Estimating numbers of blind children for planning services: findings in Kilimanjaro, Tanzania

Functional Vision of Pseudophakic Children Attending a Pediatric Ophthalmology Clinic in Southwest Nigeria

PURPOSE

To determine the functional vision of pseudophakic children attending a child eye health tertiary facility in southwest Nigeria.

METHODS

A hospital-based descriptive study of pseudophakic children attending the Pediatric Ophthalmology outpatient clinic of a tertiary facility in southwest Nigeria was conducted between June and November 2021. Details of demography and clinical examination findings were obtained using a semi-structured questionnaire. Information about functional vision was obtained using the Pediatric Eye Questionnaire (PedEyeQ). Data obtained from the PedEyeQ were entered into a Rasch-calibrated PedEyeQ Excel response data sheet. Data analysis was done using Statistical Package for Social Sciences (SPSS) software version 22 (SPSS, Inc).

RESULTS

A total of 196 pseudophakic children were recruited. Their ages ranged from 2 to 16 years with a mean of 9.8 ± 3.4 years and there was a male-to-female ratio of 2.2:1. The median functional vision score of pseudophakic children across all age groups was 90.0. The functional vision scores were associated with the laterality of cataract, type of cataract, presence of comorbidities, visual acuity (distance and near) in the better eye, and number of surgeries.

CONCLUSIONS

The functional vision scores of pseudophakic children were low. Significant predictors of low functional vision scores include surgery for congenital cataract, low average family income, longer duration of time between surgery and recruitment into the study, and poorer best corrected visual acuity in the better eye. The routine assessment of functional vision should be considered an important aspect of pseudophakic children's eye care with a view toward optimizing psychological and social well-being. [J Pediatr Ophthalmol Strabismus. 2024;61(2):138-146.].

Red reflex examination in reproductive and child health clinics for early detection of paediatric cataract and ocular media disorders: cross-sectional diagnostic accuracy and feasibility studies from Kilimanjaro, Tanzania

BACKGROUND/OBJECTIVES

Late presentation of congenital cataract in the developing world has led to poor outcomes such that cataract is the leading cause of childhood blindness. Our hypothesis was that, sensitivity of red-reflex testing is greater than sensitivity of torchlight examination. We aimed to compare sensitivity of new red reflex screening tools and assess the feasibility of Arclight red reflex screening in the community.

SUBJECT/METHODS

We compared the diagnostic accuracy of four different screening tools for cataract and retinoblastoma performed by ophthalmic nurses, using a clinic based enriched sample of 41 positives and 60 negatives. We then conducted a separate feasibility study, training non-specialist community nurses. Following the training, community nurses examined 2827 children <5 years with Arclight who were attending their clinics for growth monitoring and immunisation.

FINDINGS

Diagnostic accuracy study: estimated sensitivities were 97.6% for Catcam, 92.7% for Arclight, 90.2% for PEEK retina and 7.3% for torchlight. Estimated specificities were above 90% for Catcam, Arclight and torchlight and 87% for PEEK retina. Feasibility study: twenty-four out of 2728 children screened failed community screening, seven were true positive (six cataract, one retinoblastoma). Prevalence of bilateral cataract was 1.5/1000 (95% CI: 0.40-3.75 per 1000).

CONCLUSIONS

Arclight and CatCam have higher sensitivity than torchlight, are easy to learn and use by primary health care nurses. Red reflex testing should be recommended in the WHO guidelines instead of torchlight examination to help early detection of potential blinding causes including congenital cataract and retinoblastoma.

Epidemiology of Childhood Blindness and Low Vision in Kinshasa-democratic Republic of the Congo

Purpose: To determine the magnitude and causes of blindness and low vision in children in Kinshasa.Methods: A study was conducted to carry out a survey in 96 health areas in Kinshasa city. Children aged less than 16 years old with supposed visual problems (Visual acuity < 6/18) were identified by volunteers and surveyors in households and were thereafter examined by two ophthalmologists. Prevalence and causes of blindness and low vision were determined. For each child, anatomic sites of abnormality, etiologic factors and avoidable causes responsible for visual impairment were considered.Results: Thirty-six children with bilateral visual impairment were identified, including 10 cases of blindness and 26 cases of low vision. The prevalence of blindness and low vision was, respectively, 0.08% [95% CI 0.04-0.14] and 0.19% [95% CI 0.13-0.28].Optic nerve and whole globe were the main anatomical sites responsible for blindness in, respectively, in 30% and 20%. Optic nerve atrophy and glaucoma were the leading causes of childhood blindness. The globe apparently normal (50%), uvea (12%) and cornea (12%) were the most common anatomic site responsible for low vision with refractive errors (42%) and uveitis (12%) as the main causes. Childhood and hereditary factors accounted for, respectively, 16.7% and 13.9% of low vision cases. Visual impairment was due to avoidable causes in 69.4% of children.Conclusion: Damage to the optic nerve and refractive errors were respectively the maincauses of blindness and low vision among children in Kinshasa.

Pediatric Case Finding in Madagascar: A Controlled, Prospective Population-based Assessment of Key Informant Productivity and Cost

Purpose: The Key Informant (KI) case finding method, which trains community members to screen children for eye problems and refer them to eye services, is a common strategy to identify and refer children with blindness and visual impairment. However, studies to date have not determined the benefit and cost of adding KIs to routine outreach activities.Methods: Four eye programs in Madagascar with established outreach camps added KIs to a portion of their camps distributed equally throughout their service region over a one year period. KIs recorded children screened and their attendance at an outreach camp. Outreach personnel used standardized registration forms to gather age, sex, visual acuity, diagnosis and treatment data. Costs were gathered for the KI program and outreach camps.Results: In one year, the 4 eye programs held 138 outreach camps, 43 with KIs. The KI camps were more productive than regular camps seeing an average of 61 and 24 children and 50 and 19 children with an eye problem, for KI and regular camps, respectively. The KI camps also saw more children with moderate or severe visual impairment or blindness with 21 and 8 children (per 10 camps) for KI and regular camps, respectively. A KI camp cost $463 ($642 vs. $179) more than a regular camp and $3 ($8 vs. $11) more per child seen.Conclusion: The KI method significantly increased the number of children attending outreach camps, at all levels of visual impairment and blindness, at a modest increase in costs.

Childhood blindness and visual impairment in the Narayani Zone of Nepal: a population-based survey

Purpose: To estimate the prevalence and causes of blindness (BL), severe visual impairment (SVI), moderate visual impairment (ModVI) and mild visual impairment (MildVI) in children in Narayani Zone, Nepal. Methods: In 2017, 100 population clusters within the Narayani Zone of Nepal were selected using RAAB software. Children (aged 0-15 years) suspected of having visual problems were identified using Key Informants (KIs) and school teachers and were referred for ophthalmologic examination. Eye care staff actively sought children who failed to present for examination. Causes of BL/SVI/ModVI/MildVI were categorized using standard World Health Organization definitions. Results: Of 76,588 children selected, 72,900 (95%) were screened. Of 2,158 children referred for examination, 1,322 were referred by teachers and 836 by KIs. A total of 1,617 (75%) children received a detailed examination, of whom 128 children [65 girls (51%)] mean age of 9.4 (± 4.1 years) were confirmed to have BL 7 (5.5%), SVI 16 (12.5%), ModVI 19 (15%) or MildVI 86 (67%). The combined prevalence of BL/SVI/ModVI/MildVI was 175/100,000 (95% CI 172-178/100,000); BL/SVI/ModVI was 55/100,000 (95% CI 53-57/100,000) and the combined BL/SVI estimate was 30/100,000 (95% CI 29-31/100,000). The leading causes of BL/SVI/MVI were refractive error 23 (55%) and whole globe disorders 5 (12%). Total avoidable causes were 31 (74%). Conclusion: The prevalence of BL/SVI/ModVI among children in Narayani Zone was moderate and included a high proportion of avoidable and treatable cases. Pediatric ophthalmic services need improvement, mainly refractive error correction in rural areas of Nepal.

Prevalence and causes of childhood blindness in Huidong County, South China, primary ascertained by the key informants

Purpose

The aim of this study is to ascertain the prevalence and causes of childhood blindness and severe visual impairment (BL/SVI) in Huidong, South China.

Methods

This cross-sectional study was conducted in early 2017 in areas of 139 816 children at the age of 0–15 as the study subjects. We used the trained key informants (KIs) to do preliminary visual test in the communities and refer those children suspected with blindness or unable to count fingers with both eyes at 5 m to hospital for further examination by paediatric ophthalmologist for causes. The WHO’s definition of BL/SVI was used, as blindness is best-corrected visual acuity worse than 0.05 in better eye and SVI is equal to or better than 0.05 but worse than 0.1 in better eye.

Results

Three hundred and fourteen KIs were trained. In total, 42 children with BL/SVI were found, and among them over half (22, 52.4%) were due to posterior segment disorders by anatomic site and 18 (42.9%) children were potentially preventable; these included BL/SVI caused by factors at children’s development in intrauterine and after birth. This established the prevalence of BL/SVI was at 0.31/1000 (95% CI 0.28 to 0.34/1000).

Conclusion

A low prevalence of childhood blindness was documented in this study. Establishment of surveillance system for disabled children including those with BL/SVI and better health education on eye care to the public according to the surveillance outcomes would help to reduce avoidable children’s BL/SVI further in China.

Using Key Informant Method to Determine the Prevalence and Causes of Childhood Blindness in South-Eastern Nigeria

PURPOSE

To determine the prevalence and causes of childhood blindness in an underserved community in south-eastern Nigeria using the key informant method.

METHODS

This was a descriptive cross-sectional study. Key informants (KI) appointed by their respective communities received 1-day training on identification of blind children in their communities. Two weeks later, the research team visited the agreed sites within the community and examined the identified children. The World Health Organization eye examination record for blind children was used for data collection. Data entry and analysis were done with the Statistical Package for Social Sciences (SPSS) version 17.0.

RESULTS

Fifteen blind or severely visually impaired children (age range 3 months to 15 years) were identified in this community; nine of these were brought by the KIs. The prevalence of childhood blindness/severe visual impairment (BL/SVI) was 0.12 per 1000 children. By anatomical classification, operable cataract in 6 (40.0%) was the leading cause of BL/SVI in the series; followed by optic nerve lesions (atrophy/hypoplasia) in 3 (20.0%). The etiology of BL/SVI is unknown for the majority of the children (66.7%). It was presumed hereditary in four children (26.7%). Sixty percent of the blindness was judged avoidable. Only three children (20.0%) were enrolled in the Special Education Centre for the Blind.

CONCLUSION

The prevalence of childhood BL/SVI in our study population is low but over half of the blindness is avoidable. There may be a significant backlog of operable childhood cataract in south-eastern Nigeria. The KI method is a practical method for case finding of blind children in rural communities.

The Use of Key Informant Method for Identifying Children with Blindness and Severe Visual Impairment in Developing Countries

PURPOSE

An estimated 19 million children are visually impaired; of these, 1.4 million are irreversibly blind. A key challenge is to identify them early in life to benefit maximally from visual rehabilitation, and/or treatment. This aggregative review and structured literature analysis summarizes evidence of what it is about the key informant (KI) approach that works to identify children with blindness or severe visual impairment (B/SVI) in the community (for whom, to what extent, in what circumstances, in what respect, how and why).

METHODS

Peer-reviewed (PubMed, hand search) and grey literature (Google, World Health Organization website, academic theses, direct requests) were included, and methods and criteria used for identification, productivity (number of children referred per KI), accuracy of referrals (positive predictive value, PPV), age of children with B/SVI, KI definition, sex, information about cost and comparisons aggregated.

RESULTS

We included 31 documents describing 22 unique KI programs. Mostly KIs identified children with B/SVI in 1-3 weeks, i.e. "campaign mode." In 60%, KIs were community volunteers, others formal health sector workers (FHSW). Around 0.02-1.56 children per KI (median = 0.25) were successfully recruited. PPV ranged from 12 to 66%. In two studies comparing FHSWs and community KIs, the latter were 8 and 10 times more productive.

CONCLUSION

KIs working in campaign mode may provide an effective approach to identifying children with B/SVI in communities. Including identification of ocular problems and/or other impairments has been recommended. Research on factors that influence effectiveness and on whether KIs continue to contribute could inform programs.

Quality of life and functional vision concerns of children with cataracts and their parents

PurposeTo identify specific health-related quality of life (HRQOL) and functional vision concerns affecting children with cataracts and common associated conditions as expressed by children or one of their parents (proxy), and HRQOL concerns affecting the parents themselves.MethodsIndividual semi-structured interviews were conducted with parents of children with cataracts (N=31) and with the children themselves (ages 5-17 years; N=16). Transcripts of recorded interviews were evaluated using NVivo software. Specific concerns were identified and coded, and broad themes were identified. The frequency of each theme was calculated, with the frequency of specific concerns within each theme.ResultsRegarding the child's experience, 6 themes were identified: Visual Function (mentioned by 16 of 16 children (100%) and by 26 of 31 parents (84%), Social (94 and 65%), Treatment (81 and 90%), Worry (75 and 10%), Emotions (63 and 68%), and Physical Discomfort (63 and 26%). Worry showed the largest discrepancy between child and their parent; although 75% children reported Worry, only 6% of parents reported that their child experienced Worry (P=0.0009). Regarding the parents' own experience, 5 themes were identified: Worry (100%), Compensation for Condition (100%), Treatment (94%), Emotions (90%), and Affects Family (52%).ConclusionsA wide range of concerns were identified from interviews of children with cataracts and their parents. Concerns reflect the impact of cataracts in physical, emotional, and social domains, and specific concerns will be used for the development of questionnaires to quantify the quality of life and functional vision effects of cataracts.

Global prevalence of childhood cataract: a systematic review

Childhood cataract is an avoidable cause of visual disability worldwide and is a priority for VISION 2020: The Right to Sight. There is a paucity of information about the burden of cataract in children and the aim of this review is to assess the global prevalence of childhood cataract. The methodology for the review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We performed a literature search for studies reporting estimates of prevalence or incidence of cataract among children (aged<18 years) at any global location using the Cochrane Library, Medline and Embase up to January 2015. No restrictions were imposed based on language or year of publication. Study quality was assessed using a critical appraisal tool designed for systematic reviews of prevalence. Twenty prevalence and four incidence studies of childhood cataract from five different geographical regions were included. The overall prevalence of childhood cataract and congenital cataract was in the range from 0.32 to 22.9/10000 children (median=1.03) and 0.63 to 9.74/10000 (median=1.71), respectively. The incidence ranged from 1.8 to 3.6/10000 per year. The prevalence of childhood cataract in low-income economies was found to be 0.42 to 2.05 compared with 0.63 to 13.6/10000 in high-income economies. There was no difference in the prevalence based on laterality or gender. This review highlights substantial gaps in the epidemiological knowledge of childhood cataract worldwide, particularly from low and lower middle-income economies. More studies are needed using standard definitions and case ascertainment methods with large enough sample sizes.

Comparing key informants to health workers in identifying children in need of surgical eye care services

The objective of the study was to compare the productivity of key informants (KIs) and dedicated health workers (HWs) in identifying children with surgical eye care needs. In two regions of Tanzania, KIs and HWs were trained to identify and register children with severe visual impairment or blindness, with the objective of providing them with surgical eye care services. Identified children were examined at predetermined sites. The total numbers of children in need of surgical services identified by KIs and HWs were compared to measure their relative efficacy. A total of 197 KIs and 63 HWs were trained in the two regions. Five hundred and forty-nine children were identified by KIs and 22 children were identified by HWs: KIs were three times more productive than the HWs. Most of the children identified and examined had serious eye pathology and received surgery or low vision services. The cost per child found was significantly less for children found by KI compared to HW. The study indicates that, in rural Africa, finding children in need of surgical and low vision interventions and ensuring that they are properly screened appears to require community-based efforts.

Challenges faced by key informants practicing case finding for vision loss in children: the experience in Cross River State, Nigeria

BACKGROUND

To identify challenges faced by key informants (KIs) in a childhood blindness and severe visual impairment survey in Cross River State (CRS), Nigeria.

METHODS

Based on eligibility 742 KIs were selected by their village/clan heads in the 18 local government areas (LGAs) of Cross River State. After training in each LGA, KIs were to identify children with visual problems. KIs used a number of methods to identify children with vision loss. After the case detection period, KIs were requested to bring children suspected of vision problems to a central site for examination. Following this, an interviewer-administered semi-structured interview was used to obtain information from the KIs. Thematic content analysis was used to identify these challenges.

RESULTS

Among the 742 KIs, 642 did not provide any comment on challenges during interview; 100 KIs reported challenges. Major challenge themes identified were issues related to the family of the child and issues related to operational conditions, principally transportation, communication, and incentives.

CONCLUSIONS

It is likely that challenges were under-reported. Research is needed to understand why some parents feel stigmatized by having children with vision problems. Community based programmes need to strengthen community awareness, address trust issues, and ensure transportation and communication are improved in order to enhance programme success.

Childhood cataract in sub-Saharan Africa

Investment by organizations and agencies has led to a growing body of evidence and information to assist ophthalmologists and others to meet the needs of children with cataract in Africa. The geographic distribution of research, training, and programme development across Africa has been uneven; investment has been greatest in eastern and southern Africa. Population based surveys (using key informants) suggest that 15-35% of childhood blindness is due to congenital or developmental cataract. There may be up to 82,000 children with non-traumatic cataract in Africa, with approximately 19,000 new cases each year. Effective strategies to find and refer children are those that engage the community in case detection. Identification and referral does not automatically mean surgical intervention with distance to the surgical facility being the most common reason for failure to seek care. Surgical management has become more specialized and a team based approach has been adopted by many paediatric ophthalmologists and their programmes. Although many children still present late for surgery, outcomes of surgery are much improved from previous experiences. Research suggests that post-operative follow up, still a challenge, can be improved through adoption of specific strategies. There has been limited success in ensuring that children are placed in appropriate educational settings. While eye care professionals may feel their responsibility ends with clinical care, it is important for the paediatric eye care team to be engaged with educational and rehabilitation services.

Using key informants to estimate prevalence of severe visual impairment and blindness in children in Cross River State, Nigeria

PURPOSE

To assess the prevalence and causes of childhood blindness in Cross River State, Nigeria, using the key informant (KI) method.

METHODS

KIs were selected and trained and requested to bring children to identified facilities 2 weeks after training for examination by a specialist team. Visual acuity and cause of impaired acuity were assessed. Children at a Cross River State school for the blind were also assessed. An estimated prevalence of childhood blindness and severe visual impairment (BL/SVI) in the Cross River State was calculated.

RESULTS

A total of 742 KIs were included. The prevalence of BL/SVI in Cross River State was estimated to be 0.09-0.22 per 1,000 children. The three most common anatomic causes are lens related (35%), whole globe (19.4%), and corneal (15.7%), most of which are avoidable.

CONCLUSIONS

The prevalence of childhood BL/SVI in Cross River State was somewhat lower than expected but similar to other recent reports from Africa. Lens-related causes were the most common. KIs performed well, ensuring that many children in need of eye services were examined.

An update on progress and the changing epidemiology of causes of childhood blindness worldwide

PURPOSE

To summarize the available data on pediatric blinding disease worldwide and to present current information on childhood blindness in the United States.

METHODS

A systematic search of world literature published since 1999 was conducted. Data also were solicited from each state school for the blind in the United States.

RESULTS

In developing countries, 7% to 31% of childhood blindness and visual impairment is avoidable, 10% to 58% is treatable, and 3% to 28% is preventable. Corneal opacification is the leading cause of blindness in Africa, but the rate has decreased significantly from 56% in 1999 to 28% in 2012. There is no national registry of the blind in the United States, and most schools for the blind do not maintain data regarding the cause of blindness in their students. From those schools that do have such information, the top three causes are cortical visual impairment, optic nerve hypoplasia, and retinopathy of prematurity, which have not changed in past 10 years.

CONCLUSIONS

There are marked regional differences in the causes of blindness in children, apparently based on socioeconomic factors that limit prevention and treatment schemes. In the United States, the 3 leading causes of childhood blindness appear to be cortical visual impairment, optic nerve hypoplasia, and retinopathy of prematurity; a national registry of the blind would allow accumulation of more complete and reliable data for accurate determination of the prevalence of each.

Prevalence and causes of blindness in children in Vietnam

OBJECTIVE

To estimate the prevalence of blindness in children in Vietnam and to assess the major causes.

DESIGN

A population-based study sampled children from 16 provinces across Vietnam. The second study examined children attending all blind schools in Vietnam.

PARTICIPANTS

In 16 provinces, 28 800 children aged 0-15 were sampled. In 28 blind schools, 569 children aged 0-15 were examined.

INTERVENTION

In children not seeing well according to the parents, presenting visual acuity (PVA) was assessed. If PVA was <3/60 in one or both eyes, the child was examined by an ophthalmologist. All children in blind schools were examined by a pediatric ophthalmologist.

MAIN OUTCOME MEASURES

Blindness was defined as PVA <3/60 in the better eye. Causes of visual loss were classified using the World Health Organization classification.

RESULTS

In the population-based study, 22 children had a PVA <3/60 in the better eye, a prevalence of 7.6/10 000 children (95% confidence interval [CI], 4.9-11.8/10 000). Fourteen children had a pinhole visual acuity <3/60 in the better eye, a prevalence of 4.9/10 000 (95% CI, 2.8-8.4/10 000). An estimated 16 400 (95% CI, 10 500-25 300), children were blind from all causes, with 36.4% from uncorrected refractive errors. In the blind schools, 411 children had a PVA <3/60 in the better eye and 55.5% were male. Conditions of the retina (24.6%) and cornea (24.0%) predominated. Retinopathy of prematurity (ROP) caused blindness in 32.6% of children younger than 10 years, but in only 6% of older children. The converse was true for corneal scarring and phthisis (14.0% and 27.3%, respectively). All other causes were similar between age groups (53.5% and 66.7%, respectively). More than half of all causes were avoidable.

CONCLUSIONS

Vietnam is developing very rapidly, and this is impacting health indices. The mortality rate of those younger than 5 years declined from 65/100 live births in 1980 to 14/100 in 2008. The findings of this study show these changes, because the childhood blindness prevalence was relatively low, and the causes show improved control of measles and vitamin A deficiency, as well as increased services for premature babies. Eye care services for children should now focus on refractive errors, cataract, and control of ROP.

Disability and rehabilitation in Tanzania: a review of the literature

PURPOSE

This scoping review outlines recently published information available about disability prevalence and management, as well as environmental conditions and the rehabilitation context in the country of Tanzania. The information is presented from diverse sources including research articles, government documents and reports from international development agencies.

METHOD

Documents for this review were located using four search strategies; a search of electronic databases, contact with key informants, a reference list search of articles selected for review and a search of key websites. The documents were classified based on the format and focus of the material, while the information was organised into qualitative themes based upon the research objectives to present a descriptive overview on this topic.

FINDINGS

The findings of this study confirmed the lack of information available about the profile of disabilities, with evidence suggesting that disabilities are not satisfactorily managed in Tanzania; however, environmental conditions were found to be well documented. Several environmental supports and barriers for people with disabilities were described.

CONCLUSION

The findings of this review indicate a need to further develop rehabilitation service provisions in Tanzania to improve the management of disabilities.

Blindness in childhood in developing countries: time for a reassessment?

Paul Courtright and colleagues argue that the changing patterns of global childhood blindness suggest a need to reassess research, training, and programmatic requirements.