Neuroradiographic, endocrinologic, and ophthalmic correlates of adverse developmental outcomes in children with optic nerve hypoplasia: a prospective study

Position statement on the diagnosis and management of congenital pituitary deficiency in adults: The French National Diagnosis and Treatment Protocol (NDTP)

Pituitary deficiency, or hypopituitarism, is a rare chronic disease. It is defined by insufficient synthesis of one or more pituitary hormones (growth hormone, TSH, ACTH, LH-FSH, prolactin), whether or not associated with arginine vasopressin deficiency (formerly known as diabetes insipidus). In adult patients, it is usually acquired (notably during childhood), but can also be congenital, due to abnormal pituitary development. The present study focuses on congenital pituitary deficiency in adults, from diagnosis to follow-up, including special situations such as pregnancy or the elderly. The clinical presentation is highly variable, ranging from isolated deficit to multiple deficits, which may be part of a syndromic form or not. Diagnosis is based on a combination of clinical, biological (assessment of all hormonal axes), radiological (brain and hypothalamic-pituitary MRI) and genetic factors. Treatment consists in hormonal replacement therapy, adapted according to the period of life and the deficits, which may be progressive. Comorbidities, risk of complications and acute decompensation, and the impact on fertility and quality of life all require adaptative multidisciplinary care and long-term monitoring.

Diagnosis and management of congenital hypopituitarism in children

Hypopituitarism (or pituitary deficiency) is a rare disease with an estimated prevalence of between 1/16,000 and 1/26,000 individuals, defined by insufficient production of one or several anterior pituitary hormones (growth hormone [GH], thyroid-stimulating hormone [TSH], adrenocorticotropic hormone [ACTH], luteinizing hormone [LH], follicle-stimulating hormone [FSH], prolactin), in association or not with diabetes insipidus (antidiuretic hormone [ADH] deficiency). While in adults hypopituitarism is mostly an acquired disease (tumors, irradiation), in children it is most often a congenital condition, due to abnormal pituitary development. Clinical symptoms vary considerably from isolated to combined deficiencies and between syndromic and non-syndromic forms. Early signs are non-specific but should not be overlooked. Diagnosis is based on a combination of clinical, laboratory (testing of all hormonal axes), imaging (brain magnetic resonance imaging [MRI] with thin slices centered on the hypothalamic-pituitary region), and genetic (next-generation sequencing of genes involved in pituitary development, array-based comparative genomic hybridization, and/or genomic analysis) findings. Early brain MRI is crucial in neonates or in cases of severe hormone deficiency for differential diagnosis and to inform syndrome workup. This article presents recommendations for hormone replacement therapy for each of the respective deficient axes. Lifelong follow-up with an endocrinologist is required, including in adulthood, with multidisciplinary management for patients with syndromic forms or comorbidities. Treatment objectives include alleviating symptoms, preventing comorbidities and acute complications, and optimal social and educational integration.

Aberrant gene expression yet undiminished retinal ganglion cell genesis in iPSC-derived models of optic nerve hypoplasia

BACKGROUND

Optic nerve hypoplasia (ONH), the leading congenital cause of permanent blindness, is characterized by a retinal ganglion cell (RGC) deficit at birth. Multifactorial developmental events are hypothesized to underlie ONH and its frequently associated neurologic and endocrine abnormalities; however, environmental influences are unclear and genetic underpinnings are unexplored. This work investigates the genetic contribution to ONH RGC production and gene expression using patient induced pluripotent stem cell (iPSC)-derived retinal organoids (ROs).

MATERIALS AND METHODS

iPSCs produced from ONH patients and controls were differentiated to ROs. RGC genesis was assessed using immunofluorescence and flow cytometry. Flow-sorted BRN3+ cells were collected for RNA extraction for RNA-Sequencing. Differential gene expression was assessed using DESeq2 and edgeR. PANTHER was employed to identify statistically over-represented ontologies among the differentially expressed genes (DEGs). DEGs of high interest to ONH were distinguished by assessing function, mutational constraint, and prior identification in ONH, autism and neurodevelopmental disorder (NDD) studies.

RESULTS

RGC genesis and survival were similar in ONH and control ROs. Differential expression of 70 genes was identified in both DESeq2 and edgeR analyses, representing a ~ 4-fold higher percentage of DEGs than in randomized study participants. DEGs showed trends towards over-representation of validated NDD genes and ONH exome variant genes. Among the DEGs, RAPGEF4 and DMD had the greatest number of disease-relevant features.

CONCLUSIONS

ONH genetic background was not associated with impaired RGC genesis but was associated with DEGs exhibiting disease contribution potential. This constitutes some of the first evidence of a genetic contribution to ONH.

Neurodevelopmental impairments in children with septo-optic dysplasia spectrum conditions: a systematic review

BACKGROUND

Septo-optic dysplasia (SOD) is a rare condition diagnosed in children with two or more of the following: hypopituitarism, midline brain abnormalities, and optic nerve hypoplasia. Children with SOD experience varied visual impairment and endocrine dysfunction. Autistic-like behaviours have been reported; however, their nature and prevalence remain to be fully understood. The present systematic review aimed to explore the type and prevalence of neurodevelopmental impairments in children with SOD spectrum conditions.

METHODS

The search was conducted in PubMed, EMBASE, and PsycInfo. Hand-searching reference lists of included studies was conducted. All peer-reviewed, observational studies assessing behavioural and cognitive impairments or autism spectrum disorder (ASD) symptoms in children (< 18 years) with SOD, optic nerve hypoplasia, and SOD-plus were included. Studies were excluded if they did not report standardised measures of neurodevelopmental impairments or ASD outcomes.

RESULTS

From 2132 screened articles, 20 articles reporting data from a total of 479 children were included in prevalence estimates. Of 14 studies assessing cognitive-developmental outcomes, 175 of 336 (52%) children presented with intellectual disability or developmental delay. A diagnosis of ASD or clinical level of symptoms was observed in 65 of 187 (35%) children across five studies. Only five studies assessed for dysfunction across behavioural, emotional, or social domains and reported impairments in 88 of 184 (48%) of children assessed.

LIMITATIONS

Importantly, high heterogeneity among the samples in relation to their neuroanatomical, endocrine, and optic nerve involvement meant that it was not possible to statistically assess the relative contribution of these confounding factors to the specific neurodevelopmental phenotype. This was further limited by the variation in study designs and behavioural assessments used across the included studies, which may have increased the risk of information bias.

CONCLUSIONS

This systematic review suggests that the prevalence of neurodevelopmental impairments in children within the SOD spectrum may be high. Clinicians should therefore consider including formal assessments of ASD symptoms and neurodevelopmental impairments alongside routine care. There is, additionally, a need for further research to define and validate a standardised battery of tools that accurately identify neurodevelopmental impairments in SOD spectrum conditions, and for research to identify the likely causal mechanisms.

Association of prepregnancy body mass index and gestational weight gain on severity of optic nerve hypoplasia

BACKGROUND

Optic nerve hypoplasia (ONH) is a birth defect of unknown etiology and a leading cause of visual impairment in developed countries. Recent studies suggest that factors of deprivation and exposures of poor nutritional status, such as lower gestational weight gain (GWG), may be associated with increased risk of ONH. The present study describes the prenatal features of mothers of ONH cases, including prepregnancy BMI and GWG, and the associations with clinical features of disease severity.

METHODS

Retrospective study of prenatal records for cases of ONH enrolled in a research registry. Prepregnancy BMI and GWG were compared to maternal characteristics and clinical findings of ONH severity including bilaterality, hypopituitarism, and neuroradiographic abnormalities.

RESULTS

Compared to population-based normative data of births in the United States, mothers of ONH cases (n = 55) were younger (23.3 vs. 25.8 years; p = 0.03), with higher incidence of inadequate GWG (34.0% vs. 20.4%; p = 0.03) predominantly in the first and second trimesters. The presence of major brain malformations was associated with younger maternal age (21.6 [IQR 19.4, 24.7] vs. 24.9 years [IQR 22.1, 28.5] [p = 0.02]), primiparity (44.1% vs. 13.3%; p = 0.05) and decreased prepregnancy BMI (20.9 kg/m2 [19, 22.5] vs. 25.5 kg/m2 [21.3, 28.2]; p < 0.01).

CONCLUSION

Decreased prepregnancy BMI and inadequate GWG correlated with clinical features of ONH severity, specifically bilateral disease and presence of major brain malformations.

Delineating septo-optic dysplasia

BACKGROUND

Septo-optic dysplasia (SOD), once a variable triad of septum pellucidum defects (SPDs), optic nerve hypoplasia (ONH), and hypopituitarism, has had multiple findings added, with uncertain causes, definitions, and limits.

METHOD

Literature review.

RESULTS

SOD is a complex vascular sequence with confounders.

CONCLUSIONS

Proximal anterior cerebral artery trunk disruptions cause overlapping primary effects, giving ONH alone most often, and isolated SPD less. ONH disruptions can spread to pituitary, SPD disruptions to the cerebral cortex, causing schizencephaly and related anomalies. Pituitary defects are rare without ONH, and cortical findings are rare without SPD. Extensions are unidirectional, so isolated pituitary or cortical defects are separate from SOD. Micro- an- ophthalmia, a suggested ONH variant, is not part of SOD. Disruption by-products can affect development, causing cognitive and endocrine issues, and structural anomalies such as corpus callosum thinning, ventriculomegaly, and hippocampal and olfactory findings. Limbic extensions may also contribute to the same structural defects as by-products. Midline CNS developmental anomalies can act as disruptive foci, most likely through vascular variants, but have separate pathogenesis. Relative frequencies of specific pituitary hormone defects change as SOD rates increase. Increasing relative rates of midline CNS developmental defects and cortical anomalies are consistent with rising levels of exogenous exposures sensitizing to midline predispositions.

Hypothesis: By-products of vascular disruption carried in the CSF affect prenatal brain development

Prenatal CNS disruptions can be associated with physically separate findings. Examples include cognitive issues in septo-optic dysplasia and sporadic and WNT1-related unilateral cerebellar hypoplasia, and physical findings such as thinning of the corpus callosum, ventriculomegaly, hippocampal abnormalities, olfactory tract and bulb hypoplasia, and distant cortical dysplasias with schizencephaly. Similar effects to toxicities with intraventricular hemorrhage in prematurity could occur earlier in development. CSF transportation of disruption by-products would provide access to vulnerable areas through inflammatory effects on blood-brain barrier permeability. Outcomes are influenced by location and volume of byproducts in the CSF, timing, transport, and inflammatory responses. A particular association of vermis disruption with cognitive issues may be related to CSF flow distortions that avoid toxin dilutions in the third ventricle. Symmetrical contralateral cortical dysplasia with schizencephaly may reflect immunovascular field-related vulnerabilities seen in situations such as vitiligo.

Pathophysiological Heterogeneity of the BBSOA Neurodevelopmental Syndrome

The formation and maturation of the human brain is regulated by highly coordinated developmental events, such as neural cell proliferation, migration and differentiation. Any impairment of these interconnected multi-factorial processes can affect brain structure and function and lead to distinctive neurodevelopmental disorders. Here, we review the pathophysiology of the Bosch–Boonstra–Schaaf Optic Atrophy Syndrome (BBSOAS; OMIM 615722; ORPHA 401777), a recently described monogenic neurodevelopmental syndrome caused by the haploinsufficiency of NR2F1 gene, a key transcriptional regulator of brain development. Although intellectual disability, developmental delay and visual impairment are arguably the most common symptoms affecting BBSOAS patients, multiple additional features are often reported, including epilepsy, autistic traits and hypotonia. The presence of specific symptoms and their variable level of severity might depend on still poorly characterized genotype–phenotype correlations. We begin with an overview of the several mutations of NR2F1 identified to date, then further focuses on the main pathological features of BBSOAS patients, providing evidence—whenever possible—for the existing genotype–phenotype correlations. On the clinical side, we lay out an up-to-date list of clinical examinations and therapeutic interventions recommended for children with BBSOAS. On the experimental side, we describe state-of-the-art in vivo and in vitro studies aiming at deciphering the role of mouse Nr2f1, in physiological conditions and in pathological contexts, underlying the BBSOAS features. Furthermore, by modeling distinct NR2F1 genetic alterations in terms of dimer formation and nuclear receptor binding efficiencies, we attempt to estimate the total amounts of functional NR2F1 acting in developing brain cells in normal and pathological conditions. Finally, using the NR2F1 gene and BBSOAS as a paradigm of monogenic rare neurodevelopmental disorder, we aim to set the path for future explorations of causative links between impaired brain development and the appearance of symptoms in human neurological syndromes.

Pathogenic NR2F1 variants cause a developmental ocular phenotype recapitulated in a mutant mouse model

Pathogenic NR2F1 variants cause a rare autosomal dominant neurodevelopmental disorder referred to as the Bosch-Boonstra-Schaaf Optic Atrophy Syndrome. Although visual loss is a prominent feature seen in affected individuals, the molecular and cellular mechanisms contributing to visual impairment are still poorly characterized. We conducted a deep phenotyping study on a cohort of 22 individuals carrying pathogenic NR2F1 variants to document the neurodevelopmental and ophthalmological manifestations, in particular the structural and functional changes within the retina and the optic nerve, which have not been detailed previously. The visual impairment became apparent in early childhood with small and/or tilted hypoplastic optic nerves observed in 10 cases. High-resolution optical coherence tomography imaging confirmed significant loss of retinal ganglion cells with thinning of the ganglion cell layer, consistent with electrophysiological evidence of retinal ganglion cells dysfunction. Interestingly, for those individuals with available longitudinal ophthalmological data, there was no significant deterioration in visual function during the period of follow-up. Diffusion tensor imaging tractography studies showed defective connections and disorganization of the extracortical visual pathways. To further investigate how pathogenic NR2F1 variants impact on retinal and optic nerve development, we took advantage of an Nr2f1 mutant mouse disease model. Abnormal retinogenesis in early stages of development was observed in Nr2f1 mutant mice with decreased retinal ganglion cell density and disruption of retinal ganglion cell axonal guidance from the neural retina into the optic stalk, accounting for the development of optic nerve hypoplasia. The mutant mice showed significantly reduced visual acuity based on electrophysiological parameters with marked conduction delay and decreased amplitude of the recordings in the superficial layers of the visual cortex. The clinical observations in our study cohort, supported by the mouse data, suggest an early neurodevelopmental origin for the retinal and optic nerve head defects caused by NR2F1 pathogenic variants, resulting in congenital vision loss that seems to be non-progressive. We propose NR2F1 as a major gene that orchestrates early retinal and optic nerve head development, playing a key role in the maturation of the visual system.

Autistic-Like Features in Visually Impaired Children: A Review of Literature and Directions for Future Research

There remains great interest in understanding the relationship between visual impairment (VI) and autism spectrum disorder (ASD) due to the extraordinarily high prevalence of ASD in blind and visually impaired children. The broad variability across individuals and assessment methodologies have made it difficult to understand whether autistic-like symptoms shown by some children with VI might reflect the influence of the visual deficit, or represent a primary neurodevelopmental condition that occurs independently of the VI itself. In the absence of a valid methodology adapted for the visually impaired population, diagnosis of ASD in children with VI is often based on non-objective clinical impression, with inconclusive prevalence data. In this review, we discuss the current state of knowledge and suggest directions for future research.

Blindness and Autism: Parents’ Perspectives on Diagnostic Challenges, Support Needs and Support Provision

Autism spectrum disorder (ASD), with or without intellectual disability (ID), is common in children with congenital blindness. This complex combination of disabilities often involves many challenges for the family. This study explored parents’ experiences of having a child with blindness and ASD (with or without ID), their support needs and experiences of the support provided. Interviews with eight parents, representing six families, were performed. The parents emphasized that assessment and diagnostic procedures must be performed by professionals with expertise in blind children’s development, and ASD. The support was often perceived as fragmented and did not correspond to the families’ needs. The results suggest that national guidelines should be produced, to ensure a more coordinated and tailored support to these families.

Congenital blindness and autism spectrum disorder (ASD): diagnostic challenges and intervention options

The case of a 6-year-old boy with congenital blindness and features suggestive of autism spectrum disorder (ASD) is reported. He presented to a developmental paediatrician with global developmental delay, worsening self-injurious behaviours and difficulties in social interaction, transitions and interactive play. He demonstrated poor response to his name, rigidity, repetitive behaviours and had a sensory profile suggestive of ASD. This paper discusses the challenges in diagnosing and managing ASD in visually impaired children.

Orbital MRI versus fundus photography in the diagnosis of optic nerve hypoplasia and prediction of vision

INTRODUCTION

In patients with optic nerve hypoplasia (ONH), the visualisation of the optic disc can be challenging and the definitive diagnosis difficult to ascertain without fundus photography. The use of MRI for diagnosis has been reported as a diagnostic alternative with conflicting results. We retrospectively analysed a disease registry to determine the reliability of orbital MRI measurements of the optic nerve diameter to diagnose ONH, and the correlation with vision outcomes.

MATERIALS AND METHODS

From a cohort of 140 patients with ONH (13% unilateral) that had reached age 5 years, we identified 43 subjects who had orbital MRI in addition to fundus photography performed prior to 2 years of age. We compared measurements of the optic nerve diameter from orbital MRI scans to the standard relative optic disc size (disc diameter/disc-macula (DD/DM) distance) by fundus photography. All patients had visual acuity tested at age 5 years. Spearman's correlation coefficient was used to determine the correlation of orbital MRI measurements and fundus photography with the diagnosis of ONH, and with vision outcomes.

RESULTS

Relative disc size (DD/DM)<0.35 showed 100% sensitivity and 100% specificity for the diagnostic confirmation of ONH. The optic nerve diameter measurements by orbital MRI displayed a moderate correlation (r_s=0.471; p<0.001) with DD/DM and moderate sensitivity for the diagnosis of ONH. Final visual acuity correlated well with DD/DM measurements by fundus photography (r_s=-0.869; p<0.001) and moderately with optic nerve diameter by orbital MRI (r_s=-0.635; p<0.001).

DISCUSSION

Orbital optic nerve diameter from MRI scans has moderate reliability in diagnosing ONH and predicting vision outcomes. Fundus photography for measurements of the optic nerve size should remain the reference for diagnostic confirmation of ONH. These data further support the prognostic value of fundus photography for eventual vision outcomes in this population.

Endocrine morbidity in midline brain defects: Differences between septo-optic dysplasia and related disorders

BACKGROUND

Septo-optic dysplasia (SOD) is a heterogeneous congenital condition. The aim of this study was to investigate the clinical phenotypes of a large cohort of children with SOD, Multiple Pituitary Hormone Deficiency (MPHD) and Optic Nerve Hypoplasia (ONH), with a focus on endocrine testing.

METHODS

Retrospective single-centre longitudinal study of children with SOD (n:171), MPHD (n:53) and ONH (n:35). SOD+ and SOD- indicate patients with or without hypopituitarism, respectively.

FINDINGS

All deficits were more frequent and occurred earlier in MPHD than SOD+ [Hazard Ratios (HR): 0·63(0·45,0·89) for GH, 0·48(0·34,0·69) for TSH, 0·55(0·38,0·80) for ACTH, 0·28(0·11,0·68) for gonadotropins], except Diabetes Insipidus (DI) [HR: 2·27(0·88,5·9)]. Severe hypothalamo-pituitary (H-P) abnormalities were more frequent in MPHD [80·0% vs 41·6%, p<0·0001 for Ectopic Posterior Pituitary (EPP)]. Stalk and PP abnormalities were associated with more severe endocrine phenotypes and placed a subgroup of SOD+ at risk of developing deficits earlier. SOD and ONH shared heterogeneous phenotypes ranging from pubertal delay to precocity and from leanness to extreme obesity, whilst MPHD had GnD and obesity only. Mortality was recorded in 4·2% (6/144) SOD and 3·2% (1/31) ONH, and only in patients with multisystem phenotypes.

INTERPRETATION

More than a single disease, SOD represents a spectrum of malformative conditions involving different brain structures and characterised by a dynamic and sequential nature of endocrine. In contrast, MPHD displays a more homogeneous phenotype of (mainly) anterior pituitary early-onset failure. Stalk and PP abnormalities place a subgroup of SOD+ at a higher risk of early-onset deficits. Additionally, there are striking differences between the SOD and MPHD cohorts in terms of pubertal progression. The shared phenotypes between ONH and SOD could be partly explained by common hypothalamic dysfunction. The differences between the cohorts are important as they may aid in planning management and preventing morbidity by dictating earlier interventions.

FUNDING

M.C., M.G., and N.I. were supported by the European Society of Paediatric Endocrinology (ESPE) through ESPE Clinical Fellowships.

Onset of pituitary hormone deficiencies in optic nerve hypoplasia: a temporal trend analysis of 32 children at Mayo Clinic

Background The objective of this study was to evaluate the age at onset and frequency of individual pituitary hormone deficiencies (PHDs) in optic nerve hypoplasia (ONH). Methods We performed a retrospective chart review of patients ≤21 years of age evaluated between 1996 and 2014. Patients were included if they had: (1) ONH diagnosed by an ophthalmologist and/or magnetic resonance imaging (MRI), (2) documentation of pituitary hormone function on at least two separate occasions and (3) at least one PHD documented or a midline abnormality of the brain on MRI. Results Thirty-two patients (18 females, 14 males) were included (median age, 8 years [range, 1.1-21.0 years]). All patients had ONH (bilateral, n = 31; unilateral, n = 1) and at least one midline abnormality of the brain. At least one PHD was present in 75% of patients (n = 24). The remaining 25% of patients (n = 8) did not develop any PHD at least until the last follow-up (<2-8.6 years of follow-up), despite the presence of ONH and a midline abnormality of the brain. The median age (years) at diagnosis of antidiuretic hormone (ADH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH) and growth hormone (GH) deficiencies was 0.5, 0.6, 0.7 and 1.6, respectively. Twenty-three percent of all PHDs were identified during the neonatal period, 56% by 12 months and 72% by 36 months of age. The latest age at diagnosis of GH, ACTH and TSH deficiencies was 9.6, 9.9 and 12.6 years, respectively. Conclusions The majority of the PHDs in ONH develop within the first 3 years of life. We propose evaluation for endocrinopathies at the time of diagnosis of ONH, with repeat assessment for new deficiencies every 3-4 months until age 3 years and at least semi-annually until growth and puberty are complete.

Pediatric liver diseases and ocular changes: What hepatologists and ophthalmologists should know and share with each other

Several rare pediatric liver disorders are accompanied by ophthalmic signs whose awareness and early identification may be of value in confirming/accelerating their diagnosis. Many of these signs are asymptomatic and can only be detected with an ophthalmological examination. Corneal signs are described in patients with Wilson's disease, Alagille's syndrome and some liver storage diseases. Cataract plays an important role to diagnose galactosemia. Retinal involvement is seen in some peroxisomal disorders (e.g. Zellweger's syndrome), in mucopolysaccharidoses (pigmentary retinopathy), and in Niemann-Pick disease (macular cherry red spot). In mucopolysaccharidoses optic nerve can be involved as optic atrophy secondary to pigmentary retinopathy or to chronic papilledema. Children with neonatal cholestasis due to hypopituitarism may present septo-optic dysplasia. Several infectious agents have an ophthalmological/hepatic involvement in the fetal life and/or thereafter. Some mitochondrial liver diseases, such as Pearson's syndrome, present pigmentary retinopathy and a chronic progressive external ophthalmoplegia. Finally, some drugs while protecting the liver may damage the ocular system as seen with long-term glucocorticoids and Nitisinone administration. This review provides a synopsis of those conditions that hepatologists and ophthalmologists should share among themselves to better take care of patients. Synoptic tables are presented to facilitate the mutual understanding of the issues.

Autism in Children With Cerebral and Peripheral Visual Impairment: Fact or Artifact?

The aim of this study was to evaluate the occurrence and clinical characteristics of autism spectrum disorder in visually impaired children. In total, 273 participants, 214 with cerebral causes of vision impairment and 59 with peripheral causes, were assessed using multiple assessment methods and adapted for individuals with vision loss. We found that autism spectrum disorder was more prevalent in the visually impaired compared to general population, and that the prevalence varied according to the type of visual disorder (2.8% for cerebral and 8.4% for peripheral visual impairment). In subjects with cerebral visual impairment, the presence of autistic symptoms was consistent with the diagnosis of autism spectrum disorder. In children with peripheral visual impairment, certain symptoms related to visual loss overlapped with the clinical features of autism spectrum disorder, thus making clinical diagnosis more challenging. The development of assessment tools that take into account the type and level of visual impairment and validation testing in a larger population sample are needed in order to confirm these initial findings regarding the diagnosis of autism spectrum disorder in visually impaired children.

High prevalence of pituitary hormone deficiency in both unilateral and bilateral optic nerve hypoplasia

AIM

This study examined the prevalence of neurological impairment and pituitary hormone deficiency (PHD) in patients with unilateral and bilateral optic nerve hypoplasia (ONH).

METHODS

A population-based cross-sectional cohort study of 65 patients (51% female) with ONH was conducted in Stockholm. Of these were 35 bilateral and 30 unilateral. The patients were below 20 years of age, living in Stockholm in December 2009 and found through database searching. The median age at the analysis of the results in January 2018 was 16.1 years (range 8.1-27.5 years). Neurological assessments and blood sampling were conducted, neuroradiology was reviewed and growth curves were analysed. Diagnoses of PHDs were based on clinical and biochemical evidence of hormone deficiency.

RESULTS

Neurological impairments were identified in 47% of the patients and impairments in gross and fine motor function were more prevalent in bilateral ONH (p < 0.001). In addition, 9% had cerebral palsy and 14% had epilepsy. The prevalence of PHD was 29 and 19% had multiple PHD.

CONCLUSION

Children with ONH had a high risk of neurological impairment, especially in bilateral disease. Both unilateral and bilateral ONH signified an increased prevalence of PHD and all these children should be endocrinologically followed up until completed puberty.

Pituitary Dysfunction in Pediatric Patients with Optic Nerve Hypoplasia: A Retrospective Cohort Study (1975-2014)

BACKGROUND/AIMS

The risk factors for pituitary hormone dysfunction (PHD) in children with optic nerve hypoplasia (ONH) are not well understood. This study identified the type, timing, and predictors of PHD in children with ONH.

METHODS

ONH patient charts were reviewed retrospectively. The incidence rate of PHD was calculated assuming a Poisson distribution. Predictors of PHD were identified through a multivariable Cox proportional hazards model.

RESULTS

Among 144 subjects with ONH, 49.3% (n = 71) developed PHD over 614.7 person-years of follow-up. The incidence was 11.55 (95% confidence interval [CI]: 9.02-14.57/100 person-years). The median time to first PHD was 2.88 (interquartile range: 0.02-18.72) months. Eighty-two percent developed their first PHD by their 5th and 90% by their 10th birthday, and 89% within 5 years of ONH diagnosis. Prematurity (adjusted hazard ratio [aHR]: 0.33; 95% CI: 0.1-1.07), blindness (aHR: 1.72; 95% CI: 1.03-2.86), maternal substance abuse (aHR: 1.51; 95% CI: 0.91-2.48), abnormal posterior pituitary (aHR: 3.8; 95% CI: 2.01-7.18), and hypoplastic/absent anterior pituitary (aHR: 2.52; 95% CI: 1.29-4.91) were significant predictors of PHD.

CONCLUSIONS

The clinical predictors of PHD included blindness, pituitary gland abnormalities, and maternal substance abuse. These predictors help clinical decision-making related to the need for and frequency of hormone testing in pediatric patients with ONH.

Children with blindness - major causes, developmental outcomes and implications for habilitation and educational support: a two-decade, Swedish population-based study

PURPOSE

The aim was to describe the population of children with congenital or early infancy blindness in Sweden, with regard to causes of blindness and prevalence of neurodevelopmental impairments.

METHODS

Medical, psychological and pedagogical records of Swedish children with congenital or early infancy blindness (total blindness or light perception at the most) born in 1988-2008 were analysed regarding year of birth, gender, cause of blindness, gestational age, associated neurological disorders/syndromes, associated neurodevelopmental impairments, cognitive level and type of school placement.

RESULTS

A total of 150 individuals, 80 girls and 70 boys, were identified, corresponding to a prevalence of 7/100 000. Five causes of blindness dominated, constituting 76% of all represented aetiologies: retinopathy of prematurity (ROP), optic nerve hypoplasia (ONH), Leber congenital amaurosis (LCA), optic nerve atrophy (ONA) and microphthalmia/anophthalmia. Nearly three of four children in the study population had at least one additional disability besides blindness; the most common being intellectual disability (ID) and autism spectrum disorder (ASD). More than half of the population had more than one additional disability. Autism spectrum disorder (ASD) was most common in children with ONH, ROP, LCA and microphthalmia/anophthalmia.

CONCLUSION

In children born within the last decades, isolated blindness is uncommon and the rate of multidisabilities is high. Autism spectrum disorder (ASD) seems to be more strongly associated with specific aetiological subgroups. Further development of the support to families and schools should be based on knowledge about the considerable heterogeneity of the population of children with blindness, and the common occurrence of coexisting neurodevelopmental disorders, especially ID and ASD.

Children with optic nerve hypoplasia face a high risk of neurodevelopmental disorders

AIM

Optic nerve hypoplasia (ONH) is a congenital ocular malformation that has been associated with neurodevelopmental disorders, but the prevalence in unilateral disease and less severe visual impairment is unknown. We studied intellectual disability and autism spectrum disorders (ASDs) in patients with ONH.

METHODS

This was a population-based cross-sectional cohort study of 65 patients (33 female) with ONH below 20 years of age, living in Stockholm in December 2009, with data analysed in January 2016. Of these 35 were bilateral and 30 were unilateral. Neurodevelopmental disorders were diagnosed or confirmed by neurological assessments, the Five to Fifteen parent questionnaire and reviewing previous neuropsychological investigations or conducting neuropsychological tests.

RESULTS

Bilateral ONH patients had lower mean full scale intelligence quotient scores than unilateral patients (84.4 and 99.4, respectively, p = 0.049). We assessed intellectual disability in 55 eligible patients, and it was more common in patients with bilateral ONH (18 of 32, 56%) than unilateral ONH (two of 23, 9%, p < 0.001). ASDs were diagnosed in seven of 42 (17%) patients.

CONCLUSION

Children with bilateral ONH had a high risk of neurodevelopmental disorders, especially intellectual disability. The risk was lower in unilateral ONH, but the levels of neurodevelopmental disorders warrant screening of both groups.

Pilot study: Sensory integration processing disorders in children with optic nerve hypoplasia spectrum

This study aimed to explore the sensory processing profiles of children with the spectrum of optic nerve hypoplasia (ONH). Caregivers completed the Short Sensory Profile (SSP), the Social Communication Questionnaire (SCQ), and the Vineland Adaptive Behaviour Scale (VABS) interview. The study demonstrated that children with ONH present with sensory integration dysfunction (SID), in their intact senses, and that autistic spectrum condition (ASC) was the best predictor of SID, rather than visual loss, or level of intellectual disability in these children. The results indicate that assessment and monitoring of SID in children with ONH is crucial.

Challenges and Successful Pedagogical Strategies: Experiences from Six Swedish Students with Blindness and Autism in Different School Settings

The prevalence of autism in children with blindness is much higher than in the general population. There are many challenges regarding the school situation for children with this complex dual disability. This study explored challenges and successful strategies in school for a sample of six Swedish children with blindness and autism, with and without intellectual disability, through qualitative interviews with students, teachers and parents. All students displayed executive functioning deficits, and the teaching situation entailed several challenges. Our research points to the importance of adopting evidence-based practices for ASD, but adapted according to the students lack of vision. For this to be possible, close collaboration between teachers, parents and specialists in the field of visual impairment and autism is necessary.

Congenital anomalies of the optic disc: insights from optical coherence tomography imaging

PURPOSE OF REVIEW

Congenital anomalies of the optic nerve are rare but significant causes of visual dysfunction in children and adults. Accurate diagnosis is dependent on a thorough funduscopic examination, but can be enhanced by imaging information garnered from optical coherence tomography (OCT). We review common congenital optic nerve anomalies, including optic disc pit, optic nerve coloboma, morning glory disc anomaly, and hypoplasia of the optic nerve, review their systemic associations, and discuss insights from OCT imaging.

RECENT FINDINGS

Optic disc pits are a result of a defect in the lamina cribrosa and abnormal vitreomacular adhesions have been shown to cause maculopathy. In patients with optic nerve colobomas, OCT can be instrumental in diagnosing choroidal neovascularization, a rare but visually devastating complication. The pathogenesis of morning glory disc anomaly has been more clearly elucidated by OCT as occurring from a secondary postnatal mesenchymal abnormality rather than only the initial neuroectodermal dysgenesis of the terminal optic stalk in isolation. OCT studies of optic nerve hypoplasia have demonstrated significant thinning of the inner and outer retinal layers of the perifoveal region and thicker layers in the fovea itself, resulting in a foveal hypoplasia-like pathology, that is, significantly correlated to poorer visual outcomes.

SUMMARY

OCT provides detailed in-vivo analysis of these anatomic anomalies and their resulting pathologies, shedding new insights on the pathogenesis, diagnosis, and potential visual outcomes of these conditions in children. Further study employing OCT to elucidate structure-function relationships of congenital optic nerve anomalies will help expand the role of OCT in clinical practice related to diagnosis, prognosis, and management of these entities.

Neuroimaging and endocrine disorders in paediatric optic nerve hypoplasia

Purpose

Optic nerve hypoplasia (ONH) is one of the leading causes of blindness among children. The purpose of this retrospective study is to determine the risk factors and association between brain MRI findings, pituitary abnormalities and endocrine disorders with the presence of ONH.

Methods

A retrospective review of patients seen at paediatric ophthalmology clinics from January 2006 to December 2016 at Children’s Hospital and Medical Center and the University of Nebraska Medical Center was performed. All patients with a documented diagnosis of ONH or septo-optic dysplasia were identified. MRI and endocrinology results were analysed by masked examiners.

Results

Out of 77 patients, overall incidence of abnormal pituitary on MRI was 35.1% and the incidence of endocrine abnormalities was 37.7%. Of the 57 patients with bilateral ONH, 23 (40.4%) had an abnormal pituitary while 4 of the 20 patients (20.0%) with unilateral ONH had an abnormal pituitary on MRI. The sensitivity and specific of brain MRI as signs of endocrinopathy are 67.9% and 83.3%, respectively.

Conclusion

This study has determined that abnormal MRI findings do not have the sensitivity to predict endocrinopathy, nor does a normal MRI rule out possible endocrine abnormalities. When patients with ONH present with normal neurological examinations, normal endocrine workup and normal developmental milestones, a MRI of the brain may be deferred until new indications arise. Regardless of the MRI status, children with ONH should have a comprehensive endocrine evaluation and continue to have routine endocrine follow-up.

Epidemiology of blindness in children

An estimated 1.4 million of the world's children are blind. A blind child is more likely to live in socioeconomic deprivation, to be more frequently hospitalised during childhood and to die in childhood than a child not living with blindness. This update of a previous review on childhood visual impairment focuses on emerging therapies for children with severe visual disability (severe visual impairment and blindness or SVI/BL).For children in higher income countries, cerebral visual impairment and optic nerve anomalies remain the most common causes of SVI/BL, while retinopathy of prematurity (ROP) and cataract are now the most common avoidable causes. The constellation of causes of childhood blindness in lower income settings is shifting from infective and nutritional corneal opacities and congenital anomalies to more resemble the patterns seen in higher income settings. Improvements in maternal and neonatal health and investment in and maintenance of national ophthalmic care infrastructure are the key to reducing the burden of avoidable blindness. New therapeutic targets are emerging for childhood visual disorders, although the safety and efficacy of novel therapies for diseases such as ROP or retinal dystrophies are not yet clear. Population-based epidemiological research, particularly on cerebral visual impairment and optic nerve hypoplasia, is needed in order to improve understanding of risk factors and to inform and support the development of novel therapies for disorders currently considered 'untreatable'.

Predictive value of N95 waveforms of pattern electroretinograms (PERGs) in children with optic nerve hypoplasia (ONH)

PURPOSE

As part of a long-term, prospective study of prenatal and clinical risk factors for optic nerve hypoplasia (ONH) at Children's Hospital Los Angeles, pattern ERGs (PERGs) were evaluated for prognostic value using an automated objective and robust analytical method.

METHODS

Participants were 33 children with ophthalmoscopically diagnosed ONH [disc diameter-to-disc macula ratio (DD/DM) less than 0.35 in one or both eyes on fundus photographs]. Using cycloplegia and chloral hydrate sedation in one session before 26 months of age, we recorded PERGs to checkerboard reversal using five check sizes. Participants were followed with clinical and psychometric testing until 5 years of age. PERGs were analysed using automated robust statistics based on magnitude-squared coherence and bootstrapping optimized to objectively quantify PERG recovery in the challenging recordings encountered in young patients. PERG measures in the fixating or better-seeing eyes were compared with visual outcome data.

RESULTS

PERG recording was complete to at least three check sizes in all eyes and to all five sizes in 79%. Probability of recording a PERG that is significantly different from noise varied with check size from 73% for the largest checks to 30% for the smallest checks (p = 0.002); smaller waveforms were associated with earlier implicit times. The presence of significant PERGs in infancy is associated with better visual outcomes; the strongest association with visual outcome was for the threshold check size with a significant N95 component (ρ = 0.398, p = 0.02).

CONCLUSIONS

Automated statistically robust signal-processing techniques reliably and objectively detect PERGs in young children with ONH and show that congenital deficits of retinal ganglion cells are associated with diminished or non-detectable PERGs. The later negativity, N95, was the best indicator of visual prognosis and was most useful to identify those with good visual outcomes (≤0.4 LogMAR). Although PERGs reflect function of the inner layers of the central retina, they lack the specificity required to determine prognosis reliably in individual cases.

Brain Malformations Do Not Predict Hypopituitarism in Young Children with Optic Nerve Hypoplasia

BACKGROUND

Optic nerve hypoplasia (ONH), a leading cause of pediatric blindness, is associated with brain malformations and hypopituitarism in the constellation known as septo-optic dysplasia. Neuroimaging is used to anticipate hypopituitarism, but with unconfirmed reliability. We report prospective findings on the association of hypopituitarism with brain malformations.

METHODS

Children (<24 months) with ONH (n = 146; 87% bilateral) underwent baseline MRI and annual examinations and hormonal testing. Hypopituitarism status at age 5 years was classified.

RESULTS

A total of 74% had brain malformation(s). Hypopituitarism (69%) was not associated with brain malformations (p = 0.351); this persisted after adjusting for the laterality of ONH and the timing of MRI (padj = 0.869). No association was noted for absent septum pellucidum (38%; p = 0.073), corpus callosum abnormality (51%; p = 0.625), and major malformations (22%; p = 0.407). A malformation conferred a positive predictive value of 71% (95% CI: 62%, 80%), and a negative predictive value of 37% (95% CI: 22%, 54%). Overall, 10% (n = 15) of the cohort presented with a triad of absent septum pellucidum, corpus callosum abnormality, and other major malformation; only half (n = 8) of these had hypopituitarism. All 13 subjects with pituitary malformations manifested hypopituitarism, conferring predictive values of 100% (positive) and 34% (negative).

CONCLUSIONS

Hypopituitarism and brain malformations are highly prevalent, but have unrelated associations with ONH. Brain MRI in infants and toddlers with ONH is an unreliable screen for hypopituitarism risk.

Congenital optic nerve anomalies

OBJECTIVE

To update the current knowledge about congenital optic disc anomalies.

METHODS

A comprehensive literature search was performed in the major biomedical databases.

RESULTS

Patients with these anomalies usually have poor vision in infancy. Refractive errors are common, and serous retinal detachment may develop in some of these anomalies. It is critically important to clinically differentiate between these congenital optic disc anomalies, as central nervous system malformations are common in some, whereas others may be associated with systemic anomalies.

CONCLUSIONS

Congenital optic disc anomalies are a heterogeneous group of pathologies with characteristic fundus appearance and systemic associations. We should always try to make a correct diagnosis, in order to ask for specific tests, as well as to provide an adequate follow-up.

Spectrum of Clinical and Associated MR Imaging Findings in Children with Olfactory Anomalies

BACKGROUND AND PURPOSE

The olfactory apparatus, consisting of the bulb and tract, is readily identifiable on MR imaging. Anomalous development of the olfactory apparatus may be the harbinger of anomalies of the secondary olfactory cortex and associated structures. We report a large single-site series of associated MR imaging findings in patients with olfactory anomalies.

MATERIALS AND METHODS

A retrospective search of radiologic reports (2010 through 2014) was performed by using the keyword "olfactory"; MR imaging studies were reviewed for olfactory anomalies and intracranial and skull base malformations. Medical records were reviewed for clinical symptoms, neuroendocrine dysfunction, syndromic associations, and genetics.

RESULTS

We identified 41 patients with olfactory anomalies (range, 0.03-18 years of age; M/F ratio, 19:22); olfactory anomalies were bilateral in 31 of 41 patients (76%) and absent olfactory bulbs and olfactory tracts were found in 56 of 82 (68%). Developmental delay was found in 24 (59%), and seizures, in 14 (34%). Pituitary dysfunction was present in 14 (34%), 8 had panhypopituitarism, and 2 had isolated hypogonadotropic hypogonadism. CNS anomalies, seen in 95% of patients, included hippocampal dysplasia in 26, cortical malformations in 15, malformed corpus callosum in 10, and optic pathway hypoplasia in 12. Infratentorial anomalies were seen in 15 (37%) patients and included an abnormal brain stem in 9 and an abnormal cerebellum in 3. Four patients had an abnormal membranous labyrinth. Genetic testing was performed in 23 (56%) and findings were abnormal in 11 (48%).

CONCLUSIONS

Olfactory anomalies should prompt careful screening of the brain, skull base, and the pituitary gland for additional anomalies. Genetic testing should be considered.

Association of refractive error with optic nerve hypoplasia

PURPOSE

To evaluate the association of refractive error with optic nerve hypoplasia (ONH).

METHODS

A total of 30 ONH subjects were recruited and underwent comprehensive eye exams. Refractive error data from this group was compared to data from a group of 3232 non-ONH subjects from the same facility. Spherical equivalent was calculated to assess refractive error. Multiple logistic regression was used to evaluate the relationship between ONH and refractive error while controlling for age, race, and gender.

RESULTS

The prevalence of hyperopia (≥+1.00 D), myopia (<-0.75 D), and anisometropia (≥1.00 D) was higher in ONH subjects than in controls. ONH subjects were 9.1 times more likely to be hyperopic than emmetropic (OR = 9.1, 95% CI = 2.9-28.4, p < 0.001) and 3.8 times more likely to be myopic than emmetropic (OR = 3.8, 95% CI = 1.2-11.5, p = 0.02). Unilateral ONH subjects were 10.0 times more likely to have anisometropia than controls (OR = 10.0, 95% CI = 3.9-25.6, p < 0.0001). Bilateral ONH subjects were 3.8 times more likely to have anisometropia than controls (OR = 3.8, 95% CI = 1.1-12.7, p = 0.03).

CONCLUSIONS

Optic nerve hypoplasia subjects were more likely than control subjects to exhibit significant refractive errors, particularly hyperopia. Anisometropia tended to be more likely to occur in subjects with unilateral ONH than in bilateral ONH. Based on our findings, we recommend that clinicians perform a comprehensive eye examination on all patients with ONH and prescribe for existing refractive error when visual acuity or general visual function can realistically be improved.

Efficacy of growth hormone replacement on anthropometric outcomes, obesity, and lipids in children with optic nerve hypoplasia and growth hormone deficiency

Background

Hypopituitarism and obesity are causes of major lifelong morbidity in patients with optic nerve hypoplasia (ONH). Growth hormone deficiency (GHD) affects the majority of children with ONH, though the degree of deficiency and variability of early growth patterns range from early severe retardation to normal initial growth. The utility of early GH replacement for improving anthropometric, body composition, and lipid outcomes in patients with ONH and GHD, especially those with normal initial height velocity, is unknown. This study examines the effects of GH replacement in a cohort of children with ONH and GHD.

Methods

Controlled clinical trial from 2005–2014. The study included 17 children with ONH and untreated GHD. Those meeting criteria for growth deceleration were assigned to treatment with recombinant human growth hormone (n = 5) while those with normal height velocity were randomized either to treatment (n = 5) or to observation (no intervention, n = 7). Study duration was 3 years. Primary outcome measures included stature, weight, weight-for-stature, and BMI standard deviation score (SDS) at study completion.

Results

Subjects on GH, irrespective of entry growth trajectory, grew more on average in stature than controls by a difference of 0.98 SDS by study end; this effect persisted after adjusting for baseline overweight status. Treatment had an effect on weight SDS only after adjusting for initial overweight status, resulting in an average increase of 0.83 SDS more than controls. Subjects who were overweight at the outset experienced greater gains in both weight and stature SDS. Treatment had no statistically significant impact on weight-for-stature or BMI SDS. A reduction in body fat percentage was observed in those treated, both before (−6.1 %) and after (−4.3 %) adjustment for initial overweight status.

Conclusion

Early GH replacement has a positive effect on short-term statural outcomes in children with ONH and GHD, even in those exhibiting normal initial linear growth. Results were less conclusive regarding treatment effects on body composition and lipids.

Central Diabetes Insipidus in Infancy With or Without Hypothalamic Adipsic Hypernatremia Syndrome: Early Identification and Outcome

CONTEXT

Neonatal central diabetes insipidus (CDI) with or without adipsia is a very rare complication of various complex hypothalamic disorders. It is associated with greater morbidity and a high risk of developing both hypernatremia and hyponatremia, due to the condition itself or secondary to treatment with vasopressin analogs or fluid administration. Its outcomes have yet to be evaluated.

OBJECTIVE

To investigate the clinical outcomes of patients with neonatal-onset CDI or adipsic CDI with hypernatremia.

DESIGN, SETTING, AND PARTICIPANTS

All patients diagnosed with neonatal CDI in a university hospital-based observational study and followed between 2005 and 2015 were included and analyzed retrospectively.

MAIN OUTCOME MEASURES

The various causes of CDI were grouped. Clinical outcome and comorbidities were analyzed.

RESULTS

Ten of the 12 patients had an underlying condition with brain malformations: optic nerve hypoplasia (n = 3), septo-optic dysplasia (n = 2), semilobar holoprosencephaly (n = 1), ectopic neurohypophysis (n = 3), and unilateral absence of the internal carotid artery (n = 1). The other two were idiopathic cases. During the median follow-up period of 7.8 (4.9-16.8) years, all but one patient displayed anterior pituitary deficiency. Transient CDI was found in three (25%) patients for whom a posterior pituitary hyperintense signal was observed with (n = 2) and without (n = 1) structural hypothalamic pituitary abnormalities, and with no other underlying cerebral malformations. Patients with permanent CDI with persistent adipsia (n = 4) and without adipsia (n = 5) required adequate fluid intake and various doses of desamino-D-arginine-8-vasopressin. Those with adipsia were more likely to develop hypernatremia (45 vs 33%), hyponatremia (16 vs 4%) (P < .0001), and severe neurodevelopmental delay (P < .05) than those without adipsia. Comorbidities were common. The underlying cause remains unknown at the age of 23 years for one patient with CDI and normal thirst.

CONCLUSION

Neonatal CDI may be transient or permanent. These vulnerable patients have high rates of comorbidity and require careful monitoring.

Endocrine and pubertal disturbances in optic nerve hypoplasia, from infancy to adolescence

Background

Endocrinologic abnormalities are a common co-morbidity in patients with optic nerve hypoplasia (ONH), however the impact on puberty is unknown. The purpose of this study was to examine rates of endocrine dysfunction and pubertal disturbances in a pediatric population of ONH.

Methods

A retrospective chart review was conducted on a cohort of children with ONH between January 2005 and March 2013. Endocrine dysfunction was determined based on laboratory evidence of hormone deficiency or hormone replacement. Pubertal disturbances were characterized based on presence of micropenis, tanner staging, menarche and hormone replacement. Pituitary abnormalities were classified using MRI findings. Descriptive statistics were used, and comparisons between groups were performed using the chi-square test.

Results

During the study period, 101 patients underwent an endocrine evaluation (median age: 2.3 years [0.76 – 6.5]). Hypopituitarism was present in 73% of patients with growth hormone deficiency (56%) and hypothyroidism (54%) being the most common. Pubertal disturbances (n = 19) were common; micropenis in 31% (13/42) of males and 2% with precocious puberty. Half of adolescents (n = 4/8) were diagnosed with gonadotropin deficiency. Patients with MRI pituitary abnormalities were more likely to have endocrine dysfunction than those without (p = 0.004). The sensitivity and specificity of MRI pituitary abnormalities for hypopituitarism was 54% and 92%, respectively.

Conclusions

A significant proportion of children with ONH have endocrine dysfunction. The high frequency of pubertal disturbances in this study emphasizes the need for long-term monitoring of developing endocrinopathy. While pituitary gland abnormalities are a good predictor of endocrine dysfunction, a normal pituitary gland does not rule out endocrinopathy.

Comparison of human expert and computer-automated systems using magnitude-squared coherence (MSC) and bootstrap distribution statistics for the interpretation of pattern electroretinograms (PERGs) in infants with optic nerve hypoplasia (ONH)

PURPOSE

Pattern electroretinograms (PERGs) have inherently low signal-to-noise ratios and can be difficult to detect when degraded by pathology or noise. We compare an objective system for automated PERG analysis with expert human interpretation in children with optic nerve hypoplasia (ONH) with PERGs ranging from clear to undetectable.

METHODS

PERGs were recorded uniocularly with chloral hydrate sedation in children with ONH (aged 3.5-35 months). Stimuli were reversing checks of four sizes focused using an optical system incorporating the cycloplegic refraction. Forty PERG records were analysed; 20 selected at random and 20 from eyes with good vision (fellow eyes or eyes with mild ONH) from over 300 records. Two experts identified P50 and N95 of the PERGs after manually deleting trials with movement artefact, slow-wave EEG (4-8 Hz) or other noise from raw data for 150 check reversals. The automated system first identified present/not-present responses using a magnitude-squared coherence criterion and then, for responses confirmed as present, estimated the P50 and N95 cardinal positions as the turning points in local third-order polynomials fitted in the -3 dB bandwidth [0.25 … 45] Hz. Confidence limits were estimated from bootstrap re-sampling with replacement. The automated system uses an interactive Internet-available webpage tool (see http://clinengnhs.liv.ac.uk/esp_perg_1.htm).

RESULTS

The automated system detected 28 PERG signals above the noise level (p ≤ 0.05 for H0). Good subjective quality ratings were indicative of significant PERGs; however, poor subjective quality did not necessarily predict non-significant signals. P50 and N95 implicit times showed good agreement between the two experts and between experts and the automated system. For the N95 amplitude measured to P50, the experts differed by an average of 13% consistent with differing interpretations of peaks within noise, while the automated amplitude measure was highly correlated with the expert measures but was proportionally larger. Trial-by-trial review of these data required approximately 6.5 h for each human expert, while automated data processing required <4 min, excluding overheads relating to data transfer.

CONCLUSIONS

An automated computer system for PERG analysis, using a panel of signal processing and statistical techniques, provides objective present/not-present detection and cursor positioning with explicit confidence intervals. The system achieves, within an efficient and robust statistical framework, estimates of P50 and N95 amplitudes and implicit times similar to those of clinical experts.

Neuroimaging and clinical features of patients with optic nerve hypoplasia in Taiwan

PURPOSE

To investigate the clinical and neuroradiographic features of Chinese patients with optic nerve hypoplasia (ONH).

METHODS

This was a retrospective case series study. The medical records and magnetic resonance imaging (MRI) studies of patients diagnosed with ONH from September 2001 to December 2013 in the neuro-ophthalmology clinic of Taipei Veterans General Hospital were reviewed.

RESULTS

A total of eight eyes of five patients with ONH were enrolled in this study (1 male, 4 females). The mean age at diagnosis was 14.5 ± 12.0 years (range 0.25-30 years). Ocular examination revealed approximately half of the eyes had tortuous retinal vessels. In MRI studies, all patients had midline brain abnormalities including ectopic posterior pituitary gland (60%), agenesis of septum pellucidum (20%), and Rathke's cleft cyst (20%). Two patients had endocrinopathies-one suffered from hypopituitarism and the other had hyperprolactinemia. Both of them showed ocular findings of tortuous retinal vessels.

CONCLUSION

A high prevalence of midline brain abnormalities was noted in ONH patients of Chinese ethnicity. The presence of tortuous retinal vessels in patients with a midline brain anomaly may indicate the occurrence of endocrinopathy.

Optic nerve hypoplasia in children and adolescents; prevalence, ocular characteristics and behavioural problems

PURPOSE

To report prevalence, ocular characteristics and coexisting behavioural problems in children and adolescents with optic nerve hypoplasia (ONH), which is a common cause of visual impairment in children in western countries, often associated with neurological or endocrinological problems and where autism has been reported in severe cases with blindness.

METHODS

This is a population-based cross-sectional study of patients <20 years of age who had been diagnosed with ONH and lived in the county of Stockholm in December 2009. Ophthalmological assessments including fundus photographs with optic disc analyses were made. A questionnaire was used to screen for behaviour and development.

RESULTS

The prevalence of ONH in all living children <18 years of age in Stockholm was 17.3/100 000 with a prevalence of visual impairment (<0.3) of 3.9/100 000. In total, 66 patients, median age 9.3 years (0.6-19.4), 36 with bilateral and 30 with unilateral ONH, were included in the current study; 53 were re-examined clinically, group A, and 13 agreed to retrospective analyses of existing medical records, group B. Analyses of the optic discs were made in fundus photographs from 53 patients comparing a semi-automated (Retinal Size Tool) and a manual method (Zeki). There was a strong curvilinear correlation (r(S)  = -0.91 p < 0.0001 for both eyes). Behavioural problems were more common (p < 0.05) in bilateral ONH.

CONCLUSION

Optic nerve hypoplasia is a common ocular malformation with a prevalence of 17.3/100 000 children and adolescents <18 years of age in Stockholm. Unilateral ONH seems as common as bilateral.

Ophthalmologic features of Vici syndrome

PURPOSE

To report and compile the ophthalmological features critical to diagnosis of Vici syndrome, a rare congenital disorder characterized principally by agenesis of the corpus callosum, cataracts, cardiomyopathy, immune defects, and hypopigmentation.

METHODS

A child with Vici syndrome (OMIM 242840) is reported with emphasis on the ophthalmologic evaluation. Ophthalmologic assessments including fundus examination, visual evoked potentials (VEPs), and ocular coherence tomography are presented. These findings are compared with those identified in other published cases of children with Vici syndrome.

RESULTS

Ophthalmologic findings included bilateral nuclear and anterior polar cataracts, bilateral optic nerve atrophy, and mild fundus hypopigmentation. Evoked potentials recorded across the mid-occipital scalp demonstrated misrouting of optic pathways typical of albinism. Optical coherence tomography exhibited a poorly defined fovea demonstrating a lesser degree of foveal depression also consistent with ocular albinism. Review of reported children with Vici syndrome identifies bilateral cataracts, nystagmus, fundus hypopigmentation, visual impairment, and optic nerve hypoplasia as common ophthalmologic features.

CONCLUSIONS

Ophthalmologic findings are critical to the diagnosis of Vici syndrome. Most common are bilateral cataracts and relative fundus hypopigmentation. VEPs can identify misrouting of optic pathways typical of ocular albinism, thereby establishing the diagnosis in challenging cases.

Clinical and demographic associations with optic nerve hypoplasia in New Zealand

AIM

To identify the clinical features of optic nerve hypoplasia (ONH) and prevalence within a population of New Zealand children with severe visual impairment.

METHODS

Retrospective review of medical records of children with severe visual impairment registered with Blind and Low Vision Educational Network New Zealand.

RESULTS

Of 1500 children with severe visual impairment, 94 (6.3%) exhibited ONH, and 91 (97%) cases were bilateral. Of these 94 cases, 52 (55%) were males and ethnicities were European Caucasian (52%), Maori (40%), Pasifika (6%) and other (2%). Most children with ONH had poor vision, with 60% having ≤ 6/60 Snellen visual acuity equivalent. The median maternal age was 20.0 years old with 52% ≤ 20 years. There was a statistically significant over-representation of Maori ethnicity (40%) and young maternal age with age less than 20 years old (44%) in our cohort compared to the general population (14.6% and 7.4%, respectively; p<0.0001). Half had hypopituitarism, while neuroimaging abnormalities were detected in 60% cases. Cerebral neuroradiographic abnormalities were found to be associated with higher rate of developmental delay (OR 9.764 95% CI 3.246 to 29.373).

CONCLUSIONS

This is the first major study of visual impairment in New Zealand children, and it demonstrates that ONH is an important cause of severe visual disability; with an over-representation of Maori children and younger maternal age.

Congenital abnormalities of the optic nerve: from gene mutation to clinical expression

Optic nerve malformations are common causes of congenital blindness and are recognized with increasing prevalence. The importance of identifying these malformations lies not only in determining the cause and level of visual impairment, but also in looking for associated treatable or life threatening systemic conditions. A number of genetic mutations have been identified in the development of optic disc anomalies, such as ones in PAX2 or PAX6. Recent advances in genetic testing like array comparative genomic hybridization allow the detection of microdeletions that were previously difficult or impossible to identify.

Classifying infants and toddlers with developmental vulnerability: who is most likely to receive early intervention?

BACKGROUND

Infants and toddlers with developmental difficulties represent a heterogeneous group who often receives early intervention (EI). Notable population heterogeneity exists and complicates unmet need and effectiveness research. However, a mix of relatively homogeneous clinically policy relevant 'subgroups' may create the apparent heterogeneity. To date, methodological challenges have impeded identifying these potential groups and their policy-relevance.

METHODS

From the 2005-2006 National Survey of Children with Special Health Care Needs, we derived a sample (n = 965) of infants and toddlers with parent-reported developmental difficulties. We used latent class analysis (LCA) to identify subgroups of developmental vulnerability based upon functional, social and biological characteristics that would make children eligible for EI. Mixture modelling estimated the likelihood of each subgroup receiving parent-reported EI, controlling for race/ethnicity, child's age, and state of residence.

RESULTS

LCA identified four distinct subgroups of developmental vulnerability: developmental disability (Group 1), mild developmental delay (Group 2), socially at risk with behaviour problems (Group 3), and socially at risk with functional vision difficulties (Group 4). Black, non-Hispanic children are significantly more likely than their white counterparts to be in Group 3 (β = 1.52, P = 0.001) or group 4 (β = 1.83, P < 0.001). Compared with children with a mild developmental delay (Group 2), children in group 1 (β = -0.61, P < 0.001), group 3 (β = -0.47, P = 0.001) and group 4 (β = -0.38, P = 0.009) are significantly less likely to receive EI.

CONCLUSIONS

Racial and ethnic differences exist with regard to membership in developmental vulnerability subgroups. Observed inconsistencies in access to EI suggest the need for improved surveillance, referral and outreach.

Absence of age-related optic disk changes in young children with optic nerve hypoplasia

PURPOSE

To determine whether the ratio of optic disk diameter to disk-to-macula distance (DD/DM) in children with optic nerve hypoplasia (ONH) changes over time.

PATIENTS AND METHODS

Fifteen subjects (29 eyes) enrolled in a prospective registry study on ONH had fundus photography performed under the age of 24 months and again at 60 months. Using the ratio of the DD/DM method, the relative size of the optic disk was assessed twice for each photo by one masked expert examiner to determine whether any change in relative disk size occurred over time.

RESULTS

There was no change in relative optic disk size between initial and final fundus photographs. The average (± SD) age at the time of initial and final fundus photography was, respectively, 11.6 ± 5.2 months and 60.6 ± 1.3 months. Strong concordance was noted between the average DD/DM of the initial and the final photographs (ρ=0.939; 95% CI: 0.893, 0.981). There was negligible difference between the individual time point measurements (-0.011 ± 0.03) (95% LOA: -0.07, 0.04).

CONCLUSION

There were no clinically significant changes in relative optic disk size over time in children with ONH; thus, DD/DM measurements need not be adjusted by age beyond 1 year in children with this disorder.