also at 1-3 months post-hospitalization and in Angola on hospital day 7. Experienced pediatricians diagnosed clinical blindness if the child did not make eye contact, did not blink or move the eyes, or remained unresponsive to bright light or movement of large objects before their eyes. Of 1515 patients, 351, 654, and 510 were from Finland, Latin America, and Angola, respectively. At discharge, blindness was observed in 0 (0%), 8 (1.2%), and 51 (10%) children, respectively. In Angola, 64 children appeared to be blind on day 7; 16 of these children died. Blindness found at discharge in Angola was not invariably irreversible; approximately 40% had restored the sight at follow-up visit. Clinical blindness rarely occurred in isolation and was usually associated with young age and poor general condition at hospital arrival. Various other serious sequelae were common among the survivors with clinical blindness.
Topics: Child; Humans; Blindness; Eye; Visually Impaired Persons; Angola; Meningitis, Bacterial
PubMed: 37726355
DOI: 10.1038/s41598-023-41685-2 -
JAMA Ophthalmology Sep 2017Visual dysfunction and poor cognition are highly prevalent among older adults; however, the relationship is not well defined.
IMPORTANCE
Visual dysfunction and poor cognition are highly prevalent among older adults; however, the relationship is not well defined.
OBJECTIVE
To evaluate the association of measured and self-reported visual impairment (VI) with cognition in older US adults.
DESIGN, SETTING, AND PARTICIPANTS
Cross-sectional analysis of 2 national data sets: the National Health and Nutrition Examination Survey (NHANES), 1999-2002, and the National Health and Aging Trends Study (NHATS), 2011-2015. The NHANES was composed of a civilian, noninstitutionalized community, and the NHATS comprised Medicare beneficiaries in the contiguous United States. Vision was measured at distance, near, and by self-report in the NHANES and by self-report alone in the NHATS. Sample weights were used to ensure result generalizability.
MAIN OUTCOMES AND MEASURES
The NHANES measured Digit Symbol Substitution Test (DSST) score and relative DSST impairment (DSST score ≤28, lowest quartile in study cohort), and the NHATS measured probable or possible dementia, classified per NHATS protocol.
RESULTS
The NHANES comprised 2975 respondents aged 60 years and older who completed the DSST measuring cognitive performance. Mean (SD) age was 72 (8) years, 52% of participants were women (n = 1527), and 61% were non-Hispanic white (n = 1818). The NHATS included 30 202 respondents aged 65 years and older with dementia status assessment. The largest proportion (40%; n = 12 212) were between 75 and 84 years of age. Fifty-eight percent were women (n = 17 659), and 69% were non-Hispanic white (n = 20 842). In the NHANES, distance VI (β = -5.1; 95% CI, -8.6 to -1.6; odds ratio [OR], 2.8; 95% CI, 1.1-6.7) and subjective VI (β = -5.3; 95% CI, -8.0 to -2.6; OR, 2.7; 95% CI, 1.6-4.8) were both associated with lower DSST scores and higher odds of DSST impairment after full adjustment with covariates. Near VI was associated with lower DSST scores but not higher odds of DSST impairment. The NHATS data corroborated these results, with all vision variables associated with higher odds of dementia after full adjustment (distance VI: OR, 1.9; 95% CI, 1.6-2.2; near VI: OR, 2.6; 95% CI, 2.2-3.1; either distance or near VI: OR, 2.1; 95% CI, 1.8-2.4).
CONCLUSIONS AND RELEVANCE
In a nationally representative sample of older US adults, vision dysfunction at distance and based on self-reports was associated with poor cognitive function. This was substantiated by a representative sample of US Medicare beneficiaries using self-reported visual function, reinforcing the value of identifying patients with visual compromise. Further study of longitudinal interactions between vision and cognition is warranted.
Topics: Aged; Aged, 80 and over; Blindness; Cognition Disorders; Cross-Sectional Studies; Dementia; Female; Humans; Male; Middle Aged; Neuropsychological Tests; Nutrition Surveys; United States; Vision, Low; Visual Acuity; Visually Impaired Persons
PubMed: 28817745
DOI: 10.1001/jamaophthalmol.2017.2838 -
American Journal of Ophthalmology Aug 2021To evaluate the effect of population screening on low vision and blindness from open-angle glaucoma.
PURPOSE
To evaluate the effect of population screening on low vision and blindness from open-angle glaucoma.
DESIGN
Retrospective cohort study.
METHODS
A large population-based screening for glaucoma was conducted in Malmö, Sweden, from 1992 to 1997. A total of 42,497 subjects were invited, of which 32,918 were screened, and 9,579 were non-responders (ie, did not participate). The records of glaucoma patients who had visited the Department of Ophthalmology at Malmö University Hospital from January 1, 1987, to December 31, 2017, were reviewed. Patients diagnosed at or after the screening were assessed for moderate or severe vision impairment, here called low vision, or blindness by the World Health Organization definition. Selection bias was corrected by creating a group of potential screening participants from a comparison group of clinical patients. Main outcome measures were the risk ratios of the cumulative incidence for bilateral low vision or blindness caused by glaucoma in screened patients compared with the potential participants.
RESULTS
The cumulative incidence of blindness was 0.17% in the screened population versus 0.32% among the potential participants; and for low vision 0.25% versus 0.53%. The risk ratio (95% confidence interval) between the two was 0.52 (0.32-0.84) for blindness and 0.46 (0.31-0.68) for low vision. There were no differences between the proportions of potential confounders in the comparison group and those in the non-responders.
CONCLUSIONS
The results suggest that population screening may reduce bilateral low vision and blindness caused by glaucoma by approximately 50%.
Topics: Aged; Aged, 80 and over; Blindness; Female; Follow-Up Studies; Glaucoma, Open-Angle; Humans; Incidence; Intraocular Pressure; Male; Mass Screening; Retrospective Studies; Sweden; Visual Acuity; Visually Impaired Persons
PubMed: 33823158
DOI: 10.1016/j.ajo.2021.03.030 -
Sensors (Basel, Switzerland) Dec 2022In this work, we presented a novel encoding method for tactile communication. This approach was based on several tactile sensory characteristics of human skin at...
In this work, we presented a novel encoding method for tactile communication. This approach was based on several tactile sensory characteristics of human skin at different body parts, such as the head and neck, where location coordinates in the three-dimensional (3D) space were clearly mapped in the brain cortex, and gentle stimulations of vibrational touching with varied strengths were received instantly and precisely. For certain applications, such as playing cards or navigating walk paths for blinded people, we demonstrated specifically designed code lists with different patterns of tactile points in varied temporal sequences. By optimizing these codes, we achieved excellent efficiency and accuracy in our test experiments. As this method matched well with the natural habits of tactile sensory, it was easy to learn in a short training period. The results of the present work have offered a silent, efficient and accurate communication solution for visually impaired people or other users.
Topics: Humans; Touch; Touch Perception; Skin; Wearable Electronic Devices; Visually Impaired Persons
PubMed: 36559936
DOI: 10.3390/s22249568 -
International Journal of Environmental... Aug 2022The use of ICTs provides autonomy, equity, and social inclusion to people with visual disabilities. The National Organization of the Spanish Blind (ONCE) offers its...
The use of ICTs provides autonomy, equity, and social inclusion to people with visual disabilities. The National Organization of the Spanish Blind (ONCE) offers its 70,462 legally-blind people the necessary resources for the usability of ICTs. Still, most individuals with visual disabilities do not have a similar support system. This research aims to expose and make visible the importance and need for ICTs usage in this group. The qualitative approach has allowed the modeling of a contextualized inductive process through two heterogeneous discussion groups: eight individuals with legal blindness and six with moderate visual impairment, as well as three in-depth interviews with experts in typhlotechnology, accessibility, and low vision. The following has been verified: there is a lot of misinformation among people with visual disabilities outside the coverage of ONCE; accessibility is still not a priority for companies and institutions when creating and developing products and services with Design for All; the need for more professionals to advise and train users with blindness and low vision is clear. In Spain, there are almost a million visually-impaired people not affiliated with ONCE, for whom access to technical aids and digital literacy is a priority problem in which the Government should intervene.
Topics: Blindness; Disabled Persons; Humans; Spain; Vision, Low; Visually Impaired Persons
PubMed: 36078497
DOI: 10.3390/ijerph191710782 -
Asia-Pacific Journal of Ophthalmology... Sep 2021The Asia-Pacific region is home to a 4.3-billion population and one of the most rapidly aging regions. Addressing the eye care needs in the region would greatly boost...
The Asia-Pacific region is home to a 4.3-billion population and one of the most rapidly aging regions. Addressing the eye care needs in the region would greatly boost the progress toward achieving universal eye health. Over 20 countries/regions have actively engaged in the "VISION 2020" initiative launched since 1999, and remarkable achievements have been witnessed as demonstrated by an increase in both the number and density of ophthalmologists in almost all countries. Nevertheless, formidable and emerging challenges are to be overcome in the coming century. From 1990 to 2015, the absolute number of blind people increased by 17.9%, largely due to population growth and aging. The Asia-Pacific region, the most populous continent with a rapidly aging population, would inevitably be left to tackle this challenge. Furthermore, a high prevalence of blinding eye diseases imposes great pressure on current eye care services, with South Asia having the highest age-standardized prevalence of moderate to severe visual impairment (17.5%) and mild vision impairment (12.2%) globally, and high-income countries having the highest overall prevalence of myopia, reaching 53.4% with East Asia having the second-highest overall prevalence (51.6%). Moreover, the availability of ophthalmic resources varies greatly in the region, with the density of ophthalmologists ranging from over 114 ophthalmologists per million population in Japan to 0 in Micronesia, and a highly disproportionate urban-rural distribution. This article aims to shed light on challenges faced by the Asia-Pacific ophthalmic community and propose corresponding strategies to tackle those challenges.
Topics: Aged; Asia; Blindness; Asia, Eastern; Humans; Prevalence; Visually Impaired Persons
PubMed: 34516436
DOI: 10.1097/APO.0000000000000391 -
Sensors (Basel, Switzerland) Jun 2023Several assistive technology solutions, targeting the group of Blind and Visually Impaired (BVI), have been proposed in the literature utilizing multi-sensor data fusion... (Review)
Review
Several assistive technology solutions, targeting the group of Blind and Visually Impaired (BVI), have been proposed in the literature utilizing multi-sensor data fusion techniques. Furthermore, several commercial systems are currently being used in real-life scenarios by BVI individuals. However, given the rate by which new publications are made, the available review studies become quickly outdated. Moreover, there is no comparative study regarding the multi-sensor data fusion techniques between those found in the research literature and those being used in the commercial applications that many BVI individuals trust to complete their everyday activities. The objective of this study is to classify the available multi-sensor data fusion solutions found in the research literature and the commercial applications, conduct a comparative study between the most popular commercial applications (Blindsquare, Lazarillo, Ariadne GPS, Nav by ViaOpta, Seeing Assistant Move) regarding the supported features as well as compare the two most popular ones (Blindsquare and Lazarillo) with the BlindRouteVision application, developed by the authors, from the standpoint of Usability and User Experience (UX) through field testing. The literature review of sensor-fusion solutions highlights the trends of utilizing computer vision and deep learning techniques, the comparison of the commercial applications reveals their features, strengths, and weaknesses while Usability and UX demonstrate that BVI individuals are willing to sacrifice a wealth of features for more reliable navigation.
Topics: Humans; Blindness; Visually Impaired Persons; Self-Help Devices; Sensory Aids
PubMed: 37420578
DOI: 10.3390/s23125411