The Global Retinoblastoma Outcome Study: a prospective, cluster-based analysis of 4064 patients from 149 countries

Background

Retinoblastoma is the most common intraocular cancer worldwide. There is some evidence to suggest that major differences exist in treatment outcomes for children with retinoblastoma from different regions, but these differences have not been assessed on a global scale. We aimed to report 3-year outcomes for children with retinoblastoma globally and to investigate factors associated with survival.

Methods

We did a prospective cluster-based analysis of treatment-naive patients with retinoblastoma who were diagnosed between Jan 1, 2017, and Dec 31, 2017, then treated and followed up for 3 years. Patients were recruited from 260 specialised treatment centres worldwide. Data were obtained from participating centres on primary and additional treatments, duration of follow-up, metastasis, eye globe salvage, and survival outcome. We analysed time to death and time to enucleation with Cox regression models.

Findings

The cohort included 4064 children from 149 countries. The median age at diagnosis was 23·2 months (IQR 11·0–36·5). Extraocular tumour spread (cT4 of the cTNMH classification) at diagnosis was reported in five (0·8%) of 636 children from high-income countries, 55 (5·4%) of 1027 children from upper-middle-income countries, 342 (19·7%) of 1738 children from lower-middle-income countries, and 196 (42·9%) of 457 children from low-income countries. Enucleation surgery was available for all children and intravenous chemotherapy was available for 4014 (98·8%) of 4064 children. The 3-year survival rate was 99·5% (95% CI 98·8–100·0) for children from high-income countries, 91·2% (89·5–93·0) for children from upper-middle-income countries, 80·3% (78·3–82·3) for children from lower-middle-income countries, and 57·3% (52·1-63·0) for children from low-income countries. On analysis, independent factors for worse survival were residence in low-income countries compared to high-income countries (hazard ratio 16·67; 95% CI 4·76–50·00), cT4 advanced tumour compared to cT1 (8·98; 4·44–18·18), and older age at diagnosis in children up to 3 years (1·38 per year; 1·23–1·56). For children aged 3–7 years, the mortality risk decreased slightly (p=0·0104 for the change in slope).

Interpretation

This study, estimated to include approximately half of all new retinoblastoma cases worldwide in 2017, shows profound inequity in survival of children depending on the national income level of their country of residence. In high-income countries, death from retinoblastoma is rare, whereas in low-income countries estimated 3-year survival is just over 50%. Although essential treatments are available in nearly all countries, early diagnosis and treatment in low-income countries are key to improving survival outcomes.

Funding

Queen Elizabeth Diamond Jubilee Trust.

Profile of primary childhood glaucoma at a child eye health tertiary facility in Malawi

BACKGROUND

To describe the clinical characteristics and treatment of primary childhood glaucoma at Queen Elizabeth Central Hospital in Blantyre, Malawi.

METHODS

A retrospective case notes review was undertaken of all medical records of patients aged less than 16 years with a diagnosis of primary glaucoma according to the Childhood Glaucoma Research Network Classification (CGRN) who presented from January 2016 to December 2018. The parameters extracted from the case files included age at presentation, sex, type of glaucoma, presenting complaints, laterality of ocular involvement, examination findings and the treatment modality instituted. The Mann-Whitney test was used to investigate factors associated with the intraocular pressure (IOP) in eyes that had a higher presenting IOP value compared to contralateral eyes.

RESULTS

A total of 45 subjects (80 eyes) were identified, 42 with primary congenital glaucoma (PCG) and 3 with juvenile open angle glaucoma (JOAG). The mean age for the population was 2.6 years (S.D ± 3.7) and most of the patients were male, with a male-female ratio of 2:1. The majority of patients had bilateral disease (n = 35, 77.8%) with the commonest presenting complaint being a whitish appearance of the eye (57.5%). The eyes studied had a mean IOP of 30.1 mmHg (CI 27.4-32.9), a mean horizontal corneal diameter (HCD) of 13.6 mm (CI 13.1-14.2) and a mean cup-disc-ratio `(CDR) of 0.73 (CI 0.66-0.79). In addition, 62 eyes (77.5%) had corneal haze on examination. Most patients (n = 59, 73.8%) underwent a combined trabeculotomy - trabeculectomy surgery within the study period. The median presenting IOP was significantly higher with JOAG compared to PCG (P = 0.02).

CONCLUSION

PCG was the most common primary childhood glaucoma at Queen Elizabeth Central Hospital and most patients presented with bilateral eye involvement. Most of the eyes had corneal haze and JOAG was associated with a higher presenting IOP compared to PCG. Further studies to investigate the outcomes of combined trabeculotomy - trabeculectomy surgery in primary childhood glaucoma in Malawi are recommended.

Travel burden and clinical presentation of retinoblastoma: analysis of 1024 patients from 43 African countries and 518 patients from 40 European countries

BACKGROUND

The travel distance from home to a treatment centre, which may impact the stage at diagnosis, has not been investigated for retinoblastoma, the most common childhood eye cancer. We aimed to investigate the travel burden and its impact on clinical presentation in a large sample of patients with retinoblastoma from Africa and Europe.

METHODS

A cross-sectional analysis including 518 treatment-naïve patients with retinoblastoma residing in 40 European countries and 1024 treatment-naïve patients with retinoblastoma residing in 43 African countries.

RESULTS

Capture rate was 42.2% of expected patients from Africa and 108.8% from Europe. African patients were older (95% CI -12.4 to -5.4, p<0.001), had fewer cases of familial retinoblastoma (95% CI 2.0 to 5.3, p<0.001) and presented with more advanced disease (95% CI 6.0 to 9.8, p<0.001); 43.4% and 15.4% of Africans had extraocular retinoblastoma and distant metastasis at the time of diagnosis, respectively, compared to 2.9% and 1.0% of the Europeans. To reach a retinoblastoma centre, European patients travelled 421.8 km compared to Africans who travelled 185.7 km (p<0.001). On regression analysis, lower-national income level, African residence and older age (p<0.001), but not travel distance (p=0.19), were risk factors for advanced disease.

CONCLUSIONS

Fewer than half the expected number of patients with retinoblastoma presented to African referral centres in 2017, suggesting poor awareness or other barriers to access. Despite the relatively shorter distance travelled by African patients, they presented with later-stage disease. Health education about retinoblastoma is needed for carers and health workers in Africa in order to increase capture rate and promote early referral.

Global Retinoblastoma Presentation and Analysis by National Income Level

Importance

Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale.

Objectives

To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis.

Design, Setting, and Participants

A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017.

Main Outcomes and Measures

Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis.

Results

The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (n = 3685 [84.7%]) were from low- and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 [62.8%]), followed by strabismus (n = 429 [10.2%]) and proptosis (n = 309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]).

Conclusions and Relevance

This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs.

Establishing a Pediatric Ophthalmology Service in Malawi: Developments in Childhood Cataract Surgery

PURPOSE:

The purpose of this study is to report on the establishment of a Pediatric Ophthalmology Service for Malawi using childhood cataract surgery as a surrogate measure of its effectiveness.

MATERIALS AND METHODS:

A retrospective review of pediatric cataract surgery at Lions Sight First Eye Hospital, Blantyre, between 2011 and 2016. The paucity of comprehensive records allowed for the sampling of a maximum of 25 cases/year (n = 150) for comparison. Theatre records and population statistics were used to calculate childhood cataract surgical rates (CCSR).

RESULTS:

A total of 949 cataract operations were performed during the six years studied – 55.8% of these were boys. The number of operations per year remained generally stable. Of the 150 cases reviewed, the mean age at presentation was 6.01 years, with a trend toward a slightly younger age over the period. Over the years studied, the geographical distribution of referrals became more reflective of the population's distribution. Where the logarithm of the minimum angle of resolution (LogMAR) visions were available, these demonstrated a mean improvement from 2.008 (n = 43) preoperatively to 0.613 (n = 51) postoperatively. The mean follow-up was 106 days (0 days–3.25 years). Complication rates were low. The CCSR was 9.2/million population.

CONCLUSIONS:

A Pediatric Ophthalmology Service has been established in Malawi delivering safe, effective surgery on a country-wide scale for childhood cataract. Over the period studied, the age at presentation reduced, and there was an improvement in the geographical distribution of patients, likely due to an improvement in referral systems throughout Malawi.

Incremental cost-effectiveness of screening and laser treatment for diabetic retinopathy and macular edema in Malawi

Objective

To investigate the economic impact of introducing targeted screening and laser photocoagulation treatment for sight-threatening diabetic retinopathy and macular edema in a setting with no previous screening or laser treatment for diabetic retinopathy in sub-Saharan Africa.

Materials and methods

A cohort Markov model was built to compare combined targeted screening and laser treatment for patients with sight-threatening diabetic retinopathy and macular edema against no intervention. Primary outcomes were incremental cost per quality-adjusted life year (QALY) gained and per disability-adjusted life year (DALY) averted. Primary data were collected on 357 participants from the Malawi Diabetic Retinopathy Study, a prospective, observational cohort study. Multiple scenarios were explored and a probabilistic sensitivity analysis was performed.

Results

In the base case (age: 50 years, service utilization rate: 80%), the cost of the intervention and the years of severe visual impairment averted per patient screened were $209 and 2.2 years respectively. Applying the World Health Organization threshold of cost-effectiveness for Malawi ($679), the base case was cost-effective when QALYs were used ($400 per QALY gained) but not when DALYs were used ($766 per DALY averted). The intervention was more cost-effective when it targeted younger patients (age: 30 years) and less cost-effective when the utilization rate was lowered to 50%.

Conclusions

Annual photographic screening of diabetic patients attending medical diabetes clinics in Malawi, with the provision of laser treatment for those with sight-threatening diabetic retinopathy and macular edema, appears to be cost-effective in terms of QALYs gained, in our base case scenario. Cost-effectiveness improves if services are utilized more intensively and extended to younger patients.

First Prospective Cohort Study of Diabetic Retinopathy from Sub-Saharan Africa: High Incidence and Progression of Retinopathy and Relationship to Human Immunodeficiency Virus Infection

PURPOSE

To describe the prevalence, incidence, and progression of retinopathy and to report associations with demographic, clinical, and biochemical variables in people with diabetes in Southern Malawi.

DESIGN

Prospective cohort study.

PARTICIPANTS

Subjects were systematically sampled from 2 primary care diabetes clinics.

METHODS

We performed the first prospective cohort study of diabetic retinopathy from Sub-Saharan Africa over 24 months. Visual acuity, glycemic control, blood pressure, human immunodeficiency virus (HIV) status, urine albumin-to-creatinine ratio, hemoglobin, and lipids were assessed. Retinopathy was graded at an accredited reading center using modified Wisconsin grading of 4-field mydriatic photographs.

MAIN OUTCOME MEASURES

Incidence of sight-threatening retinopathy and progression of retinopathy by 2 steps on the Liverpool Diabetic Eye Study Scale.

RESULTS

A total of 357 subjects were recruited to the 24-month cohort study. At baseline, 13.4% of subjects were HIV positive and 15.1% were anemic. The 2-year incidence of sight-threatening diabetic retinopathy (STDR) for subjects with level 10 (no retinopathy), level 20 (background), and level 30 (preproliferative) retinopathy at baseline was 2.7% (95% confidence interval [CI], 0.1-5.3), 27.3% (95% CI, 16.4-38.2), and 25.0% (95% CI, 0-67.4), respectively. In a multivariate logistic analysis, 2-step progression of diabetic retinopathy was associated with glycosylated hemoglobin (odds ratio [OR], 1.27; 95% CI, 1.12-1.45), baseline grade of retinopathy (OR, 1.39; 95% CI, 1.02-1.91), and HIV infection (OR, 0.16; 95% CI, 0.03-0.78). At 2 years, 17 subjects (5.8%) lost ≥15 letters.

CONCLUSIONS

Incidence of STDR was approximately 3 times that reported in recent European studies. The negative association of HIV infection with retinopathy progression is a new finding.

A cost analysis of pediatric cataract surgery at two child eye health tertiary facilities in Africa

PURPOSE

To determine the direct cost of pediatric cataract surgery at two child eye health tertiary facilities (CEHTFs) in Africa.

METHODS

The direct cost of pediatric cataract surgery was determined by reviewing data collected from two CEHTFs in Zambia and Malawi. Inventory, cost, and usage data of all durable medical equipment, consumable equipment, personnel, and medications were collected and the direct cost per child calculated.

RESULTS

For cataract surgery and related treatment during 2011, the total cost per child was calculated to be $202 for Malawi and $277 for Zambia using figures derived from estimating labor cost allocation proportional to employee time devoted to pediatric cataract management. The one-time equipment cost totaled $178,121 for Malawi and $179,832 for Zambia.

CONCLUSIONS

These cost estimates may serve as a basis for economic decisions aimed at improving access to care, management, and follow-up for children with cataract and provide useful insights for programs dedicated to promoting organizational and financial sustainability for CEHTFs in Africa.

High prevalence in Malawi of sight-threatening retinopathy and visual impairment caused by diabetes: identification of population-specific targets for intervention

AIMS

To report the prevalence of all grades of diabetic retinopathy and associations with demographic, clinical and biochemical variables in people with diabetes in Southern Malawi.

METHODS

We report baseline data from a 24-month prospective cohort study. Subjects were systematically sampled from two hospital-based, primary care diabetes clinics. Visual acuity, glycaemic control, systolic blood pressure, HIV status, urine albumin-creatinine ratio, and haemoglobin and serum lipid levels were assessed. Retinopathy was graded at an accredited reading centre using modified Wisconsin grading of four-field mydriatic photographs.

RESULTS

A total of 357 subjects were studied. Of these, 13.4% subjects were HIV-positive and 15.1% had anaemia. The overall prevalence rates of any retinopathy, sight-threatening diabetic retinopathy and proliferative retinopathy were 50.1% (95% CI 44.9-55.3), 29.4% (95% CI 24.7-34.1) and 7.3% (95% CI 4.6-10.0), respectively. In multivariate logistic analysis the presence of sight-threatening retinopathy was associated with duration of diabetes (odds ratio 1.11, 95% CI 1.05-1.17), HbA1c (odds ratio 1.31, 95% CI 1.13-1.50), systolic blood pressure (odds ratio 1.03, 95% CI 1.01-1.04), haemoglobin (odds ratio 0.98, 95% CI 0.96-0.99) and LDL cholesterol (odds ratio 1.63, 95% CI 1.18-2.25). No significant association with HIV status was observed. In all, 3.6 and 1.4% of people in our study cohort had visual acuity worse than 6/18 and 6/60 in the better eye, respectively.

CONCLUSIONS

The present study found a prevalence of sight-threatening retinopathy in diabetes clinics in one Sub-Saharan African country of approximately four times that reported in recent European studies and a prevalence of proliferative retinopathy approximately 10 times higher. The association of sight-threatening retinopathy with lower haemoglobin level is a new finding. Our results highlight the urgent need for provision of services for retinopathy detection and management to avoid a large burden of vision loss.

Maternal and neonatal risk factors associated with vertical transmission of ophthalmia neonatorum in neonates receiving health care in Blantyre, Malawi

Context:

Neonatal conjunctivitis is associated with poor prenatal care worldwide.

Purpose:

Data on neonatal conjunctivitis is scarce in Malawi. This study describes risk factors associated with conjunctivitis in neonates born in a large tertiary care hospital in Blantyre, Malawi.

Materials and Methods:

Medical records of a retrospective cohort of 231 neonates diagnosed with conjunctivitis from January 2006 to December 2009 at a large tertiary hospital in Malawi were reviewed. All subjects were clinically diagnosed with ophthalmia neonatorum. Data were collected on patient demographics and clinical features. The frequencies were calculated of various risk factors in neonates with ophthalmia neonatorum and their mothers as well as the treatments administered.

Results:

Mean age of the mother was 23.45 years (range, 15-40 years), and the mean number of previous deliveries was 2.3 (range, 1-7) children. Nearly, 80% of mothers delivered preterm infants via spontaneous vaginal delivery. The mean birth weight of neonates was 2869.6 grams (1100-5000 grams). Among mothers, premature rupture of membranes was the leading risk factor (24%) followed by sepsis during labor (9%), and history of sexually transmitted infections (STI) (7%). Neonates presented with low Apgar scores (19%), fever (8%), and/or meconium aspiration (5%). Providers treated patients empirically with a varied combination of benzyl penicillin, gentamicin, tetracycline eye ointment, and saline eye wash. Tetracycline with a saline eyewash was used frequently (34%) compared with combinations of benzyl penicillin and gentamicin.

Conclusions:

Improving prenatal care to reduce sepsis, traumatic deliveries, and early diagnosis of STI with appropriate treatment may potentially reduce vertical transmission of neonatal conjunctivitis in this understudied population.

Presentation of Primary Open Angle Glaucoma (POAG) at Lions Sight First Eye Hospital in Blantyre, Malawi

OBJECTIVE

Primary open angle glaucoma (POAG) is the most common type of glaucoma in Africa. We carried out a study to determine the clinical presentation pattern of patients with primary open angle glaucoma (POAG) at a tertiary hospital in Malawi.

DESIGN

A cross-sectional study.

SETTING

Lions Sight First Eye Hospital-a major referral and teaching state eye hospital in Blantyre, Malawi.

SUBJECTS

Study participants were newly diagnosed POAG patients at specialist eye clinic during study period.

RESULTS

A total of 60 POAG patients were recruited into the study. The mean age was 58.7 years (SD= 16.6, range 18 - 86). There were more male (44, 73.3%) than female (16, 27.7%) patients. The majority of patients (73%) presented one year after onset of visual symptoms. Twenty-six patients (43%) had unilateral blindness (visual acuity < 3/60; WHO classification), while nine patients (15%) presented with bilateral blindness. A vertical cup-to-disc ratio (CDR) of 0.8 or worse was seen in 92 eyes (79%). The mean intraocular pressure (IOP) reading was 35.5 mmHg (SD 13.30). Of the thirty-three eyes that successfully underwent visual field analysis, very advanced defects were recorded in 12 eyes (36%).

CONCLUSION

This study demonstrates delayed presentation and male predominance among POAG patients at a tertiary eye hospital in Malawi. Glaucoma intervention programmes should aim at identifying patients with treatable glaucoma with particular attention to women.

Diabetic retinopathy in sub-Saharan Africa: meeting the challenges of an emerging epidemic

BACKGROUND

Sub-Saharan Africa faces an epidemic of diabetes. Diabetes causes significant morbidity including visual loss from diabetic retinopathy, which is largely preventable. In this resource-poor setting, health systems are poorly organized to deliver chronic care with multiple system involvement. The specific skills and resources needed to manage diabetic retinopathy are scarce. The costs of inaction for individuals, communities and countries are likely to be high.

DISCUSSION

Screening for and treatment of diabetic retinopathy have been shown to be effective, and cost-effective, in resource-rich settings. In sub-Saharan Africa, clinical services for diabetes need to be expanded with the provision of effective, integrated care, including case-finding and management of diabetic retinopathy. This should be underpinned by a high quality evidence base accounting for differences in diabetes types, resources, patients and society in Africa. Research must address the epidemiology of diabetic retinopathy in Africa, strategies for disease detection and management with laser treatment, and include health economic analyses. Models of care tailored to the local geographic and social context are most likely to be cost effective, and should draw on experience and expertise from other continents. Research into diabetic retinopathy in Africa can drive the political agenda for service development and enable informed prioritization of available health funding at a national level. Effective interventions need to be implemented in the near future to avert a large burden of visual loss from diabetic retinopathy in the continent.

SUMMARY

An increase in visual loss from diabetic retinopathy is inevitable as the diabetes epidemic emerges in sub-Saharan Africa. This could be minimized by the provision of case-finding and laser treatment, but how to do this most effectively in the regional context is not known. Research into the epidemiology, case-finding and laser treatment of diabetic retinopathy in sub-Saharan Africa will highlight a poorly met need, as well as guide the development of services for that need as it expands.

[Pediatric cataract surgery in Malawi]

PURPOSE

The aim of this study was to evaluate the postoperative refractive status after pediatric cataract surgery with age-determined intraocular lens (IOL) implantation in children (age 0-8 years) in Malawi.

MATERIALS AND METHODS

Hospital-based retrospective study from January to June 2011 analyzing age, sex, origin, type of cataract surgery, IOL power and postoperative refractive status. In the absence of biometry, IOL powers were chosen according to the child's age and IOL availability.

RESULTS

A total of 58 eyes from 33 children were surgically treated of which 25 (76%) were bilateral and 8 (24%) unilateral. Best refractive outcome was achieved with a 25 diopter (D) IOL implanted in children 5-8 years old. None of the children aged 1-7 years achieved the previously calculated target refraction. Results showed a marked myopic variability. The range of postoperative refraction was from - 15 D to + 12.5 D and a large number of children (n=11, 33%) did not attend for follow-up.

CONCLUSION

Implanting IOLs according to age groups is not a suitable surgical strategy even in resource-poor settings. Refractive outcomes were too variable with a marked myopic shift. Biometry and keratometry are required in order to undertake pediatric cataract surgery. Developing regional pediatric centres should be a focus of the VISION 2020 initiative.

Teaching corner: Regional anaesthesia for ophthalmic surgery

Performing safe and effective regional anaesthesia for ophthalmic surgery is an important skill for anaesthetic and ophthalmologic practitioners. Akinetic sharp-needle blocks are generally safe but rare, sight and life threatening complications occur. Sub-Tenon's block using a blunt canula provides akinesa and is a safer alternative but serious complications have been reported. This review provides an introduction to the relevant anatomy, local anaesthetic drugs and commonly used techniques and a practical guide to their safe performance.

Inappropriate enrollment of children in schools for the visually impaired in east Africa

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.

Causes of severe visual impairment and blindness in children in schools for the blind in eastern Africa: changes in the last 14 years

PURPOSE

To determine the causes of severe visual impairment and blindness in children attending schools for the blind in Kenya, Malawi, Uganda, and Tanzania and to compare the findings with those of a 1994 study.

METHODS

Children attending schools for the blind or annexes in 4 eastern African countries were examined. The major anatomical site of and underlying etiology of severe visual impairment and blindness was recorded using the standardized World Health Organization (WHO) reporting form.

RESULTS

A total of 1062 children aged below 16 years were examined of whom 701 (65.2%) had severe visual impairment or blindness. The major anatomical sites of visual loss overall (% and 95% CI) were cornea scar/phthisis bulbi (19%,16.1-21.9), whole globe lesions (15.7%,13.0-18.4), retina (15.4 %, 12.7-18.1), lens related disorders (13.1%, 10.7-15.5), and optic nerve disorders (12.3%, 9.9-14.7). Corneal scar/phthisis was not distributed equally among the countries and was highest in Malawi, similar to findings in 1995. The major etiology of visual loss was childhood factors (29.9%) and an estimated 40% of severe visual impairment and blindness was due to potentially avoidable causes.

CONCLUSION

The major causes of severe visual impairment and blindness overall have not changed appreciably since 1995. There are important differences among countries, however, and using overall estimates for planning may be misleading.

Cataract in children attending schools for the blind and resource centers in eastern Africa

OBJECTIVE

The aim of this study was to describe results of a representative sample of children who have undergone cataract surgery in schools for the blind in 4 African countries.

DESIGN

Cross-sectional study.

PARTICIPANTS

Children enrolled at schools for the blind in Kenya, Malawi, Tanzania, and Uganda.

METHODS

We used a population-proportional-to-size methodology to select a representative sample of schools for the blind and annexes and included all the children attending the selected schools. Trained teams using standardized examination methods and a modified World Health Organization form examined the children. The form was modified specifically to collect information on outcomes of cataract surgery.

MAIN OUTCOME MEASURES

Operative status and postoperative visual acuity.

RESULTS

Of 1062 children examined, 196 (18%) had undergone cataract surgery or had cataract as the major cause of visual impairment; 140 (71%) had bilateral surgery, 24 (12%) had unilateral surgery, and 32 (16%) had not had surgery. Of operated eyes, 118 (41%) had visual acuity > or =20/200. Intraocular lenses were implanted in 65% of the operated eyes. Eyes with intraocular lens were more likely to have better vision than those without (P for trend = 0.04). Amblyopia was the most common cause of poor visual acuity in children who had undergone cataract surgery.

CONCLUSIONS

The number of children in the schools who receive cataract surgery has increased greatly since 1995. The high rate of amblyopia highlights the critical need for programs to find children earlier and to ensure adequate follow-up after surgery. Without such programs, the value of training pediatric surgeons will not be fully realized.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any materials discussed in this article.