Incidence of registered visual impairment in the Nordic child population

Cerebral visual impairment in children: Multicentric study determining the causes, associated neurological and ocular findings, and risk factors for severe vision impairment

Purpose

To evaluate the causes, associated neurological and ocular findings in children with cerebral visual impairment (CVI), and to identify risk factors for severe vision impairment.

Methods

A multicenter, retrospective, cross-sectional analysis was carried out from January 2017 to December 2019 on patients less than 16 years of age with a diagnosis of CVI.

Results

A total of 405 patients were included of which 61.2% were male and 38.8% were female. The median age at presentation was 4 years (range 3 months to 16 years). Antenatal risk factors were present in 14% of the cases. The most common cause of CVI was hypoxic-ischemic encephalopathy (35.1%), followed by seizure associated with brain damage (31.3%). The most common neurological finding was seizure (50.4%), followed by cerebral palsy (13.6%). Associated ophthalmological findings were significant refractive error (63.2%), esotropia (22.2%), exotropia, (38%), nystagmus (33.3%), and optic nerve atrophy (25.9%). Severe visual impairment (<20/200) was associated with optic atrophy (odds ratio: 2.9, 95% confidence interval: 1.4-6.0; P = 0.003) and seizure disorder (odds ratio: 1.9, 95% confidence interval: 1.2-3.3; P = 0.012).

Conclusion

The various ophthalmic, neurological manifestations and etiologies could guide the multidisciplinary team treating the child with CVI in understanding the visual impairment that affects the neuro development of the child and in planning rehabilitation strategies.

Childhood visual impairment and blindness: 5-year data from a tertiary low vision center in Israel

BACKGROUND

To assess the main causes leading to childhood visual impairment/blindness in a center for low vision in Israel and to analyze the literature on pediatric blinding diseases in developed countries.

METHODS

Retrospective study based on observational case series. Data were obtained from medical records of visually impaired children, seen at a national referral low vision center. Children were divided into two groups: moderate visual impairment (6/18 to 6/60) and severe visual impairment (SVI)/blindness (<6/60). Inherited eye diseases (IED) were grouped together for analysis. Data from the Israeli blind registry from the same period of time were analyzed for comparison. A review of literature on childhood blindness in developed countries since 2000 was conducted.

RESULTS

A total of 1393 children aged 0-18 years were included in the study. Moderate visual impairment was seen in 1025 (73.6%) and SVI/blindness in 368 (26.4%) of the studied children. Among blind children, IED accounted for at least 51% of all diagnoses, including mainly albinism and retinal dystrophies. IED prevalence was equally high in both main ethnic groups (Jewish and Arab Muslims). Non-IED (22.6%) included mainly patients with cerebral visual impairment and retinopathy of prematurity.

CONCLUSIONS

The leading cause of childhood visual impairment and blindness in our patient cohort was IED. Analyses of the literature from the last two decades show that IED are a major cause for SVI/childhood blindness in other developed countries as well. Updated patterns of global childhood blindness may suggest a need for new approach for screening programs and modern tactics for prevention.

The Multidisciplinary Guidelines for Diagnosis and Referral in Cerebral Visual Impairment

Introduction

Cerebral visual impairment (CVI) is an important cause of visual impairment in western countries. Perinatal hypoxic-ischemic damage is the most frequent cause of CVI but CVI can also be the result of a genetic disorder. The majority of children with CVI have cerebral palsy and/or developmental delay. Early diagnosis is crucial; however, there is a need for consensus on evidence based diagnostic tools and referral criteria. The aim of this study is to develop guidelines for diagnosis and referral in CVI according to the grade method.

Patients and Methods

We developed the guidelines according to the GRADE method 5 searches on CVI (children, developmental age ≤ 18 years) were performed in the databases Medline, Embase, and Psychinfo, each with a distinct topic.

Results

Based on evidence articles were selected on five topics: 1. Medical history and CVI-questionnaires 23 (out of 1,007). 2. Ophthalmological and orthoptic assessment 37 (out of 816). 3. Neuropsychological assessment 5 (out of 716). 4. Neuroradiological evaluation and magnetic resonance imaging (MRI) 9 (out of 723). 5. Genetic assessment 5 (out of 458).

Conclusion

In medical history taking, prematurity low birth weight and APGAR (Appearance, Pulse, Grimace, Activity, Respiration) Scores (<5) are important. Different questionnaires are advised for children under the age of 3 years, older children and for specific risk groups (extremely preterm). In ophthalmological examination, eye movements, specially saccades, accommodation, crowding, contrast sensitivity and visual fields should be evaluated. OCT can show objective signs of trans-synaptic degeneration and abnormalities in fixation and saccades can be measured with eye tracking. Screening of visual perceptive functioning is recommended and can be directive for further assessment. MRI findings in CVI in Cerebral Palsy can be structured in five groups: Brain maldevelopment, white and gray matter lesions, postnatal lesions and a normal MRI. In children with CVI and periventricular leukomalacia, brain lesion severity correlates with visual function impairment. A differentiation can be made between cortical and subcortical damage and related visual function impairment. Additional assessments (neurological or genetic) can be necessary to complete the diagnosis of CVI and/or to reveal the etiology.

The Global Prevalence of Amblyopia in Children: A Systematic Review and Meta-Analysis

Epidemiological data about the prevalence of amblyopia around the world vary widely among regions and periods. This meta-analysis aimed to determine the global prevalence of amblyopia in children. PubMed, Embase, and the Cochrane Library were searched for prevalence studies published up to 5 November 2021. The outcome was the prevalence of amblyopia, analyzed as pooled estimates with 95% confidence intervals (CI). A total of 97 studies were included, including 4,645,274 children and 7,706 patients with amblyopia. The overall worldwide pooled prevalence of amblyopia was 1.36% (95%CI: 1.27-1.46%). The prevalence of amblyopia was higher in males (1.40%, 95%CI: 1.10-1.70%) than in females (1.24%, 95%CI: 0.94-1.54%) (OR = 0.885, 95%CI: 0.795-0.985, P = 0.025). The results of the meta-regression analysis showed that there were no significant associations between the prevalence of amblyopia and geographical area, publication year, age, sample size, and whether it was carried out in a developed or developing country (all P > 0.05). Begg's test (P = 0.065) and Egger's test (P < 0.001) showed that there was a significant publication bias in the prevalence of amblyopia. In conclusion, amblyopia is a significant vision problem worldwide, and public health strategies of early screening, treatment, and management are important.

The impact of premature extrauterine exposure on infants' stimulus-evoked brain activity across multiple sensory systems

Prematurity can result in widespread neurodevelopmental impairment, with the impact of premature extrauterine exposure on brain function detectable in infancy. A range of neurodynamic and haemodynamic functional brain measures have previously been employed to study the neurodevelopmental impact of prematurity, with methodological and analytical heterogeneity across studies obscuring how multiple sensory systems are affected. Here, we outline a standardised template analysis approach to measure evoked response magnitudes for visual, tactile, and noxious stimulation in individual infants (n = 15) using EEG. By applying these templates longitudinally to an independent cohort of very preterm infants (n = 10), we observe that the evoked response template magnitudes are significantly associated with age-related maturation. Finally, in a cross-sectional study we show that the visual and tactile response template magnitudes differ between a cohort of infants who are age-matched at the time of study but who differ according to whether they are born during the very preterm or late preterm period (n = 10 and 8 respectively). These findings demonstrate the significant impact of premature extrauterine exposure on brain function and suggest that prematurity can accelerate maturation of the visual and tactile sensory system in infants born very prematurely. This study highlights the value of using a standardised multi-modal evoked-activity analysis approach to assess premature neurodevelopment, and will likely complement resting-state EEG and behavioural assessments in the study of the functional impact of developmental care interventions.

Assessment of quality of life, mental health and ocular morbidity in children from schools for the blind in North-East India

Purpose:

The aim of this study was to describe causes of severe visual impairment and blindness (SVI/BL), and assess the mental health and quality of life of children in schools for the blind in North-East India in two phases.

Methods:

A total of 515 children were examined in 17 schools for the blind in the first phase of study across eight states in North-East India, 6 in Assam, 2 each in Meghalaya, Manipur, Mizoram, and Tripura, 1 each in Arunachal Pradesh, Nagaland, and Sikkim. WHO/PBL eye examination record was used to document findings. In the second phase of study, mental health and quality of life were objectively measured using depression anxiety stress scales (DASS) and low-vision quality of life (LVQOL) questionnaires in 442 children.

Results:

Approximately 3.1% of children had SVI and 71.84% of children were blind. Anatomical sites of SVI/BL were the whole globe in 44.85%, cornea in 17.66%, and retina in 11.65% of children. The underlying cause of visual loss was undetermined in 55% of children. Hereditary pattern was observed in 1.35% of cases. Approximately 74.94% of children were either blind or severely visually impaired since birth. DASS score revealed that 56.56% of children manifested some levels of anxiety and stress while 85.52% had some reduction in quality of life.

Conclusion:

A large significant number of these children suffered from potentially preventable and/or treatable cause of SVI/BL. Though nonvisual factors such as physical and mental health were strong predictors of quality of life, this study proves that visual impairment also plays a considerable role in one's quality of life in a population with low vision.

Ocular Disorders among Preschool Children in Southwest Nigeria

PURPOSE:

The aim of the study was to determine the prevalence and causes of ocular disorders among preschool children.

METHODS:

A multi-stage random sampling technique was used to select 560 children from a total of 9944 children aged 3–5 years attending nursery schools in the study area. Demographic and other relevant data were collected from the children. They underwent full ophthalmic evaluation including anterior and posterior segment examination as well as cycloplegic autorefraction.

RESULTS:

Out of the 560 children screened, 170 (30.3%) were 3 years old, 183 (32.7%) were 4 years old, while the remaining 207 (37.0%) were 5 years old. Male-to-female ratio was 1:1.1. Visual acuity was testable using Lea symbol chart in 90% of the children. Ocular disorders were found in 61 eyes of 35 children giving a prevalence of 6.3%. The most common ocular disorder among participants was refractive error (3.9%), followed by allergic conjunctivitis (1.3%). Other identified ocular disorders were strabismus (0.9%), congenital cataract (0.4%), congenital ptosis (0.4%), optic atrophy (0.4%), ectopia lentis (0.2%), and phthisis bulbi (0.2%). There was no statistically significant difference in the distribution of ocular disorders by age or gender.

CONCLUSION:

Screening is useful in early detection and treatment of ocular disorders in preschool children. Uncorrected refractive error which was identified as the major ocular disorder in these children is treatable. Periodic preschool vision screening would reduce the burden of uncorrected refractive error and other ocular disorders which can interfere with the learning skills of young children entering school.

Prevalence, causes and risk factors of reduced VA and persistent reduced VA among preschool children in Eastern China

AIMS

To determine prevalence, causes, and risk factors of reduced uncorrected visual acuity (UCVA), reduced presenting visual acuity (PVA), and persistent reduced visual acuity (VA) among Chinese preschool children.

METHODS

The longitudinal, population-based Nanjing Eye Study (NES) was carried out. Children underwent baseline comprehensive ocular examinations in 2016 (at 48-60 months old) and the follow-up ocular examinations in 2017. A comprehensive questionnaire about children and their families was completed by their legal guardians. For children having reduced PVA at baseline, a follow-up questionnaire about potential factors concerning VA correction was completed. Reduced VA was defined as VA worse than 0.30 logMAR (Snellen equivalent 6/12, 20/40), and persistent reduced VA was defined as reduced PVA in both 2016 and 2017.

RESULTS

Among 1448 participants with both eye examinations and questionnaires completed, prevalence of reduced UCVA, reduced PVA, and persistent reduced VA at age of 60-72 months were 5.94%, 3.04%, and 1.59% respectively. Causes for reduced PVA were refractive error (79.5%), amblyopia (18.2%), and amblyopia combined nystagmus (2.3%). Among 23 children having persistent reduced VA, causes of reduced PVA remained unchanged in 13 children and 4 children developed amblyopia from refractive error. Younger age (OR = 1.09 for each month decrease, p = 0.01) and non-breastfeeding (OR = 2.08, p = 0.03) were risk factors for reduced UCVA. Younger children with reduced UCVA were at higher risk of having reduced PVA (OR = 1.18 for each month decrease, p = 0.04). Children with siblings (OR = 5.95, p = 0.02) were more likely to have persistent reduced VA.

CONCLUSIONS

Future vision health promotion strategies among preschool children should focus on early vision-screening and timely refractive correction. Apart from children of non-breastfeeding mothers, attention should also be paid to children with siblings.

Impact of prematurity on neurodevelopment

The consequences of prematurity on brain functional development are numerous and diverse, and impact all brain functions at different levels. Prematurity occurs between 22 and 36 weeks of gestation. This period is marked by extreme dynamics in the physiologic maturation, structural, and functional processes. These different processes appear sequentially or simultaneously. They are dependent on genetic and/or environmental factors. Disturbance of these processes or of the fine-tuning between them, when caring for premature children, is likely to induce disturbances in the structural and functional development of the immature neural networks. These will appear as impairments in learning skills progress and are likely to have a lasting impact on the development of children born prematurely. The level of severity depends on the initial alteration, whether structural or functional. In this chapter, after having briefly reviewed the neurodevelopmental, structural, and functional processes, we describe, in a nonexhaustive manner, the impact of prematurity on the different brain, motor, sensory, and cognitive functions.

An Examination of 40 Years of Mathematics Education among Norwegian Braille-Reading Students

Introduction

The study presented here estimated the occurrence of braille-reading students in Norway who were educated according to their grade-level progression in mathematics from 1967 to 2007. It also analyzed the association among these students’ progression in mathematics and the causes of visual impairment, the age at which the diagnosis was established, the students’ gender, and the students’ use of reading media (braille as the sole, primary, or secondary literacy medium).

Methods

A retrospective, population-based study design was used. All the students who had received braille education in the past four decades prior to the study were included. The following data were abstracted from each student's records: birth year, country of birth, gender, year diagnosed, diagnosis, type of reading media, and whether the student's education had followed their grade-level progression.

Results

In total, 248 braille-reading students were identified. Of these students, 141 (57%) had been taught mathematics at grade level. In 19 of the 45 principal eye diagnoses that were registered, all the students were educated according to the normative grade progress in mathematics. There were no statistically significant associations between gender and the abstracted variables or between mathematics education and reading media.

Discussion

During the four decades under study, there was some variation in the distribution of different diagnoses. Students with diagnoses related to the central nervous system had a comparatively higher risk of not attaining their normal grade level in mathematics.

Implication for practitioners

Teachers may expect that a braille-reading student will follow his or her grade level in mathematics. It is essential, however, to gain information on the causes of visual impairment, in general, and in cases of the co-occurrence of visual impairment and learning disabilities, in particular. It is essential to document typical learning patterns among braille-reading students and intervention strategies for students with visual impairments and learning disabilities.

Prevalence of reduced visual acuity among preschool children in eastern China and comparison at a 5-year interval

IMPORTANCE

Assessing the prevalence of reduced visual acuity and its change over time has significant public health importance. This study evaluated prevalence of reduce visual acuity in children aged 48-60 months, and compared it with previous data.

BACKGROUND

Previous studies reported prevalence of reduced visual acuity in preschool children, but none has evaluated prevalence change in the same area.

DESIGN

Nanjing Eye Study, a longitudinal population-based study.

PARTICIPANTS

Two thousand three hundred eligible children.

METHODS

Comprehensive eye examinations.

MAIN OUTCOME MEASURES

Uncorrected visual acuity, presenting visual acuity, best-corrected visual acuity, anterior segment and fundus examination, cycloplegic refraction.

RESULTS

Based on the worse and better eye, respectively, 6.8% and 3.5% had reduced uncorrected visual acuity and 4.0% and 1.4% had reduced presenting visual acuity. Compared to rates in the Nanjing Paediatric Vision Project carried out 5 years ago in the same area, the prevalence rates of reduced uncorrected visual acuity were significantly higher (6.8% vs. 5.3%, P = 0.04 for worse eye; 3.5% vs. 2.1%, P = 0.0049 for better eye), but there was no significant increase in rates of reduced presenting visual acuity (4.0% vs. 3.7%, P = 0.63 for better eye; 1.4% vs. 1.7%, P = 0.43 for worse eye). The prevalence rate of glasses prescription is higher in this study (4.5% vs. 3.1%, P = 0.02).

CONCLUSIONS AND RELEVANCE

Prevalence of reduced uncorrected visual acuity increased significantly, indicating that Chinese children are faced with more vision-threatening factors. However, more children with refractive errors got appropriate correction.

Attenuation of Retinal Vascular Development in Neonatal Mice Subjected to Hypoxic-Ischemic Encephalopathy

A significant proportion of children that survive hypoxic-ischemic encephalopathy (HIE) develop visual impairment. These visual deficits are generally attributed to injuries that occur in the primary visual cortex and other visual processing systems. Recent studies suggested that neuronal damage might also occur in the retina. An important structure affecting the viability of retinal neurons is the vasculature. However, the effects of HIE on the retinal neurovasculature have not been systemically evaluated. Here we investigated whether exposure of postnatal day 9 (P9) neonatal mice to HIE is sufficient to induce neurovascular damage in the retina. We demonstrate that the blood vessels on the surface of the retina, from mice subjected to HIE, were abnormally enlarged with signs of degeneration. The intermediate and deep vascular layers in these retinas failed to form normally, particularly in the periphery. All the vascular damages observed here were irreversible in nature up to 100 days post HIE. We also observed loss of retinal neurons, together with changes in both astrocytes and Müller cells mainly in the inner retina at the periphery. Collectively, our findings suggest that HIE results in profound alterations in the retinal vasculature, indicating the importance of developing therapeutic strategies to protect neurovascular dysfunction not only in the brain but also in the retina for infants exposed to HIE.

Sexual assaults in individuals with visual impairment: a cross-sectional study of a Norwegian sample

OBJECTIVE

To examine the prevalence of sexual assaults among individuals with visual impairment (VI) compared with the general population and to investigate the association between sexual assault and outcomes of self-efficacy and life satisfaction.

DESIGN

Cross-sectional interview-based study conducted between February and May 2017.

PARTICIPANTS

A probability sample of adults with VI (≥18 years) who were members of the Norwegian Association of the Blind and Partially Sighted. A total of 736 (61%) members participated, of whom 55% were of female gender. We obtained norm data for sexual assaults from a representative survey of the general Norwegian population.

OUTCOME MEASURES

Sexual assaults (Life Event Checklist for DSM-5), self-efficacy (General Self-Efficacy Scale) and life satisfaction (Cantril's Ladder of Life Satisfaction).

RESULTS

The prevalence of sexual assaults (rape, attempted rape and forced into sexual acts) in the VI population was 17.4% (95% CI 14.0 to 21.4) among women and 2.4% (95% CI 1.2 to 4.7) among men. For women, the VI population had higher rates of sexual assaults across age strata than the general population. For men, no significant differences were found. In the population of people with VI, the risk of sexual assault was greater for those having other impairments in addition to the vision loss. Individuals with VI who experienced sexual assaults had lower levels of self-efficacy (adjusted relative risk (ARR): 0.18, 95% CI 0.05 to 0.61) and life satisfaction (ARR: 0.31, 95% CI 0.19 to 0.50) than others.

CONCLUSIONS

The risk of experiencing sexual assault appears to be higher in individuals with VI than in the general population. Preventive measures as well as psychosocial care for those who have been exposed are needed.

A pilot study regarding basic knowledge of "cortical visual impairment in children" among ophthalmologists

Purpose:

A pilot study was done to evaluate knowledge regarding “cortical visual impairment (CVI) in children” among ophthalmologists.

Methods:

This study was conducted during the annual conference of a zonal ophthalmological society. All ophthalmologists who attended the conference were requested to participate in this study. Those who agreed were given a validated questionnaire to assess knowledge regarding CVI. Cronbach's alpha of the questionnaire was 0.6. Participants were asked to respond to multiple choice questions by choosing the single best option. The responses obtained were then evaluated.

Results:

The total number of registered delegates in the conference was 448. A total of 103 ophthalmologists showed interest to participate in the study with a response rate of 22.9%. Only 89/103 interested delegates were included in the study as remaining were unaware of CVI. No participant gave correct answers to all questions. Although more than 80% of them knew the most common association (87%) and site of pathology (84%), only 52% were sure about clinical features and even lesser respondents (39%) knew that magnetic resonance imaging is the correct investigation of choice. The majority responded correctly that these children need eye examination (89%) and can be managed by rehabilitation through multidisciplinary approach (82%), but only 58% could recognize differential diagnoses and had a correct idea regarding the prognosis of CVI. There was no correlation between the number of patients diagnosed per month by the respondent with knowledge of the disease.

Conclusion:

In this pilot study, ophthalmologists were found to have limited knowledge regarding clinical features, investigation, differential diagnosis, and visual prognosis of CVI in children. There is a need to improve awareness regarding CVI among ophthalmologists.

The efficacy of VIPP-V parenting training for parents of young children with a visual or visual-and-intellectual disability: a randomized controlled trial

Video-feedback Intervention to promote positive parenting-visual (VIPP-V) or visual-and-intellectual disability is an attachment-based intervention aimed at enhancing sensitive parenting and promoting positive parent-child relationships. A randomized controlled trial was conducted to assess the efficacy of VIPP-V for parents of children aged 1-5 with visual or visual-and-intellectual disabilities. A total of 37 dyads received only care-as-usual (CAU) and 40 received VIPP-V besides CAU. The parents receiving VIPP-V did not show increased parental sensitivity or parent-child interaction quality, however, their parenting self-efficacy increased. Moreover, the increase in parental self-efficacy predicted the increase in parent-child interaction. In conclusion, VIPP-V does not appear to directly improve the quality of contact between parent and child, but does contribute to the self-efficacy of parents to support and to comfort their child. Moreover, as parents experience their parenting as more positive, this may eventually lead to higher sensitive responsiveness and more positive parent-child interactions.

Epidemiology of Reduced Visual Acuity among Chinese Multiethnic Students

SIGNIFICANCE

Data regarding the epidemiology of reduced visual acuity (VA) among multiethnic children and adolescents in China are few. Understanding the vision-related health inequalities among different ethnic groups is crucial for health resource allocations and clinical managements for eye diseases.

PURPOSE

We aim to determine the prevalence, main causes, and health inequalities of reduced VA in multiethnic school students in rural China.

METHODS

A school-based eye survey including 7681 multiethnic school students aged 5 to 16 years in the southwestern part of China was conducted. Detailed ocular examinations including VA measurements, ocular motility evaluations, bilateral postcycloplegic refractions, and the assessments of the external eye, anterior segment, media, and retinal fundus were carried out by trained research vision professionals. Visual acuity was measured using a logarithm of the minimum angle of resolution E-chart, and reduced VA was defined as a presenting VA of worse than 20/40. Concentration index was initiatively utilized to measure health inequalities among different ethnic groups.

RESULTS

The prevalence of reduced VA was 11.4 per 100 children (95% confidence interval, 10.7 to 12.1%) based on the worse-seeing eye data. The prevalence of reduced VA increased with increasing age (P < .001 for trend) and was higher among girls compared with boys (P < .0001). Uncorrected refractive error was the principal cause for reduced VA, which accounted for 87.3% of the participants with reduced VA. The concentration index for reduced VA was 0.07 among different ethnic groups.

CONCLUSIONS

Compared with the estimates reported from previous studies on Chinese children and adolescents, a relatively lower prevalence of reduced VA was observed among multiethnic school students in rural China. Ethnic variations and health inequalities of reduced VA were not significant in this study.

A Systematic Review of the Literature on Parenting of Young Children with Visual Impairments and the Adaptions for Video-Feedback Intervention to Promote Positive Parenting (VIPP)

Secure parent-child attachment may help children to overcome the challenges of growing up with a visual or visual-and-intellectual impairment. A large literature exists that provides a blueprint for interventions that promote parental sensitivity and secure attachment. The Video-feedback Intervention to promote Positive Parenting (VIPP) is based on that blueprint. While it has been adapted to several specific at risk populations, children with visual impairment may require additional adjustments. This study aimed to identify the themes that should be addressed in adapting VIPP and similar interventions. A Delphi-consultation was conducted with 13 professionals in the field of visual impairment to select the themes for relationship-focused intervention. These themes informed a systematic literature search. Interaction, intersubjectivity, joint attention, exploration, play and specific behavior were the themes mentioned in the Delphi-group. Paired with visual impairment or vision disorders, infants or young children (and their parents) the search yielded 74 articles, making the six themes for intervention adaptation more specific and concrete. The rich literature on six visual impairment specific themes was dominated by the themes interaction, intersubjectivity, and joint attention. These themes need to be addressed in adapting intervention programs developed for other populations, such as VIPP which currently focuses on higher order constructs of sensitivity and attachment.

Strabismus in patients with cortical visual impairment: outcomes of surgery and observations of spontaneous resolution

PURPOSE

To investigate the rate of spontaneous resolution of strabismus in patients with cortical visual impairment (CVI) at a single center over a 10-year period and to evaluate the success rate of strabismus surgery.

METHODS

The medical records of patients with CVI and strabismus seen between October 2003 and October 2013 were reviewed retrospectively. Patients were classified into 4 outcome groups: (1) those who experienced spontaneous resolution of strabismus, (2) those with persistent strabismus who did not undergo surgery, (3) those who achieved postoperative alignment of ≤10(Δ); and (4) those whose final postoperative alignment was 11(Δ)-25(Δ) or >25(Δ).

RESULTS

A total of 70 patients were included. Of these, 11 patients (16%) experienced spontaneous resolution of strabismus, 27 (38%) were observed without receiving surgery, and 32 (46%) underwent strabismus surgery. Of these 32, 18 (56%) achieved alignment of ≤10(Δ); 9 (28%), alignment of 11(Δ)-25(Δ); and 5 (16%), alignment >25(Δ). The patients who did not undergo surgery were significantly older at presentation (36 months vs 12-15 months; P = 0.03); otherwise, there were no significant differences between groups in age at surgery or spontaneous resolution, type of strabismus, or underlying cause of CVI.

CONCLUSIONS

In our study cohort, a minority of patients with CVI and strabismus (16%) experienced spontaneous resolution of strabismus. Only 16% of patients undergoing surgery had poor final alignment (>25(Δ)). Strabismus surgery can be reasonably successful in properly selected patients with CVI and strabismus. These patients show considerable rates of resolution of their strabismus, either spontaneously or through surgery.

Saccadic vector optokinetic perimetry in children with neurodisability or isolated visual pathway lesions: observational cohort study

BACKGROUND/AIMS

Children and adults with neurological impairments are often not able to access conventional perimetry; however, information about the visual field is valuable. A new technology, saccadic vector optokinetic perimetry (SVOP), may have improved accessibility, but its accuracy has not been evaluated. We aimed to explore accessibility, testability and accuracy of SVOP in children with neurodisability or isolated visual pathway deficits.

METHODS

Cohort study; recruitment October 2013-May 2014, at children's eye clinics at a tertiary referral centre and a regional Child Development Centre; full orthoptic assessment, SVOP (central 30° of the visual field) and confrontation visual fields (CVF). Group 1: age 1-16 years, neurodisability (n=16), group 2: age 10-16 years, confirmed or suspected visual field defect (n=21); group 2 also completed Goldmann visual field testing (GVFT).

RESULTS

Group 1: testability with a full 40-point test protocol is 12.5%; with reduced test protocols, testability is 100%, but plots may be clinically meaningless. Children (44%) and parents/carers (62.5%) find the test easy. SVOP and CVF agree in 50%. Group 2: testability is 62% for the 40-point protocol, and 90.5% for reduced protocols. Corneal changes in childhood glaucoma interfere with SVOP testing. All children and parents/carers find SVOP easy. Overall agreement with GVFT is 64.7%.

CONCLUSIONS

While SVOP is highly accessible to children, many cannot complete a full 40-point test. Agreement with current standard tests is moderate to poor. Abnormal saccades cause an apparent non-specific visual field defect. In children with glaucoma or nystagmus SVOP calibration often fails.

Prevalence and causes of reduced visual acuity among children aged three to six years in a metropolis in China

PURPOSE

To determine the prevalence and possible causes for reduced visual acuity (VA) in preschool children in a metropolis in China.

METHODS

A school-based paediatric eye survey including 5862 preschool children aged three to 6 years was conducted from 2011 to 2012 in Yuhuatai District, Nanjing, China, using an age-stratified random sampling procedure. Clinical examinations including ocular alignment, ocular motility, visual acuity, prism cover test, cycloplegic refraction, stereopsis screening, slit lamp examination and fundus examination were performed by trained study ophthalmologists and optometrists. Reduced VA was defined as presenting VA of worse than 0.30 logMAR (Snellen 6/12 or 20/40), for both better and worse eyes.

RESULTS

5667 (94.8%) children with complete VA data were included in the data analyses. Among them, 208 and 93 had reduced VA in the worse and better eye, respectively. Reduced VA was detected in 3.7% (95% confidence interval [CI] 3.2%-4.2%) in the worse eye and 1.6% (95% CI 1.3%-2.0%) in the better eye. No significant age and gender differences in reduced VA were observed (p > 0.05). Refractive errors and amblyopia were the principal causes for reduced VA in the worse eye which accounted for 66.8% and 32.7% of the total cases with reduced VA, respectively. Astigmatism and hyperopia were the major types of refractive errors causing reduced VA.

CONCLUSIONS

The burden of reduced VA in preschool children in China was similar to that of Asian children of similar ages in the United States. Uncorrected refractive error and amblyopia were the principal causes for reduced VA among preschoolers (aged three to 6 years) in China.

The effectiveness of VIPP-V parenting training for parents of young children with a visual or visual-and-intellectual disability: study protocol of a multicenter randomized controlled trial

BACKGROUND

Visual or visual-and-intellectual disabilities of children make daily interactions more difficult for their parents and may impact the quality of the parent-child relationship. To support these parents, an existing intervention (Video-feedback Intervention to promote Positive Parenting; VIPP; Juffer F, Bakermans-Kranenburg MJ, van IJzendoorn MH, 2008. Promoting positive parenting; an attachment-based intervention. Mahwah, NJ: Lawrence Erlbaum Associates; 2008) was adapted for use with parents of children with a visual or visual-and-intellectual disability (VIPP-V). This attachment-based intervention was hypothesized to support parents' interpretation and understanding of the behavior of their child with a visual or visual-and-intellectual disability and respond to their child's signals in a sensitive way to improve parent-child interaction quality.

METHODS/DESIGN

A randomized controlled trial (RCT) will be conducted to assess the effectiveness of the adapted intervention VIPP-V (Video-feedback Intervention to promote Positive Parenting in parents of children with Visual or visual-and-intellectual disabilities). Parent-child dyads will be randomized into two groups: 50 dyads will receive VIPP-V in combination with care-as-usual and 50 dyads will receive care-as-usual. Families with a child (1-5 years of age) with a visual or visual-and-intellectual disability will be recruited for participation in the study. Primary outcome measures are parental sensitivity and the quality of parent-child interaction. Secondary outcome measures are parental self-efficacy, and parenting stress. To assess feasibility of implementation of the intervention the experiences of early intervention workers with regard to using VIPP-V are assessed. Moderator variables are the child's developmental age, working alliance between parent and VIPP-V intervention worker and empathy of the VIPP-V intervention worker. Data will be collected approximately one week before the intervention starts (T1), one week (T2) and three months (T3) after the intervention. Parent-child dyads in the care-as-usual-only condition will be assessed at the same time points. Both intention-to-treat and completer analyses will be performed.

DISCUSSION

Descriptive findings in pilot cases suggest benefits from VIPP-V, and compatibility with existing services for parents of children with a visual or visual-and-intellectual disability. The current study will provide insight into the effectiveness of this intervention for parents of children with a visual or visual-and-intellectual disability, and, if the intervention is effective, prepare the field for broad-scale implementation.

TRIAL REGISTRATION

Nederlands Trial Register NTR4306 (registered 5 December 2013).

Trends in the incidence and causes of severe visual impairment and blindness in children from Israel

PURPOSE

To describe trends in the incidence and causes of legal childhood blindness in Israel, one of the few countries worldwide that maintain a national registry of the blind.

METHODS

We performed a historical cohort study of annual reports of the National Registry of the Blind (NRB) between 1999 and 2013. All data regarding demographic information, year of registration and cause of blindness of children 0-18 years of age registered for blind certification were obtained from the annual reports of the NRB. Causes of legal blindness analyzed were optic atrophy, retinitis pigmentosa, retinopathy of prematurity (ROP), albinism, other retinal disorders, cataract, and glaucoma. The main outcome measure was the incidence of new cases of certified legal blindness.

RESULTS

The incidence of newly registered legally blind children in Israel almost halved from 7.7 per 100,000 in 1999 to 3.1 per 100,000 in 2013. The decline was mainly attributable to a decreased incidence of blindness resulting from retinitis pigmentosa and ROP. The incidence of registered cases due to cerebral visual impairment increased.

CONCLUSIONS

During the past decade the incidence of severe childhood visual impairment and blindness declined in Israel. A continuous decline in consanguineous marriages among the Jewish and Arab populations in Israel may have contributed to the decrease in the rate of vision loss due to retinitis pigmentosa in children.

Viewing behavior and related clinical characteristics in a population of children with visual impairments in the Netherlands

Children with visual impairments are very heterogeneous in terms of the extent of visual and developmental etiology. The aim of the present study was to investigate a possible correlation between prevalence of clinical risk factors of visual processing impairments and characteristics of viewing behavior. We tested 149 children with visual information processing impairments (90 boys, 59 girls; mean age (SD)=7.3 (3.3)) and 127 children without visual impairments (63 boys and 64 girls, mean age (SD)=7.9 (2.8)). Visual processing impairments were classified based on the time it took to complete orienting responses to various visual stimuli (form, contrast, motion detection, motion coherence, color and a cartoon). Within the risk group, children were divided into a fast, medium or slow group based on the response times to a highly salient stimulus. The relationship between group specific response times and clinical risk factors was assessed. The fast responding children in the risk group were significantly slower than children in the control group. Within the risk group, the prevalence of cerebral visual impairment, brain damage and intellectual disabilities was significantly higher in slow responding children compared to faster responding children. The presence of nystagmus, perceptual dysfunctions, mean visual acuity and mean age did not significantly differ between the subgroups. Orienting responses are related to risk factors for visual processing impairments known to be prevalent in visual rehabilitation practice. The proposed method may contribute to assessing the effectiveness of visual information processing in children.

Visual function in preterm infants: visualizing the brain to improve prognosis

Considerable development of the visual system occurs in the third trimester of life, a time when very preterm-born infants are in a neonatal intensive care unit (NICU). Their very early birth during a period of rapid and marked neurodevelopment and their clinical course makes them a very high-risk population. A range of different events impacts brain development and the visual system, leading to significant long-term visual dysfunction. Improved neuroimaging techniques provide an important window on the early brain and visual system development of these vulnerable infants. Greater understanding of the etiology of visual impairment subsequent to preterm birth and the timing of critical processes will allow early recognition and the earlier implementations of interventions. In the longer term, this will help clinicians optimize NICU practice to reduce the incidence of visual dysfunction in these children.

Braille use among Norwegian children from 1967 to 2007: trends in the underlying causes

PURPOSE

The aim of the study was to estimate the occurrence, diagnoses and time trends among Norwegian children that have received education in braille from 1967 to 2007.

METHODS

We used a retrospective population-based study design. The health care system is free for all inhabitants in Norway. We included all children that had received braille education the last four decades. From each student's record, we abstracted year born, country of birth, gender, year diagnosed, diagnosis, classification of visual impairment and type of reading media.

RESULTS

We identified 287 children (137 girls and 150 boys) that had received braille education over the last 40 years. Of these, 262 (91.3%) children were born in Norway, 145 (53.7%) were diagnosed within the first year of life and 59 (20.6%) from age of one to five. The most frequent diagnoses were Retinopathy of Prematurity (ROP), Juvenile Ceroid Lipofuscinoses (JNCL), Lebers Congenital Amaurosis (LCA) and Retinitis Pigmentosa (RP). Among the children, 63% (N = 170) used braille only, 9% (N = 25) braille and print, but priority braille, and 27% (N = 73) braille and print, priority print. The number of children with ROP using braille had a peak in 1977, then the number declined. The number diagnosed with LCA increased from 1987 to 1992. The number of braille users among children diagnosed with JNCL tended to increase substantially after 1992.

CONCLUSION

Braille education seemed to be dependent of trends in diagnoses as well as trends in recommendations from professional educators.

Changes in causes of low vision between 1988 and 2009 in a Dutch population of children

PURPOSE

Causes of low vision in the Netherlands may have changed over time. The purpose of this study is to assess trends over the last two decades.

METHODS

Socio-demographic and medical data, including ophthalmic diagnosis and inheritance patterns for 2843 children with low vision (0-21 years; 50% representation) referred to a Dutch institute for low vision (Bartiméus) over a 21-year period between 1988 and 2009, were included in the analysis. For the 19 most common diagnoses, inheritance and presence of mental impairment, trend analyses were performed with logistic regression models; odds ratios (OR) for a 10-year time span were reported.

RESULTS

Cerebral visual impairment (CVI) was found in 27.2% (97% mental impairment), albinism in 8.0%. Over time, nystagmus (6.6%; OR = 1.42), retinitis pigmentosa (2.9%; OR = 1.61), cone-rod dystrophy (2.6%; OR = 1.98) and hyperopia (2.0%; OR = 3.66) increased significantly. Cataract (4.9%; OR = 0.64), aniridia (1.6%; OR = 0.42) and retinopathy of prematurity (ROP; 2.0%; OR = 0.45) decreased significantly. There was a significant increase in genetic disorders (41.0%; OR = 1.49) and in co-occurrence of mental impairment (52.2% OR = 1.16).

CONCLUSION

In the last two decades, treatable or preventable disorders (such as cataract and ROP) have become a less common cause of low vision in children. However, the prevalence of complex (genetic) and untreatable disorders (CVI) has taken its place, as a result of increased survival of preterm and low birth weight children and improved diagnostic possibilities. Knowledge of the prevalence of low vision, its causes and trends over time may help policy makers to define effective intervention strategies and to monitor its impact.

Low vision aids for visually impaired children: a perception-action perspective

It is a widely accepted belief in clinical practice that children with a visual impairment can profit from the use of a low vision aid (LVA). However, we found a considerable gap in our scientific understanding of LVA use, particularly in young children. This is the reason for the analysis presented in this paper. A selected overview of LVA use in adults is given, from which valuable insights are taken. Additionally, an action perspective for analysing LVA use is discussed as well as the results of tool-use studies in children. Mainly based on these three ingredients, we developed a conceptual framework for LVA use. The framework consists of three interacting relations between LVA, child and task. Performance of a particular child on a specific task with a certain LVA is constrained by the following three reciprocal and dynamic relations: the Child-to-Task relation (related to goal-information), the Child-to-LVA relation (related to control-information), and the LVA-to-Task relation (related to topology information).

Childhood visual impairment: normal and abnormal visual function in the context of developmental disability

Abnormal or failed development of vision in children may give rise to varying degrees of visual impairment and disability. Disease and organ-specific mechanisms by which visual impairments arise are presented. The presentation of these mechanisms, along with an explanation of established pathologic processes and correlative up-to-date clinical and social research in the field of pediatrics, ophthalmology, and rehabilitation medicine are discussed. The goal of this article is to enhance the practitioner's recognition and care for children with developmental disability associated with visual impairment.

Brain injury and the eye

Visual loss associated with brain damage is the single greatest cause of visual impairment in children in developed countries. Damage may occur in any of five separate visual systems: primary visual cortex, visual associative cortex area, optic radiations, optic nerves, and visual attention pathways. Improving our understanding of the pathophysiology of these causes for visual loss may lead to better rehabilitation and educational strategies for these children.

Cortical visual impairment: etiology, associated findings, and prognosis in a tertiary care setting

PURPOSE

To evaluate the etiology, prognosis, and associated neurological and ophthalmologic findings of children with cortical visual impairment (CVI) at a tertiary care referral facility.

METHODS

Records from patients visiting the Vanderbilt University Pediatric Ophthalmology Center during 2002 to 2005 were reviewed, and 98 patients were identified with an International Classification of Disease (9th ed.) coding of CVI (377.75). The charts were reviewed to assess presenting symptoms. The clinic and imaging notes were correlated with visual function (graded on a scale of I to VI).

RESULTS

The most common etiologies were perinatal hypoxia (35%), prematurity (29%), hydrocephalus (19%), structural central nervous system abnormalities (11%), and seizures (10%). Many children (69%) had multiple etiologies. Associated ophthalmic abnormalities included esotropia (19%), exotropia (40%), nystagmus (21%), and optic atrophy (42%). Significant refractive error (> +3.00 D or < -2.00 D) was common (20%). Associated neurological findings included seizures (60%), cerebral palsy (37%), periventricular leukomalacia (12%), hemiparesis (21%), and hearing loss (11%). Fifty-three percent of children initially diagnosed with CVI were followed for a period of 0.5 to 10 years. Forty percent of the patients showed no improvement in visual function; 34% had minimal improvement, and 17% had mild improvement. Only 6% of the patients had significant improvement in visual function. Eight patients had fixing and following or better acuity at last follow-up.

CONCLUSIONS

The major risk factors for CVI are perinatal hypoxia, premature birth, and hydrocephalus. Most patients have associated serious neurological and ophthalmologic abnormalities. While many patients have some recovery in vision acuity, most never see well. Patients with the most improvement in visual function were those having better initial acuity.

Visual dysfunctions and ocular disorders in children with developmental delay. I. prevalence, diagnoses and aetiology of visual impairment

PURPOSE

To describe the prevalence, diagnoses and aetiologies of visual impairment in children with developmental delay (DD) in a Danish county with a population of 618 000 citizens.

METHODS

We carried out a cross-sectional study in Copenhagen County of children aged 4-15 years with profound to borderline DD (IQ <or= 80). Children were located through school psychologists or paediatric clinics. The number of children with DD was estimated using the capture-recapture method.

RESULTS

A total of 1126 children fulfilled the inclusion criteria, corresponding to 97.7% of the estimated number of children with DD in the county. Ophthalmological examinations were performed in 923 children. The prevalence of visual impairment was 10.5% in the study group and 22.4% in those with an IQ <or= 50. The diagnoses were predominantly cerebral visual impairment, optic atrophy, retinal dystrophies and congenital nystagmus. The aetiology of visual impairment was prenatal in 54 children, perinatal in 29 children and postnatal in seven children.

CONCLUSIONS

Visual impairment is highly increased in children with DD and is correlated to low IQ.

The key role of electrophysiology in the diagnosis of visually impaired children

PURPOSE

To describe the outcome of specialized electrophysiology in visually impaired children.

METHODS

We carried out a retrospective evaluation of 340 electrophysiological examinations performed in 298 children over a 3-year period (2001-2003), with regard to demographic data, referral pattern, degree of compliance, and diagnostic results. Electrophysiology was performed without sedation or anaesthesia. In electroretinograms, DTL electrodes were used in combination with online selection of responses. Visual evoked potentials testing was performed with seven active occipital electrodes.

RESULTS

The mean age of the children was 7 +/- 5 years; 72 (24%) of the children were mentally as well as visually impaired. Main reasons for referral were suspected posterior segment disease, abnormal visual development, unexplained low vision, high myopia, and suspected albinism. Compliance was good in 302/340 (88%), partial in 24/340 (7%), and absent in 14/340 (4%) of the examinations. Of the 326 successful procedures, 215 (66%) showed abnormal results. Tapetoretinal dystrophy (22%), opticopathy (16%), congenital stationary night blindness (13%), and cone dystrophy (11%) were the most frequently established diagnoses. Albinism was confirmed in 14 of 24 suspected patients; additionally, unsuspected misrouting was found in six. In 26 (9%) of the patients, a previously established diagnosis was changed.

CONCLUSIONS

In a specialized setting, electrophysiological examinations can be performed successfully in visually impaired children. The results are essential for the final ophthalmological diagnosis and have important consequences for rehabilitation.

Correctable and non-correctable visual impairment in a population-based sample of 12-year-old Australian children

PURPOSE

To document the prevalence of correctable and non-correctable visual impairment in a representative sample of Australian children, predominantly age 12 years.

DESIGN

Population-based cross-sectional study.

METHODS

Logarithm of the minimum angle of resolution (logMAR) visual acuity was measured in both eyes unaided, with spectacles if worn, and after subjective refraction if required, in 2353 children, examined during 2004 to 2005. Cycloplegic autorefraction (using cyclopentolate) and dilated fundus examination were performed. Using a cut-off of 0.3 logMAR units (<20/40), presenting visual impairment was defined using unaided visual acuity if spectacles were not worn or with usual correction if spectacles were worn. Impairment not eliminated by refraction was considered non-correctable; any difference between this and presenting impairment was defined as correctable impairment. Myopia was defined as spherical equivalent refraction (SER) < or =-0.50 diopters (D), hyperopia as SER > or =+2.0 diopters, anisometropia as SER difference > or =1.00 diopters, and astigmatism as cylinder > or =1.0 diopters. Amblyopia was defined as corrected visual acuity <0.3 logMAR not attributable to an underlying structural eye or visual pathway abnormality.

RESULTS

Visual impairment was found in the worse eye of 117 children (5.0%) and comprised correctable (82%) and non-correctable impairment (18%). Correctable impairment was due to myopia in 67 (69.8%), hyperopia in 11 (11.5%) and astigmatism in 32 subjects (33.3%). Causes of non-correctable impairment were: amblyopia 66.7%, congenital glaucoma 9.5%, optic nerve hypoplasia 9.5%, congenital nystagmus 4.8%, and cortical blindness 4.8%.

CONCLUSIONS

Visual impairment had a relatively low prevalence in this older childhood population, a large proportion of which was correctable by refraction alone.

Visual acuity and the causes of visual loss in a population-based sample of 6-year-old Australian children

PURPOSE

To describe the distribution of visual acuity and causes of visual loss in a representative sample of Australian schoolchildren.

DESIGN

Population-based cross-sectional study.

PARTICIPANTS

One thousand seven hundred thirty-eight predominantly 6-year old children examined during 2003 to 2004.

METHODS

Logarithm of the minimum angle of resolution (logMAR) visual acuity was measured in both eyes before and after pinhole correction and with spectacles if worn. Cycloplegic autorefraction (cyclopentolate) and detailed dilated fundus examination were performed.

MAIN OUTCOME MEASURES

Visual impairment was defined as any (visual acuity <20/40; <40 letters) or severe (visual acuity < or =20/200; 0-5 letters) for both better and worse eyes. Myopia was defined as spherical equivalent (SE) refraction < or =-0.50 diopters (D), and hyperopia as SE refraction > or =+2.0 D, deemed significant when > or =+3.0 D. Astigmatism was defined as cylinder > or =1.0 D and anisometropia as SE refraction difference between eyes at least 1.0 D. Amblyopia was defined as corrected visual acuity <0.3 logMAR units (<20/40; <40 letters) in the affected eye not attributable to any underlying structural abnormality of the eye or visual pathway, together with a 2-logMAR line difference between the eyes and presence of an amblyogenic risk factor.

RESULTS

The mean visual acuity of this sample was 20/25 (49.3 letters). Uncorrected visual impairment was found in the better eye of 23 children (1.3%) and in the worse eye of 71 children (4.1%). The prevalence was higher in girls than boys and among children of lower socioeconomic status. Refractive error was the most frequent cause, accounting for 69.0%, followed by amblyopia (22.5%). Astigmatism was the principle refractive error causing visual impairment and was frequently uncorrected. Presenting visual impairment (using current glasses if worn) was found in the better and worse eyes of 15 children (0.9%) and 54 children (2.8%), respectively. This was mainly due to under corrected or uncorrected refractive error.

CONCLUSIONS

This study has documented a relatively low prevalence of visual impairment in a population of Australian children. Uncorrected astigmatism and amblyopia were the most frequent causes.

Altered global shape discrimination in deprivation amblyopia

To assess the effect of deprivation amblyopia on global shape discrimination, sensitivity to radial deformation of circular patterns was assessed in patients treated for congenital (N=7) or developmental (N=1) cataracts. Elevation in radial deformation threshold was dependent on circular contour frequency and the depth of amblyopia. Analysis of thresholds expressed as Weber fractions indicated a shift in global integration to a larger scale. In a pedestal experiment, equivalent intrinsic noise increased in proportion to the depth of amblyopia. The results suggest neural undersampling in V1 and/or higher visual cortical areas in deprivation amblyopia and a possible role for neural disarray.

Optic disc morphology may reveal timing of insult in children with periventricular leucomalacia and/or periventricular haemorrhage

AIMS

To evaluate the relation between optic disc morphology and timing of periventricular white matter damage, defined as either periventricular leucomalacia (PVL) or periventricular haemorrhage (PVH), as estimated by neuroradiology.

METHODS

35 children with periventricular white matter damage who had had neuroradiology performed and ocular fundus photographs taken had their photographs analysed by digital image analysis and compared with a control group of 100 healthy full term children. Timing of brain lesion was estimated by analysis of the brain lesion pattern on neuroradiological examinations (magnetic resonance imaging or computed tomography).

RESULTS

Four of 35 children had a small optic disc area; these four children had a brain lesion estimated to have occurred before 28 weeks of gestation. Nine of 11 children with a large cup area had a PVL/PVH estimated to have occurred after 28 weeks of gestation. The children with PVL/PVH had a significantly larger cup area (median 0.75 mm(2)) than the control group (median 0.33 mm(2)) (p = 0.001) and a significantly smaller neuroretinal rim area (median 1.58 mm(2)) than the controls (median 2.07 mm(2)) (p = 0.001).

CONCLUSION

In a child with PVL/PVH and abnormal optic disc morphology, the possibilities of timing of the lesion should be considered.

Causes of blindness at the "Wiyata Guna" School for the Blind, Indonesia

AIM

To determine the anatomical site and patterns of cause of blindness in one of the biggest schools for the blind in Indonesia with a view to determining potentially preventable and treatable causes.

METHODS

165 students in one school for the blind in Bandung, Indonesia, were examined clinically and data reported using the WHO/PBL childhood blindness assessment form.

RESULTS

Most of the students (96.4%) were blind (BL); 3% were severely visually impaired (SVI). The major causes of SVI/BL in this study were: (1) corneal staphyloma, corneal scar, and phthisis bulbi (mainly attributed to infection) in 29.7%; (2) retinal dystrophies (mainly Leber congenital amaurosis, early onset retinitis pigmentosa) in 20.6%; (3) congenital and familial cataract (13.3%); (4) microphthalmus, anophthalmus (10.9%). The whole globe was the major anatomical site of visual loss (32.7%), followed by the retina (26.0%), cornea (17.6%), lens (13.3%), optic nerve (6.1%), and uvea (4.3%).

CONCLUSIONS

This is a small study in a selected population and the results should be interpreted with caution. This blind school study, adopting the WHO/PBL eye form for data analysing, is the first reported for Indonesia. Hereditary disease and infective causes of blindness are the predominant causes of blindness, accounting for 42.4% and 29.7%, respectively. This pattern of causes is a mixed pattern which lies in an intermediate position between the patterns seen in developing countries and those seen in developed countries. The importance both of preventive public health strategies and of specialist paediatric ophthalmic and optical services in the management of childhood blindness in Indonesia are therefore strongly suggested to cover the problems that exist.

Visual function in the brain-damaged child

The essential role of the primary visual cortex in visual processing has been extensively studied over the last century or more. Injuries to the visual cortex in adult humans can produce blindness, referred to as "cortical blindness". In children some degree of visual recovery has been noted in comparable injuries and for that reason the term "cortical visual impairment" has been suggested as a more appropriate diagnosis in children. This term is, however, inaccurate as a significant number of children with visual loss and neurologic damage have injuries to the noncerebral pathways (for example--optic radiations in children with periventricular leukomalacia). In this study we compare visual outcomes and recovery in children with primary visual cortex lesions vs those with periventricular leukomalacia. We suggest that the poorer outcomes of children with periventricular leukomalacia could have been predicted based on studies of the mechanisms of visual recovery in infant animals following visual cortex ablation.

A survey of visual impairment in children attending the Royal Blind School, Edinburgh using the WHO childhood visual impairment database

PURPOSE

To assess the aetiology and changing patterns of childhood blindness in one school for the blind in the UK and to assess the use of the World Health Organisation Prevention of Blindness (WHO/PBL) methodology and reporting form in a developed country.

METHODS

One hundred and seven children in one school for the blind and visually impaired in Edinburgh were examined using the WHO/PBL childhood blindness assessment form.

RESULTS

Of the 107 children examined, 87 (81%) were blind or severely visually impaired (corrected visual acuity of <6/60 (20/200) in the better eye). Perinatal related blindness (40%), hereditary disease (26%) and developmental factors (26%) formed the three largest aetiological categories.

CONCLUSION

The pattern of childhood blindness seen in this study was similar to reports from other developed countries. The WHO/PBL reporting form allows detailed comparisons between countries and over time. Additional fields for more detailed reporting of cerebral visual impairment and associated handicaps would increase the usefulness of the WHO/PBL form for population-based studies and for use in developed countries.

Visual impairment and blindness in Europe and their prevention

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

Causes of severe visual impairment and blindness in children attending schools for the visually handicapped in the Czech Republic

AIMS

To describe the causes of severe visual impairment and blindness in children in schools for the visually handicapped in the Czech Republic in 1998.

METHODS

Pupils attending all 10 primary schools for the visually handicapped were examined. A modified WHO/PBL eye examination record for children with blindness and low vision was used.

RESULTS

229 children (146 males and 83 females) aged 6-15 years were included in the study: 47 children had severe visual impairment (20.5%) (visual acuity in their better eye less than 6/60), and 159 were blind (69.5%) (visual acuity in their better eye less than 3/60). Anatomically, the most affected parts of the eye were the retina (124, 54.2%), optic nerve (35, 15.3%), whole globe (25, 10.9%), lens (20, 8.7%), and uvea (12, 5.2%). Aetiologically (timing of insult leading to visual loss), the major cause of visual impairment was retinopathy of prematurity (ROP) (96, 41.9 %), followed by abnormalities of unknown timing of insult (97, 42.4%), and hereditary disease (21, 9.2%). In 90 children (40%), additional disabilities were present: mental disability (36, 16%), physical handicap (16, 7%), and/or a combination of both (19, 8%). It was estimated that 127 children (56%) suffer from visual impairment caused by potentially preventable and/or treatable conditions (for example, ROP, cataract, glaucoma).

CONCLUSIONS

Establishing a study group for comprehensive evaluation of causes of visual handicap in children in the Czech Republic, as well as for detailed analysis of present practice of screening for ROP was recommended.