Ocular Manifestations in Fetal Alcohol Syndrome

Optic Nerve Hypoplasia - Case Report

The case report of a young myope (born in 1997) who was diagnosed with bilateral concentric narrowing of the visual field to 15-20 degrees in 2021 is presented. On eye fundus, the findings were normal with central excavation c/d=0.5 and 0.4, respectively. OCT showed loss of retinal nerve fiber layer - in both vertical quadrants, including a reduction in the ganglion cell complex. Electrophysiological examination (PERG) showed normal retinal responses. Visual evoked responses (PVEP) after stimulation squared a 1 degree decrease in amplitudes, with no prolongation of P100 latency. When stimulated with 15-minute squares, responses were normal (see Supplementary Figure). Magnetic resonance imaging of the brain showed a narrowing of the chiasm. In conclusion, optic chiasm hypoplasia may not always have distinct morphological and functional manifestations. In addition to imaging methods, electrophysiological examination of the visual analyser was of great help for its verification.

Tracing the influence of prenatal risk factors on the offspring retina: Focus on development and putative long-term consequences

BACKGROUND

Pregnancy represents a window of vulnerability to fetal development. Disruptions in the prenatal environment during this crucial period can increase the risk of the offspring developing diseases over the course of their lifetime. The central nervous system (CNS) has been shown to be particularly susceptible to changes during crucial developmental windows. To date, research focused on disruptions in the development of the CNS has predominantly centred on the brain, revealing a correlation between exposure to prenatal risk factors and the onset of neuropsychiatric disorders. Nevertheless, some studies indicate that the retina, which is part of the CNS, is also vulnerable to in utero alterations during pregnancy. Such changes may affect neuronal, glial and vascular components of the retina, compromising retinal structure and function and possibly impairing visual function.

METHODS

A search in the PubMed database was performed, and any literature concerning prenatal risk factors (drugs, diabetes, unbalanced diet, infection, glucocorticoids) affecting the offspring retina were included.

RESULTS

This review collects evidence on the cellular, structural and functional changes occurring in the retina triggered by maternal risk factors during pregnancy. We highlight the adverse impact on retinal development and its long-lasting effects, providing a critical analysis of the current knowledge while underlining areas for future research.

CONCLUSIONS

Appropriate recognition of the prenatal risk factors that negatively impact the developing retina may provide critical clues for the design of preventive strategies and for early therapeutic intervention that could change retinal pathology in the progeny.

Vision outcomes in children with fetal alcohol spectrum disorders

BACKGROUND

Previous studies demonstrated that children with Fetal Alcohol Spectrum Disorders (FASD) are more likely to have vision impairments. However, existing human clinical and epidemiological investigations are few and include limited sample sizes. This study aimed to explore the association between ophthalmologic abnormalities and FASD in a sample of 5-7 year old children in the general population.

METHODS

This was a cross-sectional study nested in a larger study intended to estimate the prevalence of FASD in San Diego, California, conducted between 2012 and 2014. Prenatal exposure to alcohol, dysmorphology examinations, and a neurobehavioral testing battery were collected for each child and an FASD diagnosis was assigned. Parents of participating children were asked to release their child's vision screening or diagnostic records.

RESULTS

Vision records were obtained for 424 participants in the larger prevalence study. Of these, 53 children were classified as having FASD. A statistically significant association was found between FASD and a diagnosis of strabismus; 5/42 (11.9%) of children who were classified as having FASD had strabismus compared to 6/290 (2.1%) of children who were not classified as having FASD (p = .01). All five cases of strabismus in the FASD group occurred in 19 children classified as having partial fetal alcohol syndrome (pFAS). No association was found between FASD and vision impairment (p = .23), refractive errors (p = .66), glasses/contact lens prescription (p = .30), or having one or more ophthalmological abnormalities (p = .97).

CONCLUSIONS

An association between strabismus and FASD, specifically partial FAS, suggests that the effect of alcohol exposure on risk of strabismus must be severe enough to result in facial features consistent with FASD. This emphasizes the importance of vision screening in children with FASD.

miRNA Expression Analysis of the Hippocampus in a Vervet Monkey Model of Fetal Alcohol Spectrum Disorder Reveals a Potential Role in Global mRNA Downregulation

MicroRNAs (miRNAs) are short-length non-protein-coding RNA sequences that post-transcriptionally regulate gene expression in a broad range of cellular processes including neuro- development and have previously been implicated in fetal alcohol spectrum disorders (FASD). In this study, we use our vervet monkey model of FASD to follow up on a prior multivariate (developmental age × ethanol exposure) mRNA analysis (GSE173516) to explore the possibility that the global mRNA downregulation we observed in that study could be related to miRNA expression and function. We report here a predominance of upregulated and differentially expressed miRNAs. Further, the 24 most upregulated miRNAs were significantly correlated with their predicted targets (Target Scan 7.2). We then explored the relationship between these 24 miRNAs and the fold changes observed in their paired mRNA targets using two prediction platforms (Target Scan 7.2 and miRwalk 3.0). Compared to a list of non-differentially expressed miRNAs from our dataset, the 24 upregulated and differentially expressed miRNAs had a greater impact on the fold changes of their corresponding mRNA targets across both platforms. Taken together, this evidence raises the possibility that ethanol-induced upregulation of specific miRNAs might contribute functionally to the general downregulation of mRNAs observed by multiple investigators in response to prenatal alcohol exposure.

Vascular Contributions to the Neurobiological Effects of Prenatal Alcohol Exposure

Fetal alcohol spectrum disorders (FASD) are often characterized as a cluster of brain-based disabilities. Though cardiovascular effects of prenatal alcohol exposure (PAE) have been documented, the vascular deficits due to PAE are less understood, but may contribute substantially to the severity of neurobehavioral presentation and health outcomes in persons with FASD.

Methods

We conducted a systematic review of research articles curated in PubMed to assess the strength of the research on vascular effects of PAE. 40 pertinent papers were selected, covering studies in both human populations and animal models.

Results

Studies in human populations identified cardiac defects, and defects in vasculature, including increased tortuosity, defects in basement membranes, capillary basal hyperplasia, endarteritis, and disorganized and diminished cerebral vasculature due to PAE. Preclinical studies showed that PAE rapidly and persistently results in vasodilation of large afferent cerebral arteries, but to vasoconstriction of smaller cerebral arteries and microvasculature. Moreover, PAE continues to affect cerebral blood flow into middle-age. Human and animal studies also indicate that ocular vascular parameters may have diagnostic and predictive value. A number of intervening mechanisms were identified, including increased autophagy, inflammation and deficits in mitochondria. Studies in animals identified persistent changes in blood flow and vascular density associated with endocannabinoid, prostacyclin and nitric oxide signaling, as well as calcium mobilization.

Conclusion

Although the brain has been a particular focus of studies on PAE, the cardiovascular system is equally affected. Studies in human populations, though constrained by small sample sizes, did link pathology in major blood vessels and tissue vasculature, including brain vasculature, to PAE. Animal studies highlighted molecular mechanisms that may be useful therapeutic targets. Collectively, these studies suggest that vascular pathology is a possible contributing factor to neurobehavioral and health problems across a lifespan in persons with a diagnosis of FASD. Furthermore, ocular vasculature may serve as a biomarker for neurovascular health in FASD.

Molecular Markers in Maternal Blood Exosomes Allow Early Detection of Fetal Alcohol Spectrum Disorders

Prenatal alcohol exposure can cause developmental abnormalities (fetal alcohol spectrum disorders; FASD), including small eyes, face and brain, and neurobehavioral deficits. These cannot be detected early in pregnancy with available imaging techniques. Early diagnosis could facilitate development of therapeutic interventions. Banked human fetal brains and eyes at 9−22 weeks’ gestation were paired with maternal blood samples, analyzed for morphometry, protein, and RNA expression, and apoptotic signaling. Alcohol (EtOH)-exposed (maternal self-report) fetuses were compared with unexposed controls matched for fetal age, sex, and maternal race. Fetal brain-derived exosomes (FB-E) were isolated from maternal blood and analyzed for protein, RNA, and apoptotic markers. EtOH use by mothers, assessed by self-report, was associated with reduced fetal eye diameter, brain size, and markers of synaptogenesis. Brain caspase-3 activity was increased. The reduction in eye and brain sizes were highly correlated with amount of EtOH intake and caspase-3 activity. Levels of several biomarkers in FB-E, most strikingly myelin basic protein (MBP; r > 0.9), correlated highly with morphological abnormalities. Reduction in FB-E MBP levels was highly correlated with EtOH exposure (p < 1.0 × 10−10). Although the morphological features of FAS appear long before they can be detected by live imaging, FB-E in the mother’s blood may contain markers, particularly MBP, that predict FASD.

Antenatal and neonatal factors and morphology of the optic nerve head in the Northern Finland birth cohort

PURPOSE

The optic nerve head (ONH) is a part of the brain that can be evaluated through the transparent medium of the eye. The purpose of this study was to explore the possible correlations among the properties of the optic nerve head, maternal factors during pregnancy and neonatal parameters in a randomized sample of a birth cohort.

METHODS

The Northern Finland 1966 Birth Cohort has been prospectively monitored since their antenatal period. Data on pregnancy and neonatal period were collected during gestation and right after birth in 1966. A randomized sample of 3070 subjects underwent an ophthalmic assessment at the age of 46-48 years. The examination protocol included scanning laser ophthalmoscopy with the Heidelberg Retina Tomograph. The ophthalmological parameters assessed were the disc area and the neuroretinal rim volume of the ONH.

RESULTS

We found that chronic pulmonary disease of the mother (p = 0.007), the number of gestational weeks (p = 0.030) and the mother's highest measured systolic blood pressure (p = 0.035) during pregnancy had a statistically significant effect on the disc area. Smaller disc size was associated with pulmonary disease and early gestation. There was a significant difference in rim volume between genders (p < 0.001). Women had larger neuroretinal rim volumes compared to men.

CONCLUSION

In this population-based study, the vast majority of antenatal and neonatal factors showed no correlation with optic disc area or rim volume. Furthermore, even the factors with statistically significant correlation with ONH morphology had limited predictive value.

The FASD Eye Code: a complementary diagnostic tool in fetal alcohol spectrum disorders

Objective

To create an easy-to-use complementary ophthalmological tool to support a fetal alcohol spectrum disorder (FASD) diagnosis.

Methods and Analysis

The FASD Eye Code was derived from 37 children with FASD evaluated along with 65 healthy age-matched and sex-matched controls. Four ophthalmological categories, which are abnormalities commonly found in children with FASD, were ranked independently on a 4-point scale, with 1 reflecting normal finding and 4 a strong presence of an abnormality: visual acuity, refraction, strabismus/binocular function and ocular structural abnormalities. The tool was validated on 33 children with attention deficit/hyperactivity disorder (ADHD), 57 children born moderate-to-late premature (MLP) and 16 children with Silver-Russell syndrome (SRS). Among children with ADHD none was born prematurely or small for gestational age (SGA) or diagnosed with FASD. Among children born MLP none was SGA, had a diagnosis of ADHD or FASD, or a history of retinopathy of prematurity. Children with SRS were all born SGA, half were born preterm and none had FASD. Children with FASD were re-examined as young adults.

Results

An FASD Eye Code cut-off total score of ≥10 showed an area under the curve (AUC) of 0.78 (95% CI 0.69 to 0.87), with 94% specificity and 43% sensitivity, in discriminating between FASD and controls, MLP and ADHD, corresponding to a positive likelihood ratio (LR+) of 7.5. Between FASD and controls, an AUC of 0.87 (CI 0.80 to 0.95), with 100% specificity and 43% sensitivity, was found; between FASD and SRS, an AUC of 0.60 (CI 0.45 to 0.75) was found, with 88% specificity and 43% sensitivity. A cut-off score of≥9 showed a specificity of 98% and a sensitivity of 57% for FASD versus controls, corresponding to an LR+ of 36.9. Scores in individuals with FASD were stable into young adulthood.

Conclusion

The FASD Eye Code has the potential to serve as a complementary tool and help to strengthen an FASD diagnosis.

In Utero Exposure to Smoking and Alcohol, and Passive Smoking during Childhood: Effect on the Retinal Nerve Fibre Layer in Young Adulthood

PURPOSE

In utero exposure to cigarette smoke has been suggested to result in thinner retinal nerve fibre layer (RNFL). However, the potential cofounding effects of in utero alcohol exposure and passive smoking during childhood had not been considered. We explored RNFL thickness in young adults in relation to these early life factors.

METHODS

In 1989-1991, pregnant women completed questionnaires on their current smoking and alcohol drinking patterns. Following the birth of their offspring, information on household smokers was obtained between the 1- and 13-year follow-ups. At the 20-year follow-up, these offspring underwent an eye examination including optical coherence tomography imaging of the RNFL.

RESULTS

Participants (n = 1,287) were 19-22 years old at time of eye examination. Most participants (77%) had no in utero exposure to cigarette smoke; 1.3% were initially exposed but not after 18 weeks' gestation, while 21% had continual in utero smoking exposure. Half of the mothers never consumed alcohol or only consumed alcohol once during their pregnancies. After correcting for potential confounders, including in utero alcohel exposure and childhood passive smoking, participants who had continued in utero exposure to >10 cigarettes/day and ≤10 cigarettes/day had thinner RNFLs by 6.6 (95% confidence interval [CI] = 4.4-8.7) and 3.7 µm (95%[CI] = 2.3-5.5), respectively, than those with no exposure (p < .001). In utero alcohol exposure and childhood passive smoking were not significantly associated with RNFL thickness after accounting for in utero exposure to smoking.

CONCLUSIONS

In utero exposure to cigarette smoke is associated with thinner RFNL in young adulthood, independent of other early life environmental factors.

Alcohol and the Eye

In this article, we present a review of ocular conditions related to alcohol consumption. A search of the literature published from 1952 to March 2020 was performed. The titles and abstracts were screened and the eligible studies were selected. PubMed, ISI Web of Knowledge database, Scopus, Embase, and the Cochrane Library were searched. We categorized the relationship between alcohol intake and ocular conditions by the type of ocular exposure to alcohol. Accordingly, ocular findings following acute alcohol intoxication, optic neuropathy following methanol toxicity, congenital conditions related to maternal alcohol consumption, and ocular disease related to chronic alcoholism are discussed. The main feature of alcohol intoxication in the eye is abnormal eye movement. Acute optic neuropathy secondary to methyl alcohol consumption is a serious ocular disease with permanent vision loss or scotoma. Prenatal exposure to ethanol may end in fetal alcohol spectrum disease, where ocular findings are a constant component. The association between chronic alcohol consumption and increased risks of cataract, age-related macular degeneration, diabetic retinopathy, different types of optic neuropathy, impairment of visual quality, retinal vascular disease, and ocular surface disease has also been reported. Along with detrimental medical and social effects, the role of alcohol consumption in different ocular conditions should be considered, as alcohol-induced visual disturbances may contribute to the heavy burden of alcohol abuse on the healthcare system and overall quality of life.

A review of studies exploring fetal alcohol spectrum disorders through eye tracking measures

The widespread cognitive and cerebral consequences of prenatal alcohol exposure have been established during the last decades, through the exploration of fetal alcohol spectrum disorders (FASD) using neuropsychological and neuroscience tools. This research field has recently benefited from the emergence of innovative measures, among which eye tracking, allowing a precise measure of the eye movements indexing a large range of cognitive functions. We propose a comprehensive review, based on PRISMA guidelines, of the eye tracking studies performed in populations with FASD. Studies were selected from the PsycINFO, PubMed and Scopus databases, and were evaluated through a standardized methodological quality assessment. Studies were classified according to the eye tracking indexes recorded (saccade characteristics, initial fixation, number of fixations, dwell time, gaze pattern) and the process measured (perception, memory, executive functions). Eye tracking data showed that FASD are mostly associated with impaired ocular perceptive/motor abilities (i.e., altered eye movements, centrally for saccade initiation), lower accuracy as well as increased error rates in saccadic eye movements involving working memory abilities, and reduced inhibitory control on saccades. After identifying the main limitations presented by the reviewed studies, we propose guidelines for future research, underlining the need to increase the standardization of diagnosis and evaluation tools, and to improve the methodological quality of eye tracking measures.

Routine Orthoptic-led Paediatric Fundus Digital Imaging: Benefits to Patients and Healthcare System

Aims:

Dilated fundus examinations are a vital, yet time-consuming and sometimes distressing part of paediatric ophthalmology examinations. Limited resources, personnel and time can result in prolonged waiting time and increase risk from delayed diagnosis and treatment. Using a Nikon D80 TopCon TRC-NW6S non-mydriatic fundus camera (TopCon (GB) Ltd, Newbury), we aimed to demonstrate the safety and efficacy of orthoptic-led fundus digital imaging and the potential time and cost benefits to the healthcare system.

Methods:

We conducted a retrospective review of all digital fundus images taken over a six month period in 2012 (n = 616, age range 2.1–16.5 years, mean age 8.7 years).

Results:

Overall success rate for paediatric fundus digital imaging was 97%. Successful images were achieved in 87% of patients without the need for pupil dilation. Images were taken for a variety of clinical reasons. 45% of patients were discharged immediately, many with copies of photographs to facilitate follow-up with community optometrists.

Conclusions:

Orthoptic-led fundus digital imaging is an innovative, speedy, safe and efficient method of documenting fundal appearance, enabling serial documentation of stability/progression of ocular disease. It allows adequate examination of routine patients, freeing up time within busy clinics. Paediatric fundus digital imaging brings a potential positive cost benefit to healthcare systems under pressure, and facilitates skill development for allied health professionals.

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.

Differences in neural crest sensitivity to ethanol account for the infrequency of anterior segment defects in the eye compared with craniofacial anomalies in a zebrafish model of fetal alcohol syndrome

BACKGROUND

Ethanol (ETOH) exposure during pregnancy is associated with craniofacial and neurologic abnormalities, but infrequently disrupts the anterior segment of the eye. In these studies, we used zebrafish to investigate differences in the teratogenic effect of ETOH on craniofacial, periocular, and ocular neural crest.

METHODS

Zebrafish eye and neural crest development was analyzed by means of live imaging, TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assay, immunostaining, detection of reactive oxygen species, and in situ hybridization.

RESULTS

Our studies demonstrated that foxd3-positive neural crest cells in the periocular mesenchyme and developing eye were less sensitive to ETOH than sox10-positive craniofacial neural crest cells that form the pharyngeal arches and jaw. ETOH increased apoptosis in the retina, but did not affect survival of periocular and ocular neural crest cells. ETOH also did not increase reactive oxygen species within the eye. In contrast, ETOH increased ventral neural crest apoptosis and reactive oxygen species production in the facial mesenchyme. In the eye and craniofacial region, sod2 showed high levels of expression in the anterior segment and in the setting of Sod2 knockdown, low levels of ETOH decreased migration of foxd3-positive neural crest cells into the developing eye. However, ETOH had minimal effect on the periocular and ocular expression of transcription factors (pitx2 and foxc1) that regulate anterior segment development.

CONCLUSION

Neural crest cells contributing to the anterior segment of the eye exhibit increased ability to withstand ETOH-induced oxidative stress and apoptosis. These studies explain the rarity of anterior segment dysgenesis despite the frequent craniofacial abnormalities in fetal alcohol syndrome. Birth Defects Research 109:1212-1227, 2017. © 2017 Wiley Periodicals, Inc.

Dopamine attenuates ethanol-induced neuroapoptosis in the developing rat retina via the cAMP/PKA pathway

Apoptosis has been identified as the primary cause of fetal alcohol spectrum disorder (FASD), and the development of methods to prevent and treat FASD have been based on the mechanisms of alcohol-induced apoptosis. The present study aimed to explore the effects of dopamine on alcohol-induced neuronal apoptosis using whole-mount cultures of rat retinas (postnatal day 7). Retinas were initially incubated with ethanol (100, 200 or 500 mM), and in subsequent analyses retinas were co-incubated with ethanol (200 mM) and dopamine (10 µM). In addition, several antagonists and inhibitors were used, including a D1 dopamine receptor (D1R) antagonist (SCH23390; 10 µM), a D2R antagonist (raclopride; 40 µM), an adenosine A2A receptor (AA2AR) antagonist (SCH58261; 100 nM), an adenylyl cyclase (AC) inhibitor (SQ22536; 100 µM) and a PKA inhibitor (H-89; 1 µM). The results demonstrated that exposure increased neuroapoptosis in the retinal ganglion cell layer (GCL) in a dose-dependent manner. Dopamine treatment significantly attenuated ethanol-induced neuronal apoptosis. D1R, D2R and AA2AR antagonists partially inhibited the protective effects of dopamine against ethanol-induced apoptosis; similar results were observed with AC and PKA inhibitor treatments. In summary, the present study demonstrated that dopamine treatment may be able to attenuate alcohol-induced neuroapoptosis in the developing rat retina by activating D1R, D2R and AA2AR, and by upregulating cyclic AMP/protein kinase A signaling.

Prenatal ethanol exposure in mice phenocopies Cdon mutation by impeding Shh function in the etiology of optic nerve hypoplasia

Septo-optic dysplasia (SOD) is a congenital disorder characterized by optic nerve, pituitary and midline brain malformations. The clinical presentation of SOD is highly variable with a poorly understood etiology. The majority of SOD cases are sporadic, but in rare instances inherited mutations have been identified in a small number of transcription factors, some of which regulate the expression of Sonic hedgehog (Shh) during mouse forebrain development. SOD is also associated with young maternal age, suggesting that environmental factors, including alcohol consumption at early stages of pregnancy, might increase the risk of developing this condition. Here, we address the hypothesis that SOD is a multifactorial disorder stemming from interactions between mutations in Shh pathway genes and prenatal ethanol exposure. Mouse embryos with mutations in the Shh co-receptor, Cdon, were treated in utero with ethanol or saline at embryonic day 8 (E8.0) and evaluated for optic nerve hypoplasia (ONH), a prominent feature of SOD. We show that both Cdon^-/- mutation and prenatal ethanol exposure independently cause ONH through a similar pathogenic mechanism that involves selective inhibition of Shh signaling in retinal progenitor cells, resulting in their premature cell-cycle arrest, precocious differentiation and failure to properly extend axons to the optic nerve. The ONH phenotype was not exacerbated in Cdon^-/- embryos treated with ethanol, suggesting that an intact Shh signaling pathway is required for ethanol to exert its teratogenic effects. These results support a model whereby mutations in Cdon and prenatal ethanol exposure increase SOD risk through spatiotemporal perturbations in Shh signaling activity.

Comorbidity of fetal alcohol spectrum disorder: a systematic review and meta-analysis

BACKGROUND

Fetal alcohol spectrum disorder (FASD) is related to many comorbidities because of the permanent effects of prenatal alcohol exposure on the fetus. We aimed to identify the comorbid conditions that co-occur in individuals with FASD and estimate the pooled prevalence of comorbid conditions occurring in individuals with fetal alcohol syndrome (FAS).

METHODS

We did a systematic literature search of studies reporting on the comorbidity and cause of death in individuals with FASD using multiple electronic bibliographic databases, searching for studies published up to July, 2012. We included original research published in a peer-reviewed journal in the English language. We used the following criteria for determining study quality: use of an established FASD diagnostic guideline, study setting, method of data collection, and sample size. All comorbid disease conditions were coded according to the International Classification of Diseases, tenth revision (ICD-10). To estimate the pooled prevalence of comorbid conditions found to co-occur in individuals with FAS, we did meta-analyses assuming a random-effects model.

FINDINGS

Of 5068 studies found, 127 met eligibility criteria for data extraction. From those studies, we identified 428 comorbid conditions co-occurring in individuals with FASD, spanning across 18 of 22 chapters of the ICD-10. The most prevalent disease conditions were within the sections of congenital malformations, deformities, and chromosomal abnormalities, and mental and behavioural disorders. 33 studies reported data for frequency in a total of 1728 participants with FAS. The five comorbid conditions with the highest pooled prevalence (between 50% and 91%) included abnormal results of function studies of peripheral nervous system and special senses, conduct disorder, receptive language disorder, chronic serous otitis media, and expressive language disorder.

INTERPRETATION

The high prevalence of comorbid conditions in individuals with FASD highlights the importance of assessing prenatal alcohol exposure as a substantial clinical risk factor for comorbidity. The harmful effects of alcohol on a developing fetus represent many cases of preventable disability, and thus, alcohol use during pregnancy should be recognised as a public health problem globally.

FUNDING

Public Health Agency of Canada.

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.

Prenatal determinants of optic nerve hypoplasia: review of suggested correlates and future focus

Optic nerve hypoplasia (ONH), a congenital malformation characterized by an underdeveloped optic nerve, is a seemingly epidemic cause of childhood blindness and visual impairment with associated lifelong morbidity. Although the prenatal determinants of ONH are unknown, early case reports have led to a longstanding speculation that risky health behaviors (e.g., prenatal use of recreational drugs, alcohol) are a likely culprit. There has yet to be a systematic review of the epidemiology of ONH to assess the common prenatal features that may help focus research efforts in the identification of likely prenatal correlates. A review of the past 50 years of epidemiologic research was conducted to examine the prenatal features linked with ONH and provide direction for future research. There are select prominent prenatal features associated with ONH: young maternal age and primiparity. Commonly implicated prenatal exposures (recreational or pharmaceutical drugs, viral infection, etc.) were rare or uncommon in large cohort studies of ONH and therefore unlikely to be major contributors to ONH. Familial cases and gene mutations are rare. The preponderance of young mothers and primiparity among cases of ONH is striking, although the significance is unclear. Recent research suggests a potential role for prenatal nutrition, weight gain, and factors of deprivation. With the rapidly increasing prevalence of ONH, future research should focus on investigating the relevance of young maternal age and primiparity and exploring the recently suggested etiologic correlates in epidemic clusters of ONH.

Incidence and associated endocrine and neurologic abnormalities of optic nerve hypoplasia

IMPORTANCE

Optic nerve hypoplasia (ONH) is an increasingly recognized cause of congenital blindness in children; however, there is significant discord regarding its incidence and the rate of associated conditions.

OBJECTIVE

To determine the incidence of ONH and the rate of associated endocrine, neurologic, and developmental abnormalities among a population-based cohort of pediatric patients.

DESIGN

Retrospective, population-based study.

SETTING

Olmsted County, Minnesota (95.7% white in 1990).

PARTICIPANTS

All pediatric residents (aged <19 years) of Olmstead County, diagnosed as having ONH from January 1, 1984, through December 31, 2008.

MAIN OUTCOMES AND MEASURES

Incidence of ONH and the rate of associated endocrine, neurologic, and developmental abnormalities.

RESULTS

Optic nerve hypoplasia was diagnosed in 19 pediatric patients during the 25-year study period, for an annual incidence of 2.4 (95% CI, 1.2-3.5) per 100,000 residents younger than 19 years or 1 in 2287 live births. The mean age at diagnosis was 2.1 years, and 10 (53%) patients were male. Commonly associated perinatal conditions included primiparity in 8 patients (42%), premature birth in 6 (32%), and maternal diabetes mellitus in 3 (16%). Of the 19 study patients, 16 (84%) had bilateral involvement at initial examination, 9 (47%) had decreased visual acuity, 8 (42%) had strabismus, and 5 (26%) had nystagmus. Systemic conditions included developmental delay in 12 (63%), neurologic deficits in 10 (53%), and endocrine dysfunction in 5 (26%).

CONCLUSIONS AND RELEVANCE

This population-based study demonstrated an incidence of ONH of 1 in 2287 live births. More than half of the patients had developmental and neurologic deficits, and one-fourth had a diagnosis of endocrine dysfunction.

Optic nerve hypoplasia syndrome: a review of the epidemiology and clinical associations

OPINION STATEMENT

BACKGROUND

Optic nerve hypoplasia (ONH) has developed into a leading cause of congenital blindness. The frequently associated features of hypopituitarism and absent septum pellucidum were felt to have embryonic linkage as "septo-optic dysplasia" or "de Morsier's syndrome." More recent studies have suggested these associations are independent of one another. This review provides an assessment of the historical and recent evidence linking neuroradiologic, endocrinologic and developmental morbidity in patients with ONH. The prenatal risk factors, heritability, and genetic mutations associated with ONH are described.

RESULTS

Recognition of the critical association of ONH with hypopituitarism should be attributed to William Hoyt, not Georges de Morsier. De Morsier never described a case of ONH or recognized its association with hypopituitarism or missing septum pellucidum. Hypopituitarism is caused by hypothalamic dysfunction. This, and other more recently identified associations with ONH, such as developmental delay and autism, are independent of septum pellucidum development. Other common neuroradiographic associations such as corpus callosum hypoplasia, gyrus dysplasia, and cortical heterotopia may have prognostic significance. The predominant prenatal risk factors for ONH are primiparity and young maternal age. Presumed risk factors such as prenatal exposure to drugs and alcohol are not supported by scrutiny of the literature. Heritability and identified gene mutations in cases of ONH are rare.

CONCLUSION

Children with ONH require monitoring for many systemic, developmental, and even life-threatening problems independent of the severity of ONH and presence of brain malformations including abnormalities of the septum pellucidum. "Septo-optic dysplasia" and "de Morsier's syndrome" are historically inaccurate and clinically misleading terms.

Reappraisal of the optic nerve hypoplasia syndrome

BACKGROUND

Optic nerve hypoplasia (ONH) has been described as an increasingly prevalent cause of congenital blindness. Its association with hypopituitarism and absent septum pellucidum has been recognized for more than 40 years as "septo-optic dysplasia" or "de Morsier syndrome." More recent studies have suggested that these associations are independent of one another. This review was designed to assess the historical and recent evidence for associations of neuroradiologic, endocrinologic, and developmental problems in patients with ONH.

EVIDENCE ACQUISITION

Historical and contemporary literature review.

RESULTS

The medical literature does not support the notion that Georges de Morsier ever described a case of ONH or recognized its association with hypopituitarism or missing septum pellucidum. Recognition of the critical association of ONH with hypopituitarism should be attributed to William Hoyt. Hypopituitarism and other more recently identified associations with ONH, such as developmental delay, hypothalamic dysfunction, and autism, are independent of septum pellucidum development. Other common neuroradiographic associations, such as corpus callosum hypoplasia, gyrus dysplasia, and cortical heterotopia, may have prognostic significance.

CONCLUSIONS

Children with ONH need to be monitored for many systemic, developmental, and even life-threatening problems independent of the status of the septum pellucidum. "Septo-optic dysplasia" and "de Morsier syndrome" are historically inaccurate and clinically misleading terms that should be abandoned.

Ethanol-induced face-brain dysmorphology patterns are correlative and exposure-stage dependent

Prenatal ethanol exposure is the leading preventable cause of congenital mental disability. Whereas a diagnosis of fetal alcohol syndrome (FAS) requires identification of a specific pattern of craniofacial dysmorphology, most individuals with behavioral and neurological sequelae of heavy prenatal ethanol exposure do not exhibit these defining facial characteristics. Here, a novel integration of MRI and dense surface modeling-based shape analysis was applied to characterize concurrent face-brain phenotypes in C57Bl/6J fetuses exposed to ethanol on gestational day (GD)7 or GD8.5. The facial phenotype resulting from ethanol exposure depended upon stage of insult and was predictive of unique patterns of corresponding brain abnormalities. Ethanol exposure on GD7 produced a constellation of dysmorphic facial features characteristic of human FAS, including severe midfacial hypoplasia, shortening of the palpebral fissures, an elongated upper lip, and deficient philtrum. In contrast, ethanol exposure on GD8.5 caused mild midfacial hypoplasia and palpebral fissure shortening, a shortened upper lip, and a preserved philtrum. These distinct, stage-specific facial phenotypes were associated with unique volumetric and shape abnormalities of the septal region, pituitary, and olfactory bulbs. By demonstrating that early prenatal ethanol exposure can cause more than one temporally-specific pattern of defects, these findings illustrate the need for an expansion of current diagnostic criteria to better capture the full range of facial and brain dysmorphology in fetal alcohol spectrum disorders.

Optic nerve hypoplasia in North America: a re-appraisal of perinatal risk factors

PURPOSE

The purpose of this study is to describe and clarify the birth and prenatal characteristics of a large cohort of children with optic nerve hypoplasia.

METHODS

This is a descriptive report of 204 patients aged

RESULTS

Birth characteristics were unremarkable for birthweight and gestation, but significant for increased frequency of caesarean delivery and fetal and neonatal complications. Young maternal age and primaparity were dominating maternal features. Preterm labour, gestational vaginal bleeding, low maternal weight gain and weight loss during pregnancy were prevalent.

CONCLUSIONS

These findings confirm young maternal age and primaparity as associated risk factors, challenge many other suggested factors such as alcohol and drug abuse, and introduce potentially significant prenatal characteristics such as maternal weight loss and early gestational vaginal bleeding as aetiological correlates.

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Key Words

• aetiology
• de morsier syndrome
• optic nerve hypoplasia
• perinatal
• prenatal
• septo-optic dysplasia

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MESH Headings

• Birth Weight
• Child, Preschool
• Eye Abnormalities/epidemiology
• Female
• Gestational Age
• Humans
• Infant
• Infant, Newborn
• Infant, Premature
• Male
• Maternal Age
• North America/epidemiology
• Optic Nerve/abnormalities
• Parity
• Pregnancy
• Prospective Studies
• Registries/statistics & numerical data
• Risk Factors
• Sweden/epidemiology

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Grants

• M01 RR000043-44 NCRR NIH HHS
• UL1 RR031986 NCRR NIH HHS
• M01 RR00043 NCRR NIH HHS
• UL1 RR031986-01 NCRR NIH HHS
• M01 RR000043 NCRR NIH HHS

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Affiliation(s)

Pamela Garcia-Filion The Vision Center at Childrens Hospital Los Angeles, and Department of Ophthalmology, Keck School of Medicine, University of Southern California, Los Angeles, California 90027, USA.
Cassandra Fink
Mitchell E Geffner
Mark Borchert

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In-utero exposure to smoking, alcohol, coffee, and tea and risk of strabismus

In a prospective, population-based cohort study, the authors investigated the effect of in-utero exposure to maternal smoking and consumption of alcohol, coffee, and tea on the risk of strabismus. They reviewed medical records for children in the Danish National Birth Cohort identified through national registers as possibly having strabismus. Relative risk estimates were adjusted for year of birth, social class, maternal smoking, maternal age at birth, and maternal coffee and tea consumption. The authors identified 1,321 cases of strabismus in a cohort of 96,842 Danish children born between 1996 and 2003. Maternal smoking was associated with a significantly elevated risk of strabismus in the child, increasing with number of cigarettes smoked per day (<5 cigarettes/day: relative risk (RR) = 0.95, 95% confidence interval (CI): 0.80, 1.14; 5-<10 cigarettes/day: RR = 1.38, 95% CI: 1.12, 1.70; > or =10 cigarettes/day: RR = 1.90, 95% CI: 1.57, 2.30). Nicotine replacement therapy was not associated with strabismus risk (RR = 1.22, 95% CI: 0.92, 1.61). Light maternal alcohol consumption was inversely associated with strabismus risk, whereas maternal coffee and tea drinking were not associated with strabismus risk. In conclusion, smoking during pregnancy is associated with an increased risk of strabismus in the offspring. Conversely, light alcohol consumption is associated with decreased risk.

Eye malformations in children with heavy alcohol exposure in utero

OBJECTIVE

To determine whether children who do not develop fetal alcohol syndrome (FAS) despite heavy alcohol exposure are at risk for eye abnormalities.

STUDY DESIGN

We screened 9628 pregnant women and identified 101 women who were drinking >/= 2 oz of absolute alcohol per day and 101 nondrinking control women. We followed 43 exposed and 55 control offspring between age 4 and 9 years, performing masked standardized ophthalomologic examinations.

RESULTS

The groups did not differ in their rates of impaired visual acuity, refractory errors, ptosis, epicanthal folds, or short palpebral fissures. Biomicroscopy examination was normal in all exposed subjects; cataracts were detected in 2 control subjects (4%) but in no exposed subjects. Arterial tortuosity was seen in 7 exposed subjects (16%) and in 8 control subjects (15%). Optic nerve hypoplasia was not detected in any subject.

CONCLUSIONS

Previous research has found that children with FAS have a high incidence of serious ophthalmologic defects; our data indicate that the risk is limited to children with FAS and does not extend to children exposed to high levels of alcohol prenatally who do not develop FAS. Eye examinations are unlikely to clarify the diagnosis in children suspected of having alcohol-related damage.

Value of the Heidelberg Retinal Tomograph in optic nerve hypoplasia

PURPOSE

A case of optic nerve hypoplasia (ONH) is reported to demonstrate the value of the Heidelberg Retinal Tomograph II (HRT) in assisting with the diagnosis.

CASE REPORT

An 8-year-old black male was referred to our clinic for evaluation of right esotropia and presumed amblyopia. Best-corrected visual acuities were 20/60 OD (right eye) and 20/25 OS (left eye). Cover test showed constant right esotropia, measuring 10 at distance and 16 at near. A smaller optic nerve head was detected OD with absence of the double ring sign. The findings of HRT were consistent with a diagnosis of unilateral ONH, with a disc area of 1.545 mm OD vs. 2.527 mm OS.

DISCUSSION

The clinical features, management, and associations of ONH are discussed.

CONCLUSION

HRT is a useful tool to assist in diagnosis of ONH by physically measuring the optic nerve.