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Lewallen S. Prevention of blindness in leprosy: an overview of the relevant clinical and programme-planning issues. Annals of Tropical Medicine & Parasitology 2016. [DOI: 10.1080/00034983.1997.11813148] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Okwen M, Lewallen S, Courtright P. Primary eye care skills scores for health workers in routine and enhanced supervision settings. Public Health 2013; 128:96-100. [PMID: 24359760 DOI: 10.1016/j.puhe.2013.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 10/03/2013] [Accepted: 10/11/2013] [Indexed: 11/17/2022]
Abstract
INTRODUCTION Primary health care in Tanzania is provided at two types of health units, the dispensary and the health centre. Theoretically, primary health workers (with knowledge of primary eye care [PEC]) are ideally placed to identify people in need of eye care services. In Tanzania, they are expected to be able to identify, treat, or correctly refer a number of eye conditions including cataract, trauma, presbyopia, and the 'red eye'. They are also expected to be able to measure visual acuity correctly and to educate the community about prevention. OBJECTIVES The objective was to determine the effect of enhanced supervision of health workers on PEC knowledge and skills in Kilimanjaro Region, Tanzania. STUDY DESIGN This was a quasi-experimental, cluster randomized intervention study of an enhanced supervisory method compared to a routine supervisory method; 36 dispensaries were randomly allocated into the two groups. PARTICIPANTS Health workers based at government dispensaries in Mwanga District. DATA COLLECTION Participants were interviewed pre and post intervention and the information was recorded using a standardized pretested questionnaire. RESULTS Mean scores of knowledge in healthcare workers was higher in the intervention group (score = 6.43, 80.4% improvement) compared to the non-intervention group (score = 4.71, 58.9% improvement). The ability to describe and demonstrate vision testing was better (score = 1.8) in the enhanced supervision group compared to the routine supervision group (score = 0.88, P = 0.03). There was a high level of attrition (24%) within one year from the time of baseline survey, especially amongst clinical officers (44%). CONCLUSION During the pilot study, enhanced supervision improved PEC knowledge and skills of health workers compared to health workers with routine supervision. RECOMMENDATIONS Training in PEC needs revision to become more practicum-based. There is need to revise supervision guidelines (to be skills-based) and the supervision skills of district eye coordinators (DECs) need to be enhanced. There is a huge need to improve governance (accountability and rule of law) of health staff.
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Affiliation(s)
- M Okwen
- Department of Ophthalmology, KCM College, Tumaini University, Moshi, Tanzania
| | - S Lewallen
- Kilimanjaro Centre for Community Ophthalmology, PO Box 2254, Moshi, Tanzania
| | - P Courtright
- Kilimanjaro Centre for Community Ophthalmology, PO Box 2254, Moshi, Tanzania.
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Courtright P, Seneadza A, Mathenge W, Eliah E, Lewallen S. Primary eye care in sub-Saharan African: do we have the evidence needed to scale up training and service delivery? Ann Trop Med Parasitol 2010; 104:361-7. [PMID: 20819303 DOI: 10.1179/136485910x12743554760225] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The models for addressing the delivery of an eye-care service in sub-Saharan Africa have seen considerable revision in the last 30 years, and the on-going challenges, as well as the future needs, will probably require many more changes and new systems. There is a need to assess the different models that are currently employed, in order to ensure that all potential contributions to the elimination of avoidable blindness are used; the evolving concept of primary eye care (PEC) requires such assessment. For the current review, the published literature on eye care provided by general front-line healthworkers was screened for articles that provided evidence of the impact of such PEC on the general delivery of eye care in sub-Saharan Africa. Of the 103 relevant articles detected, only three provided evidence of the effectiveness of PEC and the authors of all three of these articles suggested that such eye care was not meeting the needs or expectations of the target populations, the trainers, or programmes of eye care. Among the main problems identified were a lack of a clear definition of the scope of practice for PEC, the need for clarifying the specific skills that a front-line healthworker could perform correctly, and the changing needs and expectations for the delivery of an eye-care service in Africa. If PEC is to become adequately grounded in Africa, the generation of further evidence of the effectiveness and limitations of such care would be a prudent move.
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Affiliation(s)
- P Courtright
- Kilimanjaro Centre for Community Ophthalmology, Good Samaritan Foundation, PO Box 2254, Moshi, Tanzania.
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Shirima S, Lewallen S, Kabona G, Habiyakare C, Massae P, Courtright P. Estimating numbers of blind children for planning services: findings in Kilimanjaro, Tanzania. Br J Ophthalmol 2009; 93:1560-2. [PMID: 19666927 DOI: 10.1136/bjo.2009.161083] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM Childhood blindness is included in the VISION 2020 initiative. However, childhood blindness is rare, so there is limited population-based evidence to assist with the planning of services. We carried out a survey of childhood blindness in Kilimanjaro Region, Tanzania, to generate information needed for planning eye care services. METHODS The study was carried out in parallel with a Rapid Assessment of Avoidable Blindness (RAAB) survey. Villages within Kilimanjaro Region were selected on a probability-proportional-to-size basis. Key informants in each village were trained to identify children with any vision problems; a visiting team assessed the children to determine visual status and arranged for further assessment as needed at hospital. The files of children at schools for the blind in the Region were reviewed to identify children in schools from the selected study villages. RESULTS Among the 95 040 children in the 72 villages sampled, 13 children were identified as blind; an additional three children were found in the schools for the blind. The prevalence of blindness was 0.17 per 1000 children; the causes of blindness varied but there was no vitamin A- or measles-related corneal blindness and only one case of unoperated cataract. DISCUSSION The low prevalence of blindness in children suggests that efforts at reducing childhood blindness in Kilimanjaro Region have been effective. Planners there should focus on community-based approaches to ensure that blind children have appropriate rehabilitation services and educational placements. While it remains impractical to carry out large childhood blindness surveys, this approach attached to a RAAB survey may be useful for generating information for planning services.
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Affiliation(s)
- S Shirima
- Kilimanjaro Centre for Community Ophthalmology, KCM College/Tumaini University, Moshi, Tanzania
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Tumwesigye C, Msukwa G, Njuguna M, Shilio B, Courtright P, Lewallen S. Inappropriate enrollment of children in schools for the visually impaired in east Africa. ACTA ACUST UNITED AC 2009; 29:135-9. [PMID: 19460267 DOI: 10.1179/146532809x440752] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
BACKGROUND Many visually impaired children can learn to read print with appropriate training and simple visual aids. This may allow them to attend normal schools and to be integrated into society, which has lifelong benefits. Yet, in Africa, many visually impaired children are enrolled in special schools and taught only Braille. The purpose of this analysis was to document the extent of inappropriate enrollment of visually impaired children in special schools and annexes for the blind in four African countries. METHODS Schools were selected through a population-proportional-to-size method so that they would represent all children attending special schools in Kenya, Malawi, Tanzania and Uganda. Children were examined by ophthalmologists trained in standardised methods to determine visual acuity and the cause of decreased acuity. RESULTS Of 1062 children examined in special schools and annexes for the blind, 361 (34%, 95% CI 31.2, 36.8) had visual acuity >or=6/60; the most common cause of visual impairment was retinal disease. Of the 120 children with normal vision (>or=6/18), 69 (57.5%) had two normal eyes, 21 (17.5%) had an obvious ocular disfigurement in the fellow eye and 10 (8.4%) had had successful cataract surgery. CONCLUSIONS In these countries, many children are placed inappropriately in special schools and annexes for the blind. The reasons are multiple and to rectify the situation will require advocacy and cooperation between ministries of health and education.
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Affiliation(s)
- C Tumwesigye
- Department of Ophthalmology, Mulago Hospital, Kampala, Uganda
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Jefferis JM, Bowman RJ, Hassan HG, Hall AB, Lewallen S. Use of Cataract Services in Eastern Africa—A Study from Tanzania. Ophthalmic Epidemiol 2009; 15:62-5. [DOI: 10.1080/09286580701624725] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Courtright P, Williams T, Gilbert C, Kishiki E, Shirima S, Bowman R, Lewallen S. Measuring cataract surgical services in children: an example from Tanzania. Br J Ophthalmol 2008; 92:1031-4. [PMID: 18653593 DOI: 10.1136/bjo.2007.136168] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Childhood cataract is becoming increasingly recognised as a priority for reducing childhood blindness in developing countries. However, there have been no standard methods to monitor progress in providing this service, besides sporadic reports of surgeries performed. METHODS Information on all children receiving surgery for congenital/developmental cataract in the two Child Eye Health Tertiary Facilities (CEHTF) in Tanzania was collected for 2004-6. An annual childhood cataract surgical rate (CCSR) was calculated per region. Male-to-female ratios were also generated by region of residence. RESULTS Overall, the CCSR (2006) in Tanzania was 9.9 per million population, ranging from 32.3 for regions where CEHTF are located to 5.4 for regions not adjacent to CEHTF regions. There were, on average, 148 boys for every 100 girls receiving surgery. CONCLUSION Practical application of a measure of service delivery for childhood cataract has been useful in identifying gaps in utilisation of existing services by region as well as by gender. Testing in other settings would be helpful. An apparent inequity in use of services by girls requires attention.
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Affiliation(s)
- P Courtright
- Kilimanjaro Centre for Community Ophthalmology, Tumaini University, PO Box 2254, Moshi, Tanzania.
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Chibuga E, Massae P, Geneau R, Mahande M, Lewallen S, Courtright P. Acceptance of cataract surgery in a cohort of Tanzanians with operable cataract. Eye (Lond) 2007; 22:830-3. [PMID: 17277747 DOI: 10.1038/sj.eye.6702736] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND In spite of recent increases in the number of surgeries carried out within some hospitals and programmes in sub-Saharan Africa, there are indications that the acceptance of cataract surgery remains quite low. METHODS We conducted a population-based prospective (cohort) study of cataract patients from 12 villages in Hai district of Kilimanjaro region, Tanzania. Those identified with operable cataract were informed of the regular community programmes (within 5 km) in place providing transportation and high-quality surgery. At years 1 and 2 after the survey, we traced the patients to determine uptake of cataract surgery. RESULTS Among patients eligible for surgery (128), 31 could not be followed up after 1 year due to deaths, moving, and refusal. Among the remaining patients, 18 accepted surgery in the first year and four accepted in the second year. Among these 22 patients, only five were blind or with severe visual impairment. The most elderly were those least likely to accept surgery. DISCUSSION Even with bridging strategies in place to make cataract surgery accessible and affordable, the uptake of cataract surgery remains low. Strategies aimed to identifying and referring all patients recognizing vision loss as a personal disability rather than using predefined vision cutoffs will likely be most successful in reducing the burden of vision loss due to cataract.
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Affiliation(s)
- E Chibuga
- Kilimanjaro Christian Medical College, Moshi, Tanzania
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Beare NAV, Riva CE, Taylor TE, Molyneux ME, Kayira K, White VA, Lewallen S, Harding SP. Changes in optic nerve head blood flow in children with cerebral malaria and acute papilloedema. J Neurol Neurosurg Psychiatry 2006; 77:1288-90. [PMID: 17043298 PMCID: PMC2077392 DOI: 10.1136/jnnp.2005.083956] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2005] [Revised: 06/08/2006] [Accepted: 07/13/2006] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To investigate capillary blood flow in the optic nerve head (ONH) of children with cerebral malaria. METHODS Malawian children with cerebral malaria admitted to a paediatric research ward were examined by direct and indirect ophthalmoscopy. ONH blood flow was measured using laser Doppler flowmetry (LDF) in suitable patients. Mean blood volume and velocity were obtained from 30 to 60 s recordings from the temporal ONH and used to calculate blood flow. These were compared with admission variables, funduscopic findings and disease outcomes. RESULTS 45 children with cerebral malaria had LDF recordings; 6 subsequently died and 5 survivors had neurological sequelae. 12 (27%) had papilloedema. The mean microvascular blood volume was higher in patients with papilloedema (3.28 v 2.54 arbitrary units, p = 0.002). The blood velocity correlated directly with haematocrit (r = 0.46, p = 0.001) and inversely with blood glucose (r = -0.49, p = 0.001). CONCLUSION The increase in ONH microvascular blood volume in papilloedema measured by LDF is consistent with current theories of pathogenesis of papilloedema. LDF has potential as a tool to distinguish papilloedema from pseudopapilloedematous disc swellings. The relationship between blood velocity and haematocrit may relate to levels of sequestration in cerebral malaria.
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Affiliation(s)
- N A V Beare
- St Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool L7 8XP, UK.
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Affiliation(s)
- S P Harding
- St Paul's Eye Unit, Royal Liverpool University Hospital, Prescot Street, Liverpool L7 8XP, UK.
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Abstract
BACKGROUND Knowing what rural populations are willing to pay for cataract surgery is essential if improvements in cost recovery in eye care service provision programmes are to take place. The authors sought to learn about willingness to pay for cataract surgery in two separate regions of Tanzania. METHODS Patients desiring cataract surgery were interviewed in Kilimanjaro Region and Iringa Region of Tanzania to learn how much they and their families were willing to pay for surgery and how "wealthy" (using ownership of several household objects as a proxy for wealth) the household was. RESULTS 60 cataract patients in Kilimanjaro and 49 in Iringa were interviewed. "Wealth" was significantly associated with willingness to pay in each region. The average expressed willingness to pay was 2457Tsh (SD 4534) or approximately $US2.30, which is far below the actual cost of providing the service. CONCLUSION There were significant differences in the expressed willingness to pay between Iringa and Kilimanjaro patients, which may reflect differences in the services provided in the regions. Willingness to pay may increase as the population gains familiarity and trust in the service. It may also be increased by ensuring that pricing is uniform and clearly advertised throughout regions and by educating health workers and counselling patients about the real costs of providing high quality surgery. Offering "free" services to all may result in lower expressed willingness to pay.
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Affiliation(s)
- S Lewallen
- Kilimanjaro Centre for Community Ophthalmology, PO Box 2254, Tumaini University/KCMC, Moshi, Tanzania.
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Hirneiss C, Klauss V, Wilke M, Kampik A, Taylor T, Lewallen S. [Ocular changes in tropical malaria with cerebral involvement--results from the Blantyre Malaria Project]. Klin Monbl Augenheilkd 2005; 222:704-8. [PMID: 16175479 DOI: 10.1055/s-2005-858445] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Malaria is a tropical disease causing an estimated 300 million infections and one million deaths per year. In sub-Saharan Africa, most infections are due to Plasmodium falciparum. The hallmark of the clinical syndrome of cerebral malaria is coma, and the associated mortality rate, even in appropriately treated patients, is 15 - 50 %. Funduscopy plays a major role for the ophthalmologist in the differential diagnosis because of the characteristic changes. METHODS To date more than 1000 children who satisfied the standard clinical case definition of cerebral malaria were admitted to the Blantyre Malaria Project (Malawi, Africa) for inpatient treatment and examined using indirect ophthalmoscopy through fully dilated pupils. The gender distribution was homogeneous and the children were between 2 and 14 years old. The optic nerve head, central and peripheral retina and central and peripheral vessels were described and photographed using a hand-held fundus camera (KOWA). RESULTS The spectrum and severity of findings of the ocular fundus in children with CM include the following distinct entities: haemorrhages (with and without a white centre), cotton wool spots, papilloedema, retinal whitening and retinal vessel abnormalities that may appear to be orange or white. Most of the retinal haemorrhages (in 40 %) have white centres and resemble Roth spots. Cotton wool spots were seen in only 5 %. Papilloedema was also not commonly seen (8 %) but is a poor prognostic sign. Retinal whitening (in 50 %) is seen more commonly at the posterior pole than in the periphery. 20 % of patients show retinal vessel abnormalities that may be orange or white in colour. CONCLUSION Ocular fundus changes in CM can be detected by the ophthalmologist using simple means and are decisive for the prognosis and timely therapy for this potentially lethal disease.
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Affiliation(s)
- C Hirneiss
- Augenklinik der Ludwig-Maximilians-Universität, München.
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Geneau R, Lewallen S, Bronsard A, Paul I, Courtright P. The social and family dynamics behind the uptake of cataract surgery: findings from Kilimanjaro region, Tanzania. Br J Ophthalmol 2005; 89:1399-402. [PMID: 16234438 PMCID: PMC1772921 DOI: 10.1136/bjo.2005.075572] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIMS To describe and understand better the barriers that elderly cataract patients in Kilimanjaro region (Tanzania) experience at the family level in order to access surgery. METHODS A phenomenological study carried out in the catchment area of a teaching hospital in Kilimanjaro Region. 60 semi-structured interviews were conducted with patients and ex-cataract patients. RESULTS The perceived need for sight and for surgery appears partly socially constructed at the family level. It was found that women were less likely to express a need for sight for fear of being seen as a burden. Furthermore, young heads of family are more inclined to support old men than old women. The consensus is that asking children for help can be difficult. Going for cataract surgery must be seen as a social process where elderly patients might have to wait or negotiate support for weeks, months, or even years. CONCLUSIONS Eye programmes must promote the benefits of cataract surgery to all family members, not just to the patient. A changing social climate, changing expectations of vision, and evolving cost sharing systems will have significant, sometimes contradictory, impacts on use of eye care services. Strategies for reaching those without access to financial resources need to be strengthened.
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Affiliation(s)
- R Geneau
- Kilimanjaro Centre for Community Ophthalmology, Tumaini University/KCMC, PO Box 2254 Moshi, Tanzania.
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Lewallen S, Roberts H, Hall A, Onyange R, Temba M, Banzi J, Courtright P. Increasing cataract surgery to meet Vision 2020 targets; experience from two rural programmes in east Africa. Br J Ophthalmol 2005; 89:1237-40. [PMID: 16170107 PMCID: PMC1772904 DOI: 10.1136/bjo.2005.068791] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND The numbers of cataract surgeries done in sub-Saharan Africa fall short of Vision 2020 targets. Over a few years, two programmes in rural east Africa both achieved significant increases in the number of cataract surgeries they provide, resulting in cataract surgical rates of 1583 for Kwale District in Kenya and 1165 for Kilimanjaro Region in Tanzania. Key components of success in these two programmes are described. METHODS Data were collected on standard indicators and key personnel interviewed to describe the results and compare the methods employed to increase cataract surgical rates by the Kwale District Eye Centre programme and the Kilimanjaro regional Vision 2020 programme. RESULTS Key components of success shared by the programmes included: (1) programmes in the community and at the hospital are closely linked so that they increase capacity together; (2) community programmes are "patient friendly," providing service in one stop; (3) the examination team includes eye workers with enough skill to provide treatment and decide who is operable so that patients are not transported needlessly or sent through a lengthy referral chain; (4) sites for visits in the community are selected according to population distribution and they are visited according to a regular schedule. CONCLUSION The development of "bridging strategies" that create a strong link between hospitals providing clinical service and communities needing these services is a key component to realising Vision 2020 goals in sub-Saharan Africa.
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Affiliation(s)
- S Lewallen
- Kilimanjaro Centre for Community Ophthalmology, Tumaini University/KCM College, PO Box 2254, Moshi, Tanzania.
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Beare NA, Southern C, Lochhead J, Molyneux ME, Lewallen S, Harding SP. Inter-observer concordance in grading retinopathy in cerebral malaria. Ann Trop Med Parasitol 2002; 96:105-8. [PMID: 11989526 DOI: 10.1179/000349802125000565] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- N A Beare
- St Paul's Eye Unit, Royal Liverpool University Hospital, UK.
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White VA, Lewallen S, Beare N, Kayira K, Carr RA, Taylor TE. Correlation of retinal haemorrhages with brain haemorrhages in children dying of cerebral malaria in Malawi. Trans R Soc Trop Med Hyg 2001; 95:618-21. [PMID: 11816433 DOI: 10.1016/s0035-9203(01)90097-5] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Retinal haemorrhages increase in number with severity of Plasmodium falciparum malaria and occur in 35-40% of children with cerebral malaria. We performed clinical retinal examinations and histopathological examinations of retina, and parietal and cerebellar sections of the brains, in 33 children in Malawi who died with cerebral malaria, severe malaria anaemia, or coma of other causes. Haemorrhages were counted in a standardized fashion: the Spearman correlation coefficient between the number of haemorrhages in retina and brain was 0.741 for parietal tissue and 0.703 for cerebellar (P < 0.01 for both). Severity of haemorrhage in the retina correlates well with that in the brain. Retinal examination in cerebral malaria is a useful tool in predicting some of the pathophysiological processes occurring in the brain.
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Affiliation(s)
- V A White
- Departments of Pathology and Ophthalmology, Vancouver General Hospital, University of British Columbia, Vancouver, Canada
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Courtright P, Kim SH, Tungpakorn N, Cho BH, Lim YK, Lee HJ, Lewallen S. Lagophthalmos surgery in leprosy: findings from a population-based survey in Korea. LEPROSY REV 2001; 72:285-91. [PMID: 11715274 DOI: 10.5935/0305-7518.20010035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Lagophthalmos continues to be a serious problem in cured leprosy patients. We conducted a population-based survey of lagophthalmos surgical coverage (LSC), barriers to lagophthalmos surgery and outcome of lagophthalmos surgery in leprosy patients in South Korea. In our survey, there were 60 patients with lagophthalmos who had needed surgery (> 5 mm gap), 34 of whom had received surgery, resulting in a lagophthalmos surgery coverage of 57%. Among the 34 patients who had received lagophthalmos surgery, 18 needed further surgery. Among those who had never had surgery, none of the demographic indicators predicted surgical uptake; the primary reason given for failure to have surgery was lack of knowledge about it. Outcome of surgery (by eye) showed that 29% of eyes still had a gap of 5 mm or more. The frequency of symptoms (tearing, blurring of vision, pain, etc.) was high. Even in settings with a good eye care infrastructure, such as Korea, uptake of surgery can still be low and results may not be satisfactory to patients. There is a need for practical guidelines for leprosy control programmes in the areas of (a) patient recognition, (b) patient education, (c) monitoring the uptake of surgery, and (d) monitoring the outcome of surgery to ensure the best possible outcome.
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Affiliation(s)
- P Courtright
- British Columbia Centre for Epidemiologic & International Ophthalmology, University of British Columbia, St. Paul's Hospital, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada.
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Abstract
AIM To review the prevalence and causes of blindness in sub-Saharan Africa, the existing services and limitations, and the Vision 2020 goals for the future. METHODS Methodologically sound population based surveys published in the past 20 years are reviewed and results for prevalence and causes of blindness are tabulated. The current resources and needs according to recent publications and international working groups are described. CONCLUSIONS Blindness prevalence rates vary widely but the evidence suggests that approximately 1% of Africans are blind. The major cause is cataract; trachoma and glaucoma are also important causes of blindness. The bulk of blindness in the region is preventable or curable. Efforts should focus on eye problems which are universally present and for which there are cost effective remedies, such as cataract and refractive problems and on those problems which occur focally and can be prevented by primary healthcare measures, such as trachoma, onchocerciasis, and vitamin A deficiency. Major development of staffing levels, infrastructure, and community programmes will be necessary to achieve Vision 2020 goals.
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Affiliation(s)
- S Lewallen
- British Columbia Centre for Epidemiologic and International Ophthalmology
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Courtright P, Lewallen S, Tungpakorn N, Cho BH, Lim YK, Lee HJ, Kim SH. Cataract in leprosy patients: cataract surgical coverage, barriers to acceptance of surgery, and outcome of surgery in a population based survey in Korea. Br J Ophthalmol 2001; 85:643-7. [PMID: 11371479 PMCID: PMC1723998 DOI: 10.1136/bjo.85.6.643] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND/AIMS Cataract is the leading cause of blindness in leprosy patients. There is no population based information on the cataract surgical coverage, barriers to use of surgical services, and outcome of surgery in these patients. We sought to determine these measures of cataract programme effectiveness in a cured leprosy population in South Korea. METHODS The population consisted of residents of six leprosy resettlement villages in central South Korea. All residents were invited to participate in a study of eye disease and interviewed regarding use of surgical services and reasons for not using these services. RESULTS The cataract surgical coverage in this population was 55.4% when <6/18 was used as the cut off and increased to 78.3% when the cut off was <6/60. Barriers reported by patients included being told by the doctor that the cataract was not mature and a perception by the patient that there was no need for surgery. Among patients who had aphakic surgery, 71% were still blind in the operative eye while among patients who had pseudophakic surgery, 14% were still blind (presenting vision). Blindness in pseudophakic patients could be reduced to 3% with spectacle correction. CONCLUSION Cataract prevalence in leprosy patients will increase as life expectancy continues to increase. Leprosy control programmes will need to develop activities aimed at reducing the burden of cataract. Recommendations include establishing collaborative agreements with ophthalmological services to provide high quality IOL surgery to these patients, training of health staff to identify and refer patients in need of surgery, monitoring the uptake of cataract surgery among patients needing services, and monitoring the outcome of surgery to improve refractive outcome.
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Affiliation(s)
- P Courtright
- British Columbia Centre for Epidemiologic and International Ophthalmology, University of British Columbia, Vancouver, BC, Canada.
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Abstract
BACKGROUND Many individual surveys of blindness have reported slightly higher rates of blindness for women. In order to gain a continent-by-continent and global sense of the burden of blindness by sex we conducted a meta-analysis of published, population-based surveys of blindness. METHOD Published reports were collected using a predetermined search protocol involving commercial electronic databases, hand-searching of references and direct contact with researchers. Studies were included that were population-based, included clinical examination and had a minimum sample size of 1000. The studies were critically appraised to determine methodological rigour. Data were analysed using the Cochrane Collaboration Review Manager. RESULTS The overall odds ratio (age-adjusted) of blind women to men is 1.43 (95% CI 1.33-1.53), ranging from 1.39 (95% CI 1.20-1.61) in Africa, 1.41 (95% CI 1.29-1.54) in Asia, and 1.63 (95% CI 1.30-2.05) in industrialised countries. There was good homogeneity of findings from Africa, Asia, and the industrialised countries. Globally, women bear excess blindness compared to men. In these surveys, overall, women account for 64.5% of all blind people. The excess of blindness in women was marked among the elderly and not due only to differential life expectancy. CONCLUSION The excess burden of blindness among women is likely due to a number of factors, which are different in industrialised countries compared to developing countries. Particular attention to gender differences in blindness is needed in the creation of targets for blindness reduction and in the development of interventions.
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Affiliation(s)
- I Abou-Gareeb
- British Columbia Centre for Epidemiologic & International Ophthalmology, University of British Columbia, Vancouver, British Columbia, Canada
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Lewallen S, Tungpakorn NC, Kim SH, Courtright P. Progression of eye disease in "cured" leprosy patients: implications for understanding the pathophysiology of ocular disease and for addressing eyecare needs. Br J Ophthalmol 2000; 84:817-21. [PMID: 10906083 PMCID: PMC1723588 DOI: 10.1136/bjo.84.8.817] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Ocular damage in leprosy is due either to nerve damage or infiltration by mycobacteria. There is currently little information about the magnitude and nature of incident ocular pathology in cured leprosy patients. This information would increase our understanding of the pathophysiology of ocular involvement in leprosy and help in developing programmes to address the eyecare needs of leprosy patients who have been released from treatment. The cumulative incidence of leprosy related ocular pathology and cataract was measured during an 11 year follow up period in cured leprosy patients released from treatment in Korea. METHODS In 1988 standardised eye examinations were performed on 501 patients in eight resettlement villages in central South Korea. In May 1999 standardised eye examinations were repeated in this population. RESULTS Among the patients in whom there was no sight threatening leprosy related ocular disease (lagophthalmos, posterior synechia, or keratitis) in 1988, 14.7% developed one or more of these conditions. Overall, among those with no vision reducing cataract in 1988, 26.4% had developed a vision reducing lens opacity in at least one eye. Among patients examined in both 1988 and 1999, 14.3% developed visual impairment and 5.7% developed blindness. CONCLUSION This study demonstrates that leprosy related ocular pathology progresses in some patients even after they are cured mycobiologically. The progressive leprosy related lesions are the result of chronic nerve damage; ocular lesions due to infiltration by Mycobacterium leprae did not develop. Based on the factors found to be associated with development of the most visually significant findings (posterior synechia, keratitis, and cataract) certain patients should be targeted at discharge for active follow up eye care. We suggest that patients with lagophthalmos (even in gentle closure), trichiasis, small pupils, and posterior synechiae should be screened regularly for the development of lagophthalmos in forced closure, keratitis, and cataract.
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Affiliation(s)
- S Lewallen
- British Columbia Centre for Epidemiologic and International Ophthalmology, University of British Columbia, Vancouver, Canada.
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Lewallen S, White VA, Whitten RO, Gardiner J, Hoar B, Lindley J, Lochhead J, McCormick A, Wade K, Tembo M, Mwenechanyana J, Molyneux ME, Taylor TE. Clinical-histopathological correlation of the abnormal retinal vessels in cerebral malaria. Arch Ophthalmol 2000; 118:924-8. [PMID: 10900105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
BACKGROUND Clinically abnormal retinal vessels unique to cerebral malaria have previously been shown to be associated with a poor outcome in African children. There have been no studies of the histopathological correlates of these vessels. DESIGN This is a descriptive study of the clinical-histopathological correlates of the retinal vessels of 11 children who died with cerebral malaria. RESULTS The retinal vessels in children with cerebral malaria contained many parasitized red blood cells; these cells tended to cluster at the periphery of vessels or, in the case of capillaries, to fill the vessel. Those with late-stage parasites had markedly reduced amounts of hemoglobin. The pattern of dehemoglobinization corresponds to the pattern of clinically abnormal vessels. CONCLUSIONS The sequestration of late-stage parasitized red blood cells with reduced amounts of hemoglobin accounts for the unique white and pale orange retinal vessels seen in cerebral malaria. Clinical examination of these "marked" vessels offers a method to monitor a basic pathophysiological process of cerebral malaria in vivo. Arch Ophthalmol. 2000;118:924-928
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Affiliation(s)
- S Lewallen
- British Columbia Centre for Epidemiologic and International Ophthalmology, University of British Columbia, 1081 Burrad St, Vancouver, British Columbia, Canada V6Z 1Y6.
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Lewallen S, Courtright P. Recognising and reducing barriers to cataract surgery. Community Eye Health 2000; 13:20-1. [PMID: 17491950 PMCID: PMC1705969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Affiliation(s)
- S Lewallen
- British Columbia Centre for, Epidemiologic & International, Ophthalmology, St Paul's Hospital, Vancouver, BC, Canada
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Lewallen S, Harding SP, Ajewole J, Schulenburg WE, Molyneux ME, Marsh K, Usen S, White NJ, Taylor TE. A review of the spectrum of clinical ocular fundus findings in P. falciparum malaria in African children with a proposed classification and grading system. Trans R Soc Trop Med Hyg 1999; 93:619-22. [PMID: 10717749 DOI: 10.1016/s0035-9203(99)90071-8] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ocular fundus pathology in Plasmodium falciparum malaria is common and has prognostic significance. We have made a collaborative effort to document the ocular features in several populations. Based on examination of 735 patients in Malawi, Kenya and The Gambia by direct and indirect ophthalmoscopy with dilated pupils, we have determined that the 5 distinct clinical features (in order of frequency) include retinal whitening, haemorrhages, unique vessel abnormalities, papilloedema, and cotton wool spots. Photographs and descriptions of these are presented, along with a proposed grading scheme.
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Affiliation(s)
- S Lewallen
- British Columbia Centre for Epidemiologic and International Ophthalmology, Department of Ophthalmology, St Paul's Hospital, University of British Columbia, Vancouver, Canada.
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van Dijk K, Lewallen S, Chirambo M, Gardiner J, Hoar B, Lindley J, Wade NK, Courtright P. Creation and testing of a practical visual function assessment for use in Africa: correlation with visual acuity, contrast sensitivity, and near vision in Malawian adults. Br J Ophthalmol 1999; 83:792-5. [PMID: 10381665 PMCID: PMC1723105 DOI: 10.1136/bjo.83.7.792] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM To develop and test a practical visual function assessment for use in developing countries. METHODS Using focus group discussions and interviews with eyecare workers and low vision specialists in Malawi, 13 questions related to visual characteristics of activities of daily living were designed. Patients presenting to an eye clinic were recruited and interviewed. Visual acuity, near vision, and contrast sensitivity were measured. Analysis sought to determine the degree of correlation between the vision indices and visual function. RESULTS The visual function questionnaire was easy to administer. Visual function correlated with visual acuity, contrast sensitivity, near vision, and patient reported visual problem. People with a higher frequency of "not applicable" responses had lower visual function scores. Multivariate modelling revealed that visual acuity and number of questions felt to be applicable were independently associated with visual function. Reducing the questionnaire to nine questions did not affect the degree of correlation with any of the visual indices. CONCLUSION The authors' visual function assessment correlates well with different measures of visual acuity. People with reduced vision for a prolonged period may no longer consider doing certain tasks and the number of questions considered appropriate by an individual may be an additional measure of visual function. Assessment of visual function by health workers may be a valuable tool in improving surgical uptake by encouraging both health personnel and patients to recognise that they have difficulties undertaking activities of daily living as well as a measure of monitoring and evaluating cataract outcomes.
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Affiliation(s)
- K van Dijk
- Christoffel Blindenmission, Boshof 10, 7873 AC Odoorn, Netherlands
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Lewallen S, Courtright P. Software Review. Annals of Tropical Medicine & Parasitology 1999. [DOI: 10.1080/00034983.1999.11813428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Lewallen S. The fundus in severe malaria. Arch Ophthalmol 1998; 116:542-3. [PMID: 9565061 DOI: 10.1001/archopht.116.4.542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Lewallen S, Taylor TE, Molyneux ME, Semba RD, Wills BA, Courtright P. Association between measures of vitamin A and the ocular fundus findings in cerebral malaria. Arch Ophthalmol 1998; 116:293-6. [PMID: 9514481 DOI: 10.1001/archopht.116.3.293] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To investigate the relationship between serum vitamin A levels and conjunctival impression cytology and retinal whitening present in Malawian children with cerebral malaria. METHODS Standard retinal examination and conjunctival impression cytology were performed at hospital admission on 101 consecutively admitted children with cerebral malaria. Blood samples were drawn from 56 children at 24 hours, frozen at -20 degrees C, and transported for assessment of vitamin A levels by high-performance liquid chromatography. Associations among fundus findings and vitamin A measurements were sought. RESULTS The whitening of the retina that we have previously described in children with cerebral malaria was found to be associated with a mean+/-SD serum vitamin A level of 0.29+/-0.1 micromol/L, compared with a mean vitamin A level of 0.41+/-0.2 micromol/L in children without retinal whitening. Children with retinal whitening were 2.77 (95% CI, 1.06-7.3) times more likely to have abnormal conjunctival impression cytology results than those without whitening. No child had any clinical or ophthalmologic evidence of chronic vitamin A deficiency. CONCLUSIONS The retinal whitening described in children with cerebral malaria is associated with low serum vitamin A levels and with abnormal conjunctival impression cytology results and may be due to acute vitamin A deficiency at the tissue level.
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Affiliation(s)
- S Lewallen
- British Columbia Centre for Epidemiologic and International Ophthalmology, Vancouver, Canada
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Lewallen S, Courtright P. Epidemiology in practice: case-control studies. Community Eye Health 1998; 11:57-8. [PMID: 17492047 PMCID: PMC1706071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Affiliation(s)
- S Lewallen
- BC Centre for Epidemiologic & International Ophthalmology, University of British Columbia, St Paul's Hospital, Vancouver V6Z 1Y6, Canada
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Abstract
Vision loss and blindness are potential complications of leprosy. There is little data available to indicate the impact of eye complications on life expectancy and quality of life. We sought to determine the relative risk of death in blind leprosy patients compared to nonblind leprosy patients. A population-based ocular survey of 510 mycobacteriologically negative leprosy patients in rural South Korea, conducted in 1988, formed the study population. After a 7-year period patients were traced to determine their status (alive, dead, lost to follow up). Blind patients showed a 4.8-fold risk of death, even after adjusting for other factors, compared to nonblind patients. Young blind leprosy patients had the highest relative risk of death. Excess mortality was not associated with any specific cause of blindness, ocular pathology, or type of disease. Findings from our study suggest that all leprosy patients with ocular disabilities (including those released from antileprosy treatment) should be targeted to receive eye care to prevent vision loss. Particular emphasis should be placed on young patients.
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Affiliation(s)
- P Courtright
- British Columbia Centre for Epidemiologic & International Ophthalmology, St Paul's Hospital, Vancouver, Canada
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Abstract
An estimated 30 million people worldwide have been infected with the human immunodeficiency virus, the causative agent of the acquired immunodeficiency syndrome. Of these, 90% live in developing countries from where there is relatively little published information about the ocular manifestations of human immunodeficiency virus and acquired immunodeficiency syndrome. We review the information available from Africa, Latin America, and Asia. The prevailing ocular manifestations differ in some developing countries compared with those in the industrialized countries. These differences most likely result from different socioeconomic conditions and basic health care availability and from different patterns of endemic disease present before the human immunodeficiency virus epidemic.
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Affiliation(s)
- S Lewallen
- Department of Ophthalmology, University of British Columbia, St Paul's Hospital, Vancouver, Canada
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Lewallen S. Prevention of blindness in leprosy: an overview of the relevant clinical and programme-planning issues. Ann Trop Med Parasitol 1997; 91:341-8. [PMID: 9290840 DOI: 10.1080/00034989760950] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Visual disability continues to be a significant problem in leprosy patients due to cataract, chronic iridocyclitis, and corneal disease. Clinical and epidemiological aspects of these problems are described and the current status of eye care in leprosy programmes is discussed.
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Affiliation(s)
- S Lewallen
- B.C. Centre for Epidemiologic and International Ophthalmology, University of British Columbia, St Paul's Hospital, Vancouver, Canada.
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Lewallen S. Ocular manifestations of the human immunodeficiency virus and the acquired immunodeficiency syndrome in developing countries. Arch Ophthalmol 1997; 115:435. [PMID: 9076228 DOI: 10.1001/archopht.1997.01100150437033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Courtright P, Lewallen S, Kanjaloti S. Changing patterns of corneal disease and associated vision loss at a rural African hospital following a training programme for traditional healers. Br J Ophthalmol 1996; 80:694-7. [PMID: 8949711 PMCID: PMC505583 DOI: 10.1136/bjo.80.8.694] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
AIMS/BACKGROUND Use of African traditional eye medicines (TEM) is associated with the presence of corneal disease, delay in presentation, and vision loss. An interactive training programme was conducted with traditional healers in Chikwawa District, Malawi and changes in the pattern of corneal disease assessed in patients presenting to the district hospital after the training. METHODS All patients presenting to the district hospital with corneal disease for a 15 month period before intervention and a 12 month period after intervention were enrolled in the study. Interviews and examinations were carried out by the same person using a standardised, pretested form. RESULTS Among the 175 pre-intervention and 97 post-intervention patients, delay in presentation improved only slightly. Blindness among patients reporting the use of TEM decreased from 44% to 21%; bilateral corneal disease in patients using TEM decreased from 31% to 10%. Multivariate analysis demonstrates that poor vision in corneal disease patients continues to be associated with TEM use and distance from the district hospital. CONCLUSION As there were no other relevant eye health programmes in the district it is believed that this collaborative eye care programme with the traditional healers was likely to have been responsible for many of the changes in the pattern of corneal disease in the district. Although the changing patterns are encouraging and are likely to improve with additional collaboration, distance to a district hospital will continue to be a barrier to timely use of Western eye care services.
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Affiliation(s)
- P Courtright
- BC Centre for Epidemiologic and International Ophthalmology, University of British Columbia, Vancouver, Canada
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Abstract
AIM To investigate the association of human immunodeficiency virus (HIV) infection and carcinoma of the conjunctiva in Africa, and the role of human papilloma virus type 16 (HPV-16). METHODS Patients in Uganda and Malawi presenting to eye clinics with lesions suspicious of carcinoma were studied. Pathological confirmation of eye lesions was sought. HIV testing of patients who were biopsied and, in Uganda, of matched case control subjects was carried out as was testing of a sample of fixed biopsies for HPV-16 by polymerase chain reaction (PCR). The HIV-1 serology, histopathology of conjunctival biopsies (conjunctival intraepithelial neoplasia (CIN), invasive carcinoma, other lesions), and prevalence of HPV-16 infection were determined. RESULTS Of Ugandan patients, 27/38 (71%) with carcinoma (27 invasive carcinoma, 11, CIN) were HIV positive compared with 12/76 (16%) of controls (odds ratio 13, 95% confidence interval 5-38). The calculated population aetiological fraction of carcinoma associated with HIV was 66%. Of 32 Malawian patients (20 invasive carcinoma, 12 CIN), 25/29 tested (86%) were HIV positive. HPV-16 infection was found in 7/20 (35%) of carcinoma samples, 0/9 pingueculae, and 2/6 conjunctivitis samples. CONCLUSIONS HIV infection is strongly associated with an apparent increase in the incidence of conjunctival carcinoma in Africa. While ultraviolet light is probably the prime risk factor and HPV-16 is implicated in a proportion of cases, the interactions of ultraviolet light, HIV, HPVs, and other factors are unclear in the pathogenesis of carcinoma. The disease represents another model of multifactorial epithelial carcinogenesis.
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Abstract
The pathogenesis of cerebral malaria is poorly understood. Direct and indirect ophthalmoscope examinations of 141 Malawian children with strictly defined cerebral malaria revealed 2 distinct and prognostically significant findings: papilloedema and extramacular retinal oedema. The relative risk of death in patients with papilloedema was 6.7 times that in patients without papilloedema. Extramacular retinal oedema was associated with a 2.9 fold increase in the relative risk of dying. The mortality rate in patients with neither of these signs was only 1.3% compared to an overall mortality rate of 9.2%. The clinical and laboratory features associated with each of these ophthalmological findings were different, suggesting that there may be at least 2 different pathogenetic processes in patients with cerebral malaria.
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Affiliation(s)
- S Lewallen
- International Eye Foundation, Blantyre, Malawi
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Abstract
Polymerase chain reaction was used to test for the presence of human papillomavirus in conjunctival squamous cell carcinomas from three young Africans with aggressive disease. Two of these patients had the acquired immunodeficiency syndrome. Test results for human papillomavirus were negative [corrected] in all three cases.
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Affiliation(s)
- S Lewallen
- Department of Ophthalmology, Queen Elizabeth Central Hospital, Blantyre, Malawi
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Abstract
Refractive errors, particularly myopia, are a common problem in industrialized countries, but the impression exists that myopia may be relatively uncommon in non-industrialized societies. We conducted a population-based survey of refractive error in two groups of Malawians: a group of rural agricultural workers (n = 510) and a group of students at an urban teachers' college (n = 534). The overall prevalence of myopia was low; 2.5% (95% confidence interval 1.3%, 3.7%) of participants had an error of -0.5 D or greater. The mean refractive error (right eye) in the urban student group was +0.52 D compared to +0.62 D among the rural agricultural workers and the excess myopia was accounted for by significant myopia (> or = -0.75 D) in a few individuals, rather than an overall shift towards myopia within the urban student group. Among the rural agricultural workers, literacy predicted refractive error (right eye), with a mean of +0.59 D in the rural literate compared to +0.67 D in the rural illiterate. These findings support the notion that myopia is uncommon in non-industrialized societies and that it is associated with increased literacy but we have not identified specific risk factors within this group to predict the occurrence of significant myopia. In settings such as Malawi, refractive services should be targeted to urban centers, where more educated populations are likely to be found.
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Affiliation(s)
- S Lewallen
- International Eye Foundation, Blantyre, Malawi
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Abstract
PURPOSE During 5 days in January 1994, two visiting expatriate ophthalmologists performed extracapsular cataract surgery on 111 patients at a nonprofit hospital in Asia. The authors investigated the development of postoperative corneal edema. METHODS An epidemiologic and clinical investigation was undertaken by a review of clinical charts, interview of personnel involved, an examination and interview of patients who underwent surgery, and a laboratory simulation of the disinfection procedure used. RESULTS Follow-up was available on 58% of the patients. The attack rate was at least 37% and likely to be approximately 64%. The attack rate was highest the first 2 days of surgery. Multivariate analysis showed that the day of surgery was the only characteristic significantly associated with the presence of corneal edema. A simulation of the disinfection technique used (soaked in 2% glutaraldehyde and rinsing) showed that significant levels of glutaraldehyde remain in instruments with small lumens after the rinse. CONCLUSION The epidemiologic data and simulation information are compatible; the lack of adequate rinsing of small lumen instruments soaked in glutaraldehyde is the most probable cause of this incident. Recommendations for surgeons on surgical expeditions are proposed.
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Affiliation(s)
- P Courtright
- University of British Columbia, Department of Ophthalmology, Faculty of Medicine, Vancouver, Canada
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Courtright P, Lewallen S, Li HY, Hu LF, Yang JW. Lagophthalmos in a multibacillary population under multidrug therapy in the People's Republic of China. LEPROSY REV 1995; 66:214-9. [PMID: 7500816 DOI: 10.5935/0305-7518.19950023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Lagophthalmos may be the most common potentially blinding ocular condition in leprosy. The magnitude of the problem among multibacillary patients has not been determined. We sought to ascertain the magnitude of lagophthalmos in a multibacillary leprosy patient population under multidrug therapy (MDT) (both newly diagnosed and with a prior history of dapsone monotherapy) in China and assess factors associated with its presence. In a survey of 640 multibacillary patients 3.8% of the newly diagnosed patients and 10.2% of the patients with prior dapsone monotherapy had lagophthalmos. Corneal disease and vision loss were common in both groups. Poor compliance with MDT, duration between onset and diagnosis, and duration on dapsone monotherapy were associated with the presence of lagophthalmos. Our findings suggest that there may be a threshold at which MDT must be maintained to prevent lagophthalmos. Early leprosy diagnosis and treatment would also lessen the incidence of lagophthalmos in these patients. The high proportion of lagophthalmos patients with corneal disease suggests that there has been inadequate eye care for these patients.
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Affiliation(s)
- P Courtright
- Department of Ophthalmology, University of British Columbia, St Paul's Hospital, Vancouver, Canada
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Abstract
Existing data suggest that, at a minimum, 2% of paucibacillary patients and 5% of multibacillary patients have lagophthalmos; at least 290,000 people worldwide have leprosy-related lagophthalmos. Surgical intervention is the only method for correcting lagophthalmos; effectiveness of the different procedures commonly used has not been measured. Results from a survey of eye care providers revealed that surgeons in Asia used a wide range of different techniques for the correction of lagophthalmos while almost all of the surgeons in Africa used tarsorrhaphy. There is a need to evaluate surgical outcome of these techniques and to develop guidelines to assist in increasing the number of surgeries for lagophthalmos in leprosy patients.
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Affiliation(s)
- P Courtright
- Department of Ophthalmology, University of British Columbia, St Paul's Hospital, Vancouver, Canada
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Abstract
The most common cause of monocular blindness in Africa is corneal opacification. Traditional eye medicines (TEM) are widely used in Africa and their use has been associated with corneal ulceration, however, no controlled studies of the effects of TEM on the cornea have been published. We conducted a case-control study of 39 patients with corneal ulcers matched to controls with severe conjunctivitis. Microbiological investigations were conducted on 20 cases. There was a significant association between corneal ulceration and TEM use and, in particular, peripheral corneal ulcerations were significantly associated with TEM use.
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Affiliation(s)
- S Lewallen
- International Eye Foundation, Blantyre, Malawi
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Abstract
Over a 15 month period all patients with corneal ulcers presenting at two district hospitals were interviewed regarding demographic and clinical characteristics and their use of traditional eye medicines (TEM). Of the 583 patients interviewed, 33.8% reported using TEM. There were no age or sex differences in TEM use. Patients who reported TEM use took, on average, 51 days between onset of symptoms and presentation while patients who denied TEM use took 13 days. Sixteen per cent of TEM users had a vision in the affected eye of < 3/60 on presentation compared with 5% of non-TEM users. The frequent use of TEM and the presence of numerous traditional healers in rural areas of Africa suggest that eye care programmes could benefit greatly by including traditional healers in primary eye care activities.
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Abstract
OBJECTIVE The objective was to describe the complications and outcomes of herpes zoster ophthalmicus in a population of young Africans with a high seroprevalence of human immunodeficiency virus type 1 in which treatment often is delayed and in which antiviral drugs are not available. METHODS Twenty-seven patients with herpes zoster ophthalmicus presenting consecutively to a large urban hospital were examined and followed. Treatment was limited to that which was locally available. RESULTS Visual outcomes were poor. Sixty-six percent of eyes had final visual acuity less than 20/60. Forty percent had light perception or no light perception visual acuity. Severe keratouveitis and corneal perforation were common and responsible for most poor visual outcomes. CONCLUSION Young Africans with herpes zoster ophthalmicus are at a high risk for significant visual loss.
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Affiliation(s)
- S Lewallen
- International Eye Foundation, Blantyre, Malawi, Africa
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