Prevalence and causes of visual impairment in diabetic patients in Tunisia, North Africa.

PURPOSE: To investigate the prevalence and causes of blindness and partial sight among a population of Tunisian diabetic patients. METHODS: A cross-sectional study of 2320 randomly identified patients with diabetes mellitus. Patient's characteristics as well as data from the last ophthalmic examination were reviewed. RESULTS: Of all patients examined, 60.2% were females and 39.8% were males. Mean age of patients was 54.5 years. Mean duration of diabetes was 7.6 years. Diabetic retinopathy (DR) was recorded in 26.3% of patients, and was proliferative in 3.4% of patients. The prevalence of visual impairment was 22.2%, with 4.4% patients legally blind and 17.8% partially sighted. Visual impairment was significantly associated with age ≥60 years (P<0.001), duration of diabetes >10 years (P<0.001), body mass index >25 (P=0.014), hypertension (P<0.001), heart disease (P<0.001), peripheral neuropathy (P=0.03), vegetative neuropathy (P=0.002), macroalbuminuria (P<0.001), cataract (P<0.001), DR (P<0.001), diabetic macular edema (P<0.001), open angle glaucoma (P<0.001), intravitreal hemorrhage (P<0.001), rubeosis iridis (P<0.001), neovascular glaucoma (P<0.001), and tractional retinal detachment (P<0.001). CONCLUSION: The current report is the largest study of DR in North African region. It provides a baseline data against which future progress can be assessed. Screening and treatment can greatly reduce the incidence of visual impairment due to diabetes.

Prevalence and causes of vision loss in Southeast Asia and Oceania: 1990-2010.

BACKGROUND: To assess prevalence and causes of vision impairment in Southeast Asia and Oceania in 1990 and 2010. METHODS: Based on a systematic review of medical literature, prevalence of moderate and severe vision impairment (MSVI; presenting visual acuity <6/18 but ≥3/60 in the better eye) and blindness (presenting visual acuity <3/60) was estimated for 1990 and 2010. RESULTS: In Oceania, the age-standardised prevalence of blindness and MSVI did not decrease significantly (1.3% to 0.8% and 6.6% to 5.1%) respectively, but in Southeast Asia, blindness decreased significantly from 1.4% to 0.8%, a 43% decrease. There were significantly more women blind (2.18 million) compared with men (1.28 million) in the Southeast Asian population in 2010, but no significant gender differences in MSVI in either subregion. Cataract was the most frequent cause of blindness in Southeast Asia and Oceania in 1990 and 2010. Uncorrected refractive error, followed by cataract, macular degeneration, glaucoma and diabetic retinopathy were the most common causes for MSVI in 1990 and 2010. With the increasing size of the older population, there have been relatively small increases in the number of blind (2%), and with MSVI (14%) in Southeast Asia, whereas increases have been greater in Oceania of 14% for blindness and of 31% for MSVI. CONCLUSIONS: The prevalence of blindness has reduced significantly from 1990 to 2010, with moderate but non-significant lowering of MSVI. Cataract and uncorrected refractive error are the main causes of vision impairment and blindness; cataract continues as the main cause of blindness, but at lower proportions.

Global cost of correcting vision impairment from uncorrected refractive error.

OBJECTIVE: To estimate the global cost of establishing and operating the educational and refractive care facilities required to provide care to all individuals who currently have vision impairment resulting from uncorrected refractive error (URE). METHODS: The global cost of correcting URE was estimated using data on the population, the prevalence of URE and the number of existing refractive care practitioners in individual countries, the cost of establishing and operating educational programmes for practitioners and the cost of establishing and operating refractive care facilities. The assumptions made ensured that costs were not underestimated and an upper limit to the costs was derived using the most expensive extreme for each assumption. FINDINGS: There were an estimated 158 million cases of distance vision impairment and 544 million cases of near vision impairment caused by URE worldwide in 2007. Approximately 47 000 additional full-time functional clinical refractionists and 18 000 ophthalmic dispensers would be required to provide refractive care services for these individuals. The global cost of educating the additional personnel and of establishing, maintaining and operating the refractive care facilities needed was estimated to be around 20 000 million United States dollars (US$) and the upper-limit cost was US$ 28 000 million. The estimated loss in global gross domestic product due to distance vision impairment caused by URE was US$ 202 000 million annually. CONCLUSION: The cost of establishing and operating the educational and refractive care facilities required to deal with vision impairment resulting from URE was a small proportion of the global loss in productivity associated with that vision impairment.

Vision 2020 - the right to sight.

The unprecedented partnership for onchocerciasis control that followed Merck's decision to donate Mectizan has inspired the formation of a global initiative for the elimination of all avoidable blindness by the year 2020. 'Vision 2020, the Right to Sight', jointly co-ordinated by the World Health Organization's Programme for the Prevention of Blindness and Deafness and the International Agency for the Prevention of Blindness, was launched in 1999. This initiative's three pillars are disease control, human resource development, and infrastructure development. Vision 2020's achievements to date include the growth of the partnership, to include more than 60 member organizations, the revitalization of prevention activities, the completion of Vision-2020 plans in 40% of all countries and a reduction not only of blindness caused by onchocerciasis but also of blindness caused by trachoma. Cataract remains the leading cause of avoidable blindness.

The impact of Vision 2020 on global blindness.

INTRODUCTION: Recent data suggest that there are 37 million blind people and 124 million with low vision, excluding those with uncorrected refractive errors. The main causes of global blindness are cataract, glaucoma, corneal scarring (from a variety of causes), age-related macular degeneration, and diabetic retinopathy. CONCLUSION: It would appear that the global Vision 2020 initiative is having an impact to reduce avoidable blindness particularly from ocular infections, but more needs to be done to address cataract, glaucoma, and diabetic retinopathy.

2002 global update of available data on visual impairment: a compilation of population-based prevalence studies.

PURPOSE: For the past 25 years, the WHO Programme for the Prevention of Blindness and Deafness has maintained a Global Data Bank on visual impairment with the purpose of storing the available epidemiological data on blindness and low vision. The Data Bank has now been updated to include studies conducted since the last update in 1994. METHODS: An extensive literature search was conducted in international and national scientific and medical journals to identify epidemiological studies that fulfilled basic criteria for inclusion in the Data Bank, namely a clearly stated definition of blindness and low vision, and prevalence rates derived from population-based surveys. Sources such as National Prevention of Blindness Programmes, academic institutions or WHO country or regional reports were also investigated. RESULTS: Two-hundred-and-eight population-based studies on visual impairment for 68 countries are reported in detail, providing an up-to-date, comprehensive compilation of the available information on visual impairment and its causes globally.

[Cataract surgery in Togo]. / La chirurgie de la cataracte au Togo.

Cataract remains a major cause of blindness in sub-Sahara and a major public health problem. Blindness prevalence in Togo is equal to 1%, more than half of it is due to cataract, while the number of cataract surgeries is low because of the lack of resources. We assessed the eye healthcare in Togo by cataract surgery. The aim was to estimate the number of cataract surgeries and the Cataract Surgery Rate (CSR) in the administrative regions. The demographic data (denominator) was collected from the Demography and Health Survey (1998) while the number of cataract surgeries (numerator) was obtained from medical registers. The Cataract Surgery Rate (CSR, operated cataracts per million) was assessed from 1995 to 2001. From 1995 to 2001, 3,885 cataract surgeries were performed. Public services predominated with 53.03% (n=2061) of the cataracts operated followed by confessional hospitals with 37.1% (n=1443) and private clinics 3.4% (n=143). Decentralised eye healthcares provided 241 cataract extractions. The University hospital centre of Lome Tokoin was the leader, with 32.5% (n=1,262) of operated cataracts followed by the confessional hospital of Glei, 27.2% (n=1,058). The average per centre per year was 43 cataract surgeries. The mean CSR was 126 and varied from 52 to 163 cataract surgeries per million people per year. There was an important concentration of cataract services in Lome where 41% (n=1,586) of cataracts were operated and the CSR was 334. The unequal distribution of cataract services (41% in Lome) leaves many regions without any resources. Since 1999, the CSR increased by 37% in 2000 and 14% in 2001. The Togolese eye healthcare system is poor and substantial further efforts are necessary to make it accessible and affordable to all those in need. This may be the way to reduce cataract surgery barriers and the unacceptable high prevalence of operable cataract blindness.

Eye healthcare services in eastern Europe: Part 1. Cataract surgery.

AIM: To describe cataract surgical services in 1998 in 12 eastern European countries and to identify their needs to reduce cataract blindness. METHODS: All inpatient eye departments in the 12 countries received a standardised questionnaire; the data obtained were further processed at the coordinating centre in Prague. RESULTS: All 458 eye departments in the region were involved. The response rate was 100%, except for Bulgaria (93%) and Romania (93%). The total number of cataract surgeries per one million inhabitants in 1998 was calculated: Belarus (800), Federation of Bosnia and Herzegovina (1275), Bulgaria (1730), the Czech Republic (4210), Estonia (2530), Hungary (3530), Latvia (1860), Lithuania (1550), Trans-Dniester Moldova (1300), Poland (1475), Romania (1260), and Slovakia (2430). Cataracts were mostly operated on by the extracapsular technique. Intracapsular extractions were frequently performed in Federation of Bosnia and Herzegovina (47%), Belarus (46%), Bulgaria (18%), and Romania (14.3%). Phacoemulsification was uncommonly used in 1998, except for the Czech Republic (86%), Estonia (50%), Slovakia (38%), and Hungary (16%). An IOL was implanted in more than 90% of patients in the Czech Republic, Estonia, Hungary, Latvia, Lithuania, and Slovakia. CONCLUSIONS: Conditions for cataract surgery in the eastern European region differ. The main barriers to cataract surgery were state budget limitations, insufficient supply of consumables, underutilisation of operating theatres, and poor detection of patients requiring surgery.

Eye healthcare services in eastern Europe: Part 2. Vitreoretinal surgical services.

AIM: To describe vitreoretinal surgical services in 1998 in 12 eastern European countries and to identify ways for their further improvement. METHODS: All inpatient eye departments in the 12 countries received a standardised questionnaire; the data obtained were processed at the international study coordinating centre in Prague. RESULTS: All 458 eye departments in the region were involved. The number of retinal detachments treated by extraocular surgery, or pars plana vitrectomy, per one million inhabitants respectively, were as follows: Belarus (52; 6), Federation of Bosnia and Herzegovina (21; 2), Bulgaria (39; 19), the Czech Republic (78; 40), Estonia (60; 17), Hungary (81; 88), Latvia (82; 36), Lithuania (68; 6), Trans-Dniester Region of Moldova (6; -), Poland (70; data not available), Romania (24; 25), and Slovakia (67; 55). The number of people per one retinal laser was assessed (in millions): Belarus (1.26), Federation of Bosnia and Herzegovina (2.23), Bulgaria (0.59), the Czech Republic (0.22), Estonia (0.24), Hungary (0.23), Latvia (0.41), Lithuania (0.62), Poland (0.36), Romania (2.25), and Slovakia (0.14). CONCLUSIONS: Conditions for posterior eye segment surgery in the central and eastern European region vary substantially. Underserved regions require (1) more eye doctors trained in surgical and laser retinal treatment; (2) improvement in screening for diabetic eye complications and retinopathy of prematurity; (3) technical equipment for places in need.

Visual impairment and blindness in Europe and their prevention.

The European region currently differs in many aspects, such as political, socioeconomic, and geographical. After substantial political changes at the beginning of the 1990s, the majority of central and eastern European countries started to rebuild their healthcare systems. It is apparent that eastern Europe represents a highly diverse region where the difference among countries broadens year after year. In highly industrialised countries of Europe, the leading causes of childhood serious visual loss are lesions of the central nervous system, congenital anomalies and retinal disorders. In the middle income countries of Europe, congenital cataract, glaucoma and, mainly, retinopathy of prematurity are highly expressed. The major cause of serious visual loss in adults in industrialised countries is age related macular degeneration. The other conditions comprise cataract, glaucoma, diabetic retinopathy, and uncorrected/uncorrectable refractive errors, along with low vision. In people of working age, diabetic retinopathy, retinopathy pigmentosa, and optic atrophy are the most frequently reported causes of serious visual loss. In the middle income countries of Europe, advanced cataract, glaucoma, and diabetic retinopathy are more frequently observed.

Blindness prevention programmes: past, present, and future.

Blindness and visual impairment have far-reaching implications for society, the more so when it is realized that 80% of visual disability is avoidable. The marked increase in the size of the elderly population, with their greater propensity for visually disabling conditions, presents a further challenge in this respect. However, if available knowledge and skills were made accessible to those communities in greatest need, much of this needless blindness could be alleviated. Since its inception over 50 years ago, and beginning with trachoma control, WHO has spearheaded efforts to assist Member States to meet the challenge of needless blindness. Since the establishment of the WHO Programme for the Prevention of Blindness in 1978, vast strides have been made through various forms of technical support to establish national prevention of blindness programmes. A more recent initiative, "The Global Initiative for the Elimination of Avoidable Blindness" (referred to as "VISION 2020--The Right to Sight"), launched in 1999, is a collaborative effort between WHO and a number of international nongovernmental organizations and other interested partners. This effort is poised to take the steps necessary to achieve the goal of eliminating avoidable blindness worldwide by the year 2020.

[Acanthamoeba keratitis: search for a healthy carrier in Mali]. / Kératites à Acanthamoeba: recherche d'un portage oculaire sain au Mali.

The first cases of Acanthamoeba keratitis in Africa were reported in 1990 at the Institute of African Tropical Ophthalmology (IOTA) in Bamako, Mali. From 1990 to 1995, a total of 22 cases of corneal ulcers involving Acanthamoeba sp. were diagnosed at the IOTA. To improve our understanding of the epidemiological characteristics of these lesions in tropical areas, we attempted to identify healthy carriers of Acanthamoeba sp. by studying the normal eye flora of 149 patients examined at the IOTA in February 1996. Acanthamoeba sp. was not detected in any sample. Fungi were detected in 22.15 p. 100 of the samples. Thus, it would appear that, unlike fungi, Acanthamoeba sp. is not present in normal eye flora in Mali. This findings suggests that the occurrence of Acanthamoeba in corneal ulcers is not an accident. Our results also emphasize the need for screening to detect Acanthamoeba in developing countries such as Mali. However, further study will be needed to confirm these findings in a larger group of subjects more closely matched with the patients presenting the corneal ulcers diagnosed at the IOTA, especially with regard to geographical origin.

Urbanisation and vitamin A deficiency in children: comparison between a traditional district and a new settlement in Mali.

OBJECTIVES: The purpose of this study was to assess the vitamin A status of pre-school urban children and to compare the situation between a traditional district and a new settlement after two decades of intense urbanisation. SUBJECTS AND METHODS: A cross-sectional stratified survey was carried out in Bamako, Mali, on a representative sample of children (aged 4-6 years). 532 children were involved from a traditional district and 453 from a new settlement (NS). The vitamin A status was assessed by: clinical indicators (ophthalmic examination), subclinical indicators (questionnaire looking for night blindness, impression cytology with transfer test (ICT), modified relative dose response test (MRDR), and a diet inquiry about vitamin A intakes. Acute malnutrition was assessed by a weight/height measure. RESULTS: In both districts, all the clinical indicators were below the WHO criteria that define a public health problem. Both the ICT test, respectively 19 and 21% of abnormal tests, and the MRDR, 67.3 and 73.1% of tests > or = 0.06, indicated a subclinical vitamin A deficiency as defined by WHO thresholds. During the preceding week only four children in NS had consumed vitamin A-rich food less than seven times. No significant difference between the two districts was found either for clinical or subclinical indicators (p > 0.5). CONCLUSION: Despite a rapid urbanisation, the vitamin A status of the children seemed to be rather homogeneous among the different districts. The population remained vulnerable with peripheral depletion and low hepatic stores of vitamin A. The urban children should be carefully monitored regarding vitamin A status.

[Progress in the control of world blindness and future perspectives]. / Progrès réalisés dans la lutte contre la cécité dans le monde et perspectives d'avenir.

Worldwide, there are approximately 180 million severely visually impaired people, of whom some 45 million are blind. Cataract remains the major cause of blindness, especially in the less developed countries. Substantial improvements have been achieved in the control of blinding diseases, mainly in respect of onchocerciasis and xerophthalmia. More recently, a WHO alliance for the eradicating of trachoma by the year 2020 has been set up. In Africa, the situation remains critical in spite of significant improvements in the training of eye care personnel and the implementation of new eye care facilities. If no additional action is taken, the number of blind from cataract will steadily increase, mainly because of population growth and aging. Substantial further efforts should be made to make appropriate eye care accessible and affordable to all those in need.

Ganciclovir ophthalmic gel (Virgan; 0.15%) in the treatment of herpes simplex keratitis.

PURPOSE: Ganciclovir is a broad-spectrum virustatic agent. Its efficacy and safety after ocular application have been demonstrated in studies of herpetic keratitis in rabbits. Two strengths of ganciclovir gel (0.05 and 0.15%) were compared with 3% acyclovir ointment in the treatment of superficial herpes simplex keratitis in humans. METHODS: Two multicenter randomized clinical trials were carried out in Africa (Trial 1) and Europe (Trial 2). Sixty-seven patients (Trial 1) and 37 patients (Trial 2) from herpetic ulceration were recruited. RESULTS: The results showed no statistically significant difference between the treatment groups, although the healing rates tended to be better in the group receiving 0.15% ganciclovir gel, with healing rates of 85% (Trial 1) and 83% (Trial 2) as compared with 72% (Trial 1) and 71% (Trial 2) in the group receiving acyclovir ointment. Local tolerance was found to be superior with the gel formulation of ganciclovir with fewer complaints of discomfort (stinging, burning) or blurred vision after application of the drug. Systemic absorption of the drug was low. No hematologic changes were detected. CONCLUSIONS: These findings support the efficacy of ganciclovir gel in the treatment of ulcerative herpes simplex keratitis and demonstrate its superior local tolerance when compared with acyclovir ointment.

[Ophthalmologic complications due to human immunodeficiency virus infection at Bamako (Mali)]. / Complications ophtalmologiques de l'infection par les virus de l'immunodéficience humaine (VIH) à Bamako (Mali).

AIDS ocular complications have been researched in 70 hospitalised patients in the two main hospitals of Bamako (Mali) during one year (1992-1993). Men were predominant (sex ratio 1.6). HIV1 infections (67%) were most frequent than HIV1 + HIV2 (21.4%) or HIV2 infections (11.4%). Most of the patients were on the WHO's clinical stage III; 34% of them had ocular complications, quite often non infectious: cotonous nodules (10%), vascularitis (5.7%) and retineous haemorrhages (4.3%). Ocular opportunistic infections were rare: only one case of toxoplasmic chorio-retinitis was reported. Ocular complications were observed with all types of HIV. Vascular abnormalities were observed in the stage II or IV of AIDS and seemed, in Bamako, as a serious sign during the AIDS course.