-
Clinical & Experimental Optometry Nov 2007Africa carries a disproportionate responsibility in terms of blindness and visual impairment. With approximately 10 per cent of the world's population, Africa has 19 per... (Review)
Review
Africa carries a disproportionate responsibility in terms of blindness and visual impairment. With approximately 10 per cent of the world's population, Africa has 19 per cent of the world's blindness. It is no surprise that this reality also mirrors the situation in terms of the burden of world poverty. There is an increasing recognition of the need to highlight the link between poverty, development and health care. Blindness, disabling visual impairment and the overall lack of eye-care services are too often the result of social, economic and developmental challenges of the developing world. The state of eye care in Africa stands in alarming contrast to that in the rest of the world. Poor practitioner-to-patient ratios, absence of eye-care personnel, inadequate facilities, poor state funding and a lack of educational programs are the hallmarks of eye care in Africa, with preventable and treatable conditions being the leading cause of blindness. Eye diseases causing preventable blindness are often the result of a combination of factors such as poverty, lack of education and inadequate health-care services. The challenge that Vision 2020 has set itself in Africa is enormous. Africa is not a homogenous entity, the inter- and intra-country differences in economic development, prevalence of disease, delivery infrastructure and human resources amplify the challenges of meeting eye-care needs. The successful implementation of Vision 2020 programs will be hindered without the development of a comprehensive, co-ordinated strategy that is cognisant of the differences that exist and the need for comprehensive solutions that are rooted in the economic and political realities of the continent as well as the individual countries and regions within countries. This strategy should recognise the need for economic growth that results in greater state funded eye-care services that focus on health promotion to ensure the prevention of eye disease, the development of eye clinics in hospitals and health clinics, and the training of the appropriate human resources.
Topics: Africa; Blindness; Humans; Poverty; Prevalence; Public Health; Risk Factors; Socioeconomic Factors
PubMed: 17958563
DOI: 10.1111/j.1444-0938.2007.00197.x -
Clinical & Experimental Optometry Nov 2007A few recent studies have shown that poverty is an exacerbating and often determining factor in the incidence of disabling conditions, including visual impairment.... (Review)
Review
A few recent studies have shown that poverty is an exacerbating and often determining factor in the incidence of disabling conditions, including visual impairment. Recent estimates from the World Health Organization indicate that 90 per cent of all those affected by visual impairment live in the poorest countries of the world. India is home to one-fifth of the world's visually impaired people and therefore, any strategies to combat avoidable blindness must take into account the socio-economic conditions within which people live. This paper looks at the relationship between poverty and blindness in India and suggests strategies to address blindness prevention in a comprehensive manner.
Topics: Blindness; Humans; India; Poverty; Prevalence; Refractive Errors; Risk Factors; Socioeconomic Factors
PubMed: 17958562
DOI: 10.1111/j.1444-0938.2007.00199.x -
Acta Biomaterialia Mar 2018Corneal blindness is traditionally treated by transplantation of a donor cornea, or in severe cases by implantation of an artificial cornea or keratoprosthesis. Due to... (Review)
Review
UNLABELLED
Corneal blindness is traditionally treated by transplantation of a donor cornea, or in severe cases by implantation of an artificial cornea or keratoprosthesis. Due to severe donor shortages and the risks of complications that come with artificial corneas, tissue engineering in ophthalmology has become more focused on regenerative strategies using biocompatible materials either with or without cells. The stroma makes up the bulk of the corneal thickness and mainly consists of a tightly interwoven network of collagen type I, making it notoriously difficult to recreate in a laboratory setting. Despite the challenges that come with corneal stromal tissue engineering, there has recently been enormous progress in this field. A large number of research groups are working towards developing the ideal biomimetic, cytocompatible and transplantable stromal replacement. Here we provide an overview of the approaches directed towards tissue engineering the corneal stroma, from classical collagen gels, films and sponges to less traditional components such as silk, fish scales, gelatin and polymers. The perfect stromal replacement has yet to be identified and future research should be directed at combined approaches, in order to not only host native stromal cells but also restore functionality.
STATEMENT OF SIGNIFICANCE
In the field of tissue engineering and regenerative medicine in ophthalmology the focus has shifted towards a common goal: to restore the corneal stroma and thereby provide a new treatment option for patients who are currently blind due to corneal opacification. Currently the waiting lists for corneal transplantation include more than 10 million patients, due to severe donor shortages. Alternatives to the transplantation of a donor cornea include the use of artificial cornea, but these are by no means biomimetic and therefore do not provide good outcomes. In recent years a lot of work has gone into the development of tissue engineered scaffolds and other biomaterials suitable to replace the native stromal tissue. Looking at all the different approaches separately is a daunting task and up until now there was no review article in which every approach is discussed. This review does include all approaches, from classical tissue engineering with collagen to the use of various alternative biomaterials and even fish scales. Therefore, this review can serve as a reference work for those starting in the field and but also to stimulate collaborative efforts in the future.
Topics: Animals; Biomimetic Materials; Bioprosthesis; Blindness; Collagen Type I; Corneal Stroma; Humans; Regeneration; Tissue Engineering
PubMed: 29374600
DOI: 10.1016/j.actbio.2018.01.023 -
Arquivos Brasileiros de Oftalmologia 2020The burden of corneal blindness and visual deficiency can be felt worldwide. Its association with several endemic diseases such as childhood blindness, trauma,... (Review)
Review
The burden of corneal blindness and visual deficiency can be felt worldwide. Its association with several endemic diseases such as childhood blindness, trauma, infectious keratitis (including variants caused by herpes, hanseniasis, and fungi), vitamin A deficiency, diabetes mellitus, and other dry eye syndromes reflects its poorly understood underlying mechanisms and suggests that the actual frequency of the disease is underestimated. The low effectiveness of preventive and therapeutic strategies against corneal scarring or deformity predicts a high frequency of patients with corneal blindness in the future. Corneal blindness is associated with environmental factors and socioeconomic limitations that restrain health assistance and maintain a modest efficiency of the current therapeutic strategies for resolving corneal diseases in large-scale programs. We present here a critical review of the concepts associated with corneal blindness that need to be considered when planning strategies to prevent and treat corneal blindness worldwide (to be able to leave Plato's cave, where corneal blindness is encaged.
Topics: Blindness; Corneal Diseases; Corneal Injuries; Corneal Opacity; Humans; Keratitis
PubMed: 33084821
DOI: 10.5935/0004-2749.20200102 -
BMJ (Clinical Research Ed.) Oct 2003
Topics: Blindness; Cataract; Child; Cost-Benefit Analysis; Global Health; Health Priorities; Humans; Infant, Newborn; Measles; Prevalence; Retinopathy of Prematurity; Vitamin A Deficiency
PubMed: 14525849
DOI: 10.1136/bmj.327.7418.760 -
Wiley Interdisciplinary Reviews.... 2016Spatial navigation in the absence of vision has been investigated from a variety of perspectives and disciplines. These different approaches have progressed our... (Review)
Review
Spatial navigation in the absence of vision has been investigated from a variety of perspectives and disciplines. These different approaches have progressed our understanding of spatial knowledge acquisition by blind individuals, including their abilities, strategies, and corresponding mental representations. In this review, we propose a framework for investigating differences in spatial knowledge acquisition by blind and sighted people consisting of three longitudinal models (i.e., convergent, cumulative, and persistent). Recent advances in neuroscience and technological devices have provided novel insights into the different neural mechanisms underlying spatial navigation by blind and sighted people and the potential for functional reorganization. Despite these advances, there is still a lack of consensus regarding the extent to which locomotion and wayfinding depend on amodal spatial representations. This challenge largely stems from methodological limitations such as heterogeneity in the blind population and terminological ambiguity related to the concept of cognitive maps. Coupled with an over-reliance on potential technological solutions, the field has diffused into theoretical and applied branches that do not always communicate. Here, we review research on navigation by congenitally blind individuals with an emphasis on behavioral and neuroscientific evidence, as well as the potential of technological assistance. Throughout the article, we emphasize the need to disentangle strategy choice and performance when discussing the navigation abilities of the blind population. For further resources related to this article, please visit the WIREs website.
Topics: Blindness; Brain; Humans; Space Perception; Spatial Learning; Spatial Navigation
PubMed: 26683114
DOI: 10.1002/wcs.1375 -
Graefe's Archive For Clinical and... Dec 2021Blindness and vision loss are still frequent disabilities associated with a relevant impact on health care and quality of life, and a high economic burden. Supranational... (Review)
Review
PURPOSE
Blindness and vision loss are still frequent disabilities associated with a relevant impact on health care and quality of life, and a high economic burden. Supranational programs established by the World Health Organization (WHO), International Agency for the Prevention of Blindness (IAPB), and World Health Assembly (WHA) aim at reducing avoidable visual impairment. Age-related macular degeneration (AMD), diabetic retinopathy (DR), and other retinal diseases are well known causes of visual disability. Since more than a decade, intravitreal agents are available for the treatment of these diseases. The aim of this study is to review whether pharmacotherapy with anti-vascular endothelial growth factor (VEGF) drugs has led to a decrease in the prevalence of blindness with emphasis on AMD and different countries. A brief analysis of other factors correlated to changes in the rate of blindness is also presented.
METHODS
PubMed and Scopus web platforms were used to identify relevant studies on epidemiology of blindness and vision impairment, the influence of intravitreal therapies, and the existence of different vision care models. Additional data and material was searched in web internet accessed by the web browser Firefox.
RESULTS
Age-standardized prevalence of blindness secondary to AMD has started to decline as testified by a number of studies in different countries. This is due to the adoption of anti-VEGF therapy and its adequate management. The frequency of treatment and regimens applied are indirect signs of successful treatment. Local rules and regulations may represent an obstacle.
CONCLUSIONS
This review shows that by implementing existing health care systems and dispensing adequate therapies in the field of retinal diseases, the prevalence of blindness due to these conditions can decline.
Topics: Angiogenesis Inhibitors; Blindness; Humans; Macular Degeneration; Quality of Life; Vascular Endothelial Growth Factors; Visual Acuity
PubMed: 34669026
DOI: 10.1007/s00417-021-05451-2 -
Neuron Nov 2016The brain has often been described, quite accurately, as one of the most complex objects in the natural world. Understanding its workings, to say nothing about...
The brain has often been described, quite accurately, as one of the most complex objects in the natural world. Understanding its workings, to say nothing about intervening in them, is among the hardest problems in science. While this makes the challenge all the more enticing, in the short term, it acts to limit the impact that neuroscience can have on real-world problems. A comprehensive understanding of fundamental principles of brain function, and their translation into treatments for brain disorders, may be decades away. Even as we pursue these long-term goals, what are the prospects for our field to engage with some of the pressing challenges the world currently faces? An initiative that I have had the opportunity of being involved with, Project Prakash, illustrates one way forward. The operational model that it has adopted enables an immediate merging of basic research and societal service.
Topics: Blindness; Humans; Neurosciences; Social Responsibility
PubMed: 27810010
DOI: 10.1016/j.neuron.2016.10.044 -
Indian Journal of Ophthalmology May 2018Keratoprosthesis (Kpro) forms the last resort for bilateral end-stage corneal blindness. The Boston Type 1 and 2 Kpros, the modified osteo-odonto Kpro and the osteo-Kpro... (Review)
Review
Keratoprosthesis (Kpro) forms the last resort for bilateral end-stage corneal blindness. The Boston Type 1 and 2 Kpros, the modified osteo-odonto Kpro and the osteo-Kpro are the more frequently and commonly performed Kpros, and this review attempts to compile the current data available on these Kpros worldwide from large single-center studies and compare the indications and outcomes with Kpros in the Indian scenario. Although the indications have significantly expanded over the years and the complications have reduced with modifications in design and postoperative regimen, these are procedures that require an exclusive setup, and a commitment toward long-term follow-up and post-Kpro care. The last decade has seen a surge in the number of Kpro procedures performed worldwide as well as in India. There is a growing need in our country among ophthalmologists to be aware of the indications for Kpro to facilitate appropriate referral as well as of the procedure to enable basic evaluation during follow-ups in case the need arises, and among corneal specialists interested to pursue the field of Kpros in understanding the nuances of these surgeries and to make a judicious decision regarding patient and Kpro selection and more importantly deferral.
Topics: Artificial Organs; Blindness; Cornea; Corneal Diseases; Humans; India; Prostheses and Implants
PubMed: 29676302
DOI: 10.4103/ijo.IJO_22_18 -
WMJ : Official Publication of the State... Aug 2017
Topics: Aged, 80 and over; Blindness; Female; Humans; Laos; Refugees; Shamanism; Thailand
PubMed: 29323830
DOI: No ID Found