Prevalence and prenatal diagnosis of congenital eye anomalies: A population-based study

OBJECTIVE

To estimate the prevalence and trend of congenital eye anomalies (CEAs) and the rate of prenatal diagnosis over a 10-year period.

DESIGN

Retrospective population-based registry study.

SETTING

All maternity units in Paris, France, from 2010 to 2020.

POPULATION

A cohort of 115 cases of CEA detected among all live births or stillbirths, after 22 weeks of gestation, and terminations of pregnancy.

METHODS

The total prevalence of CEAs and prevalence of each specific CEA were calculated using 95% Poisson exact confidence intervals.

MAIN OUTCOME MEASURES

The total prevalence of CEAs and the proportion of prenatal diagnosis of CEAs, and their evolution.

RESULTS

The prevalence of CEAs was 4.1 (95% CI 3.4-5.0) cases, ranging between 3.1 and 5.7 cases, per 10 000 births. CEAs were prenatally diagnosed in 23.5% of cases. CEAs were bilateral in 51 cases (44.3%), unilateral in 43 cases (37.4%) and missing or unknown in 21 cases (18.3%). Of those with CEAs, 20.9% had genetic anomalies and 53.0% had at least one other extraocular anomaly. When detected prenatally, CEAs were bilateral in 15 cases (55.6%), unilateral in eight cases (29.6%) and missing in the four remaining cases. The prenatal diagnosis rate of CEAs associated with genetic anomalies, CEA cases with at least one other malformation and isolated CEA cases were 29.2%, 26.2% and 13.3%, respectively.

CONCLUSIONS

In total, 115 cases of CEAs were observed during the study period, representing a total prevalence of 4.1 cases per 10 000 births. The overall prenatal detection rate of CEAs in our population was 23.5%, which dropped to 13.3% for isolated cases of CEAs.

Fetal eye ultrasound: Normal anatomy, abnormal findings, and clinical impact

Until now, ultrasound examination of the fetal eyes has not played an important role in prenatal diagnosis. National and international guidelines are generally confined to documentation of the presence of the orbits and the lenses. However, in recent years, with the advent of high-resolution ultrasound technology and increasing knowledge of prenatal medicine and genetics, careful examination of the fetal eye has enabled the detection of many ocular malformations before birth. This article provides an overview of the anatomy related to the development of the fetal eye and covers the following conditions: hypertelorism, hypotelorism, exophthalmos, microphthalmos, coloboma, cataract, persistent hyperplastic primary vitreous, retinal detachment, dacryocystocele, and septooptic dysplasia, etc. It is designed to illustrate the spectrum of ocular malformations and their appearance on prenatal ultrasound and to discuss their clinical impact and association with various syndromes.

Prenatal and Postnatal Ocular Abnormalities Following Congenital Zika Virus Infections: A Systematic Review

OBJECTIVE

To assess fetal and neonatal eyes abnormalities and their progression during the last ZIKV outbreak and summarize learned lessons.

METHODS

A systematic review and meta-analysis was conducted by a team of obstetricians and ophthalmologists.

RESULTS

Studies reporting ocular abnormalities during the prenatal (n = 5) and postnatal (n = 24) periods were included in the analysis. In the prenatal period, the most common ocular findings were intraocular calcification cases (4/6, 66.6%) and microphthalmia (3/6, 50%). Postnatal ocular abnormalities of congenital ZIKV infection were described after birth in 479 cases. Among them microphthalmia was reported in 13 cases (13/479, 2.7%). Posterior segment (retina and optic nerve) was the most affected structure, consisting of pigmentary changes (229/479, 47.8%), macular chorioretinal atrophy (216/479, 45%), optic nerve atrophy (181/479, 37.8%), increased cup-to-disk ratio (190/479, 39.6.%), optic nerve hypoplasia (93/479,19.4%), vascular changes (26/479, 5.4%), and retinal coloboma (20/479, 4.1%). The anterior segment was involved in 4.6% (22/479) of cases, including cataract (9/479, 1.8%), lens subluxation (1/479, 0.2%), iris coloboma (5/479, 1%), and congenital glaucoma (7/479, 1.4%). These ocular anomalies were isolated in one case (1/479, 0.2%) and multiple anomalies were found in the other cases. Long-term visual disorders have been described, with no possible improvement and even a worsening of some of the ocular anomalies previously observed. No reactivation of ocular lesions was observed.

CONCLUSION

This review highlights the severe ocular abnormalities associated with congenital ZIKV infections. The importance of multidisciplinary communication between the obstetrician, the maternal-fetal medicine specialist, and the ophthalmologist is emphasized.

PROTOCOL REGISTRATION

This systematic review was registered with the International Prospective Register of Systematic Reviews (PROSPERO), registration440 188.

Prenatal Array-CGH Detection of 3q26.32q26.33 Interstitial Deletion Encompassing the SOX2 Gene: Ultrasound, Pathological, and Cytogenetic Findings

Background: SOX2 disorders are associated with anophthalmia-esophageal-genital syndrome or microphthalmia, syndromic 3 (MCOPS3- # 206900). Case Report: We describe a third fetal case with a de novo 3q26.32q26.33 deletion extending for 4.31 Mb, detected in a 15-week fetus. After legal interruption of pregnancy, at autopsy, the fetus presented bilateral microphthalmia, right cleft lip and palate, bilateral cerebral ventriculomegaly and dilated third ventricle, microcystic left lung, and intestinal malrotation. Histologically, the left lung showed congenital pulmonary airway malformation (CPAM) type 2. Retinal dysplasia was found in both eyes. Discussion/Conclusion: The human SOX2 gene (OMIM #184429) is located on chromosome 3 at position q26.3-27 and encodes a transcription factor involved in the development of the central and peripheral nervous systems, retina, and lung. In our case, the combination of cerebral, retinal, and pulmonary anomalies, not previously described, are consistent with SOX2 haploinsufficiency due to chromosomal deletion.

Ultrasonographic monitoring of fetal eye growth parameters throughout gestation in the common marmoset (Callithrix jacchus)

The common marmoset (Callithrix jacchus) is considered an ideal species for developing genetically modified nonhuman primates (NHP) models of human disease, particularly eye disease. They have been proposed as a suitable bridge between rodents and other NHP models due to their similar ophthalmological features to humans. Prenatal ultrasonography is an accurate and reliable diagnostic tool for monitoring fetal development and congenital malformation. We monitored fetal eye growth and development using noninvasive ultrasonography in 40 heads of clinically normal fetuses during pregnancy to establish the criteria for studying congenital eye anomalies in marmosets. The coronal, sagittal, and transverse planes were useful to identify the facial structures for any associated abnormalities. For orbital measurements, biorbital distance (BOD), ocular diameter (OD), interorbital distance (IOD), and total axial length (TAL) were measured in the transverse plane and carefully identified for intraorbital structures. As a result, high correlations were observed between delivery-based gestational age (GA) and biparietal diameter (BPD), BOD, OD, and TAL. The correlation assessments based on BOD provide more reliable results for monitoring eye growth and development in normal marmosets than any other parameters since BOD has the highest correlation coefficient according to both delivery-based GA and BPD among ocular measurements. In conclusion, orbital measurements by prenatal ultrasonography provide reliable indicators of marmoset eye growth, and it could offer early diagnostic criteria to facilitate the development of eye disease models and novel therapies such as genome editing technologies in marmosets.

Refractive development I: Biometric changes during emmetropisation

PURPOSE

Although there are many reports on ocular growth, these data are often fragmented into separate parameters or for limited age ranges. This work intends to create an overview of normal eye growth (i.e., in absence of myopisation) for the period before birth until 18 years of age.

METHODS

The data for this analysis were taken from a search of six literature databases using keywords such as "[Parameter] & [age group]", with [Parameter] the ocular parameter under study and [age group] an indication of age. This yielded 34,409 references that, after screening of title, abstract and text, left 294 references with usable data. Where possible, additional parameters were calculated, such as the Bennett crystalline lens power, whole eye power and axial power.

RESULTS

There were 3422 average values for 17 parameters, calculated over a combined total of 679,398 individually measured or calculated values. The age-related change in refractive error was best fitted by a sum of four exponentials (r²  = 0.58), while all other biometric parameters could be fitted well by a sum of two exponentials and a linear term ('bi-exponential function'; r² range: 0.64-0.99). The first exponential of the bi-exponential fits typically reached 95% of its end value before 18 months, suggesting that these reached genetically pre-programmed passive growth. The second exponentials reached this point between 4 years of age for the anterior curvature and well past adulthood for most lenticular dimensions, suggesting that this part represents the active control underlying emmetropisation. The ocular components each have different growth rates, but growth rate changes occur simultaneously at first and then act independently after birth.

CONCLUSIONS

Most biometric parameters grow according to a bi-exponential pattern associated with passive and actively modulated eye growth. This may form an interesting reference to understand myopisation.

The growth and shape of the eyeball and crystalline lens in utero documented by fetal MR imaging

Purpose

To study the growth model, shape, and developmental relationship of lens and eyeball, we used two-dimensional Magnetic Resonance (MR) imaging to investigate gestationally age-related changes in the selected ocular parameters in vivo.

Materials and methods

We retrospectively reviewed the MR images from 126 fetuses ranging from 21 to 39 weeks' gestation. Ocular parameters on MR imaging of transverse plane were measured including lens diameter (LD), anteroposterior lens diameter (APLD), lens surface area (LS), globe diameter (GD), anteroposterior globe diameter (APGD), globe surface area (GS). The growth model of each biometric against gestational age (GA), aspect ratio of lens and globe (LD/APLD and GD/APGD), and growing relationship between the ratio of lens and globe surface area (LS/GS) were studied by statistical analysis.

Results

The growth model of most biometry for gestational age is logarithmic, except for the diameter of the ocular globe (GD and APGD) showing a quadratic growth pattern. Our study showed that the lens was consistently larger in the transverse than the anteroposterior diameters during 21-39 weeks(P < 0.001). Besides, the ratio of surface area (LS/GS) was not significantly changing with GA(P = 0.4908), while the increase of LS was significantly accorded with that of GS(P < 0.001).

Conclusion

The lens shape throughout fetal life may take part in the process, shape changing from vertical ellipsoid, spherical to transversal ellipsoid, based on the logarithmically increased ratio of lens transverse and anteroposterior diameters. In the meanwhile, the aspect ratio of eyeball in late fetal life may imply a gradually spherical shape during gestation. Nomogram data from this study may provide appropriate information about morphological changes in the fetal lens and the synchronous relationship between lens and eyeball.

Recurrent Fetal Anophthalmia Caused by retinoids acid gene 6 mutations: Correlation between prenatal ultrasonography, magnetic resonance imaging, and pathology

OBJECTIVE

Anophthalmia is an extreme form on the spectrum of anophthalmia-microphthalmia (A/M) syndrome. Most articles define fetal microphthalmia by an ocular diameter (OD) less than fifth percentile. Diagnosis of fetal microphthalmia using only orbital measurements such as interocular distance (IOD), and OD may neglect the presence or morphology of the fetal lens, hence failing to identify abnormalities of the fetal globe.

CASE REPORT

We hereby present a case of isolated fetal anophthalmia in two consecutive pregnancies from the same mother. Both fetuses presented as full-sized globes with absence or small size of lens under fetal ultrasound examination. Magnetic resonance imaging and pathology of the second fetus further revealed a thorough view of the underdeveloped globes. Whole exon sequencing (WES) analysis for the parents-fetus trio revealed compound heterozygous mutations of the retinoids acid gene 6 (STRA6).

CONCLUSION

Detailed examination for intraocular structures including fetal lens, in addition to orbital measurements by ultrasound is crucial for diagnosis of diseases in the A/M spectrum.

Reference standards for facial measurements in early third trimester South African fetuses, and the effect of maternal and fetal characteristics

Fetal alcohol spectrum disorder (FASD) is a major problem worldwide and dysmorphic facial features may be a prenatal biomarker for FASD. Deviations from normal facial development cannot be explored before establishing the normal variation in a specific population, since ethnic differences may exist.Objectives: Main objective: to establish reference standards for 23 facial measurements on 3D ultrasound volumes obtained between days 196 and 224 of gestation in healthy unexposed South African fetuses from an area with historically high alcohol consumption prevalence and a population group with no existing normative values. Secondary objective: to assess the confounding effect of maternal and fetal characteristics.Design: This study involves 97 women (including 43 smokers) who had been enrolled in the Safe Passage Study (SPS), a large prospective multinational cohort study assessing the effects of prenatal alcohol exposure. They had adequate 3 D ultrasound volumes of the fetal face acquired at 28⁺⁰-31⁺⁶weeks in singleton pregnancies without comorbidities, congenital abnormalities or exposure to alcohol, marijuana, or methamphetamines from 4 weeks before conception.Participants, materials, setting, methods: The participants were recruited from two residential areas of low socioeconomic status in Cape Town. Meticulous information was collected on maternal and pregnancy characteristics, including alcohol use at different time points. Gestational age (GA) was based on ultrasound biometry before 24 weeks, and 3D ultrasound volumes were acquired trans-abdominally from a sagittal and axial plane of the fetal face. Volumes were independently assessed offline by two observers and the image with the best landmark definition was used for 23 facial measurements, representing features previously described in children with FASD. The relation to the exact GA was assessed by regression analysis, the expected mean value and standard error of the estimate (SEE) was determined to transform all raw measurements into z-scores, and the effect of possible confounders on z-scores was assessed by ANOVA.Results: Ten variables changed significantly with advancing GA (extraocular diameter, anteroposterior, medio-lateral and supero-inferior ocular diameter, ocular volume, interlens distance, prenasal thickness, nasal bone length, nose length and nose protrusion) and thirteen did not (interocular distance; interocular: extraocular diameter ratio, prenasal thickness: nasal bone length ratio, pronasal-subnasal distance, subnasal-mouth distance, philtrum length, upper vermillion thickness, nose-philtrum angle, maxillary angle, facial height, facial protrusion, frontomaxillary facial angle and maxilla-nasion-mandible angle). Reference values (expected mean and SEE) for the 23 measurements were established for each day.The z-scores of all facial measurements were not independently affected by maternal age, parity, gravidity, smoking or body mass index, but infant sex and birthweight z-score significantly influenced several z-scores (infant sex for extraocular, medio-lateral, and supero-inferior ocular diameter, ocular volume, prenasal thickness and nose protrusion; birthweight z-score for extraocular diameter, interocular and interlens distance, nose protrusion and maxillary angle).Limitations: GA was not always confirmed by first trimester ultrasound and some measurements could not be obtained in all cases due to suboptimal image quality. The cohort included few heavy smokers so an effect of heavy or continued smoking cannot be ruled out, and the effect of ethnicity was not assessed.Conclusions: These are the first local reference standards for fetal facial measurements and, to our knowledge, the first reference standards for the supero-inferior ocular diameter, face protrusion, upper vermillion thickness, maxillary angle, and nose-philtrum angle. They were broadly in keeping with published references, with small discrepancies explained by minor differences in technique. Even in this narrow GA window, the distribution of many variables changed over time and normal variation was significantly influenced by fetal sex and birthweight z-score. The possible confounding effect of these factors needs to be considered when assessing the impact of harmful exposures like alcohol on facial development.

Postnatal ophthalmological characteristics in patients with congenital cataract diagnosed by fetal ultrasonography

PURPOSE

To evaluate the findings of postnatal ophthalmological examinations in patients diagnosed with cataracts by prenatal fetal sonography.

METHODS

We retrospectively identified patients diagnosed with fetal cataract without other ocular abnormalities using antenatal ultrasound. We analyzed data including the patients' family history, the presence of metabolic or systemic disease-associated cataracts, gestational age at diagnosis, fetal sonography reports, and the results of postnatal ophthalmological examinations.

RESULTS

In total, eight patients were diagnosed with cataracts by prenatal fetal ultrasonography, and all these patients showed mild to severe degrees of cataract after birth. Patients showed hyperechoic opacity of the lens in the available images. The mean gestational age at diagnosis was 26 ± 3 weeks (range, 22-28 weeks), and three patients (37.5%) had a family history of congenital cataract. All patients, except one patient who had patent ductus arteriosus, showed no systemic abnormalities associated with cataracts on postnatal evaluation. Six (75.0%) were diagnosed with bilateral cataracts after birth, and of these, two patients had been diagnosed with unilateral left cataract prenatally. Postnatal ophthalmological examination revealed that all patients showed opacities involving the nucleus of the lens and three patients (37.5%) had associated abnormalities of microcornea or microphthalmia, which were not diagnosed antenatally.

CONCLUSION

In all our subjects, the lens opacities on prenatal fetal sonography were diagnosed postnatally as cataracts involving the nucleus. A careful postnatal examination is essential to detect the presence of associated ocular abnormalities such as microcornea and/or microphthalmia and cataract in the contralateral eye in patients with congenital cataract.