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American Family Physician May 2008Blindness or low vision affects more than 3 million Americans 40 years and older, and this number is projected to reach 5.5 million by 2020. In addition to treating a... (Review)
Review
Blindness or low vision affects more than 3 million Americans 40 years and older, and this number is projected to reach 5.5 million by 2020. In addition to treating a patient's vision loss and comorbid medical issues, physicians must be aware of the physical limitations and social issues associated with vision loss to optimize health and independent living for the visually impaired patient. In the United States, the four most prevalent etiologies of vision loss in persons 40 years and older are age-related macular degeneration, cataracts, glaucoma, and diabetic retinopathy. Exudative macular degeneration is treated with laser therapy, and progression of nonexudative macular degeneration in its advanced stages may be slowed with high-dose antioxidant and zinc regimens. The value of screening for glaucoma is uncertain; management of this condition relies on topical ocular medications. Cataract symptoms include decreased visual acuity, decreased color perception, decreased contrast sensitivity, and glare disability. Lifestyle and environmental interventions can improve function in patients with cataracts, but surgery is commonly performed if the condition worsens. Diabetic retinopathy responds to tight glucose control, and severe cases marked by macular edema are treated with laser photocoagulation. Vision-enhancing devices can help magnify objects, and nonoptical interventions include special filters and enhanced lighting.
Topics: Aged; Cataract; Diabetic Retinopathy; Eye Diseases; Female; Glaucoma; Health Knowledge, Attitudes, Practice; Humans; Macular Degeneration; Male; Middle Aged; Patient Education as Topic; Prevalence; Primary Health Care; Quality of Life; United States; Vision Disorders; Visual Acuity; Visually Impaired Persons
PubMed: 18533377
DOI: No ID Found -
Neuroscience and Biobehavioral Reviews Dec 2016The last quarter of a century has seen a dramatic rise of interest in the development of technological solutions for visually impaired people. However, despite the... (Review)
Review
The last quarter of a century has seen a dramatic rise of interest in the development of technological solutions for visually impaired people. However, despite the presence of many devices, user acceptance is low. Not only are visually impaired adults not using these devices but they are also too complex for children. The majority of these devices have been developed without considering either the brain mechanisms underlying the deficit or the natural ability of the brain to process information. Most of them use complex feedback systems and overwhelm sensory, attentional and memory capacities. Here we review the neuroscientific studies on orientation and mobility in visually impaired adults and children and present the technological devices developed so far to improve locomotion skills. We also discuss how we think these solutions could be improved. We hope that this paper may be of interest to neuroscientists and technologists and it will provide a common background to develop new science-driven technology, more accepted by visually impaired adults and suitable for children with visual disabilities.
Topics: Adult; Child; Humans; Locomotion; Memory; Orientation; Visually Impaired Persons
PubMed: 27608959
DOI: 10.1016/j.neubiorev.2016.08.019 -
Annual Review of Vision Science Sep 2023The pervasiveness of mobile devices and other associated technologies has affected all aspects of our daily lives. People with visual impairments are no exception, as... (Review)
Review
The pervasiveness of mobile devices and other associated technologies has affected all aspects of our daily lives. People with visual impairments are no exception, as they increasingly tend to rely on mobile apps for assistance with various visual tasks in daily life. Compared to dedicated visual aids, mobile apps offer advantages such as affordability, versatility, portability, and ubiquity. We have surveyed hundreds of mobile apps of potential interest to people with vision impairments, either released as special assistive apps claiming to help in tasks such as text or object recognition ( = 68), digital accessibility ( = 84), navigation ( = 44), and remote sighted service ( = 4), among others, or marketed as general camera magnification apps that can be used for visual assistance ( = 77). While assistive apps as a whole received positive feedback from visually impaired users, as reported in various studies, evaluations of the usability of every app were typically limited to user reviews, which are often not scientifically informative. Rigorous evaluation studies on the effect of vision assistance apps on daily task performance and quality of life are relatively rare. Moreover, evaluation criteria are difficult to establish, given the heterogeneity of the visual tasks and visual needs of the users. In addition to surveying literature on vision assistance apps, this review discusses the feasibility and necessity of conducting scientific research to understand visual needs and methods to evaluate real-world benefits.
Topics: Humans; Visually Impaired Persons; Quality of Life; Self-Help Devices; Mobile Applications; Visual Perception
PubMed: 37127283
DOI: 10.1146/annurev-vision-111022-123837 -
Acta Ophthalmologica Mar 2010This article, based on a report prepared for the International Council of Ophthalmology (ICO) and the International Society for Low Vision Research and Rehabilitation... (Review)
Review
This article, based on a report prepared for the International Council of Ophthalmology (ICO) and the International Society for Low Vision Research and Rehabilitation (ISLRR), explores the assessment of various aspects of visual functioning as needed to document the outcomes of vision rehabilitation. Documenting patient abilities and functional vision (how the person functions) is distinct from the measurement of visual functions (how the eye functions) and also from the assessment of quality of life. All three areas are important, but their assessment should not be mixed. Observation of task performance offers the most objective measure of functional vision, but it is time-consuming and not feasible for many tasks. Where possible, timing and error rates provide an easy score. Patient response questionnaires provide an alternative. They may save time and can cover a wider area, but the responses are subjective and proper scoring presents problems. Simple Likert scoring still predominates but Rasch analysis, needed to provide better result scales, is gaining ground. Selection of questions is another problem. If the range of difficulties does not match the range of patient abilities, and if the difficulties are not distributed evenly, the results are not optimal. This may be an argument to use different outcome questions for different conditions. Generic questionnaires are appropriate for the assessment of generic quality of life, but not for specific rehabilitation outcomes. Different questionnaires are also needed for screening, intake and outcomes. Intake questions must be relevant to actual needs to allow prioritization of rehabilitation goals; the activity inventory presents a prototype. Outcome questions should be targeted at predefined rehabilitation goals. The Appendix cites some promising examples. The Low Vision Intervention Trial (LOVIT) is an example of a properly designed randomized control study, and has demonstrated the remarkable effectiveness of vision rehabilitation. It is hoped that further similar studies will follow.
Topics: Disability Evaluation; Humans; Vision Disorders; Vision, Ocular; Visually Impaired Persons
PubMed: 20039847
DOI: 10.1111/j.1755-3768.2009.01670.x -
Sensors (Basel, Switzerland) Jul 2021A diverse array of assistive technologies have been developed to help Visually Impaired People (VIP) face many basic daily autonomy challenges. Inertial measurement unit... (Review)
Review
A diverse array of assistive technologies have been developed to help Visually Impaired People (VIP) face many basic daily autonomy challenges. Inertial measurement unit sensors, on the other hand, have been used for navigation, guidance, and localization but especially for full body motion tracking due to their low cost and miniaturization, which have allowed the estimation of kinematic parameters and biomechanical analysis for different field of applications. The aim of this work was to present a comprehensive approach of assistive technologies for VIP that include inertial sensors as input, producing results on the comprehension of technical characteristics of the inertial sensors, the methodologies applied, and their specific role in each developed system. The results show that there are just a few inertial sensor-based systems. However, these sensors provide essential information when combined with optical sensors and radio signals for navigation and special application fields. The discussion includes new avenues of research, missing elements, and usability analysis, since a limitation evidenced in the selected articles is the lack of user-centered designs. Finally, regarding application fields, it has been highlighted that a gap exists in the literature regarding aids for rehabilitation and biomechanical analysis of VIP. Most of the findings are focused on navigation and obstacle detection, and this should be considered for future applications.
Topics: Biomechanical Phenomena; Humans; Motion; Self-Help Devices; Visually Impaired Persons
PubMed: 34300507
DOI: 10.3390/s21144767 -
Investigative Ophthalmology & Visual... Dec 2016Spatial updating is the ability to keep track of position and orientation while moving through an environment. We asked how normally sighted and visually impaired...
PURPOSE
Spatial updating is the ability to keep track of position and orientation while moving through an environment. We asked how normally sighted and visually impaired subjects compare in spatial updating and in estimating room dimensions.
METHODS
Groups of 32 normally sighted, 16 low-vision, and 16 blind subjects estimated the dimensions of six rectangular rooms. Updating was assessed by guiding the subjects along three-segment paths in the rooms. At the end of each path, they estimated the distance and direction to the starting location, and to a designated target. Spatial updating was tested in five conditions ranging from free viewing to full auditory and visual deprivation.
RESULTS
The normally sighted and low-vision groups did not differ in their accuracy for judging room dimensions. Correlations between estimated size and physical size were high. Accuracy of low-vision performance was not correlated with acuity, contrast sensitivity, or field status. Accuracy was lower for the blind subjects. The three groups were very similar in spatial-updating performance, and exhibited only weak dependence on the nature of the viewing conditions.
CONCLUSIONS
People with a wide range of low-vision conditions are able to judge room dimensions as accurately as people with normal vision. Blind subjects have difficulty in judging the dimensions of quiet rooms, but some information is available from echolocation. Vision status has little impact on performance in simple spatial updating; proprioceptive and vestibular cues are sufficient.
Topics: Adult; Aged; Aged, 80 and over; Blindness; Cues; Female; Humans; Male; Middle Aged; Orientation; Proprioception; Psychomotor Performance; Space Perception; Spatial Navigation; Vision, Low; Visually Impaired Persons; Young Adult
PubMed: 27978556
DOI: 10.1167/iovs.16-20226 -
Survey of Ophthalmology 2012Visual impairment is a large and growing socioeconomic problem. Good evidence on rehabilitation outcomes is required to guide service development and improve the lives... (Review)
Review
Visual impairment is a large and growing socioeconomic problem. Good evidence on rehabilitation outcomes is required to guide service development and improve the lives of people with sight loss. Of the 478 potentially relevant articles identified, only 58 studies met our liberal inclusion criteria, and of these only 7 were randomized controlled trials. Although the literature is sufficient to confirm that rehabilitation services result in improved clinical and functional ability outcomes, the effects on mood, vision-related quality of life (QoL) and health-related QoL are less clear. There are some good data on the performance of particular types of intervention, but almost no useful data about outcomes in children, those of working age, and other groups. There were no reports on cost effectiveness. Overall, the number of well-designed and adequately reported studies is pitifully small; visual rehabilitation research needs higher quality research. We highlight study design and reporting considerations and suggest a future research agenda.
Topics: Activities of Daily Living; Cost-Benefit Analysis; Disability Evaluation; Health Services; Health Status Indicators; Humans; Quality of Life; Treatment Outcome; Vision, Low; Visually Impaired Persons
PubMed: 22018676
DOI: 10.1016/j.survophthal.2011.06.006 -
Middle East African Journal of... 2015The aim was to assess the impact of cataract surgeries in reducing visual disabilities and factors influencing it at three institutes of India. (Review)
Review
PURPOSE
The aim was to assess the impact of cataract surgeries in reducing visual disabilities and factors influencing it at three institutes of India.
MATERIALS AND METHODS
A retrospective chart review was performed in 2013. Data of 4 years were collected on gender, age, residence, presenting a vision in each eye, eye that underwent surgery, type of surgery and the amount the patient paid out of pocket for surgery. Visual impairment was categorized as; absolute blindness (no perception of light); blind (<3/60); severe visual impairment (SVI) (<6/60-3/60); moderate visual impairment (6/18-6/60) and; normal vision (≥6/12). Statistically analysis was performed to evaluate the association between visual disabilities and demographics or other possible barriers. The trend of visual impairment over time was also evaluated. We compared the data of 2011 to data available about cataract cases from institutions between 2002 and 2009.
RESULTS
There were 108,238 cataract cases (50.6% were female) that underwent cataract surgery at the three institutions. In 2011, 71,615 (66.2%) cases underwent surgery. There were 45,336 (41.9%) with presenting vision < 3/60 and 75,393 (69.7%) had SVI in the fellow eye. Blindness at presentation for cataract surgery was associated to, male patients, Institution 3 (Dristi Netralaya, Dahod) surgeries after 2009, cataract surgeries without Intra ocular lens implant implantation, and patients paying <25 US $ for surgery. Predictors of SVI at time of cataract surgery were, male, Institution 3 (OM), phaco surgeries, those opting to pay 250 US $ for cataract surgeries.
CONCLUSION
Patients with cataract seek eye care in late stages of visual disability. The goal of improving vision related quality of life for cataract patients during the early stages of visual impairment that is common in industrialized countries seems to be non-attainable in the rural India.
Topics: Aged; Cataract Extraction; Female; Humans; India; Male; Middle Aged; Quality of Life; Retrospective Studies; Vision Disorders; Visual Acuity; Visually Impaired Persons
PubMed: 25624679
DOI: 10.4103/0974-9233.148354 -
Indian Journal of Ophthalmology Aug 2021To determine the causes of severe visual impairment and blindness in children in schools for the blind in the city of Bangalore, Karnataka and to determine the error of... (Review)
Review
PURPOSE
To determine the causes of severe visual impairment and blindness in children in schools for the blind in the city of Bangalore, Karnataka and to determine the error of inclusion and exclusion from these schools.
METHODS
This was a cross-sectional study. Children in four schools for the blind were subjected to a detailed ophthalmic evaluation. The World Health Organization Program for Prevention of Blindness low-vision form was used to collect data. To know the educational background of children with visual disability of 40% or more (best-corrected visual acuity of ≤6/24 in the better eye), not in schools for the blind, we collected data by telephonic conversation after procuring their phone numbers from our low-vision clinic.
RESULTS
One-hundred-seventy-eight children were examined. The major site of anomaly causing blindness in 31% of children was optic nerve, followed by retina (24%), cornea (23%), and whole globe (22%). Avoidable blindness was 35.42%. Thirteen percent of the children with no visual disability were incorrectly enrolled in blind schools. We were able to contact 92 children with a visual disability of ≥40%. Seventy-eight children (84.78%) attended regular schools; these schools were bereft of a specially trained teacher to look after the needs of the blind.
CONCLUSION
Avoidable blindness is still a cause for concern. Children should undergo eye-examination before being enrolled in schools for the blind to avoid errors of inclusion. Though integrated education for children with vision disability is a good approach, it requires teachers trained in teaching skills particular to blindness. Education for the visually impaired in India needs a major revision.
Topics: Blindness; Child; Cross-Sectional Studies; Humans; India; Schools; Vision, Low; Visually Impaired Persons
PubMed: 34304171
DOI: 10.4103/ijo.IJO_3725_20 -
Eye (London, England) Oct 2022To assess the main causes leading to childhood visual impairment/blindness in a center for low vision in Israel and to analyze the literature on pediatric blinding... (Review)
Review
BACKGROUND
To assess the main causes leading to childhood visual impairment/blindness in a center for low vision in Israel and to analyze the literature on pediatric blinding diseases in developed countries.
METHODS
Retrospective study based on observational case series. Data were obtained from medical records of visually impaired children, seen at a national referral low vision center. Children were divided into two groups: moderate visual impairment (6/18 to 6/60) and severe visual impairment (SVI)/blindness (<6/60). Inherited eye diseases (IED) were grouped together for analysis. Data from the Israeli blind registry from the same period of time were analyzed for comparison. A review of literature on childhood blindness in developed countries since 2000 was conducted.
RESULTS
A total of 1393 children aged 0-18 years were included in the study. Moderate visual impairment was seen in 1025 (73.6%) and SVI/blindness in 368 (26.4%) of the studied children. Among blind children, IED accounted for at least 51% of all diagnoses, including mainly albinism and retinal dystrophies. IED prevalence was equally high in both main ethnic groups (Jewish and Arab Muslims). Non-IED (22.6%) included mainly patients with cerebral visual impairment and retinopathy of prematurity.
CONCLUSIONS
The leading cause of childhood visual impairment and blindness in our patient cohort was IED. Analyses of the literature from the last two decades show that IED are a major cause for SVI/childhood blindness in other developed countries as well. Updated patterns of global childhood blindness may suggest a need for new approach for screening programs and modern tactics for prevention.
Topics: Blindness; Child; Eye Diseases, Hereditary; Humans; Infant, Newborn; Israel; Retrospective Studies; Vision Disorders; Vision, Low; Visual Acuity; Visually Impaired Persons
PubMed: 34426656
DOI: 10.1038/s41433-021-01743-3