Community Eye Health Journal

News and notices. Comm Eye Health Vol. 17 No. 49 2004. March 01, 2004

Abstracts

Strengthening capacity in developing countries for evidence-based public health: the data for decision-making project

M Pappaioanou, M Malison, K Wilkins, B Otto, RA Goodman, RE Churchill, M White, SB Thacker

Public Health officials and the communities they serve need to: identify priority health problems; formulate effective health policies; respond to public health emergencies; select, implement, and evaluate cost-effective interventions to prevent and control disease and injury; and allocate human and financial resources. Despite agreement that rational, data-based decisions will lead to improved health outcomes, many public health decisions appear to be made intuitively or politically. During 1991-1996, the US Centers for Disease Control and Prevention implemented the US Agency for International Development funded Data for Decision-Making (DDM) Project. DDM goals were to: (a) strengthen the capacity of decision makers to identify data needs for solving problems and to interpret and use data appropriately for public health decisions; (b) enhance the capacity of technical advisors to provide valid, essential, and timely data to decision makers clearly and effectively; and (c) strengthen health information systems (HISs) to facilitate the collection, analysis, reporting, presentation, and use of data at local, district, regional, and national levels.

Assessments were conducted to identify important health problems, problem-driven implementation plans with data-based solutions as objectives were developed, interdisciplinary, in-service training programs for mid-level policy makers, program managers, and technical advisors in applied epidemiology, management and leadership, communications, economic evaluation, and HISs were designed and implemented, national staff were trained in the refinement of HISs to improve access to essential data from multiple sources, and the effectiveness of the strategy was evaluated. This strategy was tested in Bolivia, Cameroon, Mexico, and the Philippines, where decentralization of health services led to a need to strengthen the capacity of policy makers and health officers at sub-national levels to use information more effectively. Results showed that the DDM strategy improved evidence-based public health. Subsequently, DDM concepts and practices have been institutionalized in participating countries and at CDC.

Reprinted courtesy of: Soc Sci Med 2003; 57: 1925-37

Low vision and blindness in adults in Gurage Zone, central Ethiopia

M Melese, W Alemayehu, S Bayu, T Girma, T Hailesellasie, R Khandekar, A Worku, P Courtright /h3>

AIM: To determine the magnitude and causes of low vision and blindness in the Gurage zone, central Ethiopia.

METHODS: A cross sectional study using a multistage cluster sampling technique as used to identify the study subjects. Visual acuity was recorded for all adults 40 years and older. Subjects who had a visual acuity of <6/18 were examined by an ophthalmologist to determine the cause of low vision or blindness.

RESULTS: From the enumerated population, 2693 (90.8%) were examined. The prevalence of blindness (<3/60 better eye presenting vision) was 7.9% (95% CI 6.9 to 8.9) and of low vision (6/24-3/60 better eye presenting vision) was 12.1% (95% CI 10.9 to 13.3). Monocular blindness was recorded in 16.3% of the population. Blindness and low vision increased with age. The odds of low vision and blindness in women were 1.8 times that of the men. The leading causes of blindness were cataract (46.1%), trachoma (22.9%), and glaucoma (7.6%). While the prevalence of vision reducing cataract increased with age, the prevalence of trachoma related vision loss did not increase with age, suggesting that trichiasis related vision loss in this population might not be cumulative.

CONCLUSION: The magnitude of low vision and blindness is high in this zone and requires urgent intervention, particularly for women. Further investigation of the pattern of vision loss, particularly as a result of trachomatous trichiasis, is warranted.

Reprinted courtesy of: Br J Ophthalmol 2003; 87: 677-80

A critical review of the SAFE strategy for the prevention of blinding trachoma

H Kuper, J Buchan, A Foster, AW Solomon, M Zondervan, D Mabey

Trachoma is an ocular disease caused by repeated infection with Chlamydia trachomatis . It is the leading cause of infectious blindness globally, responsible for 5.9 million cases of blindness. Although trachomatous blindness is untreatable, it is eminently possible to prevent and the World Health Organization promotes the use of the SAFE strategy (surgery to treat end-stage disease, antibiotics to reduce the reservoir of infection, facial cleanliness, and environmental improvement to reduce transmission of C trachomatis) for this purpose. In this review we have assessed the evidence base supporting the elements of the SAFE strategy. We find strong support for the efficacy of the surgery and antibiotics components, although the optimal antibiotic regimens have not yet been established. The evidence for an effect of health education andenvironmental improvement is weaker, and depends mostly on cross-sectional observational studies.

Reprinted courtesy of: Lancet Infect Dis 2003; 3: 372-81

Azithromycin treatment coverage in Tanzanian children using community volunteers

M Lynch, B Munoz , HA Mkocha, S West, KD Frick/h3>

Purpose: To determine which of two village-based strategies was more effective at recruiting residents for a trachoma mass treatment campaign.

Methods: The two strategies were to use either village government personnel to recruit residents for treatment, or to solicit interested community volunteers to recruit residents. Three villages were assigned to each strategy, and the outcome measured was treatment coverage of individuals, groups and the villages.

Results: Self-selected community volunteers were significantly more effective than village government personnel in recruit-ing villagers for antibiotic treatment (p<.0001). The differences were strongest for the group at highest risk for active trachoma, pre-school children; 73% of children in community volunteer villages were treated, compared to 63% in village government villages (p<.05). Children in villages using community volunteers and from larger families were more likely to be treated.

Conclusion: These findings support using motivated community volunteers, rather than traditional government workers, for mass treatment campaigns where high coverage is necessary.

Reprinted courtesy of: Ophthalmic Epidemiol 2003; 10: 167-75.

Barriers to accessing low vision services

TL Pollard, JA Simpson, EL Lamoureux, JE Keeffe

AIM: To investigate barriers to acces-sing low vision services in Australia.

METHODS: Adults with a vision impairment (<6/12 in the better eye and/or significant visual field defect), who were current patients at the Royal Victorian Eye and Ear Hospital (RVEEH), were interviewed. The questions investigated self-perceived vision difficulties, duration of vision loss and satisfaction with vision and also examined issues of awareness of low vision services and referral to services. Focus groups were also conducted with vision impaired (<6/12 in the better eye) patients from the RVEEH, listeners of the Radio for the Print Handicapped and peer workers at Vision Australia Foundation. The discussions were recorded and transcribed.

RESULTS: The questionnaire revealed that referral to low vision services was associated with a greater degree of vision loss (p = 0.002) and a greater self-perception of low vision (p = 0.005) but that referral was not associated with satisfaction (p = 0.144) or difficulties related to vision (p = 0.169). Participants with mild and moderate vision impairment each reported similar levels of difficulties with daily activities and satisfaction with their vision (p > 0.05). However, there was a significant difference in the level of difficulties experienced with daily activities between those with mild-moderate and severe vision impairment (p < 0.05). The participants of the focus groups identified barriers to accessing low vision services related to awareness of services among the general public and eye care professionals, understanding of low vision and the services available, acceptance of low vision, the referral process, and transport.

CONCLUSION: In addition to the expected difficulties with lack of awareness of services by people with low vision, many people do not understand what the services provide and do not identify themselves as having low vision. Knowledge of these barriers, from the perspective of people with low vision, can now be used to guide the development and content of future health-promotion campaigns.

Reprinted courtesy of: Ophthalmic Physiol Opt 2003; 23: 321-27

Causes of low vision and blindness in rural Indonesia

Saw SM, Husain R, Gazzard GM, Koh D, Widjaja D, Tan DT

AIM: To determine the prevalence rates and major contributing causes of low vision and blindness in adults in a rural setting in Indonesia.

METHODS: A population based prevalence survey of adults 21 years or older (n=989) was conducted in five rural villages and one provincial town in Sumatra, Indonesia. One stage household cluster sampling procedure was employed where 100 households were randomly selected from each village or town. Bilateral low vision was defined as habitual VA (measured using tumbling “E” logMAR charts) in the better eye worse than 6/18 and 3/60 or better, based on the WHO criteria. Bilateral blindness was defined as habitual VA worse than 3/60 in the better eye. The anterior segment and lens of subjects with low vision or blindness (both unilateral and bilateral) (n=66) were examined using a portable slit lamp and fundus examination was performed using indirect ophthalmoscopy.

RESULTS: The overall age adjusted (adjusted to the 1990 Indonesia census population) prevalence rate of bilateral low vision was 5.8% (95% confidence interval (CI) 4.2 to 7.4) and bilateral blindness was 2.2% (95% CI 1.1 to 3.2). The rates of low vision and blindness increased with age. The major contributing causes for bilateral low vision were cataract (61.3%), uncorrected refractive error (12.9%), and amblyopia (12.9%), and the major cause of bilateral blindness was cataract (62.5%). The major causes of unilateral low vision were cataract (48.0%) and uncorrected refractive error (12.0%), and major causes of unilateral blindness were amblyopia (50.0%) and trauma (50.0%).

CONCLUSIONS: The rates of habitual low vision and blindness in provincial Sumatra, Indonesia, are similar to other developing rural countries in Asia. Blindness is largely preventable, as the major contributing causes (cataract and uncorrected refractive error) are amenable to treatment.

Reprinted courtesy of: Br J Ophthalmol 2003; 87: 1075-78

Prevalence and causes of blindness and visual impairment in Bangladeshi adults: results of the National Blindness and Low Vision Survey of Bangladesh

BP Dineen, RR Bourne, SM Ali, DM Huq, GJ Johnson

AIM: To determine the age, sex, and cause specific prevalences of blindness and visual impairment in adults 30 years of age and older in Bangladesh.

METHODS: A nationally representative sample of 12 782 adults 30 years of age and older was selected based on multistage, cluster random sampling with probability proportional to size procedures. The breakdown of the cluster sites was proportional to the rural/urban distribution of the national population. The examination protocol consisted of an interview, visual acuity (VA) testing, autorefraction, and optic disc examination on all subjects. Corrected VA retesting, cataract grading, and a dilated fundal examination were performed on all visually impaired subjects. The definitions of blindness (<3/60) and low vision (<6/12 to >or=3/60) were based on the presenting visual acuity in the better eye. The World Health Organization/Prevention of Blindness proforma and its classification system for identifying the main cause of low vision and blindness for each examined subject was used.

RESULTS: In total, 11 624 eligible subjects were examined (90.9% response rate) across the 154 cluster sites. A total of 162 people were bilaterally blind (1.53% age standardised prevalence) while a further 1608 subjects (13.8%) had low vision (<6/12 VA) binocularly. Visual acuity was >6/12 in the “better eye” in the remaining 9854 subjects (84.8%); however, 748 of these people had low vision in the fellow eye. The main causes of low vision were cataract (74.2%), refractive error (18.7%), and macular degeneration (1.9%). Cataract was the predominant cause (79.6%) of bilateral blindness followed by uncorrected aphakia (6.2%) and macular degeneration (3.1%).

CONCLUSIONS: There are an estimated 650 000 blind adults (95% CI 552 175 to 740 736) aged 30 and over in Bangladesh, the large majority of whom are suffering from operable cataract. This survey indicates the need for the development and implementation of a national plan for the delivery of effective eye care services, aimed principally at resolving the large cataract backlog and the inordinate burden of refractive error.

Reprinted courtesy of: Br J Ophthalmol 2003; 87: 820-28

Causes of severe visual impairment and blindness in children in schools for the blind in Ethiopia

AB Kello, C Gilbert

AIMS: To determine the causes of severe visual impairment and blindness in children in schools for the blind in Ethiopia, to aid in planning for the prevention and management of avoidable causes.

METHODS: Children attending three schools for the blind in Ethiopia were examined during April and May 2001 using the standard WHO/PBL eye examination record for children with blindness and low vision protocol. Data were analysed for those children aged less than 16 years using the EPI-INFO-6 programme.

RESULTS: Among 360 pupils examined, 312 (96.7%) were aged <16 years. Of these children, 295 (94.5%) were blind or severely visually impaired. The major anatomical site of visual loss was cornea/phthisis (62.4%), followed by optic nerve lesions (9.8%), cataract/aphakia (9.2%), and lesions of the uvea (8.8%). The major aetiology was childhood factors (49.8%). The aetiology was unknown in 45.1% of cases. 68% of cases were considered to be potentially avoidable.

CONCLUSIONS: Vitamin A deficiency and measles were the major causes of severe visual impairment/blindness in children in schools for the blind in Ethiopia. The majority of causes acquired during childhood could be avoided through provision of basic primary healthcare services.

Reprinted courtesy of: Br J Ophthalmol 2003; 87: 526-30.

Support for patients losing sight

S Trauzettel-Klosinski, GA Hahn

This overview on support of patients losing sight is based on a literature survey regarding reading disabilities and orientation and on results of experience trials performed at the University Eye Clinic Tubingen. In reading disorders, the main goal of rehabilitation is to regain or maintain the ability to read newspaper print. The fundament of rehabilitation is the use of optical and electronical devices and the application of specially designed training programs. The ability of a person with low vision to achieve successful orientation and mobility rehabilitation depends on residual vision, posture and balance, body image, auditory and tactile abilities, intelligence and personality. Rehabilitation efforts focus on the enhancement of residual vision applying magnifying contrast-enhancing and photomultiplying devices. The main pillar of orientation and mobility rehabilitation is a training especially designed for the patient’s needs. Rehabilitation efforts must be tailored to the type of vision loss and to specific functional implications—the success rate is high. An optimal fitting of the required spectrum of low vision aids should be provided to the patient, and importantly, professional teaching and training is recommended. Activities of daily living, orientation and mobility, and psychological concerns must be addressed. Close cooperation with other branches of rehabilitation is essential.

Reprinted courtesy of: Dev Ophthalmol 2003;37:199-214

The development of the LV Prasad-Functional Vision Questionnaire: a measure of functional vision performance of visually impaired children

VK Gothwal, J E Lovie-Kitchin, R Nutheti

PURPOSE: To develop a reliable and valid questionnaire (the LV Prasad-Functional Vision Questionnaire, LVP-FVQ) to assess self-reported functional vision problems of visually impaired school children.

METHODS: The LVP-FVQ consisting of 19 items was administered verbally to 78 visually impaired Indian school children aged 8 to 18 years. Responses for each item were rated on a 5-point scale. A Rasch analysis of the ordinal difficulty ratings was used to estimate interval measures of perceived visual ability for functional vision performance.

RESULTS: Content validity of the LVP-FVQ was shown by the good separation index (3.75) and high reliability scores (0.93) for the item parameters. Construct validity was shown with good model fit statistics. Criterion validity of the LVP-FVQ was shown by good discrimination among subjects who answered “seeing much worse” versus “as well as”; “seeing much worse” versus “as well as/a little worse” and “seeing much worse” versus “a little worse,” compared with their normal-sighted friends. The task that required the least visual ability was “walking alone in the corridor at school”; the task that required the most was “reading a textbook at arm’s length.” The estimated person measures of visual ability were linear with logarithm of the minimum angle of resolution (logMAR) acuity and the binocular high contrast distance visual acuity accounted for 32.6% of the variability in the person measure.

CONCLUSIONS: The LVP-FVQ is a reliable, valid, and simple questionnaire that can be used to measure functional vision in visually impaired children in developing countries such as India.

Reprinted courtesy of: Invest Ophthalmol Vis Sci 2003; 44: 4131-39

Modification of the no-stitch technique in extracapsular cataract extraction by a single radial suture. Effect on postoperative astigmatism

H Haberle, N Anders, S Drosch, DT Pham, J Wollensak

Self-sealing intrascleral wound construction with a trapezoidal 12-mm incision for extracapsular cataract extraction and implantation of a standard PMMA IOL with a 6.5-mm optical diameter using the no-stitch technique has been well established at our clinic since 1991. This technique allows cataract surgery in a nearly closed system. In consideration of our earlier results, the no-stitch technique was modified by a single perpendicular suture in the middle of the 12-mm incision to reduce postoperative induced astigmatism further. We examined 200 consecutive patients 6 months after surgery (no-stitch vs one-stitch wound closure). The preoperative average astigmatism was 0.86 +/- 0.68 D (1.01 +/- 0.95 D). Preoperatively 37% (47%) of the eyes had With the Rule Astigmatism and 47% (39%) Against the Rule Astigmatism. Six months after surgery 10% (8%) of the cases showed With the Rule Astigmatism and 72% (65%) Against the Rule Astigmatism. Induced astigmatism was stabilized to 1.43 +/- 0.87 D (2.11 +/-1.43 D). Compared with sutureless wound closure, the one-stitch technique had no long-term effect on the axes of astigmatism but significantly diminished induced astigmatism about 0.5 D.

Reprinted courtesy of: Ophthalmologe 1995; 92: 261-65 [Article in German]