Characteristics of peripapillary retinal nerve fiber layer in preterm children

Imprint of preterm birth with very low birth weight on optic disc OCT in adulthood-A two-country birth cohort study

PURPOSE

To determine the pattern, degree and prevalence of optic disc optical coherence tomography (OCT) alterations in adults born preterm with very low birth weight (VLBW; birth weight < 1500 g).

METHODS

Optic disc OCT was assessed in 98 VLBW participants and 139 term-born controls from birth cohorts in Finland and Norway at the mean age of 36 years. The participants had not been treated for retinopathy of prematurity and had no diagnosed brain abnormality. OCT assessment included parameters for optic disc size, neural rim and peripapillary retinal nerve fibre layer thickness (pRNFLT), and for the foveal developmental stage. Background data, visual acuity, refractive error and intraocular pressure were recorded.

RESULTS

In the VLBW group, optic disc neural rim and pRNFLT were significantly decreased, most frequently in the nasal and inferior sectors. In 40% (95% CI: 33-47) of the VLBW eyes, nerve fibre thickness of at least one optic disc sector was below the fifth percentile of the control group, including 9% (95% CI: 6-14) subgroup falling below the first percentile, that is, clinically below normal limits. VLBW participants with nerve fibre thickness below the fifth percentile did not differ by perinatal data or foveal developmental stage from the other VLBW participants. All participants had normal visual acuity.

CONCLUSION

A moderate decrease of the optic disc neural rim and pRNFLT is frequently seen in clinically healthy adults born preterm with VLBW. Awareness of the VLBW-related optic disc nerve fibre shallowness especially in the inferior and nasal sectors is important while evaluating acquired optic disc pathology in 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.

[Morphological features of an optic nerve in premature infants according to the optical coherence tomography data]

OBJECTIVE

To assess the morphological state of the visual analyzer in premature infants in long-term.

MATERIAL AND METHODS

We examined 40 premature children (74 eyes) aged 10.3±2.92 years (gestational age (GA) 25-34 weeks, birth weight (BW) 690-2700 g). Twenty mature children (40 eyes), aged 10.8±3.05 years, were examined as a control group. The children underwent standard ophthalmologic examination, optical coherence tomography (OCT) and recording of visual evoked potentials (VEP).

RESULTS

The thickness of retinal nerve fiber layer (RNFL) is less in preterm infants than in term infants, regardless of retinopathy of prematurity (ROP) and refraction (p<0.05). Thickness loss has an inverse proportion with the degree of hypoxic-ischemic encephalopathy (HIE) and intraventricular hemorrhage (IVH) (p<0.05). Retinal thickness in fovea is significantly greater in preterm infants and has a direct proportionality with the degree of IVH and the number of days on artificial lung ventilation (p<0.05). Moderate organic changes were detected in conduction pathways in 43.08% of premature infants according to VEP data.

CONCLUSION

The use of OCT and recording of VEP may improve the quality of comprehensive neuro-ophthalmologic diagnosis in preterm infants. The thickness loss of RNFL can be expected in premature infants with HIE and IVH.

Impact of preterm birth on the onset of panic disorder in later life - Results from the Gutenberg Prematurity Study (GPS)

BACKGROUND

The present study aimed to investigate whether prematurity and perinatal stress exert long-term effects on the onset of panic disorder in later life.

METHODS

From 40,189 adults born in Germany between 1969 and 2002, a study cohort (n = 427) stratified by gestational age (GA) (extremely preterm: GA < 29 weeks; very preterm: GA 29-32 weeks; moderately preterm: GA 33-36 weeks; and full-term GA ≥ 37 weeks) was selected (age 28.5 ± 8.7 years). Multivariable logistic regression analyses were conducted to investigate associations between gestational age at birth and panic disorder adjusting for age, gender, socioeconomic status, and perinatal factors.

RESULTS

The prevalence of panic disorder was roughly equal in moderate to very preterm and full-term birth groups at 1.9%-3.8%. However, this rate significantly increased to 14.3% in the extreme preterm category (GA <2 9: 14.3 %, p = 0.002). In multivariable analyses, female gender and GA were independently associated with panic disorder. Adjusting for age, gender and socioeconomic status, panic disorder was associated with lower GA at birth (OR = 1.12 per week (CI95%: 1.01-1.26, p = 0.037). Whereas adjustment for nutrition status or indicators of perinatal stress had no effect, correction for the length of postnatal ICU-stay eliminated the association between preterm birth and later panic disorder.

LIMITATIONS

Limitations include the small number of cases and the reliance on questionnaires to assess mental status.

CONCLUSIONS

Prematurity likely increases the risk of panic disorder later in life, and the subsequent postnatal ICU-stay appears to be of critical importance. However, due to strong collinearity and other associated factors with preterm births, it remains unclear which is the primary determinant.

Peripapillary Retinal Nerve Fiber Layer Thickness Changes in Preterm Children with or without Retinopathy of Prematurity History

Purpose

To investigate peripapillary retinal nerve fiber layer (pRNFL) thickness changes in preterm children with or without retinopathy of prematurity (ROP) history compared to full-term children.

Methods

A retrospective comparative cohort study assessing pRNFL thickness was completed in children aged 4-8 years. Four groups of children were included (n = 30 each group): children with a history of ROP who were treated with intravitreal bevacizumab, children with ROP who received no treatment, and preterm children without ROP compared to age- and gender-matched full-term children.

Results

A total of 120 eyes from 120 children were enrolled in this study. Both treated and regressed ROP children showed a significantly thinner pRNFL in the nasal quadrant compared to full-term children (P = 0.017 and P = 0.008, respectively). The pRNFL in the superior quadrant of treated ROP children was thinner than the preterm and control groups (P = 0.015 and P = 0.023, respectively), whereas the inferior quadrant of treated ROP children was thinner than the preterm group alone (P = 0.008). The pRNFL thickness in the temporal quadrant was comparable between groups (P = 0.129). The average spatial distribution profile of pRNFL thickness in treated ROP children was significantly thinner than in the preterm group (P = 0.041).

Conclusion

pRNFL thickness is significantly altered in children with a prior history of treated ROP with thinning of the nasal and superior quadrants compared to full-term children.

The impact of perinatal brain injury on retinal nerve fiber layer thickness and optic nerve head parameters of premature children

PURPOSE

This study aims to evaluate the impact of birth weight (BW), gestational age (GA), retinopathy of prematurity (ROP), and perinatal brain injury (PBI) on optic nerve head (ONH) parameters and nerve fiber layer thickness (RNFLT) in preterm children.

METHODS

ONH parameters and RNFLT were examined prospectively in 5-15-year-old preterm and full-term children with RTVue-100 OCT (Optovue, USA). The parameters of the two groups were compared and possible influences of BW, GA, ROP, and PBI analyzed in preterm children.

RESULTS

In total, 51 full-term and 55 preterm children were included. The mean age was 9.98 ± 3.4 years in full-term and 10.0 ± 2.5 years in preterm children. The mean GA in preterm children was 29.6 ± 3.8 weeks with a BW of 1523 ± 732 g. RNFLT was significantly lower in preterm than in full-term children in all but temporal quadrants. Cup area, volume, cup/disc area ratio, and horizontal cup/disc ratio (CDR) were significantly larger and rim area significantly thinner in preterm children. GA was positively correlated with superior, nasal, and overall RNFLT and negatively correlated with cup area, volume, and horizontal CDR. ROP stage correlated negatively with superior and nasal RNFLT. PBI was the only significant predicting factor for RNFL thinning in all but temporal quadrant in multiple regression analysis. Preterm children with PBI had a significantly larger optic cup (CDR 0.70 ± 0.33 vs. 0.37 ± 0.27) and thinner optic rim.

CONCLUSION

PBI correlated strongest with RNFL thinning, a thinner optic rim, and a larger optic cup in preterm children and should be evaluated in each patient to prevent incorrect diagnosis like glaucoma.

Normative data for macular and retinal nerve fibre layer thickness in healthy German children and adolescents using optical coherence tomography

PURPOSE

To establish normative data for macular thickness, macular volume and peripapillary retinal nerve fibre layer (RNFL) thickness using Spectralis® spectral-domain optical coherence tomography (SD-OCT) in healthy German children and adolescents and investigate influencing factors.

METHODS

The cross-sectional study included the right eye of 695 children with at least one complete retinal OCT scan. As part of the LIFE Child study, the children underwent an ophthalmological examination including axial length (AL), spherical equivalent (SE) and OCT measurements. Various questionnaires were answered by the children or their parents to identify media use or outdoor time. Multiple linear regression models were used to investigate the potential influencing factors.

RESULTS

A total of 342 boys and 353 girls with an average age (SD) of 12.91 (3.29) years participated. The mean AL (SD) was 23.20 (0.86) mm. The mean macular thickness (SD) was 320.53 (12.29) μm and the mean RNFL thickness (SD) was 102.88 (8.79) μm. Statistical analysis revealed a significant correlation between average macular thickness and age (p < 0.001, β = 0.77) as well as AL (p < 0.001, β = -4.06). In addition, boys had thicker maculae (p < 0.001, β = 5.36). The RNFL thickness showed no significant correlation with children's age (p > 0.05), but with AL (p = 0.002, β = -2.15), birth weight (p = 0.02, β = 0.003) and a gender-specific effect of the body mass index standard deviation score for male participants (p = 0.02, β = 1.93).

CONCLUSION

This study provides normative data and correlations between macular and RNFL thickness in healthy German children. Especially age, gender and AL must be taken into account when evaluating quantitative OCT measurements to classify them as normal.

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.

Peripapillary Retinal Nerve Fiber Layer Thickness in Adults Born Extremely, Very, and Moderately Preterm With and Without Retinopathy of Prematurity: Results From the Gutenberg Prematurity Eye Study (GPES)

PURPOSE

This study investigated whether prematurity and associated factors or prenatal growth restriction have long-term effects on the peripapillary retinal nerve fiber layer (pRNFL) in adulthood.

DESIGN

Retrospective cohort study.

METHODS

The Gutenberg Prematurity Eye Study (GPES) is a retrospective cohort study with a prospective ophthalmologic examination in Germany. Selected individuals born term and preterm (age 18-52 years) were examined with spectral-domain optical coherence tomography (SD-OCT) in adulthood, and perinatal medical charts were reviewed. The pRNFL thickness was measured using SD-OCT. Univariate and multivariable linear regression analyses were conducted to investigate associations between pRNFL and gestational age (GA; categorical), birth weight percentile (categorical), retinopathy of prematurity (ROP) occurrence, and treatment and other perinatal parameters with adjustment for age, sex, and spherical equivalent.

RESULTS

In total, 766 eyes of 406 preterm and full-term individuals were included (mean age 28.4 ± 8.6 years, 228 females). After adjustment for age, sex, and spherical equivalent, global pRNFL thinning was associated with moderate (GA = 33-36 wk, β = -4.68, P < .001), very (GA = 29-32 wk, β = -5.72, P < .001), and extreme (GA ≤ 28 wk, β = -8.69, P < .001) prematurity but not with low birth weight percentile (<25th percentile, P = .9) and ROP occurrence (P = .9) in multivariable analysis. ROP treatment was associated with increased pRNFL in the temporal sector (P = .002). Maternal smoking during pregnancy showed an association with pRNFL thinning (P = .07).

CONCLUSION

Our data indicate that the more preterm individuals are born the more pRNFL thinning occurs, whereas prenatal growth restriction and postnatal occurrence of ROP show less effects on pRNFL thickness. Furthermore, individuals with severe ROP with treatment but not lower ROP stages without treatment showed an increased temporal pRNFL thickness.

Peripapillary retinal nerve fibre layer thickness and macular ganglion cell layer volume in association with motor and cognitive outcomes in 11-year-old children born very preterm

PURPOSE

The purpose of the study was to study the association between retinal parameters and motor and cognitive outcomes in children born very preterm.

METHODS

This study is part of a prospective cohort study of very preterm infants (birth weight ≤ 1500 grams/gestational age < 32 weeks). At 11 years of age, the ophthalmological assessment included a retinal optical coherence tomography (OCT) examination of the peripapillary retinal nerve fibre layer (PRNFL) and the macular ganglion cell layer (GCL). The motor performance was assessed with the Movement Assessment Battery for Children-Second Edition (Movement ABC-2), and the cognitive outcome with the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV).

RESULTS

A total of 141 children were included. The mean (SD) average PRNFL was 95 μm (10.2 μm). The mean (SD) macular GCL volume was 0.34 mm³ (0.03 mm³ ). Higher PRNFL thickness associated with higher percentiles for total scores in the motor assessment (b = 0.5, 95% CI 0.1-0.8, p = 0.01) and higher macular GCL volume with higher scores in the cognitive assessment (b = 1.4, 95% CI 0.5-2.3, p = 0.002), also when adjusted for gender, birth weight z-score (birth weight in relation to gestational age) and major brain pathology at term.

CONCLUSION

The associations between higher average PRNFL thickness and better motor performance as well as higher macular GCL volume and better cognitive performance refer to more generalized changes in the brain of 11-year-old children born very preterm. Retinal OCT examinations might provide a deeper insight than mere eyesight in long-term neurodevelopmental follow-up of children born very preterm.

The Relationship Between Fetal Growth and Retinal Nerve Fiber Layer Thickness in a Cohort of Young Adults

Purpose

To explore relationships between patterns of fetal anthropometric growth, as reflective of fetal wellbeing, and global retinal nerve fiber layer (RNFL) thickness measured in young adulthood.

Methods

Participants (n = 481) from within a Western Australian pregnancy cohort study underwent five serial ultrasound scans during gestation, with fetal biometry measured at each scan. Optic disc parameters were measured via spectral-domain optical coherence tomography imaging at a 20-year follow-up eye examination. Generalized estimating equations were used to evaluate differences in global RNFL thickness between groups of participants who had undergone similar growth trajectories based on fetal head circumference (FHC), abdominal circumference (FAC), femur length (FFL), and estimated fetal weight (EFW).

Results

Participants with consistently large FHCs throughout gestation had significantly thicker global RNFLs than those with any other pattern of FHC growth (P = 0.023), even after adjustment for potential confounders (P = 0.037). Based on model fit statistics, FHC growth trajectory was a better predictor of global RNFL thickness than birth weight or head circumference at birth. RNFL thickness did not vary significantly between groups of participants with different growth trajectories based on FAC, FFL, or EFW.

Conclusions

FHC growth is associated with RNFL thickness in young adulthood and, moreover, is a better predictor than either birth weight or head circumference at birth.

Translational Relevance

This research demonstrates an association between intrauterine growth and long-term optic nerve health, providing a basis for further exploring the extent of the influence of fetal wellbeing on clinical conditions linked to RNFL thinning.

Neurosensory Alterations in Retinopathy of Prematurity: A Window to Neurological Impairments Associated to Preterm Birth

Retinopathy of prematurity (ROP) is one of the main blinding diseases affecting preterm newborns and is classically considered a vascular disorder. The premature exposure to the extrauterine environment, which is hyperoxic in respect to the intrauterine environment, triggers a cascade of events leading to retinal ischemia which, in turn, makes the retina hypoxic thus setting off angiogenic processes. However, many children with a history of ROP show persistent vision impairment, and there is evidence of an association between ROP and neurosensory disabilities. This is not surprising given the strict relationship between neuronal function and an adequate blood supply. In the present work, we revised literature data evidencing to what extent ROP can be considered a neurodegenerative disease, also taking advantage from data obtained in preclinical models of ROP. The involvement of different retinal cell populations in triggering the neuronal damage in ROP was described along with the neurological outcomes associated to ROP. The situation of ROP in Italy was assessed as well.

Association Between Retinal Microanatomy in Preterm Infants and 9-Month Visual Acuity

Importance

Preterm infants are at risk for poor visual acuity (VA) outcomes, even without retinal problems on ophthalmoscopy. Infant retinal microanatomy may provide insight as to potential causes.

Objective

To evaluate the association between preterm infant retinal microanatomy and VA at 9 months' corrected age.

Design, Setting, and Participants

This prospective observational study took place from November 2016 and December 2019 at a single academic medical center and included preterm infants enrolled in Study of Eye Imaging in Preterm Infants (BabySTEPS). Infants were eligible for enrollment in BabySTEPS if they met criteria for retinopathy of prematurity (ROP) screening, were 35 weeks' postmenstrual age or older at the time of first OCT imaging, and a parent or guardian provided written informed consent. Of 118 infants enrolled in BabySTEPS, 61 were included in this analysis. Data were analyzed from March to April 2021.

Exposures

Bedside optical coherence tomography (OCT) imaging at a mean (SD) 39.85 (0.79) weeks' postmenstrual age and monocular grating VA measurement at 9 months' corrected age.

Main Outcomes and Measures

Presence and severity of macular edema and presence of ellipsoid zone at the fovea measured by extracting semiautomated thicknesses of inner nuclear layer, inner retina, and total retina at the foveal center; choroid across foveal 1 mm; and retinal nerve fiber layer (RNFL) across the papillomacular bundle (PMB). Pearson correlation coefficients were calculated and 95% CIs were bootstrapped for the association between retinal layer thicknesses and continuous logMAR VA. Associations were analyzed between retinal microanatomy and normal (3.70 cycles/degree or greater) vs subnormal grating VA at 9 months' corrected age using logistic regression and with logMAR VA using linear regression, adjusting for birth weight, gestational age, and ROP severity at the time of OCT imaging and accounting for intereye correlation using generalized estimating equations.

Results

The mean (SD; range) gestational age of included infants was 27.6 (2.8; 23.0-34.6) weeks, and mean (SD; range) birth weight was 958.2 (293.7; 480-1580) g. In 122 eyes of 61 infants, the correlations between retinal layer thicknesses and logMAR VA were as follows: r, 0.01 (95% CI, -0.07 to -0.27) for inner nuclear layer; r, 0.19 (95% CI, 0.01 to 0.35) for inner retina; r, 0.15 (95% CI, -0.02 to 0.31) for total retina; r, -0.22 (95% CI, -0.38 to -0.03) for choroid; and r, -0.27 (95% CI, -0.45 to 0.10) for RNFL across the PMB. In multivariable analysis, thinner RNFL across the PMB (regression coefficient, -0.05 per 10-μm increase in RNFL thickness; 95% CI, -0.10 to -0.01; P = .046) and prior ROP treatment (regression coefficient, 0.33 for ROP treatment; 95% CI, 0.11 to 0.56; P = .003) were independently associated with poorer 9-month logMAR VA.

Conclusions and Relevance

In preterm infants, RNFL thinning across the PMB was associated with poorer 9-month VA, independent of birth weight, gestational age, need for ROP treatment, and macular microanatomy. Evaluation of RNFL thickness using OCT may help identify preterm infants at risk for poor vision outcomes.

Optic Nerve Head Morphology in Adults Born Extreme, Very, and Moderate Preterm With and Without Retinopathy of Prematurity: Results From the Gutenberg Prematurity Eye Study

PURPOSE

This study aimed to investigate associations of prematurity and associated factors with optic disc morphology in adulthood as long-term effects.

DESIGN

Retrospective cohort study.

METHODS

The Gutenberg Prematurity Eye Study (GPES) is a retrospective cohort study with a prospective ophthalmologic examination of adults (age 18-52 years) in Germany. In every participant, photography of optic discs was performed with a nonmydriatic fundus camera, and optic disc measurements were done manually. The vertical cup-to-disc ratio (VCDR), optic disc area, and torted and tilted discs were assessed and exploratively compared between individuals with retinopathy of prematurity (ROP) with treatment, an ROP group without treatment and groups of individuals of different gestational ages (GAs) without ROP (GA ≤ 28 weeks, GA 29-32 weeks, GA 33-36 weeks, and GA ≥ 37 weeks [control group]).

RESULTS

The present analysis included 743 eyes of 393 individuals born preterm and full-term (aged 28.4 ± 8.6 years, 223 females). The VCDR was significantly larger in subjects with a GA ≤28 weeks without ROP compared to the full-term control group (GA ≥37 weeks) (P = .002). Subjects with ROP without treatment also had a larger VCDR (P = .001), whereas those with ROP treatment showed a smaller VCDR than the full-term control group (P = .02). In addition, individuals with ROP treatment were more likely to have a torted disc than the full-term control group (P = .006).

CONCLUSION

The present study provides evidence that individuals born extremely preterm have increased VCDR in adulthood. Furthermore, these results indicate that fetal origins affect optic disc morphology until adulthood, which might predispose the affected individual to degenerative optic nerve head diseases or being incorrectly diagnosed to glaucoma.

Evaluation of Ocular Biometric and Optical Coherence Tomography Parameters in Preterm Children Without Retinopathy of Prematurity

Purpose

To evaluate and compare biometric and optical coherence tomography parameters of ocular structures in preterm children without retinopathy of prematurity with term children.

Methods

A cross-sectional, comparative study was carried out from 2018 to 2019. In this study, 124 eyes of 62 preterm children were compared with 132 eyes of 66 term children aged between 7 and 9 years. Preterm children were born at 28 to 32 weeks with a birth weight of less than 2 kg with no ocular abnormalities, and term children were delivered at 37 or greater weeks and had a birth weight of 2 kg or more. All children had standardized eye examinations, and ocular measurements using the anterior and posterior segment optical coherence tomography and laser interferometry.

Results

Significant differences were found between the term and preterm children for horizontal corneal diameter: median, 12.2 mm (interquartile range [IQR], 0.4) versus median, 12.1 mm (IQR, 0.6; P < 0.005); axial length median, 23.03 mm (IQR, 1.10 mm) versus median, 22.88 mm (IQR, 1.35 mm; P = 0.017); global retinal nerve fiber layer thickness: mean ± standard deviation, 106.54 ± 10.23 µm versus mean ± standard deviation, 103.65 ± 10.178 µm (P = 0.024); temporal retinal nerve fiber layer thickness: median, 76 µm (IQR, 16 µm) vs median, 74 µm (IQR, 14 µm; P = 0.012); and the angle opening distance at 750 µm nasal: mean ± standard deviation, 0.815 ± 0.23 mm vs mean ± standard deviation, 0.749 ± 0.21 mm (P = 0.016). No significant differences were found for other anterior segment and angle parameters.

Conclusions

Preterm children with no retinopathy of prematurity have smaller eyes and thinner retinal nerve fiber layers than their term counterparts. The long-term effects of interrupted ocular growth in preterm children should be further studied into adulthood.

Translational Relevance

Preterm children maybe more predisposed to certain eye conditions because they have smaller eyes, and thus should be further monitored clinically.

The impact of moderate-to-late prematurity on ocular structures and visual function in Saudi children

Aim

To assess and compare ophthalmologic and morphologic outcomes between school-age children born moderate-to-late preterm and those born at term.

Patients and Methods

Fifty children born moderate-to-late preterm (gestational age 32 weeks + 0 days to 36 + 6 days, age range 5-10 years) at a tertiary university hospital were age- and sex-matched to full-term controls. Visual acuity, refractive errors, ocular biometry, macular, and optic nerve assessments with optical coherence tomography were investigated and compared between cases and controls.

Results

No differences in visual acuity or refraction were detected between the study groups. The difference in refractive error was not significant between the groups. Marked differences were observed in the anterior chamber depth, which was shallower in the preterm group (P = 0.044); however, no difference in total axial length was observed. The preterm and control groups significantly differed in terms of central macular thickness (247 ± 19 μm versus 235 ± 22 μm; P = 0.005 right eye); however, the groups did not significantly differ in foveal thickness. Central subfield thickness was also markedly greater in the preterm than in the control children (246.89 ± 19.1 μm versus 236.12 ± 23.3 μm, P = 0.015). No significant differences in mean parafoveal/perifoveal thicknesses or optic nerve parameters were observed between both groups.

Conclusion

Significant differences between moderate to late preterm and full-term groups in regards to anterior chamber depth, central macular thickness, and central subfield thickness were found. It is important to recognize that being born preterm might have an impact on some ocular structures. Larger population-based studies should be conducted to study the long-term sequelae of moderate-to-late prematurity in our children.

[Impact of prematurity on the optic nerve]

INTRODUCTION

Thanks to the progress made in the past few years in pediatric intensive care as well as the increased survival of preterm infants, the consequences of premature birth are increasingly well documented. With regard to ophthalmologic complications, retinopathy of prematurity is well described, but the optic nerve may also be affected. The goal of this study is to compare the optic nerves of preterm infants as a function of their gestational period with a control group of the same age.

MATERIALS AND METHODS

We conducted a case-control study pairing a full-term infant with each preterm infant. Inclusion criteria were: any child from 5- to 10-years-old, separated into three sub-groups according to their degree of prematurity. Variables were: cup/disc ratio, ocular biometry, intraocular pressure and RNFL thickness.

RESULTS

Thirty-seven preterm infants and 37 controls were included in the study. The mean age at the time of inclusion was 7.05 years for the preterm group and 7.19 years for the control group. No significant difference was observed in axial length or spherical equivalent (P=0.31 and P=0.98, respectively). No significant difference was observed in pachymetry or intraocular pressure (P=0.28 and P=0.22, respectively). We observed a significant increase of 0.1 in the cup/disc ratio of the preterm group compared to the control group (P<0.05). The preterm group cup/disc ratio was 0.36 versus 0.27 for the control group. No significant difference was observed in the 7 quadrants of RNFL between the two groups. However, when comparing infants born before 28 weeks gestation with the control group, we observed a mean decrease of 14.5 microns in the superior temporal sector (P=0.04), a 9 micron decrease in the global thickness G (P=0.03) and a 12.7 micron decrease in the nasal sector (P=0.01).

CONCLUSIONS

In the case of the studied children (aged 5 to 10), the reduced RNFL fiber thickness is a phenomenon dependent essentially on the stage of prematurity. It would be useful to follow these preterm populations over the long term and to compare them to a matched control group to be able to obtain functional results.

Association of Birth Weight with Peripapillary Retinal Nerve Fiber Layer Thickness in Adulthood—Results from a Population-Based Study

Purpose

Low birth weight is associated with altered retinal development in childhood, including reduced peripapillary retinal nerve fiber layer (pRNFL) thickness. However, to the best of our knowledge, no population-based study has analyzed the relationship of low birth weight to pRNFL thickness in adulthood. The purpose of this study was to investigate whether birth weight has a long-term effect on pRNFL thickness in adulthood.

Methods

In the German population-based Gutenberg Health Study (GHS), participants were examined with spectral-domain optical coherence tomography using a peripapillary scan and automated measurement of pRNFL thickness as a global parameter and in six sectors. The association between self-reported birth weight and the different pRNFL sectors were analyzed with multivariable linear regression, adjusted for potential confounders including sex, age, axial length, self-reported age-related macular degeneration, and glaucoma.

Results

In 3,028 participants, self-reported birth weight was documented and pRNFL measurements were successfully performed (1632 females, ages 54.9 ± 10.0 years). After adjustment for several confounders in the multivariable model, a positive association was observed between birth weight and pRNFL thickness in the global sector (β = 0.13 µm/100 g; 95% CI, 0.08–0.18; P < 0.001; R² = 0.007) and especially in the inferotemporal sector (β = 0.22 µm/100 g; 95% CI, 0.15–0.29; P < 0.001; R² = 0.008) and inferonasal sector (β = 0.28 µm/100 g; 95% CI, 0.17–0.39; P < 0.001; R² = 0.005).

Conclusions

Our data show that there is a weak relationship between birth weight and pRNFL thickness in adulthood. This weak association is particularly present in the inferior part of the optic nerve head. Therefore, low birth weight may have an impact on optic nerve head development and potentially on ocular disease development.

Periventricular Leukomalacia in Patients With Pseudo-glaucomatous Cupping

PURPOSE

Periventricular leukomalacia (PVL) is a structural loss of white matter pathways that carry visual information from the lateral geniculate bodies to the visual cortex. It is observed radiologically in patients with a history of prematurity and is associated with visual field (VF) defects and optic disc cupping. Advances in perinatal care have improved survival for premature babies, so many now present as adolescents and adults to comprehensive eye doctors who are unaware of the relationship of cupping, field defects, and prematurity and who may diagnose manifest or suspected normal tension glaucoma. We describe 2 such patients to raise awareness of this entity.

DESIGN

Case series.

METHODS

Review of clinical information of 2 patients identified during clinical practice. Charts were reviewed for gestational age, optic nerve appearance, intraocular pressure (IOP), and sequelae of prematurity. Magnetic resonance imaging (MRI), optical coherence tomography (OCT), VF, and optic disc photographs were reviewed.

RESULTS

Two young patients with a history of prematurity presented with enlarged cup-to-disc ratio and normal IOP. OCT thinning was most prominent superiorly, with VF defects more notable inferior and homonymous. No progression on VF or OCT was noted in the index case over almost 4 years.

CONCLUSIONS

Periventricular leukomalacia should be added to the differential diagnosis of normal tension glaucoma (NTG) when there is a history of prematurity. Careful examination of the optic nerve will assist in differentiating from NTG. Specifically, horizontal cupping with minimal or no nasal displacement of vessels, and superior optic nerve thinning with inferior VF defects, suggest PVL.

Quantitative analysis of retinal microcirculation in children with hyperopic anisometropic amblyopia: an optical coherence tomography angiography study

PURPOSE

To evaluate optical coherence tomographic angiography (OCTA) findings on retinal microcirculation in hyperopic anisometropic amblyopia compared with fellow eyes and nonamblyopic control eyes.

METHODS

A total of 40 pediatric patients with hyperopic anisometropic amblyopia and 57 control subjects were recruited, and 137 eyes (40 amblyopic, 40 fellow, and 57 control eyes) were evaluated. Data on best-corrected visual acuity (logMAR), axial length (mm), refractive error, and OCTA findings (foveal avascular zone parameters, macular vascular density in superficial and deep retinal capillary plexus, central macular thickness) were recorded in amblyopic, fellow, and control eyes.

RESULTS

Compared with fellow and control eyes, amblyopic eyes were associated with significantly lower foveal vessel density values within 300 μm around the foveal avascular zone (P < 0.01) and lower vascular density in certain areas of superficial and deep retinal capillary plexus in axial length- and refraction-adjusted analysis (P < 0.05 for all), along with significantly higher full thickness of the central macula (P = 0.04). In amblyopic eyes, best-corrected visual acuity values were negatively correlated with foveal density (r = -0.57; P = 0.02) and deep capillary retinal plexus vascular density in foveal (r = -0.51; P = 0.03) parafovea temporal (r = -0.52; P = 0.03), and parafovea superior (r = -0.51; P = 0.04) areas.

CONCLUSIONS

Our findings indicate a possible association between retinal microcirculation and amblyopia.

INCREASED FOVEAL GANGLION CELL AND INNER PLEXIFORM LAYER THICKNESS IN CHILDREN AGED 6.5 YEARS BORN EXTREMELY PRETERM

PURPOSE

To analyze the ganglion cell layer and inner plexiform layer (GCL+) thickness in children born extremely preterm and control children.

METHODS

A study of 6.5-year-old children born before the gestational age of 27 weeks and age-matched controls. The GCL+ thickness and foveal depth (FD) were analyzed in a single optical coherence tomography B-scan. Association with neonatal risk factors and sex was investigated. Extremely preterm was divided into no, mild, and severe retinopathy of prematurity, retinopathy of prematurity treatment, and no, mild, and severe intraventricular hemorrhage.

RESULTS

Adequate measurements were obtained from 89 children born extremely preterm and 92 controls. Extremely preterm children had increased total (5 µm, P < 0.001) and central (21 µm, P < 0.001) GCL+ thickness and reduced FD (-53 µm, P < 0.001) compared with controls. Extremely preterm children receiving retinopathy of prematurity treatment had increased GCL+ thickness and reduced FD compared with other subgroups. Sex and gestational age were associated with increased central GCL+ thickness and reduced FD. Reduced total GCL+ thickness was associated with severe intraventricular hemorrhage.

CONCLUSION

Extremely preterm birth can cause incomplete extrusion of the GCL+ and reduced FD. Retinopathy of prematurity treatment, gestational age, and male sex were associated to increased central GCL+ thickness and reduced FD, while severe intraventricular hemorrhage was associated with reduced total GCL+ thickness.

Correlation of morphological parameters and visual acuity with neurological development in former preterm children aged 4-10 years

PURPOSE

The objective of this study was to investigate the relationship between visual acuity, peripapillary retinal nerve fibre layer (pRNFL), retinal thickness at the fovea and other factors with the neurologic status of former preterm children.

METHODS

In this cross-sectional hospital based study in a maximum care tertiary centre, detailed anthropometric and ophthalmological data of former preterm children ranging from 4 to 10 years of age with a gestational age (GA) ≤32 weeks were assessed. Analyses of the correlation between pRNFL and foveal thickness, as well as visual acuity (VA) parameters at 4-10 years of age, with neurological development were evaluated at 2 years of age by Bayley Scales II of Infant Development, including Psychomotor Developmental Index (PDI) and Mental Developmental Index (MDI).

RESULTS

Data were available for 106 former preterm children. Univariate analysis revealed a correlation between PDI with pRNFL thickness (B = 0.43; p = 0.013), VA (B = -29.2; p < 0.001), GA (B = 2.7; p = 0.002), retinopathy of prematurity (ROP; B = -16.3; p < 0.001) and intraventricular haemorrhages (IVH; B = -22.9; p < 0.001) but not with strabismus or foveal thickness. In the multivariable analysis, the association remained for visual acuity and IVH, but not for pRNFL thickness or ROP. Mental Developmental Index (MDI) was associated with visual acuity (B = -34.3; p = 0.001), GA (B = 2.53; p = 0.02) and IVH (B = -15.4; p = 0.02), the latter also in the multivariable analysis.

CONCLUSION

This study revealed an association between PDI at 2 years of age and lower visual acuity later in childhood. However, there was no correlation between retinal morphology and neurologic outcome in former preterm children after adjusting for several potential confounders.

Retinal Parameters as Compared with Head Circumference, Height, Weight, and Body Mass Index in Children in Kenya and Bhutan

The retina shares embryological derivation with the brain and may provide a new measurement of overall growth status, especially useful in resource-limited settings. Optical coherence tomography (OCT) provides detailed quantification of retinal structures. We enrolled community-dwelling children ages 3–11 years old in Siaya, Kenya and Thimphu, Bhutan in 2016. We measured head circumference (age < 5 years only), height, and weight, and standardized these by age and gender. Research staff performed OCT (iScan; Optovue, Inc., Fremont, CA), measuring the peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC) thicknesses. A neuro-ophthalmologist performed quality control for centration, motion artifact, and algorithm-derived quality scores. Generalized estimating equations were used to determine the relationship between anthropometric and retinal measurements. Two hundred and fifty-eight children (139 females, average age 6.4 years) successfully completed at least one retinal scan, totaling 1,048 scans. Nine hundred and twenty-two scans (88.0%) were deemed usable. Fifty-three of the 258 children (20.5%) were able to complete all six scans. Kenyan children had a thinner average GCC (P < 0.001) than Bhutanese children after adjustment for age and gender, but not RNFL (P = 0.70). In models adjusting for age, gender, and study location, none of standardized height, weight, and body mass index (BMI) were statistically significantly associated with RNFL or GCC. We determined that OCT is feasible in some children in resource-limited settings, particularly those > 4 years old, using the iScan device. We found no evidence for GCC or RNFL as a proxy for height-, weight-, or BMI-for-age. The variation in mean GCC thickness in Asian versus African children warrants further investigation.

The inner retinal structures of the eyes of children with a history of retinopathy of prematurity

PurposeTo investigate the microstructural differences of the inner retina in the peripapillary and macular areas in children with or without retinopathy of prematurity (ROP).MethodsThis prospective cohort study included school-age children with a history of ROP and age-matched healthy, full-term children. The macular ganglion cell complex (mGCC), peripapillary retinal nerve fiber layer (RNFL), refractive status, and ocular biometry were measured. The metrics of the mGCC and associated anatomical changes were the primary outcomes. Mann-Whitney U tests and chi-squared tests were used to compare variables between the two groups.ResultsA total of 41 eyes from 21 preterm children with ROP and 34 eyes from 17 full-term children were enrolled. ROP eyes had significantly thicker mGCC (P<0.001) with uneven distribution compared with full-term eyes. The RNFLs of ROP eyes were thicker in the temporal quadrants but thinner in the nasal quadrants (P=0.01 and.04, respectively). In addition, the ROP eyes had shallower anterior chamber depths (ACDs), thicker lenses, and higher degrees of refractive errors (all P<0.05) but similar axial lengths (ALs) (P=0.58) compared with full-term eyes.ConclusionsThe mGCC was thicker in children with ROP, and their inner retinal structures had a different distribution pattern than those in full-term children. The myopia of children with ROP was associated with the abnormal development of the anterior segment rather than long ALs. These alterations in inner retinal anatomy and optic components emphasize the importance of careful examinations to monitor the development of glaucoma or visual decline in children with ROP.

Macular morphology in former preterm and full-term infants aged 4 to 10 years

OBJECTIVE

To analyse macular retinal and choroidal layer thickness in former preterm and full-term infants and to assess associated perinatal influence factors and functional correlation.

METHODS

This prospective controlled, cross-sectional, hospital-based study in a tertiary center of maximum care examined former preterm infants with a gestational age (GA) ≤ 32 weeks and full-term neonates currently aged 4 to 10 years. We investigated data from 397 infants, analysing total foveal retinal thickness and six distinct macular retinal layer and choroidal layer measurements via spectral-domain optical coherence tomography. Multivariable linear regression analysis was performed to investigate associations of layer thickness with GA and retinopathy of prematurity (ROP).

RESULTS

Total retinal thickness in the fovea was thicker in former preterm infants with GA ≤ 28 weeks and in those with GA between 29-32 weeks compared to full-term infants independently of ROP. Occurrence of ROP was also associated with increased foveal thickness. Ganglion cell layer together with inner plexiform layer (GCL+IPL) was thinner in infants with GA ≤ 28 weeks than in full-term infants at 1000 and 2000μm distance from the fovea, but no association with ROP was present. Similar results were found for the photoreceptor layer. Total foveal retinal thickness was associated with low visual function.

CONCLUSION

This study identified low gestational age and ROP occurrence as main determinants for foveal thickening. Furthermore, thinned GCL+IPL measurements were associated with lower gestational age. This study highlights the prognostic value of these maturity parameters influencing retinal morphology, which may affect visual function.

Ocular morphology and visual function in relation to general growth in moderate-to-late preterm school-aged children

PURPOSE

To study ocular morphology and visual function in relation to general growth in moderate-to-late preterm (MLP) children.

METHODS

Visual acuity (VA), refraction, optic disc parameters, biometric values and anthropometric measures were obtained from 50 eight-year-old MLP and 43 full-term children. Macular parameters were examined by optical coherence tomography. Serum insulin-like growth factor I (IGF-I) levels were analysed at birth and at assessment and delta IGF-I was calculated.

RESULTS

Total macular volume was significantly less in MLP than in controls (both eyes p < 0.01). Macular volume correlated with head circumference (HCF) at assessment [right eye (RE) p = 0.002, r = 0.67; left eyes (LE) p = 0.01, r = 0.54] and refraction (both eyes p < 0.05, r = 0.4) in the MLP children. Furthermore, central retinal thickness correlated significantly with delta IGF-I (RE p = 0.03, r = -0.51, LE p = 0.006, r = -0.59) and refraction (both eyes p < 0.01, r = 0.5) and optic disc areas correlated with weight and height at assessment (all p < 0.05, r = 0.4). Total axial length correlated with HCF at assessment (both eyes p < 0.01, r = 0.5) and VA logMAR (both eyes p < 0.02, r = -0.4).

CONCLUSIONS

Macular volume was significantly less in MLP children than in controls examined at 8 years of age. General growth of children and IGF-I levels seem to be involved in development of ocular growth and morphology.

The range of peripapillary retinal nerve fibre layer and optic disc parameters, in children aged up to but not including 18 years of age who were born prematurely: protocol for a systematic review

BACKGROUND

The parameters of the optic disc and peripapillary retinal nerve fibre layer (pRNFL) in premature 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.

METHODS

A systematic review of current literature on the range of pRNFL and optic disc parameters in children aged less than 18 years, who were born before 37 weeks gestation, will be performed. The bibliographic databases MEDLINE, CINAHL, EMBASE, Scopus and Web of Science will be systematically searched. Where possible and appropriate, study-specific estimates will be combined using meta-analysis to obtain an overall summary estimate of pRNFL thickness and cup-disc ratio across studies, and results will be presented by age of population.

DISCUSSION

This review aims to improve understanding of what might be considered within/outside the range of normality for this high-risk group.

SYSTEMATIC REVIEW REGISTRATION

The review is registered on

PROSPERO

CRD42016037933.

Optical coherence tomography of the preterm eye: from retinopathy of prematurity to brain development

Preterm infants with retinopathy of prematurity are at increased risk of poor neurodevelopmental outcomes. Because the neurosensory retina is an extension of the central nervous system, anatomic abnormalities in the anterior visual pathway often relate to system and central nervous system health. We describe optical coherence tomography as a powerful imaging modality that has recently been adapted to the infant population and provides noninvasive, high-resolution, cross-sectional imaging of the infant eye at the bedside. Optical coherence tomography has increased understanding of normal eye development and has identified several potential biomarkers of brain abnormalities and poorer neurodevelopment.

Thinner Retinal Nerve Fiber Layer in Very Preterm Versus Term Infants and Relationship to Brain Anatomy and Neurodevelopment

PURPOSE

To assess retinal nerve fiber layer (RNFL) thickness at term-equivalent age in very preterm (<32 weeks gestational age) vs term-born infant cohorts, and compare very preterm infant RNFL thickness with brain anatomy and neurodevelopment.

DESIGN

Cohort study.

METHODS

RNFL was semi-automatically segmented (1 eye per infant) in 57 very preterm and 50 term infants with adequate images from bedside portable, handheld spectral-domain optical coherence tomography imaging at 37-42 weeks postmenstrual age. Mean RNFL thickness was calculated for the papillomacular bundle (-15 degrees to +15 degrees) and temporal quadrant (-45 degrees to +45 degrees) relative to the fovea-optic nerve axis. Brain magnetic resonance imaging (MRI) scans clinically obtained in 26 very preterm infants were scored for global structural abnormalities by an expert masked to data except for age. Cognitive, language, and motor skills were assessed in 33 of the very preterm infants at 18-24 months corrected age.

RESULTS

RNFL was thinner for very preterm vs term infants at the papillomacular bundle ([mean ± standard deviation] 61 ± 17 vs 72 ± 13 μm, P < .001) and temporal quadrant (72 ± 21 vs 82 ± 16 μm, P = .005). In very preterm infants, thinner papillomacular bundle RNFL correlated with higher global brain MRI lesion burden index (R(2) = 0.35, P = .001) and lower cognitive (R(2) = 0.18, P = .01) and motor (R(2) = 0.17, P = .02) scores. Relationships were similar for temporal quadrant.

CONCLUSIONS

Thinner RNFL in very preterm infants relative to term-born infants may relate to brain structure and neurodevelopment.

Retinal nerve fiber layer thickness in prematurity is correlated with stage of retinopathy of prematurity

PURPOSE

To compare retinal nerve fiber layer (RNFL) thickness profiles between preterm and full-term children and to investigate factors affecting the RNFL distribution in preterm children.

METHODS

We performed Spectral domain optical coherence tomography (SD-OCT) peripapillary RNFL circular scan centered on the optic disc in 50 premature and 58 full-term children. RNFL thickness profiles were compared between preterm and full-term children using a linear regression model. Among preterm patients in this study, 20 patients previously received laser treatment for severe retinopathy of prematurity (ROP).

RESULTS

Global average, nasal, and superior disc RNFL thickness profiles were significantly smaller in preterm children (92.70±16.57 μm, 56.02±17.04 μm, and 108.74±27.36 μm, respectively) compared with full-term children (101.63±9.21 μm, P=0.006, 69.14±14.15 μm, P<0.001, and superior, 129.11±18.14 μm, P<0.001, respectively). Multivariable analysis revealed that ROP stage was inversely correlated with nasal RNFL thickness (P=0.010).

CONCLUSIONS

Our SD-OCT data demonstrate decreased global average, nasal, and superior disc RNFL thicknesses in preterm children. ROP stage was inversely correlated with nasal RNFL thickness. Further studies are needed to better understand the association between these structural changes and visual functions in preterm children.

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.

The assessment of anterior and posterior ocular structures in hyperopic anisometropic amblyopia

Background

The aim of this study was to examine the relationship or differences in ocular structures of amblyopic eyes compared to fellow eyes in children and young adults with hyperopic anisometropic amblyopia.

Material/Methods

Hyperopic participants with anisometropic amblyopia, defined as the presence of best-corrected visual acuity differences of at least 2 Snellen lines and 1.5 diopters between amblyopic and fellow eyes, were studied. Using the IOL Master, Pentacam Scheimpflug imaging and Spectralis optical coherence tomography, the axial length, corneal curvature, and anterior chamber depth (ACD), as well as the thickness of the cornea, peripapillary retinal nerve fiber layer (RNFL), and macula, were compared between children and young adults and between their amblyopic and fellow eyes.

Results

In 53 participants with hyperopic anisometropic amblyopia, there were significant differences in the anterior corneal curvature, ACD and axial length between the amblyopic and fellow eyes of all the patients. The mean central macular thickness in the amblyopic eyes was significantly thicker (P=.001) in the group aged 5 to 12 years; however, this was not the case in the group aged 13 to 42 years. There was no significant difference in average RNFL thickness in either group.

Conclusions

We found significantly greater mean central macular thickness in anisometropic amblyopic eyes among participants aged 5 to 12 years, but not among those who were older. Similarly, the interocular differences in axial length parameters seemed to be related to the central macular thickness differences between the amblyopic and fellow eyes in the younger group.

Assessment of retinal nerve fiber layer thickness in healthy, full-term neonates

PURPOSE

To measure average retinal nerve fiber layer (RNFL) thicknesses in healthy, full-term neonates.

DESIGN

Descriptive research to develop normative data.

METHODS

Healthy infants born between 37 and 42 weeks postmenstrual age were imaged with hand-held spectral-domain optical coherence tomography. A custom script segmented the RNFL; the fovea and optic nerve center were manually selected. A second script measured the average RNFL thickness along the papillomacular bundle, defined as the arc from -15 degrees to +15 degrees on the axis from the optic nerve to fovea, with radii of 1.1, 1.3, 1.5, and 1.7 mm from the center of the optic disc. Shapiro-Wilk W tests assessed these measurements for normality to determine the age-appropriate radial distance for subsequent analyses. Average RNFL thicknesses for four temporal 45-degree sectors (superior temporal, temporal superior, temporal inferior, and inferior temporal) and the temporal quadrant were calculated and compared to demographic parameters for all infants.

RESULTS

Fifty full-term infants were adequately imaged for RNFL analysis. RNFL thicknesses at 1.5 mm radial distance from the optic nerve were the most normally distributed. While there was a trend toward greater mean superior temporal RNFL thickness for both black and Hispanic vs white infants (128 ± 27 μm, 124 ± 30 μm, and 100 ± 19 μm, respectively, P = .04 for both comparisons), there were no other significant differences noted in RNFL thicknesses by race, sex, gestational age, or birth weight.

CONCLUSIONS

We present RNFL thickness measurements for healthy, full-term infants that may serve as normative data for future analyses.

Microstructural changes in the retina related to prematurity

PURPOSE

To assess retinal morphology changes in patients born at different stages of prematurity, accounting for the presence or absence of retinopathy of prematurity (ROP) and comorbidity, using spectral-domain optical coherence tomography (SD OCT).

DESIGN

Retrospective cohort study.

METHODS

Preterm and term infants underwent an ophthalmologic assessment (best-corrected visual acuity, stereoacuity, cycloplegic refraction and funduscopy). Retinal layers were imaged, segmented, and measured by SD-OCT. In total 114 full term controls and 60 preterm children, classified as late preterm (32-36 weeks gestational age), early preterm (<32 weeks of gestational age) without ROP, and early preterm with previously treated ROP, were included in the study.

RESULTS

No retinal structure differences were observed in preterm infants with no treated ROP compared to term infants. Early preterm infants with previous treated ROP had decreased retinal nerve fiber layer (RNFL) thickness in the superior and nasal quadrants, increased RNFL in the temporal quadrant, and a thinner ganglion cell and inner plexiform layer complex (GCL-IPL). Low birthweight percentile was associated with increased foveal thickness and ganglion cell damage (RNFL and GCL-IPL) independent of gestational age. Among all the coexisting events, inflammation and hypoxia were correlated with more severe detrimental effects.

CONCLUSIONS

In the absence of treated ROP, prematurity was not associated with disturbed retinal structure. Severe ROP and low birthweight were related to neuronal and axonal damage in the inner retinal layers. Detailed comorbidity should be reviewed when evaluating preterm infants.

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.