Ocular fundus abnormalities in children born before 29 weeks of gestation: a population-based study

Fetal Growth Restriction Leads to an Enlarged Cup-to-Disc Ratio in Adults Born at Full Term

PURPOSE

This study explores associations between fetal growth restriction or excessive fetal growth, along with perinatal factors on the optic nerve head morphology in adulthood.

DESIGN

Retrospective cohort study.

METHODS

This retrospective cohort study involved a prospective ophthalmological examination of individuals born at full term (with a gestational age of ≥37 weeks) from 1969 to 2002. Each participant underwent nonmydriatic fundus camera photography to capture images of the optic discs, followed by manual measurements. The vertical cup-to-disc ratio (VCDR) and optic disc area were examined and analyzed in relation to the baby's birth weight relative to the gestational age. These categories included those with former moderate (birth weight percentile between the 3rd and <10th), severe SGA (below the third percentile), normal (AGA, 10th-90th percentile), and moderately (birth weight >90th-97th percentile) and severely (birth weight >97th percentile) large for gestational age (LGA) adults within the age range of 18 to 52 years.

RESULTS

Overall, 535 eyes of 280 individuals (age 29.7 ± 9.2 years, 144 females) born at full term were included. Multivariable analysis showed a significant association between a larger VCDR and the severe SGA group (B = 0.05, 95% CI 0.01-0.10; P = .02). In the univariable model, placental insufficiency was associated with VCDR (B = 0.10, 95% CI 0.01-0.19; P = .03). Other perinatal factors did not demonstrate an association with VCDR. Furthermore, there was an indication of an association suggesting a smaller optic disc area in individuals born moderately SGA at full term (B = -0.17, 95% CI -0.33 to -0.001; P = .05).

CONCLUSIONS

This study provides evidence that individuals born at-term with severe SGA have an increased VCDR, suggesting that fetal growth restriction has a lasting impact on optic disc morphology independent of prematurity throughout adulthood.

Optic atrophy in prematurity: pathophysiology and clinical features

Optic atrophy is an important cause of visual impairment in children, and the aetiological profile has changed over time. Technological advancements led by neuroimaging of the visual pathway and imaging of the optic nerve with optical coherence tomography have accelerated the understanding of this condition. In the new millennium, an increasing prevalence of prematurity as a cause of optic atrophy in children has been highlighted. This new shift has been linked with increasing rates of premature births and improved neonatal survival of preterm infants. The available literature is limited to hospital and registry-based cohorts with modest sample sizes, methodological heterogeneity and selection bias limitations. Larger studies that are better designed are required to better understand the contribution of prematurity to the disease burden. In addition to considering other life-threatening aetiologies, screening for premature birth should be covered as part of a comprehensive history when evaluating a child with paediatric optic atrophy.

Computer-assisted evaluation of retinal vessel tortuosity in moderate-to-late preterm children

PURPOSE

Since very preterm children often have increased retinal tortuosity that may indicate decisive architectural changes in the systemic microvascular network, we used a new semi-automatic software to measure retinal vessel tortuosity on fundus digital images of moderate-to-late preterm (MLP) children.

METHODS

In this observational case-control study, the global and local tortuosity parameters of retinal vessels were evaluated on fundus photographs of 36 MLP children and 36 age- and sex-matched controls. The associations between birth parameters and parameters reflecting retinal vessel tortuosity were evaluated using correlation analysis.

RESULTS

Even after incorporation of anatomical factors, the global and local tortuosity parameters were not significantly different between groups. The MLP group showed a smaller arteriolar caliber (0.53  ±  0.2) than the controls (0.56  ±  0.2; p  =  0.013). Other local tortuosity parameters, such as vessel length, distance to fovea, and distance to optic disc, were not significantly different between arteries and veins. Tortuosity in both groups was higher among vessels closer to the fovea (r  =  -0.077, p < 0.001) and the optic disc (r  =  -0.0544, p  =  0.009). Global tortuosity showed a weakly positive correlation with gestational age and a weakly negative correlation with birth weight in both groups.

CONCLUSION

MLP patients did not display increased vessel tortuosity in comparison with the controls; however, the arteriolar caliber in the MLP group was smaller than that in children born full-term. Larger studies should confirm this finding and explore associations between cardiovascular and metabolic status and retinal vessel geometry in MLP children.

Retinal and peripapillary vascular deformations in prematurely born children aged 4-12 years with a history of retinopathy of prematurity

In this study, foveal, parafoveal, peripapillary anatomical, and microvascular anomalies in prematurely born children aged 4-12 years with a history of retinopathy of prematurity (ROP) were evaluated. Seventy-eight eyes of 78 prematurely born children ([tROP]: ROP with laser treatment, [srROP]: spontaneously regressed ROP) and 43 eyes of 43 healthy children were included. Foveal and peripapillary morphological parameters (including ganglion cell and inner plexiform layer (GCIPL) thickness, peripapillary retinal nerve fiber layer (pRNFL) thickness) and vasculature parameters (including foveal avascular zone area, vessel density from superficial retinal capillary plexus (SRCP), deep retinal capillary plexus (DRCP), and radial peripapillary capillary (RPC) segments) were analyzed. Foveal vessel densities in SRCP and DRCP were increased and parafoveal vessel densities in SRCP and RPC segments vessel density were decreased in both ROP groups compared with those of control eyes. The best-corrected visual acuity was negatively correlated with pRNFL thickness in the tROP group. Refractive error was negatively correlated with vessel density of RPC segments in the srROP group. In children born preterm with a history of ROP, it was found that foveal, parafoveal, and peripapillary structural and vascular anomalies and redistribution were accompanied. These retinal vascular and anatomical structure anomalies showed close relationships with visual functions.

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.

Comparative study on optic disc features of premature infants and full-term newborns

Background

To study optic disc features of premature infants and compare to that of term infants to explore the pattern and features of newborn optic disc development and provide the basis for the diagnosis of newborn optic disc disease.

Methods

This was a prospective clinical research. Newborns underwent newborn fundus disease screening from January 1st, 2016 to October 31st, 2016 in the neonatal ward of Ruian City Maternal and Child Health Hospital were selected. RetCam 3 Version6.1.25.0 Wide-Field Digital Pediatric Retinal Imaging System developed by Clarity Medical Systems, Inc was adopted to conduct fundus examination on both eyes, 130 degree wide-angle lens was used to film the images centering optic disc.

Results

For both premature infants and full-term newborns, vertical diameter of the optic disc to lateral diameter of the optic disc ratio was > 1, and the shape of the optic disc was a vertical oval. The difference of each optic disc parameter between premature infants and full-term newborns was not statistically significant (P > 0.05). There’s a difference of constitution of sclerotic ring type on optic disc between premature infants and full-term newborns. Among which, the proportion of single ring type and double ring type in premature infants was higher than that in full-term newborns (P < 0.05). The proportion of no ring type in full-term newborns was higher than that in premature infants (P < 0.05). The proportion of mixed type had no significant difference (P > 0.05) between premature infants and full-term newborns.

Conclusions

We found that The proportion of mature types (single ring type and double ring type) in full-term newborns was higher than that in premature infants. While there’s no statistical difference of the proportion of mixed types between premature infants and full-term newborns. Double ring type was a normal stage of the development of optic disc.

The impact of maternal asthma during pregnancy on offspring retinal microvascular structure and its relationship to placental growth factor production in utero

Asthma is a common chronic disease in pregnancy that affects placental function and fetal growth and associated with cardio-metabolic disorders in the offspring but the mechanisms are unknown. This study explored whether maternal asthma in pregnancy is associated with the development of offspring microvascular structure and whether it was related to biomarkers of angiogenesis in utero. Children aged 4 to 6 years, born to either asthmatic mothers (n = 38) or healthy controls (n = 25), had their retinal microvascular structure examined. Maternal plasma PlGF concentrations at 18 and 36 weeks' gestation were measured. There was a significant global difference in all retinal microvascular measures between children of asthmatic mothers relative to controls and increased retinal venular tortuosity in children born to asthmatic mothers (7.1 (95% CI 0.7-13.5); P = .031). A rise in plasma PlGF from 18 to 36 weeks' gestation was observed in the control population which was significantly lower in the asthma group by 190.9 pg/mL. PlGF concentrations were correlated with microvascular structure including arteriolar branching and venular tortuosity. These exploratory findings indicate that exposure to maternal asthma during pregnancy is associated with persistent changes in microvascular structure in childhood that may be driven by alterations to angiogenic mechanisms in utero.

Utility of Magnetic Resonance Imaging (MRI) in Children With Strabismus

PURPOSE

Magnetic resonance imaging (MRI) of the brain can provide valuable information about structural abnormalities in strabismus. The aim of this study was to evaluate the utility of MRI in this regard and to identify risk factors for abnormal MRI results in children with strabismus.

METHODS

A retrospective analysis of children <18 years of age presenting with strabismus, who underwent brain MRI at Pusan National University Hospital (Busan, Korea) between January 2012 and March 2017, was performed. Clinical characteristics, MRI results, and ophthalmologic findings were reviewed. Findings were classified as normal or abnormal according to MRI results. Additionally, patients were divided according to age to compare characteristics of infantile and childhood strabismus.

RESULTS

A total of 90 patients (47 [52.2%] male, 43 [47.8%] female; mean age, 2.19 ± 0.53 years) were enrolled. Of those, 64 (71.1%) presented with normal and 26 (28.9%) with abnormal MRI results. The age at presentation was lower and abnormal findings on fundus examination were more common in the abnormal MRI group (P = .002 and P = .008, respectively). Among the patients, 46 (51.1%) had infantile strabismus and 44 (48.9%) had childhood strabismus. Global developmental delays, speech delays, and MRI abnormalities were more common in patients with infantile than in those with childhood strabismus. Ptosis and headaches were more common in patients with childhood strabismus (P = .025, P = .025, respectively).

CONCLUSION

Brain MRI was helpful for accurate diagnosis and treatment of strabismus in younger children, those with abnormal findings on fundus examination, and infants with developmental, especially speech, delays.

Visual Function and Fundus Morphology in Relation to Growth and Cardiovascular Status in 10-Year-Old Moderate-to-Late Preterm Children

PURPOSE

To study visual function and ocular fundus morphology in relation to growth, metabolic status, and blood pressure in moderate-to-late preterm (MLP) children at 10 years of age.

DESIGN

Prospective cohort study.

METHODS

In this population-based observational study, nonsyndromic MLP children born in Gothenburg, Sweden, were examined neonatally in the years 2002-2003 concerning length, weight, head circumference, and insulin-like growth factor I (IGF-I). At 10 years of age, 33 children (10 girls) were examined regarding previously mentioned variables, and regarding visual acuity, refraction, fundus morphology, IGF binding protein 3, leptin, adiponectin, and blood pressure. An age- and sex-matched control group consisted of 28 children (9 girls).

RESULTS

Myopia was more commonly found in MLP children than in controls (P = .004, 95% CI 1.8 to 49.8). The MLP group had smaller optic disc area (P = .01, 95% CI -0.5 to -0.1), smaller rim area (P = .001, 95% CI -0.5 to -0.2), fewer branching points (P = .0001, 95% CI -5.7 to -2.1), and higher index of tortuosity of arteries (P = .03, 95% CI 0.002 to 0.03) and veins (P = .02, 95% CI 0.003 to 0.02). Refraction correlated with IGF-I (P = .0005, r_s = 0.60 in right eye, and P = .002, r_s = 0.55 in left eye) at 10 years of age. Tortuosity of arteries at assessment correlated with neonatal IGF-I levels (P = .03, r_s = -0.39). Tortuosity of veins correlated with a leptin/adiponectin ratio at assessment (P = .04, r_s = 0.37).

CONCLUSION

The findings suggest that being born MLP is associated with myopia, smaller optic disc and rim areas, and abnormal retinal vascularization. Furthermore, metabolic status and growth factors seem to have an impact on ocular development.

The rim area of the optic nerve head, assessed with Heidelberg retina tomography, is smaller in prematurely born children than in children born at term

PURPOSE

To examine the optic nerve head with Heidelberg tomography (HRT) in prematurely born school-age children and compare them to children born at term.

METHODS

Sixty-three 5-16-year-old children born with a gestational age (GA) of ≤32 weeks were included in the study and compared to 54 children of the same age, born at term. In the preterm group, 29 children had had retinopathy of prematurity (ROP) and nine children had neurological complications. The optic nerve head was assessed with HRT. Three measurements were performed, and the different topographic parameters were noted.

RESULTS

Rim area of the optic nerve was significantly smaller in prematurely born children than in children born at term. The mean difference was 0.146 mm² (p = 0.02). No difference between the groups was found regarding disc area or cup area. In the preterm group, both disc and rim areas were reduced with increasing GA. No correlations with birthweight, ROP or neurological complications were found.

CONCLUSION

Reduced rim area of the optic nerve head was found in preterm children of school age. Previous ROP or neurological complication did not influence the result, suggesting the preterm birth per se was the reason for the reduction. Establishing whether this finding was caused by disturbed maturation of the optic nerve or by injury of the axons, or a combination of the two, will require further research.

Comparison of optic disk features in preterm and term infants

PURPOSE

To compare the optic disk features of preterm and term infants.

METHODS

Digital fundus images of preterm infants were compared with those of infants born at term, imaged within 1 week of birth. The optic disk horizontal diameter to vertical diameter ratio, the disk-macula to disk-diameter ratio, and the presence or absence of double ring sign was noted.

RESULTS

Images of 649 infants (324 preterm and 325 term) were analyzed. Of the preterm infants, 129 (40%) had a double ring sign, compared to 4% in term infants. The double ring was seen more frequently in infants of European descent and was more common with younger gestational age. The mean horizontal to vertical disk diameter in preterm infants on first examination was 0.75 ± 0.063, increasing to 0.80 ± 0.069 at final examination. Term infants had a horizontal to vertical disk diameter ratio of 0.79 ± 0.064. At final examination, the ratio of disk-to-macula distance to the horizontal disk diameter was 3.9 in preterm infants and 3.7 for term infants.

CONCLUSIONS

In our study population preterm infants often had a double ring sign around the optic disk in the absence of optic nerve hypoplasia. Preterm disks tend to be more vertically oval, which becomes less oval closer to term. The mean disk-to-macula to disk-diameter ratio among normal preterm infants was higher than previously reported.

The range of peripapillary retinal nerve fibre layer and optic disc parameters in children aged up to but not including 18 years of age, as measured by optical coherence tomography: protocol for a systematic review

BACKGROUND

The parameters of the optic disc and peripapillary retinal nerve fibre layer (pRNFL) in children may vary with disease processes that contribute to visual impairment and blindness and so could be useful as an objective measure in at-risk children. There is no standardised reference for the normal parameters of the optic disc and pRNFL in children; however, there are a large number of small individual studies that have been undertaken to look at these measures.

METHODS

A systematic review of current literature on the range of pRNFL and optic disc parameters in children aged less than 18 years will be performed. Studies will be considered for review if they report numerical data on optic disc and pRNFL parameters, measured using optical coherence tomography. Outcome measures will include mean pRNFL thickness and cup-disc ratio. The bibliographic databases Medline, CINAHL, EMBASE, Scopus and Web of Science will be systematically searched from 1991. Screening of search results will be conducted by two authors working independently, as will extraction of primary and secondary outcome data. Ten per cent of all other data extraction will be checked by a second author. Results will be compiled and presented in evidence tables. Where possible and appropriate, study-specific estimates will be combined to obtain an overall summary estimate of pRNFL thickness and cup-disc ratio across studies and results will be presented by age of population. Subgroup analyses will be undertaken for children of different ethnicities.

DISCUSSION

This review aims to provide an overview of the parameters of the optic disc and pRNFL in children of different ages in order to identify gaps in knowledge and to improve understanding of what might be considered within/outside the range of normality. The findings will be presented in peer-reviewed journals and will be presented at conferences.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42016033068.

Size of the intracranial optic nerve and optic tract in neonates at term-equivalent age at magnetic resonance imaging

BACKGROUND

The expected MRI-based dimensions of the intracranial optic nerve and optic tract in neonates are unknown.

OBJECTIVE

To evaluate the sizes of the intracranial optic nerve and optic tract in neonates at term-equivalent age using MRI.

MATERIALS AND METHODS

We retrospectively analyzed brain MRI examinations in 62 infants (28 boys) without intracranial abnormalities. The images were obtained in infants at term-equivalent age with a 1.5-tesla MRI scanner. We measured the widths and heights of the intracranial optic nerve and optic tract and calculated the cross-sectional areas using the formula for an ellipse.

RESULTS

The means ± standard deviation of the width, height and cross-sectional area of the intracranial optic nerve were 2.7 ± 0.2 mm, 1.7 ± 0.2 mm and 3.5 ± 0.5 mm(2), respectively. The width, height and cross-sectional area of the optic tract were 1.5 ± 0.1 mm, 1.6 ± 0.1 mm and 2.0 ± 0.2 mm(2), respectively. Using univariate and multivariate analyses, we found that postmenstrual age showed independent intermediate positive correlations with the width (r = 0.48, P < 0.01) and cross-sectional area (r = 0.40, P < 0.01) of the intracranial optic nerve. The lower bounds of the 95% prediction intervals for the width and cross-sectional area of the intracranial optic nerve were 0.07 × (postmenstrual age in weeks) - 0.46 mm, and 0.17 × (postmenstrual age in weeks) - 4.0 mm(2), respectively.

CONCLUSION

We identified the sizes of the intracranial optic nerve and optic tract in neonates at term-equivalent age. The postmenstrual age at MRI independently positively correlated with the sizes.

Cup-to-disc and arteriole-to-venule ratios in preterm birth

AIMS

To investigate the influence of preterm birth on the optic disc and retinal vessels by measurements of cup-to-disc (C/D) ratio and arteriole-to-venule (A/V) ratio.

METHODS

Eighty-three eyes of 42 preterm births were included. In the age- and sex-matched control group, 83 eyes of 42 full-term births were used. Fundus color photographs were taken. ImageJ software was used to calculate C/D and A/V ratios from the fundus images.

RESULTS

Fundus photographs were taken at 8.01 ± 2.22 years of age for the preterm group and 8.01 ± 2.13 years of age for the control group. The mean gestational age of the preterm group was 27(4)/7 weeks (range, 24-34 weeks). The preterm group had significantly larger C/D ratio and smaller A/V ratio (mean ± standard deviation: 0.46 ± 0.12 and 0.59 ± 0.08, respectively) than the control group (0.36 ± 0.07 and 0.68 ± 0.07, respectively) after spherical equivalent refractive error was adjusted.

CONCLUSIONS

Preterm birth is significantly associated with larger C/D ratio and smaller A/V ratio. These findings show the effect of preterm birth on the development of optic disc and retinal vessel development.

Comparison of Retinal Nerve Fiber Layer Thickness in Terms of Birth Weight in Prematurely Born Children

PURPOSE

To study the potential effects of both prematurity and the sub-groups of low birth weight on thickness of RNFL.

METHODS

Prospective case series of 26 preterm school-aged children with low birth weight whose retinal nerve fiber layer analyses with RTVue-100 Fourier-domain optic coherence tomography were performed in 2013 at the Department of Ophthalmology, Erzurum Region Education and Training Hospital.

RESULTS

The mean retinal nerve fiber layer thicknesses were 100.6 ± 13.3 microns in extremely low birth weight, 103.9 ± 8.4 microns in very low birth weight, and 104.1 ± 10.8 microns in low birth weight groups. There was no significant difference in RNFL among the groups.

CONCLUSIONS

No significant relationship was found between birth weights and retinal nerve fiber layer thickness of preterm children who were appropriate for gestational age.

Determining the size of retinal features in prematurely born children by fundus photography

PURPOSE

The purpose was to study the effect of prematurity on the macula-disc centre distance and whether it could be used as a reference tool for determining the size of retinal features in prematurely born children by fundus photography.

METHODS

The macula-disc centre distance of the left eye was measured in pixels from digital fundus photographs taken from 27 prematurely born children aged 10-11 years with Topcon fundus camera. A conversion factor for Topcon fundus camera (194.98 pixel/mm for a 50° lens) was used to convert the results in pixels into metric units.

RESULTS

The macula-disc centre distance was 4.74 mm, SD 0.29. No correlation between ametropia and the macula-disc centre distance was found (r = -0.07, p > 0.05). One child (subject 20) had high myopia and retinopathy of prematurity (ROP), and the macula-disc centre distance was longer than average (6.35 mm).

DISCUSSION

The macula-disc centre distance in prematurely born children at the age of 10-11 years provides an easy-to-use reference tool for evaluating the size of retinal features on fundus photographs. However, if complications of ROP, for example temporal macular dragging or high ametropia, are present, the macula-disc centre distance is potentially altered and a personal macula-disc centre distance should be determined and used as a refined reference tool.

Evaluation of optic nerve development in preterm and term infants using handheld spectral-domain optical coherence tomography

PURPOSE

To evaluate effects of prematurity on early optic nerve (ON) development and the usefulness of ON parameters as indicators of central nervous system (CNS) development and pathology.

DESIGN

Prospective, cross-sectional, longitudinal study.

PARTICIPANTS

Forty-four preterm infants undergoing retinopathy of prematurity (ROP) screening and 52 term infants.

METHODS

We analyzed ON from portable handheld spectral-domain optical coherence tomography (SD-OCT) images (Bioptigen, Inc, Research Triangle Park, NC) of 44 preterm and 52 term infants. The highest-quality ON scan from either eye was selected for quantitative analysis. Longitudinal analysis was performed at 31-36 weeks and 37-42 weeks postmenstrual age (PMA). Preterm ON parameters also were assessed for correlation with indicators of cognitive, language, and motor development and CNS pathology.

MAIN OUTCOME MEASURES

Vertical cup diameter (vCD), vertical disc diameter (vDD), vertical cup-to-disc ratio (vCDR), cup depth, and indicators of neurocognitive development and CNS pathology.

RESULTS

At 37-42 weeks PMA, preterm infants had larger vCD and vCDR than term infants (908 vs. 700 μm [P<0.001] and 0.68 vs. 0.53 μm [P<0.001], respectively), whereas cup depth and vDD were not significantly different. Longitudinal changes (n = 26 preterm eyes; mean interval, 4.7 weeks) in vDD and in vCDR were an increase of 74 μm (P = 0.008) and decrease of 0.05 (P = 0.015), respectively. In preterm infants (n = 44), periventricular leukomalacia was associated with larger vCD (1084 vs. 828 μm; P = 0.005) and vCDR (0.85 vs. 0.63; P<0.001), posthemorrhagic hydrocephalus was associated with shallower cup (331 vs. 456 μm; P = 0.030), and clinical magnetic resonance imaging was associated with larger vCDR (0.73 vs. 0.64; P = 0.023). In 23 preterm infants with Bayley Scales of Infant Development scores, larger vCDR was associated with lower cognitive scores (P = 0.049).

CONCLUSIONS

This is the first analysis of ON parameters in premature infants using SD-OCT. It demonstrated that by age of term birth, vCD and vCDR are larger in preterm infants who were screened for ROP than in term infants. In this prospective pilot study, ON parameters in these preterm infants associate weakly with CNS pathology and future cognitive development. Future prospective studies with larger numbers are necessary before further conclusions can be made.

Assessment of the optic nerve head parameters using Heidelberg retinal tomography III in preterm children

Background

Variations in optic nerve head morphology and abnormal retinal vascular pattern have been described in preterm children using digital image analysis of fundus photograph, optical coherence tomograph and serial funduscopy. We aimed to compare the optic nerve head parameters in preterm and term Malay children using Heidelberg Retinal Tomograph III.

Design

A cross sectional study.

Methodology/Principal Findings

Thirty-two preterm Malay children who were born at up to 32 weeks postconception, and 32 term Malay children aged 8–16 years old were recruited into this cross sectional study, which was conducted in the Hospital Universiti Sains Malaysia, Malaysia from January to December 2011. Their optic nerves were scanned and analyzed using a Heidelberg Retinal Tomography (HRT) III (Heidelberg Engineering, Germany). Preterm children showed an increased rim volume (SD) (0.56 (0.26) vs 0.44 (0.18) mm³, respectively), smaller cup shape (SD) (0.18 (0.07) vs 0.25 (0.06) mm, respectively), increased height variation contour (SD) (0.44 (0.14) vs 0.35 (0.08) mm, respectively), and increased cup depth (SD) (0.24 (0.11) vs 0.17 (0.05) mm³, respectively) when compared to their normal peers (p<0.05). There were no significant differences in the mean disc area, cup area, cup to disc ratio or rim area between the preterm and term children (p>0.05) in our study.

Conclusions/Significance

Preterm children exhibit different characteristics of optic nerve head parameters with HRT III analysis. Increased cup depth in preterm children suggests a need for close observation and monitoring. It may raise suspicion of pediatric glaucoma when proper documentation of intraocular pressure and clinical funduscopy are unsuccessful in uncooperative children.

Pathways of neuronal and cognitive development in children born small-for-gestational age or late preterm

OBJECTIVE

To assess the effects of late small-for-gestational-age (SGA) birth and late prematurity on cognitive outcomes and structural changes in the central nervous system at primary school age, using a novel approach to examine changes in neuronal integrity of the retina.

METHODS

We conducted a cross-sectional study of 347 children aged 6-13 years, including in the analysis only infants born after 34 weeks' gestation. We recorded all perinatal outcomes through a survey of parents. Neuronal damage was evaluated using optical coherence tomography of the retina. In a subgroup of 112 children aged 6-8 years, visuospatial perception was evaluated with the Children's Bender Visual Motor Gestalt Test.

RESULTS

The proportions of SGA and late preterm children were 11.8 and 6.3%, respectively. Prematurity and SGA were simultaneously present in five children. When compared with controls, SGA children showed significantly lower than average retinal nerve fiber layer (RNFL) thickness (94.1 vs 98.8 μm; P = 0.007) and an increased percentage of abnormal Bender scores (27.3 vs 6.2%; P = 0.017) (odds ratio 5.6 (95% CI, 1.2-26.8)). These differences increased when late SGA infants with a birth weight below the 3(rd) percentile were compared with SGA infants with a birth weight between the 3(rd) and 10(th) percentiles and with controls, for RNFL thickness (92.5 vs 94.6 and 98.8 μm, respectively; P = 0.021) and abnormal Bender tests (33.3 vs 25.0 and 6.2%, respectively; P = 0.036). However, no differences were found in retinal structure and visuomotor performance between late preterm and term infants.

CONCLUSIONS

These data suggest that late SGA and late prematurity induce a distinct neuronal pattern of structural changes that persist at school age. Late-onset SGA infants are at increased risk for axonal loss in the retina and present specific visuomotor difficulties.

Racial variation in optic nerve head parameters quantified in healthy newborns by handheld spectral domain optical coherence tomography

PURPOSE

To characterize optic nerve head (ONH) morphology and parameters, including vertical disk diameter, vertical cup diameter, and vertical cup/disk ratio in healthy, full-term newborns using a handheld spectral domain optical coherence tomography (SD-OCT) device.

METHODS

In this prospective observational case series, healthy white, black, and Hispanic full-term newborns delivered at the Duke Birthing Center between August 2010 and May 2011 underwent dilated fundus examination and SD-OCT imaging of the optic nerve in each eye. OCT parameters were calculated and compared for each group of infants.

RESULTS

A total of 58 consecutive newborns of white (n = 22), black (n = 15) and Hispanic (n = 21) ethnicity were included. Mean vertical disk diameter in white, black, and Hispanic newborns was 1.29 ± 0.15 mm (standard deviation), 1.38 ± 0.14 mm, and 1.38 ± 0.14 mm, respectively (white versus Hispanic, P = 0.02; white versus black, P = 0.07). Mean vertical cup diameter in white, black, and Hispanic newborns was 0.44 ± 0.15 mm, 0.56 ± 0.23 mm, and 0.46 ± 0.30 mm, respectively (white versus black, P = 0.03). Mean vertical cup/disk ratio was 0.34 ± 0.10 for white, 0.40 ± 0.17 for black, and 0.33 ± 0.20 for Hispanic newborns (P = 0.07 for white versus black).

CONCLUSIONS

Handheld SD-OCT is an effective means of imaging the ONH in newborns. Racial differences in cup/disk ratio are present at birth. These data may serve as the beginning of a normative dataset for characterizing development of the ONH as well as for comparison to the neonatal ONH in disease states.

Effect(s) of preterm birth on normal retinal vascular development and oxygen-induced retinopathy in the neonatal rat

PURPOSE

Maturity is a critical factor in the pathogenesis of retinopathy of prematurity (ROP). One widely used method for studying this condition is that of oxygen-induced retinopathy (OIR). The general conditions of an OIR term animal, both at the time of birth and following birth, differ from those of the preterm infant. This, to simulate preterm conditions and to provide a basis for further studies on ROP, we investigated the effect(s) of preterm birth on retinal vascularization using the neonatal rat.

MATERIALS AND METHODS

Sprague-Dawley (SD) rats were delivered preterm by caesarean section on the day 19 of gestation. Term pups were used as controls. On the day of birth, preterm and term pups were housed under conditions of room air or cyclic oxygen. Retinas of pups housed in room air on days 4, 7, 10, 14, 18 and 22, as well as pups housed in oxygen on days 14, 18, and 22 were whole-mounted and stained with isolectin-B4. On day 18, cross-sections of the retina were cut and stained with hematoxylin and eosin for the identification of preretinal neovascular tufts. Images of avascular and neovascular areas were compared using light and fluorescence microscopy.

RESULTS

Preterm pups had significantly larger avascular retinal areas than term rats on the various postnatal days. After exposure to cyclic oxygen, preterm pups demonstrated significantly larger avascular (days 14 and 18) and neovascular areas (day 18) compared with term rats. On day 22, residual retinopathy of preterm pups was greater than that of term pups.

CONCLUSIONS

Preterm birth of rats, which are comparable in their physiology to humans, had negative effects on retinal vascularization. The impaired retinal vascular development and subsequent vasoproliferation resulting from hyperoxia in preterm pups is more severe and enduring.

RetCam image analysis of the optic disc in premature infants

PURPOSE

To evaluate the correlation between optic disc parameters and birth weight or gestational age in premature infants.

METHODS

RetCam fundal images were taken of 97 premature infants who needed screening for retinopathy of prematurity and who had no ischemic brain injury. The images were taken at a postmenstrual age of 36 weeks and analyzed. The optic disc cup to disc ratio, optic disc area, rim area, and cup to disc area ratio were calculated using image analysis. We evaluated the relationship between these optic disc parameters and gestational age or birth weight.

RESULTS

The optic cup to disc ratio was less than 0.15 in 139 eyes (71.6%) and 0.5 or more in six eyes (3.1%). The optic cup disc area ratio was less than 0.05 in 146 eyes (75.3%) and 0.3 or more in four eyes (2.1%). On evaluating the association between optic disc parameters and gestational age or birth weight, optic disc cup to disc ratio, optic disc area, rim area, and cup to disc area ratio did not show significant relationships.

CONCLUSION

The optic disc parameters of premature infants had no correlation with birth weight and gestational age.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Longitudinal study of optic cup progression in children

PURPOSE

To determine the normative rate of cup-to-disc-ratio (C:D) progression in children and the effect of prematurity and low birth weight on this rate.

METHOD

In a single pediatric ophthalmology practice, a single examiner evaluated optic cup size by serial ophthalmoscopy over a minimum of 5 years in 92 patients (184 eyes) without intraocular surgery or optic nerve disease. A cross-sectional analysis of C:D was performed per year of age from 0 to 10 years and linear regression was used to compare C:D progression between preterm and term children and between low versus normal birth weight children.

RESULTS

Children exhibited progressive optic cupping. In term children, mean C:D increased by 0.0075 per year. Rate of mean C:D progression was double in children born preterm: 0.0160 (P = .049, comparison to term) per age-year. A similar, nonsignificant trend is observed when comparing low birth weight to normal children (P = .131).

CONCLUSION

Prematurity and low birth weight are associated with increased rate of cupping in children. Clinicians should recognize that C:D progression is not a specific sign of glaucoma in children.

Relationships between ophthalmological and neuropaediatric findings in children adopted from Eastern Europe

PURPOSE

This study aimed to evaluate and relate visual function, ocular dimensions and neuropaediatric findings in adoptees from Eastern Europe.

METHODS

We studied 72 of 99 children, born during 1990-95 and adopted from Eastern Europe to western Sweden during 1993-97. The children (mean age 7.5 years, range 4.8-10.5 years; 41 boys, 31 girls) were examined after a mean period of 5 years post-adoption by a multidisciplinary team. Correlations between ophthalmological findings and neuropaediatric data were analysed.

RESULTS

Bivariate and regression analyses indicate a significant positive correlation between visual acuity (VA) and perceptual organization (p < 0.001), as well as between strabismus and verbal comprehension (p < 0.02). Fetal alcohol syndrome (FAS) was correlated with low VA (p < 0.02), subnormal stereovision (p < 0.009) and small optic discs (p < 0.02). Small head circumference was related to low VA (p < 0.015) and small optic discs (p < 0.03). Furthermore, small optic discs were related to low birthweight (p < 0.005) and preterm birth (p < 0.01). Large optic cups were correlated with poorer perceptual organization (p < 0.02).

CONCLUSIONS

In this group of adoptees from Eastern Europe, ophthalmological findings were correlated to neuropaediatric findings, especially those arising from prenatal adverse events resulting in growth deficiency and central nervous system damage. Therefore, it is important and valuable with an ophthalmological examination in children adopted from Eastern Europe.

Birth weight deviation and early postnatal growth are related to optic nerve morphology at school age in children born preterm

The aim of this study was to evaluate the influence of early and later postnatal growth variables on optic disc morphology in children (n = 53) born at gestational age <32 wk. On fundus photographs taken at a median age of 5.4 y, the optic discs were evaluated using digital image analysis and compared with those of a control group (n = 203). The results were analyzed in relation to gestational age, birth weight (BW) SD score (SDS), IGF-1 weight at postmenstrual age 32 wk (SDS), and weight, length, and head circumference (SDS) at follow-up. The preterm children's optic disc and neuronal rim areas were smaller than in the control group. Low BW (SDS) and weight at wk 32 (SDS) were associated with larger area of the optic cup and reduced neuronal rim area. Preterm children with known brain lesions (n = 6) had significantly larger cups than preterm children without known brain lesions. The association found between both low BW and poor early growth and later reduced neuronal tissue of the optic nerve indicate that early weight gain is important for neural development in preterm children.

Visual fields and optic disc morphology in very low birthweight adolescents examined with magnetic resonance imaging of the brain

PURPOSE

We aimed to evaluate visual fields (VFs) and optic disc morphology in very low birthweight (VLBW) adolescents compared with age- and gender-matched controls, and to relate the findings to magnetic resonance imaging (MRI) results.

METHODS

Fifty-nine VLBW adolescents and 55 age- and gender-matched controls with normal birthweight were examined. Visual fields were tested using computerized rarebit perimetry (RB). Optic nerve and retinal vessel morphology were evaluated by digital image analysis of fundus photographs. Brain MRI was conducted in the VLBW subjects.

RESULTS

Ten of the 57 VLBW subjects (p = 0.022) had subnormal VF results defined as a mean hit rate below the fifth percentile of the controls (i.e. < 89%). All of these also had significantly lower mean hit rates (p = 0.039) in the inferior hemifield. Sixteen of 57 (28%) VLBW subjects had white matter damage of immaturity (WMDI) on MRI. Six of 15 subjects with WMDI (who underwent VF testing) also had subnormal RB results, compared with four of 39 with normal MRI findings (p = 0.02). The mean neural retinal rim area was 9% smaller (p = 0.018) in the VLBW group than in the control group. The VLBW adolescents had a significantly higher index for tortuosity of arterioles than the controls (p < 0.001).

CONCLUSIONS

In the present study, 18% of all VLBW adolescents and 40% of those with WMDI had subnormal RB VF findings. The VLBW group had increased arterial tortuosity and a somewhat smaller (9%) mean neural retinal rim area than the control group. Thus sequels to VLBW appear to persist in adolescence.

Morphological aspects of dental hard tissues in primary teeth from preterm infants

BACKGROUND

Preterm children with very low birth weight suffer from several neonatal and post-natal complications that may affect the mineralization of the teeth. Clinical studies have shown enamel aberrations in both dentitions.

AIMS

The aims of this study were to describe enamel histo-morphology in primary teeth, and investigate the relationship between medical history and morphological appearance.

DESIGN

Dental enamels in 44 exfoliated primary teeth, from 14 children with a gestational age below 29 weeks and with a very low birth weight, were investigated, using polarized light microscopy (POLMI) and under a scanning electron microscope (SEM).

RESULTS

The neonatal line was found in 1/3 of the sections located coronally of the crown. In the post-natal enamel, 31 teeth showed a degree of porosity higher than 5% with a varying extension. More than half of the teeth showed one or more increment lines. The SEM analysis confirmed the POLMI findings with irregular prisms covered with a structure-less film.

CONCLUSIONS

Enamel from primary teeth of preterm children was found to have a high frequency of mineralization disturbances found in POLMI and SEM. The morphological features of the enamel from preterm children do not reflect the disturbances on general growth and development occurred during the neonatal period.

Abnormal vessel morphology in boys born after intracytoplasmic sperm injection

AIM

Children born after intracytoplasmic sperm injection (ICSI) are at risk of preterm birth, low birth weight and perinatal morbidity which may predispose for diseases of the central nervous and vascular systems. Our aim was to investigate the ocular fundus morphology in children born after ICSI.

METHOD

Children born after ICSI (n = 82) had ocular fundus photographs taken at the age of 5 years and results were compared with those of a control group (n = 203). The ocular fundus morphology with the central retinal vessels was evaluated by digital image analysis.

RESULTS

Children born after ICSI (n = 57) had abnormal retinal vascularization as evidenced by a lower number of vascular branching points compared with the control group (n = 181) (p = 0.0002). A gender difference was found whereby the ICSI boys (n = 35) had significantly fewer retinal branching points (median 24, range 19-29.5) compared with the control boys (median 27.5, range 20-37) (p < 0.0001).

CONCLUSION

Our findings showed that ICSI boys have abnormal vessel morphology as demonstrated by a reduced number of central retinal branching points. The difference still remained after elimination of factors earlier shown to be associated with a low number of vascular branching points, i.e. low birth weight and preterm, suggesting other mechanisms responsible for the low number of vascular branching points.

Optic nerve hypoplasia potentiates retinopathy of prematurity

The risk of progression to threshold retinopathy of prematurity correlates with the area of avascular retinas and inversely with the degree of vascular maturity. Asymmetric retinal ablation was performed in two patients and asymmetric retinopathy of prematurity progression was observed in two infants with optic nerve hypoplasia.

Ocular complications at the limits of viability

AIM

To evaluate the incidence of retinopathy of prematurity (ROP) and other ocular morbidities in extremely premature infants.

METHODS

A retrospective analysis of the prevalence and nature of ocular abnormalities in a cohort of 22 extremely pre-term infants born <25 + 0 weeks of estimated gestational age (GA) was performed.

RESULTS

The children were grouped according to the observed disorder: 13 out of 22 (59%) neonates with mild ophthalmologic findings (ROP < or = stage II) [Group 1], 5 out of 22 (23%) infants with ROP stage III or more (Group 2) and 4 out of 22 (18%) neonates with severe ocular morbidity (congenital cataract, microphthalmia, partial optic nerve atrophy and corneal perforation due to an ulcer with lens protrusion), partly combined with ROP > or = stage III (three of four). One child of 22 (5%) needed laser therapy. Out of 22 admitted infants, 20 (91%) were discharged alive.

CONCLUSION

The high rate of ocular morbidity besides ROP in extremely pre-term infants is noteworthy. Mechanisms influencing the postnatal development of the eye, especially their relation to the grade of prematurity and neonatological therapeutical strategies, require further investigations.

RetCam image analysis of optic disc morphology in premature infants and its relation to ischaemic brain injury

AIMS

To assess optic disc characteristics in premature infants with and without ischaemic brain injury and to evaluate the role of optic disc morphology in dating the injury.

METHODS

RetCam fundal images, cranial ultrasounds and magnetic resonance imaging (MRI) of 109 premature infants were analysed. The study cohort was divided into subgroups depending on the presence or absence of periventricular leucomalacia (PVL) and intraventricular haemorrhage (IVH). The control group consisted of infants with normal neuroimaging at term and 2 years of age. Using the image analysis software of the RetCam, optic disc diameter (ODD), optic disc area (ODA), and optic cup area (OCA) were measured at 33-34 weeks gestational age. As serial cranial ultrasonography had been performed, it was possible to date the brain injury in those infants with periventricular white matter (PVWM) damage.

RESULTS

Although there was a trend towards reducing ODD, ODA, and OCA with increasing severity of IVH, only the IVH 4 group differed significantly from the controls for these parameters (p = 0.002, p = 0.02, and p = 0.04, respectively). 44.4% of infants with grade 4 IVH had small discs. Only one patient had a large cup in a normal sized disc; this patient had IVH 4. In patients with PVWM damage, the median time of insult was 27 weeks in those with small discs and 28 weeks in those with normal discs. This difference was not significant (p = 0.23).

CONCLUSIONS

Premature infants with IVH 4 have an increased incidence of optic nerve hypoplasia. We found no association between disc morphology and timing of brain injury.

Visual function and ocular features in children and adolescents with attention deficit hyperactivity disorder, with and without treatment with stimulants

AIMS

To investigate visual function and ocular features in children with attention deficit hyperactivity disorder (AD/HD) and establish whether treatment with stimulants is reflected in functioning of the visual system.

METHODS

Detailed ophthalmologic evaluations without and with stimulants were performed in 42 children (37 boys) with AD/HD, mean age 12 years, and compared with a reference group (ref; n=50; mean age 11.9 years; 44 boys). For a comparison between two groups, Mann-Whitney's U-test was used for ordered and continuous variables; for dichotomous variables, Fisher's exact test was used. For paired comparison (with and without treatment), sign test was used.

RESULTS

In all, 83% had visual acuity of >0.8 (<0.1 logMAR) without treatment, 90% with stimulants (ref 98%; P=0.032 and n.s., respectively). Heterophoria was found in 29% without, and in 27% with, stimulants (ref 10%; P=0.038 and n.s., respectively) and subnormal stereovision (>60 s of arc) in 26% (ref 6%; P=0.016) without stimulants, and in 27%, with (P=0.014). Abnormal convergence (>6 cm or absent) was noted in 24% (ref 6%; P=0.031) without treatment and in 17%, with (n.s.). Astigmatism (> or =1.0 D) was observed in 24% (ref 6%; P=0.03), and signs of visuoperceptual problems in 21% (ref 2%; P=0.007). We found smaller optic discs (n=8/38) and neuroretinal rim areas (n=7/38) (P<0.0001) and decreased tortuosity of retinal arteries (n=6/34) (P=0.0002) than that of controls.

CONCLUSIONS

Children with AD/HD had a high frequency of ophthalmologic findings, which were not significantly improved with stimulants. They presented subtle morphological changes of the optic nerve and retinal vasculature, indicating an early disturbance of the development of these structures.

Subnormal visual perception in school-aged ex-preterm patients in a paediatric eye clinic

PURPOSE

The aim of this study was to assess visual perception at school age of children born preterm with known lesions to the posterior visual pathways or with ophthalmologic signs that might indicate such lesions.

METHODS

The study group consisted of 91 patients born before the 37th gestational week. Visual perception was assessed using the TVPS-R (Test of Visual Perceptual Skills - Revised) and a structured interview. In addition, ophthalmologic and orthoptic examinations were performed.

RESULTS

On the test of visual perception, 67% of the patients had results below the third percentile of the American reference group. This is to be compared with 10% of Swedish full-term controls. Scores below the third percentile were observed in 87% of the patients with known brain lesions, 48% of those with strabismus without known brain lesion, and 86% of those with reduced visual acuity in the absence of strabismus and known brain lesion.

CONCLUSIONS

Reduced visual perception is common among children born preterm who have strabismus and/or reduced visual acuity, as well as in those with known brain lesions. This study emphasises the need to find tools to identify and assess those patients who have visual perceptual problems that may restrict their ability to meet the demands of daily life.

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSION

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

Sequelae of chorioamnionitis

Chorioamnionitis correlates to preterm delivery prior to 30 weeks of gestation. In most studies, proxies of intrauterine infection (clinical chorioamnionitis, histological chorioamnionitis, intra-amniotic increase in cytokines) are associated with acute neonatal morbidity and mortality and, at least to some degree, with neurological impairments (periventricular leukomalacia, intraventricular hemorrhage, cerebral palsy, polymicrogyria), chronic lung disease, and involution of the thymus in the preterm infant. The connection to visual impairment and cognitive deficits is uncertain or unknown. Full-term babies exposed to intrauterine infection often present with depressed Apgar scores and neonatal encephalopathy, and are at markedly increased risk of developing cerebral palsy. The infectious/inflammatory mechanisms involved are incompletely understood, and the types of microbes, as well as the genetic characteristics of the host adaptive and innate immune response, need to be better characterized.