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Background/aimsUnderstanding temporal trends in childhood visual disability is necessary for planning and evaluating clinical services and health policies. We investigate the changing epidemiology of severe visual impairment (SVI) and blindness (BL) in children in the UK in the 21st century.MethodsComparative analysis of two national population-based epidemiological studies of incident childhood SVI/BL (ICD-10 definition; visual acuity worse than 1.0 LogMAR in the better eye). We carry out comparative analysis of studies conducted in 2000 and 2015 using identical methods.ResultsOverall annual and cumulative incidence rates remained broadly stable in 2015 at 0.38 per 10 000 (95% CI 0.34 to 0.41) for 0–15 years old and 5.65 per 10 000 (5.16 to 6.18) by 16 years, respectively, and with annual incidence in infancy (3.52 per 10 000, 3.13 to 3.97) remaining considerably higher than any other age. Mortality among children diagnosed in infancy declined (from 61.4 to 25.6 per 1000), despite an increase (from 77% to 84%, p=0.037) in the overall proportion with significant non-ophthalmic impairments/disorders. The relative contribution of all the main groups of disorders increased over time, most notably cerebral visual impairment (from 50% to 61%). Aetiological factors operating prenatally continued to predominate, with an increased relative contribution of hereditary conditions in all children (from 35% to 57%, pConclusionThe changing landscape of healthcare and increased survival of affected children, is reflected in increasing clinical complexity and heterogeneity of all-cause SVI/BL alongside declining mortality.

Background/aimsEvaluation of telemedicine care models has highlighted its potential for exacerbating healthcare inequalities. This study seeks to identify and characterise factors associated with non-attendance across face-to-face and telemedicine outpatient appointments.MethodsA retrospective cohort study at a tertiary-level ophthalmic institution in the UK, between 1 January 2019 and 31 October 2021. Logistic regression modelled non-attendance against sociodemographic, clinical and operational exposure variables for all new patient registrations across five delivery modes: asynchronous, synchronous telephone, synchronous audiovisual and face to face prior to the pandemic and face to face during the pandemic.ResultsA total of 85 924 patients (median age 55 years, 54.4% female) were newly registered. Non-attendance differed significantly by delivery mode: (9.0% face to face prepandemic, 10.5% face to face during the pandemic, 11.7% asynchronous and 7.8%, synchronous during pandemic). Male sex, greater levels of deprivation, a previously cancelled appointment and not self-reporting ethnicity were strongly associated with non-attendance across all delivery modes. Individuals identifying as black ethnicity had worse attendance in synchronous audiovisual clinics (adjusted OR 4.24, 95% CI 1.59 to 11.28) but not asynchronous. Those not self-reporting their ethnicity were from more deprived backgrounds, had worse broadband access and had significantly higher non-attendance across all modes (all pConclusionPersistent non-attendance among underserved populations attending telemedicine appointments highlights the challenge digital transformation faces for reducing healthcare inequalities. Implementation of new programmes should be accompanied by investigation into the differential health outcomes of vulnerable populations.

BackgroundPatient-reported outcome measures (PROMs) are increasingly used in paediatric ophthalmology. However, little is known about the distribution of PROM scores among children and young people with visual impairment.AimTo investigate the distributions and predictors of scores on the VQoL_CYP (measuring vision-related quality of life) and FVQ_CYP (measuring functional vision).MethodsChildren and young people aged 8–18 years, with visual impairment/blindness (logarithm of the minimum angle of resolution (LogMAR) worse than 0.48 in the better eye, and/or eligible visual field restriction) completed the VQoL_CYP and FVQ_CYP at home or Great Ormond Street Hospital, London, UK. Associations between VQoL_CYP and FVQ_CYP scores and sociodemographic and clinical factors were analysed using multiple linear regression models.ResultsAmong 93 participants, VQoL_CYP scores ranged from 36.6 to 78.2 (mean=57.9, SD=8.1). FVQ_CYP scores ranged from 23.5 to 70.3 (mean=48.3, SD=10.1). Only 0.4% of the variation in VQoL_CYP scores was explained, with no associations with the variables of interest. By contrast, 21.6% of the variation in FVQ_CYP scores was explained, with a gradient of worse acuity (pDiscussionSelf-rated vision-related quality of life and functional vision are not readily predicted from sociodemographic or clinical characteristics that ophthalmologists measure/record. Routine use of PROMs in clinical practice can offer important insights. Use in research can provide valuable measures of effectiveness of interventions. The reference values provided will aid interpretation in both settings.

Background/aimsAddressing childhood visual disability is an international priority, with data on causes needed to plan, implement and evaluate public health and clinical care. We have examined the contribution of ‘avoidable’ blinding disorders to childhood visual impairment, severe visual impairment and blindness (VI/SVIBL) in the UK.MethodsNational prospective observational longitudinal study, the British Childhood Visual Impairment and Blindness Study 2 (BCVIS2), of children (aged 18 years or under) newly diagnosed with vision worse than 0.48 logMAR (logarithm of the minimum angle of resolution) or equivalent in both eyes. Proportions of children with an ‘avoidable’ disorder comprising either apotentially preventable(isolated disorders with an effective intervention which reduces disease incidence) ortreatable(isolated eye or vision disorders for which there are routinely available effective interventions able to improve vision or halt progressive visual loss) are reported.ResultsOf the 784 children within BCVIS2, isolated potentially preventable disorders were present in only 17% (132/784) and treatable disorders in an additional 13% (99/784). The most common treatable causes were cataract, retinopathy of prematurity and glaucoma. Of the 132 children with potentially preventable disease, 64 had hypoxic–ischaemic encephalopathy. Non-accidental injury accounted for almost two-thirds (11/16, 69%) of those with VI/SVIBL due to injury.ConclusionDespite significant progress in the past decades in high-income countries, there remains a need to be vigilant about implementing preventive strategies and treatments. Attention to disorders that are currently neither preventable nor treatable remains a priority in these settings and will become increasingly important in lower-income and middle-income countries undergoing economic transition.

Background/aimsThere is a paucity of high-level evidence to support the management of childhood uveitis, particularly for those children without juvenile idiopathic arthritis uveitis (JIA). We undertook a modified Delphi consensus exercise to identify agreement in the management of chronic anterior uveitis (CAU), the most common manifestation of childhood disease.MethodsA four-round, two-panel process was undertaken between June and December 2017. Paediatric uveitis specialists identified through multiple sources, including a multicentre network (the Paediatric Ocular Inflammation Group), were invited to participate. They were asked whether they agreed with items derived from existing guidelines on the management of JIA-U when extrapolated to the population of all children with CAU. Consensus was defined as agreement greater than or equal to 75% of respondents.Results26 of the 38 (68%) invited specialists participated with the exercise, and response rates were 100% for rounds one to three, and 92% for round four. Consensus was reached on 23 of the 44 items. Items for which consensus was not reached included management at presentation, use of systemic and periocular steroids for children with severe disease and the role of conventional steroid sparing immunosuppressants beyond methotrexate.ConclusionThe areas of management uncertainty at the level of the group, as indicated by absence of consensus, reflect the areas where the evidence base is particularly poor. Our findings identify the key areas for the future research needed to ensure better outcomes for this blinding childhood ocular inflammatory disorders.

Background/aimsAnterior segment optical coherence tomography (AS-OCT) assessment of anterior chamber inflammation is an emerging tool. We describe the performance of AS-OCT in a paediatric population.MethodsA mixed-methods prospective study, using routine clinical assessment as reference standard, and AS-OCT, with Tomey CASIA2 or Heidelberg Spectralis HS1, as index test, with data collected on patient perceptions of imaging. Repeatability, diagnostic indices, responsiveness to clinical change and clinical correlations of imaging-based metrics (image cell count, size, density and brightness) were assessed, with construction of receiver operated characteristic curves. Exploratory thematic analysis of responses from families was undertaken.ResultsA total of 90 children (180 eyes) underwent imaging. Bland Altman limits of agreement for CASIA2 repeatability ranged from +17 cells (95% CI 13.6 to 21.1) to −19 cells (95% CI −15.6 to −23.2) and HS1 from +1 (95% CI 0.9 to 1.2) to −1.0 (−1.2 to −0.8) cells. CASIA2 imaging had higher sensitivity of 0.92 (95% CI 0.78 to 0.97) vs HS1 imaging 0.17 (95% CI 0.07 to 0.34), with positive correlation between clinical grade and CASIA2 cell count (coefficient 12.8, p=0.02, 95% CI 2.2 to 23.4). Change in clinical grade at follow-up examinations correlated with change in image based ‘cell’ count (r2=0.79, pConclusionOur findings suggest that OCT-based imaging holds the promise of deeper understanding of disease, improved patient experience and more granular monitoring of activity with resultant improved outcomes, but further work is needed to refine acquisition and analysis protocols.

AimsWe compared feasibility, quality and outcomes of visual field (VF) testing in children with neuro-ophthalmic disease between the discontinued ‘gold-standard’ Goldmann and Octopus perimeters.MethodsChildren with neuro-ophthalmic disease, attending Great Ormond Street Hospital, London, were assessed using standardised protocols by one examiner in a single sitting, using Goldmann and Octopus kinetic perimetry. Outputs were classified to compare severity of loss and defect type. Test quality was assessed using both qualitative and quantitative methods.ResultsThirty children (40% female) aged 5–15 years participated. Goldmann perimetry was completed in full by 90.0% vs 72.4% for Octopus. Inability to plot the blind spot was the most common reason for not completing testing. Over 75% completed a test in ≤20 min. Duration was similar between perimeters (paired t-test, mean difference: 0.48min (−1.2, 2.2), p=0.559). The lowest quality tests were for Octopus perimetry in children 2=1.0, p=0.317). There was broad agreement between Goldmann and Octopus outputs (good quality, n=21, Bland-Altman, mean difference for isopters I4e (−514.3 deg2(−817.4, –211.2), p=0.814), I2e (−575.5 deg2(−900.1, –250.9), p=0.450) and blind spot (20.8 deg2(5.7, 35.8), p=0.451)). However, VF severity grades and defect type matched in only 57% and 69% of tests, respectively. Octopus perimetry underestimated severe VF defects.ConclusionsInformative perimetry is feasible in children ≥8 years with neuro-ophthalmic conditions, with either Goldmann or Octopus perimeters. However, meaningful differences exist between the two approaches with implications for consistency in longitudinal assessments.

BackgroundRefractive error is an increasing global public health concern that requires robust and reliable research to identify modifiable risk factors and provide accurate estimates of population burden. We investigated the impact of reclassification of individuals when using different threshold values of spherical equivalent (SE) to define myopia, on estimates of frequency, distribution and associations with risk factors, to inform current international initiatives to standardise definitions.MethodsA random sample of 1985 individuals from the 1958 British birth cohort, at age 44, had autorefraction and self-reported on educational attainment and social class.Refraction status assigned in three different models using SE: (A) moderate to high myopia −3 diopters (D) or more extreme (≤−3.00D), (B) hypermetropia +1.00D or more extreme (≥+1.00D) and (C) mild myopia using three different thresholds: −1.00D, −0.75D or −0.50D, hence reciprocal changes in definition of emmetropia.ResultsFrequency estimates and associations with risk factors altered significantly as the threshold value for myopia moved towards SE 0.0D: prevalence of mild myopia increased from 28% to 47%, the association with highest educational attainment attenuated and with higher social class strengthened, with changes in risk ratios of approximately 20%.ConclusionEven small changes in the threshold definition of myopia (±0.25D) can significantly affect the conclusions of epidemiological studies, creating both false-positive and false-negative associations for specific risk factors. An international classification for refractive error, empirically evidenced and cognisant of the question(s) being addressed and the population(s) being studied, is needed to serve better translational research, practice and policy.

Introduction Interpretation of perimetric findings, particularly in children, relies on accurate assessment of test reliability, yet no objective measures of reliability exist for kinetic perimetry. We developed the kinetic perimetry reliability measure (KPRM), a quantitative measure of perimetric test reproducibility/reliability and report here its feasibility and association with subjective assessment of reliability. Methods Children aged 5–15 years, without an ophthalmic condition that affects the visual field, were recruited from Moorfields Eye Hospital and underwent Goldmann perimetry as part of a wider research programme on perimetry in children. Subjects were tested with two isopters and the blind spot was plotted, followed by a KPRM. Test reliability was also scored qualitatively using our examiner-based assessment of reliability (EBAR) scoring system, which standardises the conventional clinical approach to assessing test quality. The relationship between KPRM and EBAR was examined to explore the use of KPRM in assessing reliability of kinetic fields. Results A total of 103 children (median age 8.9 years; IQR: 7.1 to 11.8 years) underwent Goldmann perimetry with KPRM and EBAR scoring. A KPRM was achieved by all children. KPRM values increased with reducing test quality (Kruskal-Wallis, p=0.005), indicating greater test-retest variability, and reduced with age (linear regression, p=0.015). One of 103 children (0.97%) demonstrated discordance between EBAR and KPRM. Conclusion KPRM and EBAR are distinct but complementary approaches. Though scores show excellent agreement, KPRM is able to quantify within-test variability, providing data not captured by subjective assessment. Thus, we suggest combining KPRM with EBAR to aid interpretation of kinetic perimetry test reliability in children.

Background/aims To investigate outcomes following cataract surgery with and without primary intraocular lens (IoL) implantation in children under 2 years of age with congenital or infantile cataract. Method Prospective population based cohort study undertaken through the British Isles Congenital Cataract Interest Group, with systematic data collection on children undergoing surgery in UK and Ireland between January 2009 and December 2010. ORs for the association between IoL implantation and visual acuity, postoperative glaucoma and reoperation at 1 year after surgery were estimated using multivariable regression analysis to control for potential confounders. Results Of 221 children, 56/131 with bilateral and 48/ 90 with unilateral cataract underwent primary IoL implantation. IoL implantation was independently associated with better visual outcome in bilateral (OR 4.6, 95% CI 1.6 to 13.1, p=0.004) but not unilateral disease. IoL use increased the odds of reoperation requiring repeat general anaesthetic (bilateral OR 5.5, p

Aims/Background: Population-based information is useful for future strategic planning of healthcare resources. We wished to describe and cost the provision of eye services, beyond those of basic primary and emergency care, for the paediatric population of a single Primary Care Trust. Methods: Data from healthcare purchaser and provider records were collected for the year 2004/5 on provision and costing of hospital eye services, provision of spectacle vouchers, orthoptic screening, social services and visual impairment team services to children in the Huntingdon PCT population. Results: In the year of study, in a population of 33,564 aged under 18 years, 1870 (5.6%) children underwent screening by an orthoptist. 1970 (5.9%) children required outpatient appointments, 445 (1.3%) were prescribed spectacles, and 87 (0.3%) children needed surgical procedures. A small proportion (69, 0.2%) of children were visually impaired. The total cost of providing comprehensive eye services to children within Hunts PCT was £366,727. Conclusion: Although the prevalence of significant visual impairment is low in childhood, overall, eye conditions are common in children and may have lifelong implications. The resources required to provide a comprehensive paediatric eye service, to screen for and manage common eye conditions, and support those with serious eye conditions or visual impairment, are significant. This study aids quantified prediction of future service usage, and facilitates decision-making on resource allocation and workforce organisation for children9s eye care in the UK.

Background: Detection and treatment of undiagnosed refractive error (RE), with its attendant functional consequences, is a priority of VISION 2020, the global initiative against avoidable visual disability. The authors investigated the frequency of visual impairment due to undiagnosed RE and its associations with vision-related quality of life (VRQOL), general health and social circumstances in a contemporary and nationally representative population of British working-age adults. Methods: 9271 members of the 1958 British birth cohort had visual acuity and VRQOL assessed at 44/45 years. The authors compared those with undiagnosed RE with those with diagnosed RE, defining undiagnosed RE as ⩾0.2 logMAR units/2 lines acuity improvement in both eyes with pinhole in individuals without current or prior optical treatment or ophthalmic history. Results: 144/9271 (1.6%) individuals had undiagnosed and 3513/9271 (37.9%) diagnosed RE. 18% (24/144) of those with undiagnosed RE were classifiable as visually impaired. Individuals with undiagnosed RE were more likely to have a manual (vs non-manual) occupation and to be separated, divorced or widowed, and less likely to be in social or professional organisations. There is also some evidence that they are more likely to express concern, embarrassment and frustration about their eyesight and worry about coping with life. Conclusion: A significant proportion of working age adults in Britain appear to have undiagnosed but visually significant RE. Improvements in existing opportunities for detecting RE in adults could benefit these individuals during their working lives and avoid the serious adverse consequences associated with vision impairment in later life.

Aim: To investigate the health service experiences and needs of parents in the period around diagnosis of ophthalmic disorders in their children. Methods: Parents of children newly diagnosed with visual impairment and/or ophthalmic disorders at a tertiary level hospital in London participated in a questionnaire survey, using standard instruments, followed by in-depth individual interviews, to elicit their views about the processes of care, their overall level of satisfaction, and their unmet needs. Results: 67% (147) of eligible families (135 mothers, 76 fathers) participated. Overall satisfaction with care was high, being greater among parents of children with milder visual loss or isolated ophthalmic disorders than those with more severe visual loss or multiple impairments. Nevertheless, parents’ reported greatest need was the provision of general information, including about their child’s ophthalmic disorder and educational and social services and support. Mothers reported greater information needs than fathers, as did white parents compared to those from ethnic minorities. White parents also regarded the processes of care to be less comprehensive and coordinated, as well as less enabling, than did parents from ethnic minorities. Conclusions: Although parents reported high overall satisfaction with services, improving the medium, content, and scope of general information provided by professionals to parents of visually impaired children emerges as a priority. Equitable planning and provision of health services for families of children with visual impairment needs to take into account that informational and other needs vary by whether the parent is the primary carer or not and their ethnicity, as well as by the severity and complexity of their child’s visual loss.

Aims: To estimate the risk of aphakic glaucoma after lensectomy for congenital cataract and its association with surgery within the first month of life. Method: A retrospective case notes review was conducted of all patients who had lensectomy for congenital cataract during their first year of life at Great Ormond Street Hospital between 1994 and 1997. Patients with pre-existing glaucoma, anterior segment dysgenesis, and Lowe syndrome were excluded. The risk of aphakic glaucoma after surgery was estimated using Kaplan-Meier survival analysis. Results: 80 patients, undergoing 128 lensectomies were eligible. Of these, six patients (nine eyes) were lost to follow up. Based on eye count, the risk of glaucoma by 5 years after lensectomy was 15.6% (95% CI 10.2 to 23.4). Based on patient count, the 5 year risk of glaucoma in at least one eye following bilateral surgery was 25.1% (95% CI 15.1 to 40.0). The incidence of glaucoma remained at a constant level for the first 5 years after surgery. After early bilateral lensectomy, within the first month of life, the 5 year risk of glaucoma in at least one eye was 50% (95% CI 27.8 to 77.1) compared to 14.9% (95% CI 6.5 to 32.1) with surgery performed later (log rank test, p = 0.012). There was no significant difference (Kolmogorov-Smirnov test: unilateral lensectomy p = 0.587, bilateral lensectomy p = 0.369) in 5 year visual outcomes between eyes operated before and after 1 month of age. Conclusion: Bilateral lensectomy during the first month of life is associated with a higher risk of subsequent glaucoma than with surgery performed later. The reason for this is unclear but it may be prudent, in bilateral cases, to consider delaying surgery until the infant is 4 weeks old. As the incidence of glaucoma is similar for each year after surgery, long term glaucoma surveillance is mandatory.

Aims:\ud To investigate agreement between children with visual impairment (VI) and their parents on their ratings of the child's vision-related quality of life (VQoL) and functional vision (FV) using two novel self-report patient-reported outcome measures developed for this population.\ud \ud Methods:\ud 99 children aged 10–15 years (mean age=12.2, SD=1.9) with VI (best corrected acuity (logarithm of the minimum angle of resolution) 0.50 or worse in better eye) and their parents participated in a national postal survey, completing the child and proxy versions of our novel instruments assessing VQoL and FV of children with VI—the vision-related quality of life instrument for children and young people (VQoL_CYP) and the functional vision questionnaire for children and young people (FVQ_CYP), respectively. Parent-child agreement was investigated using the Bland-Altman (BA) method. Variation across key sociodemographic and clinical characteristics was examined using the Intraclass Correlation Coefficient.\ud \ud Results:\ud Average parental ratings of their child's VQoL and FV were significantly lower than the children's own ratings, but the range of disagreement was wide, with parents both overestimating and underestimating their child's VQoL (mean score difference=5.7, BA limits of agreement (LOA): lower −22.10 (CI 95% −24.61 to 19.59) and upper 33.50 (CI 95% 30.99 to 36.01)), but more consistently underestimating the child's FV (mean score difference=−11.8, BA LOA: lower −39.60 (CI 95% −42.12 to 37.08) and upper 16 (CI 95% 13.48 to 18.52)). There was variation in agreement by some child characteristics, including vision level, time of onset and course of VI progression.\ud \ud Conclusions:\ud Visually impaired children and their parents perceive the broader impact of living with VI very differently. There is value in routine capture of information independently from children and their parents for comprehensively gauging the impact of childhood VI and tailoring appropriate interventions.

BACKGROUND/AIMS Congenital ocular anomalies contribute significantly to childhood visual morbidity, with congenital cataract being a major cause of visual impairment throughout the world. As in many other countries, a National Congenital Anomaly System (NCAS) exists in England and Wales to monitor the frequency of ocular and other anomalies in order to identify new public health hazards and inform aetiological research. The aim of this study was to assess level of ascertainment by the NCAS of children with congenital cataract. METHODS Using independent ophthalmic and paediatric national active surveillance schemes, all infants (⩽1 year) newly diagnosed with congenital and infantile cataract in England and Wales in 1 year from September 1995 were identified. These notifications were compared with those made independently to the NCAS during the same period. The proportion of cases identified by the active surveillance schemes and also notified to the NCAS was determined. RESULTS 10% (15/149) of eligible children with newly diagnosed congenital or infantile cataract were actually notified to the NCAS. A higher proportion of those diagnosed as neonates (16%, 14/85) than in later infancy (2%, 1/64) was ascertained through the NCAS. There is a need for better verification of notifications and reported information in the NCAS. CONCLUSION Currently, ascertainment of congenital cataract through the NCAS is low and the system is likely to be insensitive to small but important changes in risk factors for this disorder. This limits its use for monitoring secular and other trends in ocular anomalies. Strategies to improve its future use are discussed, including enhancing the awareness and participation of ophthalmic professionals involved in managing children with anomalies.

AIMS To determine the visual outcome and complications of lens aspiration with intraocular lens implantation in children aged 5 years and under. METHODS The hospital notes of all children aged 5 years and under, who had undergone lens aspiration with intraocular lens implantation between January 1994 and September 1998, and for whom follow up data of at least 1 year were available, were reviewed. RESULTS Of 50 children who underwent surgery, 45 were eligible based on the follow up criteria. 34 children had bilateral cataracts and, of these, 30 had surgery on both eyes. Cataract was unilateral in 11 cases; thus, 75 eyes of 45 children had surgery. Cataracts were congenital in 28 cases, juvenile in 16, and traumatic in one case. The median age at surgery was 39 months (range 11–70 months). Follow up ranged from 12–64 months (median 36 months). Of 34 children with bilateral disease, 25 (73.5%) had a final best corrected visual acuity of 6/12 or better, while seven (20.5%) achieved 6/18 or less; in one child the vision improved from UCUSUM to CSM but another, who had only one eye operated on, was unable to fix or follow with this eye preoperatively or 2 years postoperatively. Of 11 children with unilateral cataract, five (45.5%) had a final best corrected visual of 6/12 or better, and six (54.5%) 6/18 or less. A mild fibrinous uveitis occurred in 20 (28.2%) eyes in the immediate postoperative period, but resolved with topical steroids. One child had a vitreous wick postoperatively requiring surgical division. Glaucoma, endophthalmitis, or retinal detachment have not been observed so far in any patient postoperatively. CONCLUSION From this series the authors suggest that, in children aged 5 years and under, lens aspiration with intraocular lens implantation is a safe procedure, with a good visual outcome in the short term. Further studies are needed to investigate these outcomes in the long term.

Established in Britain in the 19th century, the sight impairment register has been the sole means of routinely monitoring the frequency and causes of visual impairment in children to plan services and prioritise research.1 Although not a prerequisite, certification and consequent registration is often the catalyst for statutory assessment of special educational needs. It is also often the portal for accessing social services.2 Certification remains voluntary in the UK, by contrast with similar registers elsewhere. However, considerable effort has recently been directed to addressing previous concerns about incomplete reporting of information and underascertainment of eligible individuals.1 2 We have previously reported incidence and causes of severe visual impairment (SVI) or blindness (BL) and associated mortality3 in a nationally representative group of children with SVI/BL in the UK. We now report on the BL certification status of these children 1 year after diagnosis. Active surveillance was undertaken, simultaneously but independently, through the British Ophthalmological4 and British Paediatric5 Surveillance Units, whose reporting bases comprise all consultant ophthalmologists and paediatricians, respectively, in the UK. Every month for 1 year (2000), clinicians reported all children aged