Ophthalmic impairment at 7 years of age in children born very preterm

Preterm-born children, screen time, and spectacle wear in the Longitudinal Preterm Outcome Project: a cohort study

Introduction

Preterm born children are at a higher risk for refractive errors. A long duration of screen time and activities with short working distance (≤30 cm) may further add to the increased risk. The aim of this study was to assess the separate and combined effects of preterm birth and screen time on spectacle wear among 5-year-olds and adolescents.

Methods

We analyzed data from the community-based preterm cohort study, part of the Longitudinal Preterm Outcome Project (LOLLIPOP). Early preterm-born (EP < 32 weeks), moderately-late preterm-born (MLP 32-36 weeks) and full-term born (FT 38-42 weeks) children were followed. Spectacle wear and screen time were assessed by questionnaire at the age of 5 (n = 1,515) and at adolescence, ages 13-16, for a subsample (n = 227).

Results

At age 5, the prevalences of spectacle wear were 7.8%, 7.6% and 3.2%, for EP, MLP, and FT children, respectively (p = 0.007); the risk of spectacle wear decreased by 7% for each additional week of gestational age. In adolescence, prevalences were 36.6%, 20.8% and 22.4%, for EP, MLP, and FT children, respectively (p = 0.12). We found no relationship between screen-time and spectacle wear or a combined effect with preterm birth at age 5 or adolescence.

Conclusions

EP and MLP children have a significantly increased risk of spectacle wear at age 5, but not significantly at adolescence. At that age, the prevalences of spectacle wear were generally higher. We found no evidence for an association of screen time preterm birth with spectacle wear, and neither an impact of screentime on such an association.

The Effect of High-Dose Erythropoietin Perinatally on Retinal Function in School-Aged Children Born Extremely or Very Preterm

PURPOSE

To investigate the long-term effects of high-dose recombinant human erythropoietin (rhEPO) administered during the perinatal period on retinal and visual function in children born extremely or very preterm.

DESIGN

Randomized, double-blind clinical trial follow-up plus cohort study.

METHODS

 Setting: Department of Ophthalmology, University Hospital Zurich, Zurich, Switzerland.

STUDY POPULATION

Extremely or very preterm-born children aged 7 to 15 years, previously randomized to receive either high-dose rhEPO or placebo in the perinatal period.

INCLUSION CRITERIA

participation in an ongoing neuropediatric study (EpoKids), written informed consent.

EXCLUSION CRITERIA

previous ocular trauma or surgery; retinal or developmental disease unrelated to prematurity. Healthy control (HC) children of comparable age were recruited.

INCLUSION CRITERIA

term birth, informed consent.

EXCLUSION CRITERIA

any ocular/visual abnormality, high refractive error. Intervention status (rhEPO/placebo) was unknown to examiners and subjects at examination, with examiners unblinded only after completion of all analyses.

OBSERVATION PROCEDURES

The electroretinogram (ERG) was performed with the RETeval device (LKC Technologies, Inc). Ophthalmological and orthoptic examinations excluded comorbidity in the prematurely born cohort and ocular diseases in the HC group.

MAIN OUTCOME MEASURES

Scotopic and photopic ERG response amplitudes and peak times (6 amplitudes; 6 peak times). Secondary outcomes were habitual visual acuity and color discrimination performance (for descriptive summary only).

RESULTS

No differences in ERG parameters between EPO (n = 52; 104 eyes) and placebo (n = 35; 70 eyes) subgroups were observed (all corrected P > .05). Two cone system-mediated peak times were slightly slower in the placebo than HC (n = 52; 104 eyes) subgroup (coefficient/95% confidence interval = 0.53/0.21-0.85 and 0.36/0.13-0.60; P = .012 and .022); a predominantly rod system-mediated peak time was slightly faster in the EPO than the HC subgroup (coefficient/95% confidence interval = -4.33/-6.88 to -1.78; P = .011). Secondary outcomes were comparable across subgroups.

CONCLUSIONS

Administration of high-dose rhEPO to infants born extremely or very preterm during the perinatal period has no measurable effects on retinal function in childhood compared to placebo. Premature birth may cause small, likely clinically insignificant effects on retinal function in childhood, which may be partially mitigated by administration of rhEPO during the perinatal period.

A comparative study of stereopsis in term and preterm children with and without retinopathy of prematurity

PURPOSE

To evaluate stereopsis in term-born, preterm, and preterm children with and without retinopathy of prematurity (ROP) and its treatment.

METHODS

The cross-sectional study included 322 children between 3 and 11 years of age born term or preterm, with or without ROP, and with or without treatment for ROP. The ROP treatments were laser therapy, intravitreal injection (IVI) of anti-vascular endothelial growth factor, or their combination. Stereoacuity was measured using the Titmus Stereo Test, and the results among various age groups were analyzed.

RESULTS

Stereopsis was found to improve with increasing age at testing (P < 0.001) across the entire study population. The term group exhibited significantly better stereoacuity than the preterm group (P < 0.001). At 3-5 years and 6-8 years, the preterm children without ROP exhibited significantly better stereoacuity than did those with ROP (P < 0.001 and P = 0.02, respectively); however, at 9-11 years, both groups exhibited similar stereoacuity (P = 0.34). The stereoacuity in the children with untreated ROP was similar to that of the children with treated ROP in all age groups (P > 0.05). No significant differences in stereopsis were identified between children with ROP treated with laser versus with IVI (P > 0.05). From multivariate analysis, younger age at testing (P = 0.001) and younger gestational age (P < 0.001) were associated with poorer stereopsis.

CONCLUSIONS

Stereopsis development gradually improved with age in all groups. The children born preterm exhibited poorer stereoacuity than those born term. Children with ROP treated with laser photocoagulation versus IVI may exhibit similar levels of stereoacuity. Younger age at testing and gestational age were independent risk factors for poorer stereoacuity.

Relations between Neurocognitive Function and Visual Acuity: A Cross-Sessional Study in a Cohort of Premature Children

BACKGROUND

Premature children with retinopathy of prematurity (ROP) have been reported to an have increased risk of visual and neurocognitive impairments, yet little is known about whether vision could affect specific neurocognition. This study aimed to clarify the correlations between neurocognition and vision in premature children.

MATERIALS AND METHODS

This is a nonrandomized, cross-sectional, observational study in a pediatric cohort with five groups: (1) full-term (n = 25), (2) prematurity without ROP (n = 154), (3) prematurity with ROP but without treatment (n = 39), (4) prematurity with ROP and with bevacizumab (IVB) treatment (n = 62), and (5) prematurity with ROP and with laser/laser + IVB treatment (n = 20). Neurocognitive function was evaluated by the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV) around the age of 4 years. Visual acuity (VA) and refractive errors were tested. Correlations between WPPSI parameters and visual outcomes were analyzed across five groups.

RESULTS

Among the 300 recruited children (mean age = 4.02 + 0.97 years, male = 56.3%), 297 were assessed by WPPSI-IV and 142 were assessed by vision tests. The Full-Scale Intelligence Quotient (FSIQ) index was worse in the premature groups. After adjusting for covariates, seven items, including FSIQ-Index (p = 0.047), fluid-reasoning index (p = 0.004), FR-percentile ranking (p = 0.008), object assembly (p = 0.034), picture concept (p = 0.034), zoo locations (p = 0.014) and bug search (p = 0.020), showed significant differences between groups. The better the best corrected VA (BCVA), the higher the scores on Verbal Comprehension Index (VCI), VCI-PR, and the subtest of information.

CONCLUSIONS

Specific cognitive dysfunctions are related to the BCVA in this large cohort. Subtest performance profiles in WPPSI can be affected by prematurity, ROP treatment, and different ROP treatment. FSIQ is generally lower in premature children and even lower in children with ROP.

Associations between neonatal nutrition and visual outcomes in 7-year-old children born very preterm

PURPOSE

There is uncertainty about the effect of increased neonatal protein intake on neurodevelopmental outcomes following preterm birth. The aim of this study was to assess the effect of a change in neonatal nutrition protocol at a major tertiary neonatal intensive care unit intended to increase protein intake on ophthalmic and visual development in school-age children born very preterm.

METHODS

The study cohort comprised children (n = 128) with birthweight <1500 g or gestational age < 30 weeks born at Auckland City Hospital before (OldPro group, n = 55) and after (NewPro group, n = 73) a reformulation of parenteral nutrition that resulted in increased total protein intake during the first postnatal week and decreased carbohydrate, total parenteral fluid and sodium intake. Clinical and psychophysical vision assessments were completed at 7 years' corrected age, including visual acuity, global motion perception (a measure of dorsal stream function), stereoacuity, ocular motility and ocular health. Composite measures of favourable overall visual, binocular and functional visual outcomes along with individual vision measures were compared between the groups using logistic and linear regression models.

RESULTS

Favourable overall visual outcome did not differ between the two groups. However, global motion perception was better in the NewPro group (p = 0.04), whereas the OldPro group were more likely to have favourable binocular visual outcomes (60% vs. 36%, p = 0.02) and passing stereoacuity (p = 0.02).

CONCLUSIONS

These results indicate subtle but complex associations between early neonatal nutrition after very preterm birth and visual development at school age.

Prevalence and causes of ocular disorders and visual impairment among preterm children in Ethiopia

OBJECTIVE

The aim of this study was to determine the prevalence, causes of ocular disorders and visual impairment among preterm children previously admitted to neonatal intensive care units in Addis Ababa, Ethiopia.

METHODS AND ANALYSIS

A prospective screening survey was conducted from February to June 2019 at the paediatric eye clinic of Menelik II Hospital. Children who were preterm at birth and who attended the eye clinic were included in the study. Data on demographic and neonatal characteristics, neonatal and maternal comorbidities and ocular disorders were collected. OR and univariate analysis were used to identify predictors of ocular diseases and visual impairment.

RESULTS

There were 222 children included in the study with a mean age at presentation of 2.62 years (range 2.08-6.38 years), mean gestational age 34.11 weeks (range 30-36) weeks and mean birth weight 1941.72 g (range 953-3500 g). Nearly two-thirds had ocular disorders with refractive error (51.8%), strabismus (11.3%) and a history of retinopathy of prematurity (ROP) (7.2%) being more common. One-fourth of the children had visual impairment, and the prevalence of amblyopia was 40.1%. Uncorrected refractive errors, strabismus and ROP were causes for visual impairment.

CONCLUSION

Visual impairment and amblyopia are common in Ethiopia. There is a need to develop a screening protocol for ocular disorders for preterm children to enhance early detection and prevention of childhood visual impairment.

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.

[Modern possibilities of diagnosing lesions of the visual analyzer in perinatal lesions of the central nervous system in full-term and premature infants]

The article provides an overview of current neuro-ophthalmological diagnostic capabilities in patients with perinatal lesions. The main attention is paid to the diagnosis of patients with periventricular leukomalacia and peri- and intraventricular hemorrhages. The most relevant methods of neuro-ophthalmological diagnosis in hypoxic-ischemic CNS lesions are covered. The functions and peculiarities of blood supply of the germinal matrix are described. The importance of the use of optical coherence tomography and visual evoked potential recording in full-term and premature infants with visual pathway and/or visual cortex lesions in brain lesions is discussed. The conclusion emphasizes the need for an interdisciplinary approach in the examination of children with perinatal CNS lesions.

Development of visual-motor integration scale for the Korean old people

Effective methods to detect old people cognitive decline in early stages are needed in Korea, which is the fastest aging country in the world. This study aimed to develop a brief cognitive function measurement, Visual-Motor Integration Scale for the Korean elderly (VMIS-KE). In this methodological research, 16 preliminary items on visual-motor integration for the old people were chosen after literature review and expert validation. One hundred eighty participants aged 20–79 years were recruited to verify the validity and reliability of this measurement from community sources in Daegu city. The collected data were analyzed by exploratory factor analysis and confirmative factor analysis using SPSS and AMOS 18.0 program. The three factors (figure cognition, memory, and spatial cognition) with 12 items were finally extracted. Goodness of the fit was confirmed through confirmatory factor analysis. The Cronbach α was 0.867. The scores of overall VMIS-KE and every subcategory significantly decreased with age, especially in the 70s. VMIS-KE is the first valid and reliable measurement to assess cognitive decline of the Korean old people through visual motor integration, and can easily and quickly detect high-risk groups of dementia regardless of their educational level.

Early-term deliveries and long-term pediatric ophthalmic morbidity of the offspring. Int J Gynaecol Obstet 2021;157:640-646. [PMID: 34383310 DOI: 10.1002/ijgo.13875]

OBJECTIVE

To examine whether early-term delivery impacts on the long-term ophthalmic health of offspring.

METHODS

A retrospective population-based cohort study was conducted, including all singleton deliveries (1991-2014) occurring at a tertiary medical center. Gestational age was divided into: early prematurity, late prematurity, and early, full, late, and post term. Hospitalizations of offspring up to 18 years of age involving ophthalmic morbidity were evaluated. Survival curves compared cumulative hospitalizations and regression models controlled for confounders.

RESULTS

During the study period, 243 363 deliveries met the inclusion criteria. Ophthalmic-related hospitalization rates were lower among early-term born children (1.0%) as compared with early- (2.2%) and late-preterm (1.3%) born children, but higher than those in full- (0.9%), late- (0.8%), and post-term (0.8%) born offspring (P < 0.001). The survival curve demonstrated significantly different hospitalization rates in the different gestational ages (P < 0.001). The regression demonstrated an independent risk for ophthalmic morbidity among early-term born offspring (adjusted hazard ratio 1.14, confidence interval 1.03-1.27, P = 0.009), whereas late- and post-term deliveries were associated with a lower risk (adjusted hazard ratio 0.83 and 0.74, respectively) as compared with full-term deliveries.

CONCLUSION

The risk for long-term ophthalmic-related hospitalizations of offspring gradually declines as gestational age advances.

Analysis of Brain Injury Biomarker Neurofilament Light and Neurodevelopmental Outcomes and Retinopathy of Prematurity Among Preterm Infants

IMPORTANCE

Circulating levels of neurofilament light (NfL) and glial fibrillary acidic protein (GFAP) are important in the course of brain injury in adults, but longitudinal postnatal circulating levels in preterm infants have not been investigated.

OBJECTIVES

To examine postnatal longitudinal serum levels of NfL and GFAP in preterm infants during the first 15 weeks of life and to explore possible associations between these biomarkers, neonatal morbidities, and neurodevelopmental outcomes at 2 years.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used data from 3 clinical studies, including 221 infants born before 32 weeks gestational age (GA) from 1999 to 2015; neurodevelopmental outcomes were evaluated in 120 infants. Data were collected at tertiary-level neonatal intensive care units in Gothenburg, Lund, and Uppsala, Sweden. Data analysis was conducted from January to October 2020.

EXPOSURE

Preterm birth.

MAIN OUTCOMES AND MEASURES

Serum NfL and GFAP levels, retinopathy of prematurity (ROP), intraventricular hemorrhage, and Bayley Scales of Infant Development II and III at 2 years of age, analyzed by multivariate logistic regression measured by odds ratio (OR), and receiver operating characteristic curve (ROC) analysis. Area under the curve (AUC) was also measured.

RESULTS

The 221 included infants (108 [48.9%] girls) had a mean (SD) GA at birth of 26.5 (2.1) weeks and a mean (SD) birth weight of 896 (301) grams. NfL levels increased after birth, remaining high during the first 4 weeks of life before declining to continuously low levels by postnatal age 12 weeks (median [range] NfL level at birth: 58.8 [11.5-1371.3] ng/L; 1 wk: 83.5 [14.1-952.2] ng/L; 4 wk: 24.4 [7.0-306.0] ng/L; 12 wk: 9.1 [3.7-57.0] ng/L). In a binary logistic regression model adjusted for GA at birth, birth weight SD score, Apgar status at 5 minutes, and mode of delivery, the NfL AUC at weeks 2 to 4 was independently associated with any ROP (OR, 4.79; 95% CI, 2.17-10.56; P < .001). In an exploratory analysis adjusted for GA at birth and sex, NfL AUC at weeks 2 to 4 was independently associated with unfavorable neurodevelopmental outcomes at 2 years corrected age (OR per 10-unit NfL increase, 1.07; 95% CI, 1.02-1.13; P = .01). Longitudinal GFAP levels were not significantly associated with neonatal morbidity or neurodevelopmental outcome.

CONCLUSIONS AND RELEVANCE

In this study, high NfL levels during the first weeks of life were associated with ROP and poor neurodevelopmental outcomes at 2 years of age. Associations between NfL and later neurovascular development in infants born prematurely should be investigated further.

Flash VEP in clinically stable pre-term and full-term infants

PURPOSE

Pre-term infants are at risk of abnormal visual development that can range from subtle to severe. The aim of this study was to compare flash VEPs in clinically stable pre-term and full-term infants at 6 months of age.

METHODS

Twenty-five pre-term and 25 full-term infants underwent flash VEP testing at the age of 6 months. Monocular VEPs were recorded using flash goggles on a RETIscan system under normal sleeping conditions. Amplitude and peak time responses of the P2 component in the two eyes were averaged and compared between the two groups. Multiple regression analyses were performed to assess the relationship of the P2 responses with birth weight (BW) and gestational age (GA).

RESULTS

At 6 months corrected age, pre-term infants had significantly delayed P2 peak times than full-term infants (mean difference: 10.88 [95% CI 4.00-17.76] ms, p = 0.005). Pre-term infants also showed significantly reduced P2 amplitudes as compared to full-term infants (mean difference: 2.36 [0.83-3.89] µV, p = 0.003). Although the regression model with GA and BW as fixed factors explained 20% of the variance in the P2 peak time (F_2,47 = 5.98, p = .0045), only GA showed a significant negative relationship (β = -2.66, p = .003). Neither GA (β = 0.21, p = .28) nor BW (β = 0.001, p = .32) showed any relationship with P2 amplitude.

CONCLUSIONS

Our results demonstrate that, compared with full-term infants, clinically stable pre-term infants exhibit abnormal flash VEPs, with a delay in P2 peak time and a reduction in P2 amplitude. These findings support a potential dysfunction of the visual pathway in clinically stable pre-term infants as compared to full-term infants.

Visual and Hearing Impairments After Preterm Birth

OBJECTIVES

Our aim was to determine and compare the incidences of sensory impairments among very preterm (VP) (<32 + 0/7 weeks), moderately preterm (MP) (32 + 0/7-33 + 6/7 weeks), late preterm (LP) (34 + 0/7-36 + 6/7 weeks), and term infants (≥37 weeks) and to establish risk factors of neurosensory disabilities.

METHODS

This national register study included all live-born infants in Finland between 1991 and 2008. Infants who died before the age of 1 year, who had any major congenital anomaly, or had missing data were excluded (n = 21 007; 2.0%). A total of 1 018 256 infants were analyzed. Incidences of hearing loss, visual disturbances or blindness, other ophthalmologic disorders, and retinopathy of prematurity were determined for gestational age (GA) groups. Risk factors of hearing loss and visual disturbances or blindness were analyzed.

RESULTS

The incidences of sensory impairments decreased with advancing GA at birth (P < .001). The most prominent factors associated with increased risks of hearing loss and visual impairment were intracranial hemorrhage and convulsions. VP (odds ratio [OR] 2.34; 95% confidence interval [CI] 1.75-3.14) and LP (OR 1.26; 95% CI 1.04-1.52) births were associated with an increased risk of hearing loss, and VP (OR 1.94; 95% CI 1.55-2.44), MP (OR 1.42; 95% CI 1.11-1.80), and LP (OR 1.31; 95% CI 1.16-1.49) births predicted an increased risk of visual impairment.

CONCLUSIONS

Incidences of sensory impairment decreased with increasing GA at birth. The most prominent risk factors predictive of sensory disabilities were intracranial hemorrhage and convulsions. VP and LP births were associated with an increased risk of hearing loss, and VP, MP, and LP births were associated with an increased risk of visual impairment.

Bevacizumab or laser for aggressive posterior retinopathy of prematurity

PURPOSE

The purpose of this study was to report the rate of reactivation and structural outcome, after the laser or bevacizumab treatment for aggressive posterior retinopathy of prematurity (APROP).

METHODS

Retrospective chart review was conducted on consecutive infants with APROP treated with (1) laser or (2) bevacizumab, followed by fluorescein angiography and prophylactic laser to the persistent avascular retina.

RESULTS

Thirty-six eyes of 19 patients were included in this study. The mean gestational age was 24.5 weeks with a mean birth weight of 632 g in the bevacizumab group and 24.7 weeks and 777 g in the laser group. Unfavorable outcome occurred in 1 of 22 eyes treated with bevacizumab and in 5 of 14 eyes in the laser group (P = 0.002). Reactivation requiring treatment was common in both groups, 9/22 after bevacizumab and 6/14 after laser (ns).

CONCLUSION

Regardless of the initial treatment reactivation requiring retreatment is common in eyes with APROP. The unfavorable structural outcome was significantly more common after initial laser treatment than after initial bevacizumab treatment.

Neuro-ophthalmic manifestations of prematurity

Increasing rates of preterm births coupled with better survival of these infants have resulted in higher prevalence of systemic and ocular complications associated with prematurity. In addition to retinopathy of prematurity, infants who are born preterm may suffer from severe visual impairment as a result of hypoxic ischemic encephalopathy, hypoglycemia, and other metabolic imbalances. The effect of these processes on the anterior visual pathway may result in optic atrophy, optic nerve hypoplasia or optic disc cupping and affection of the posterior visual pathway leads to cortical visual impairment (CVI). Other ocular associations include strabismus, nystagmus, and ocular motor abnormalities such as tonic down gaze and defective saccades and pursuits. Cortical and subcortical involvement also manifests as defects in functional vision and these have not yet been completely understood. Children with CVI may have visual field defects, photophobia, defective visual processing, and deficient color vision. Since most of these children also suffer from additional systemic disabilities, evaluation, and management remains a challenge. However, early diagnosis and initiation of rehabilitation therapy can prove to be of significant benefit in these children.

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.

Long-term effect of high-dose supplementation with DHA on visual function at school age in children born at <33 wk gestational age: results from a follow-up of a randomized controlled trial

BACKGROUND

Children born preterm are at risk of visual-processing impairments. Several lines of evidence have contributed to the rationale that docosahexaenoic acid (DHA) supplementation of preterm infants may improve outcomes in visual processing.

OBJECTIVE

The aim was to determine whether at 7 y of age children who were born very preterm and who received a high-DHA diet have better visual-processing outcomes than do infants fed a standard-DHA diet.

DESIGN

This was a follow-up study in a subgroup of children from a randomized controlled trial. Infants were randomly assigned to milk containing a higher concentration of DHA (1% of total fatty acids; high-DHA group) or a standard amount of DHA (0.2-0.3% of total fatty acids as DHA; control group). The randomization schedule was stratified by sex and birth weights of <1250 or ≥1250 g. A total of 104 (49 in the high-DHA group and 55 in the standard-DHA group) children aged 7 y were assessed on a range of visual-processing measures, including visual acuity, contrast sensitivity, vernier acuity, binocular stereopsis, and visual perception.

RESULTS

There was no evidence of differences between the high-DHA and standard-DHA groups in any of the visual-processing measures. In the majority (12 of 13) of variables assessed, the direction of effect favored the control group. The study was large enough to detect a moderate treatment effect, if one truly existed.

CONCLUSION

Supplementing human milk with DHA at a dose of ∼1% of total fatty acids given in the first months of life to very preterm infants does not appear to confer any long-term benefit for visual processing at school age. This trial was registered at anzctr.org/au as ACTRN12606000327583.

The contribution of visual processing to academic achievement in adolescents born extremely preterm or extremely low birth weight

Children born extremely preterm (EP, <28 weeks) and/or extremely low birth weight (ELBW, <1000 g) have more academic deficiencies than their term-born peers, which may be due to problems with visual processing. The aim of this study is to determine (1) if visual processing is related to poor academic outcomes in EP/ELBW adolescents, and (2) how much of the variance in academic achievement in EP/ELBW adolescents is explained by visual processing ability after controlling for perinatal risk factors and other known contributors to academic performance, particularly attention and working memory. A geographically determined cohort of 228 surviving EP/ELBW adolescents (mean age 17 years) was studied. The relationships between measures of visual processing (visual acuity, binocular stereopsis, eye convergence, and visual perception) and academic achievement were explored within the EP/ELBW group. Analyses were repeated controlling for perinatal and social risk, and measures of attention and working memory. It was found that visual acuity, convergence and visual perception are related to scores for academic achievement on univariable regression analyses. After controlling for potential confounds (perinatal and social risk, working memory and attention), visual acuity, convergence and visual perception remained associated with reading and math computation, but only convergence and visual perception are related to spelling. The additional variance explained by visual processing is up to 6.6% for reading, 2.7% for spelling, and 2.2% for math computation. None of the visual processing variables or visual motor integration are associated with handwriting on multivariable analysis. Working memory is generally a stronger predictor of reading, spelling, and math computation than visual processing. It was concluded that visual processing difficulties are significantly related to academic outcomes in EP/ELBW adolescents; therefore, specific attention should be paid to academic remediation strategies incorporating the management of working memory and visual processing in EP/ELBW children.

Ophthalmological findings in relation to auxological data in moderate-to-late preterm preschool children

PURPOSE

To evaluate ophthalmological findings in preschool children born moderate-to- late preterm (MLP) and relate the findings to auxological data at birth and at 5.5 years of age.

METHODS

Seventy-eight MLP children [gestational age (GA) 32-36 weeks; 34 girls; mean age 5.7 years] were investigated. Gestational age, weight, length and head circumference at birth and at the time of assessment were registered. Visual acuity (VA), refraction, orthoptic evaluation, slit-lamp examination and ophthalmoscopy were conducted, and a history of visuoperceptual problems was recorded. The data were compared with age- and sex-matched controls born full term (n = 35).

RESULTS

Ophthalmological abnormalities were noted in 82% of MLP children and 47% of controls (p = 0.0004). There was a significant difference with regard to impaired motility (p = 0.03), heterophoria at distance (p = 0.006) and refraction expressed as spherical equivalent dioptre (p = 0.01). Amongst auxological data at birth, birthweight (BW) was the strongest predictor to ophthalmological abnormalities (p = 0.0003). In a stepwise logistic regression, GA was the strongest predictor of VA outcome at time of assessment (p = 0.0036). Moderate-to-late preterm birth showed a 2.4-fold increased risk of refractive errors compared with full-term children (RR 2.39: 95% CI 1.10-5.20; p = 0.02).

CONCLUSION

Based on our findings, MLP birth may be associated with increased ocular morbidity compared with their full-term counterparts. Auxological data at birth, especially BW, seems to be an important factor when conducting an ophthalmological diagnosis in preschool MLP children, and an increased VA was correlated to a higher GA.

Retinopathy of prematurity and neurodevelopmental disabilities in premature infants

Prematurity is a major global health issue leading to high mortality and morbidity among the survivors. Neurodevelopmental disability (NDD) and retinopathy of prematurity (ROP) are the most common complications of prematurity. In fact, ROP is the second leading cause of childhood blindness in the world. Although there is much information regarding the occurrence of ROP and of NDD in premature infants, there have been few studies on ROP and its association with NDD. The objectives of this article are to review the current literature on the subject and to publish our own findings concerning the association between ROP and NDD in premature infants. The review suggests that although NDDs are related to degree of prematurity, NDD could also be the result of visual impairments resulting from ROP. Our own study shows a close association between NDD and zonal involvement of ROP: higher NDD if zone 1 is involved and less if zone 3 is involved.

A functional approach to cerebral visual impairments in very preterm/very-low-birth-weight children

BACKGROUND

Cerebral visual impairment (CVI) is a major cause of visual impairment, with very preterm birth/very low birth weight (VP/VLBW) being a major risk factor. There is no generally accepted definition of CVI. This study aims to investigate the usefulness of an empirically-based functional definition of CVI.

METHODS

One-hundred-five VP/VLBW children and 67 controls participated. CVI was defined after comprehensive oculomotor, visual sensory and perceptive assessment, and validated against vision problems in daily life and in terms of intellectual, behavioral, emotional and social functioning, as well as use of therapeutic services.

RESULTS

Twenty-four per cent of the VP/VLBW children met criteria for CVI, compared to 7% of controls (P = 0.006, OR: 3.86, 95% CI: 1.40-10.70). VP/VLBW children with CVI had lower performance IQ, but not verbal IQ, than those without CVI. Visual problems in daily life were confirmed in VP/VLBW children classified with CVI. Additionally, difficulties in behavioral and social functioning were most prominent among VP/VLBW children with CVI.

CONCLUSION

In VP/VLBW children, CVI defined in terms of visual function deficits is accompanied by intellectual, behavioral, and social impairments, validating our operational definition of CVI. CVI might act as a marker for developmental problems in VP/VLBW children.

Visual Development and Neuropsychological Profile in Preterm Children from 6 Months to School Age

The aim of this semilongitudinal study was to investigate the development of central visual pathways in children born preterm but without major neurologic impairments and to establish their cognitive and behavioral profile at school age. Ten children born preterm were assessed at 6 months and at school age, using visual evoked potentials at both time points and cognitive and behavioral tests at school age. We also tested 10 age-matched children born full-term. At 6 months' corrected age, we found no significant differences between preterm and full-term groups for either amplitude or latency of N1 and P1 components. At school age, the preterm group manifested significantly higher N1 amplitudes and tended to show higher P1 amplitudes than the full-term group. We found no significant differences in cognitive and behavioral measures at school age. These results suggest that preterm birth affects visual pathways development, yet the children born preterm did not manifest cognitive problems.

Visual sensory and perceptive functioning in 5-year-old very preterm/very-low-birthweight children

AIM

To examine visual sensory and perceptive functions, study their interrelations, and explore associations between visual dysfunctions and intelligence in very preterm/very-low-birthweight (VP/VLBW) children.

METHOD

One-hundred and sixteen VP/VLBW children (57 males, 59 females; mean gestational age 30.1 wks, SD 2.3; mean corrected age 5 y 6 mo, SD 1 mo) and 73 term-born children (40 males, 33 females; mean gestational age 39.9 wks, SD 1.3; mean age 5 y 6 mo, SD 3 mo) completed visual sensory (acuity, visual field, contrast-, color-, and stereovision), perceptive (visual coherence, and Developmental Test of Visual Perception non-motor scale), and intelligence assessments.

RESULTS

Compared with term-born children, VP/VLBW children had reduced acuity (d=0.70, p<0.001), inferior visual field (d=0.67, p<0.001), and stereovision (v=0.19, p=0.008). VP/VBLW children showed weaker static coherence (d=0.49, p=0.001) and Position in Space (d=0.41, p=0.006) performance, independent of visual sensory deficits, and showed lower Verbal IQ (VIQ) and Performance IQ (PIQ; p<0.001). Visual perceptive functioning accounted for 13% of variance in VIQ, and for 35% of variance in PIQ.

INTERPRETATION

Visual sensory and perceptive dysfunctions are present in VP/VLBW children and occur largely independently of each other. Visual perceptive dysfunctions are moderately associated with PIQ, and weakly with VIQ.

Local and global aspects of biological motion perception in children born at very low birth weight

Biological motion perception can be assessed using a variety of tasks. In the present study, 8- to 11-year-old children born prematurely at very low birth weight (<1500 g) and matched, full-term controls completed tasks that required the extraction of local motion cues, the ability to perceptually group these cues to extract information about body structure, and the ability to carry out higher order processes required for action recognition and person identification. Preterm children exhibited difficulties in all 4 aspects of biological motion perception. However, intercorrelations between test scores were weak in both full-term and preterm children--a finding that supports the view that these processes are relatively independent. Preterm children also displayed more autistic-like traits than full-term peers. In preterm (but not full-term) children, these traits were negatively correlated with performance in the task requiring structure-from-motion processing, r(30) = -.36, p < .05), but positively correlated with the ability to extract identity, r(30) = .45, p < .05). These findings extend previous reports of vulnerability in systems involved in processing dynamic cues in preterm children and suggest that a core deficit in social perception/cognition may contribute to the development of the social and behavioral difficulties even in members of this population who are functioning within the normal range intellectually. The results could inform the development of screening, diagnostic, and intervention tools.

Ocular alignment and refraction in preterm children at 1 and 6 years old

Purpose

To investigate cycloplegic refraction and ocular alignment in a population of preterm children at 1 and 6 years old.

Patients and methods

We included 261 preterm infants with a birth weight ≤1,500 g and a gestational age ≤32 weeks; there were 217 preterm infants (group 1), 28 preterm infants with mild retinopathy of prematurity (ROP) (group 2), and 16 preterm infants affected by severe ROP (group 3). Each patient underwent retinoscopy, ocular alignment assessment, and fundus examination at 1 and 6 years old.

Results

The prevalence of refractive errors and ocular alignment abnormalities at 1 year old in groups 2 and 3 compared to group 1 were, respectively (P<0.05): myopia 18% and 40.6% versus 6.9%; hyperopia 28.6% and 22% versus 39.2%; astigmatism 53.4% and 37.4% versus 53.9%; and strabismus 12.5% and 38% versus 5.3%. At 6 years old, they were, respectively (P<0.05): myopia 10.8% and 28.4% versus 7.4%; hyperopia 48.3% and 40.5% versus 62%; astigmatism 40.9% and 31.1% versus 30.6%; and strabismus 25% and 56.25% versus 11.5%.

Conclusion

At 6 years old, we observed increased rates of both hyperopia and strabismus in all groups compared to 1-year-old children. In preterm children with mild and severe ROP, we recorded increased rates of myopia and strabismus versus preterm children without ROP, and the risk of developing these disorders increased significantly with ROP severity. Astigmatism at 1 year old is not predictive of further development during growth. Patients born prematurely should be informed of the possible risks of ocular alterations due to refractive and ocular component changes.

Retinopathy of prematurity and brain damage in the very preterm newborn

PURPOSE

To explain why very preterm newborns who develop retinopathy of prematurity (ROP) appear to be at increased risk of abnormalities of both brain structure and function.

METHODS

A total of 1,085 children born at <28 weeks' gestation had clinically indicated retinal examinations and had a developmental assessment at 2 years corrected age. Relationships between ROP categories and brain abnormalities were explored using logistic regression models with adjustment for potential confounders.

RESULTS

The 173 children who had severe ROP, defined as prethreshold ROP (n = 146) or worse (n = 27) were somewhat more likely than their peers without ROP to have brain ultrasound lesions or cerebral palsy. They were approximately twice as likely to have very low Bayley Scales scores. After adjusting for risk factors common to both ROP and brain disorders, infants who developed severe ROP were at increased risk of low Bayley Scales only. Among children with prethreshold ROP, exposure to anesthesia was not associated with low Bayley Scales.

CONCLUSIONS

Some but not all of the association of ROP with brain disorders can be explained by common risk factors. Most of the increased risks of very low Bayley Scales associated with ROP are probably not a consequence of exposure to anesthetic agents.

Alterations in the optic radiations of very preterm children-Perinatal predictors and relationships with visual outcomes

Children born very preterm (VPT) are at risk for visual impairments, the main risk factors being retinopathy of prematurity and cerebral white matter injury, however these only partially account for visual impairments in VPT children. This study aimed to compare optic radiation microstructure and volume between VPT and term-born children, and to investigate associations between 1) perinatal variables and optic radiations; 2) optic radiations and visual function in VPT children. We hypothesized that optic radiation microstructure would be altered in VPT children, predicted by neonatal cerebral white matter abnormality and retinopathy of prematurity, and associated with visual impairments.

142 VPT children and 32 controls underwent diffusion-weighted magnetic resonance imaging at 7 years of age. Optic radiations were delineated using constrained spherical deconvolution tractography. Tract volume and average diffusion tensor values for the whole optic radiations and three sub-regions were compared between the VPT and control groups, and correlated with perinatal variables and 7-year visual outcome data.

Total tract volumes and average diffusion values were similar between VPT and control groups. On regional analysis of the optic radiation, mean and radial diffusivity were higher within the middle sub-regions in VPT compared with control children. Neonatal white matter abnormalities and retinopathy of prematurity were associated with optic radiation diffusion values. Lower fractional anisotropy in the anterior sub-regions was associated with poor visual acuity and increased likelihood of other visual defects.

This study presents evidence for microstructural alterations in the optic radiations of VPT children, which are largely predicted by white matter abnormality or severe retinopathy of prematurity, and may partially explain the higher rate of visual impairments in VPT children.

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This study compares optic radiations between very preterm and control 7-year-olds.

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There are microstructural alterations in the optic radiations of VPT children.

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The main risk factors are retinopathy of prematurity and white matter injury.

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Microstructural alterations associate with poor visual acuity and visual defects.

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This study elucidates neuroanatomical correlates of visual impairment in prematurity.

Visual, motor, and psychomotor development in small-for-gestational-age preterm infants

PURPOSE

To study causal links between the visual, cognitive, and psychomotor outcomes of premature babies who are small for gestational age (SGA).

METHODS

A cohort study of 17 SGA cases and 34 controls who were appropriate for gestational age (AGA) was carried out. The cases were all premature babies without any other pathology. All subjects underwent a visual, mental, and psychomotor evaluation at 1 year of age.

RESULTS

Of the SGA cases, 41% had a "below normal" visual acuity versus 17.7% of the AGA controls. At 1 year of age the SGA babies showed an odds ratio of 18.73 for low visual acuity, 9.09 for low mental performance, and no significant risk for a decreased psychomotor performance.

CONCLUSIONS

In this small cohort of premature infants, the SGA babies were more prone to developing low visual performance and abnormal cognitive development.

Delayed luminance and chromatic contrast sensitivity in infants with spontaneously regressed retinopathy of prematurity

BACKGROUND

The current study assessed whether contrast sensitivity is affected in preterm infants with a history of spontaneously regressed retinopathy of prematurity (ROP, Stages 1-3). Specifically, we employed luminance (light/dark) and chromatic (red/green) stimuli, which are mediated by the magnocellular (M) and parvocellular (P) subcortical pathways, respectively.

METHODS

Contrast sensitivity (CS) was measured using forced-choice preferential looking testing in 21 infants with a history of ROP and 41 control preterm infants who were born prematurely but did not develop ROP, tested between 8 and 47 weeks (2-11 months) postterm age. Infants were presented with chromatic and luminance drifting sinusoidal gratings, which appeared randomly on the left or right side of the monitor in each trial. The contrast of the stimuli varied across trials and was defined in terms of root mean squared cone contrast for long- and medium-wavelength cones.

RESULTS

Between 8 and 25 weeks postterm, ROP infants had significantly worse CS, and there was a trend for greater impairment for luminance than chromatic CS. This delay was not seen at older ages between 26 and 47 weeks postterm.

CONCLUSIONS

These findings are consistent with the concept that early maturation of the M pathway is vulnerable to biological insult, as in the case of ROP, to a greater extent than in the P pathway.

Clinical characteristics of children with severe visual impairment but favorable retinal structural outcomes from the Early Treatment for Retinopathy of Prematurity (ETROP) study

PURPOSE

To describe visual function and associated characteristics at the 6-year examination in children enrolled in the Early Treatment for Retinopathy of Prematurity Study who had unfavorable visual outcomes despite favorable structural outcomes in one or both eyes.

METHODS

The clinical examination records of children completing the 6-year follow-up examination were retrospectively reviewed. Eligible subjects were those with visual acuity of ≤20/200 in each eye (where recordable) and a normal fundus or straightening of the temporal retinal vessels with or without macular ectopia in at least one eye. Data regarding visual function, retinal structure, presence of nystagmus, optic atrophy, optic disk cupping, seizures/shunts, and Functional Independence Measure for Children (ie, WeeFIM: pediatric functional independence measure) developmental test scores were reviewed.

RESULTS

Of 342 participants who completed the 6-year examination, 39 (11%) met inclusion criteria. Of these, 29 (74%) had normal retinal structure, 18 (46%) had optic atrophy, and 3 (8%) had increased cupping of the optic disk in at least one eye. Latent and/or manifest nystagmus occurred in 30 children (77%). The presence of nystagmus was not related to the presence of optic atrophy. Of the 39 children, 28 (72%) had a below-normal WeeFIM score.

CONCLUSIONS

In 25 participants (7%) completing the 6-year examination, cortical visual impairment was considered the primary cause of visual loss. The remainder likely had components of both anterior and posterior visual pathway disease. Clinical synthesis of ocular anatomy and visual and neurologic function is required to determine the etiology of poor vision in these children.

Flash visual evoked potentials in preterm infants

OBJECTIVE

To describe the development of flash visual evoked potentials (FVEPs) in preterm infants from 1 to 18 months and to determine if the maturation of FVEPs is similar to that of term infants.

DESIGN

Longitudinal follow-up study.

PARTICIPANTS

Twenty very low birth weight (VLBW) preterm infants, 42 low birth weight (LBW) preterm infants, and 41 term infants underwent FVEP recordings and neurodevelopmental examinations at 1, 3, 6, 9, 12, and 18 months of corrected and chronological ages.

METHODS

The FVEP recordings were carried out with the VikingQuest-IV neuroelectrophysiological device (VikingQuest, Nicolet, WI), and neurodevelopmental assessments were made by the Development Screen Test and Bayley Scales of Infant Development, Second Edition.

MAIN OUTCOME MEASURES

At 1, 3, 6, and 9 months of age, neurodevelopment was measured with the Mental Index and Developmental Quotient. At 12 and 18 months, neurodevelopment was assessed using the Mental Developmental Index and Psychomotor Developmental Index. Two FVEP values were analyzed: the P2 amplitude (peak to peak from the preceding N2 wave) and the latency of the P2 wave.

RESULTS

There was no significant difference for age-dependent decreased pattern of FVEP P2 latency between preterm infants and the control group. This pattern consisted of a rapid decrease in the first 6 months of life, a gradual decline from 6 to 12 months of age, and a steady reduction from 12 to 18 months of age. The P2 latencies were prolonged significantly at all 6 recorded times in the VLBW group compared with the controls and showed a delay in the LBW group at 1 and 3 months of corrected age. The maturation of P2 latency in LBW infants is similar to that of the controls at 3 months of corrected age, but the maturation of P2 latency in VLBW children remained delayed when compared with the controls until 18 months of corrected age.

CONCLUSIONS

Although the FVEP development pattern of preterm infants was similar to that of healthy full-term infants, the former had deficits in visual electrophysiologic maturation, especially for VLBW children.

Visual function in 6 to 7 year-old children born extremely preterm: a population-based study

PURPOSE

Progress in neonatal care has caused an increased survival of children born extremely preterm. The aims of this study were to examine the long-term visual function and ocular development in an unselected cohort of extremely preterm infants and relate the results to neonatal morbidity and long-term neurodevelopmental outcome.

METHODS

All children with gestational age of 22-27 completed weeks or birth weight of 500-999 g born in the years 1999-2000 in two counties of Western Norway (n = 52) were invited to an eye examination that included visual acuity, refractive error, binocular function, accommodative amplitude and fundus examination. Cognitive function was assessed with the WPSSI-R test and motor abilities with the ABC movement test.

RESULTS

Neonatal morbidities and neurodevelopmental outcome were known for all, while 37 of the 52 children underwent the eye examination. None were blind or visually impaired, but 46% had subnormal visual acuity (logMAR ≥0.1). Ninety per cent were emmetropic or slightly hypermetropic (0 to +3D), while 10% had manifest and 51% latent strabismus. Performance IQ on the WPSSI-R test and ABC total score were associated with best visual acuity (p = 0.03 and p < 0.01, respectively). In a multiple linear regression model, visual acuity in the best eye was significantly associated with performance IQ (p = 0.03) and ABC total score (p = 0.02).

CONCLUSION

This study suggests a more favourable long-term prognosis on important ocular and visual parameters in survivors of extreme prematurity than expected from similar reports on children born less prematurely and that performance IQ and motor function are related to visual acuity.

Visual function and white matter microstructure in very-low-birth-weight (VLBW) adolescents--a DTI study

Premature birth is associated with visual impairments, due to both cerebral and ocular pathology. This study examined the relationship between cerebral white matter microstructure, evaluated by diffusion tensor imaging (DTI), and visual function, in 30 preterm born adolescents with very low birth weight (VLBW=birth weight⩽1500g) and an age-matched group of 45 term born controls. Visual acuity correlated positively with fractional anisotropy (FA) in corpus callosum and in frontal white matter areas in the VLBW participants, but not in the control participants. Callosal visual connections may play a more important role in the development of good visual acuity than previously acknowledged in preterm born children.

Visual perception in preterm children: what are we currently measuring?

Over the past two decades, cerebral visual impairment has been recognized as a principal deficit in preterm children, and in particular those with cerebral palsy. We review the current knowledge of visual processing deficits in these children, and provide an overview of the tools for assessing cerebral visual impairment. Commercially available instruments are usually directed at evaluating visuospatial skills rather than detecting object recognition difficulties. Particularly in children aged 3 years or younger and in children with multiple handicaps, cerebral visual impairment is difficult to diagnose. This difficulty may be attributable to limitations specific to the instrument, such as a test that is inappropriate for age, or to child-specific limitations such as motor impairment or speech delay. We therefore include an overview of relevant neuroimaging findings reported in these children, focusing on the most recent imaging modalities. Novel techniques such as diffusion tensor imaging may provide sensitive markers of cerebral visual impairment in situations where clinical diagnosis is difficult, and such approaches may allow for early intervention.

Visual perceptual difficulties and under-achievement at school in a large community-based sample of children

Introduction

Difficulties with visual perception (VP) are often described in children with neurological or developmental problems. However, there are few data regarding the range of visual perceptual abilities in populations of normal children, or on the impact of these abilities on children's day-to-day functioning.

Methods

Data were obtained for 4512 participants in an ongoing birth cohort study (Avon Longitudinal Study of Parents and Children; ALSPAC). The children's mothers responded to questions designed to elicit indications of visual perceptual difficulties or immaturity, when their children were aged 13 years. We examined associations with standardised school test results in reading and in mathematics at age 13–14 years (SATS-KS3), accounting for potential confounders including IQ.

Results

Three underlying factors explained half the variance in the VP question responses. These correlated best with questions on interpreting cluttered scenes; guidance of movement and face recognition. The adjusted parameter estimates (95% CI) for the cluttered-scenes factor (0.05; 0.02 to 0.08; p<0.001) suggested positive associations with the reading test results whilst that for the guidance-of-movement factor (0.03; 0.00 to 0.06; p = 0.026) suggested positive association with the mathematics results. The raw scores were associated with both test results.

Discussion

VP abilities were widely distributed in this sample of 13-year old children. Lower levels of VP function were associated with under-achievement in reading and in mathematics. Simple interventions can help children with VP difficulties, so research is needed into practicable, cost-effective strategies for identification and assessment, so that support can be targeted appropriately.

Prediction of neurodevelopmental and sensory outcome at 5 years in Norwegian children born extremely preterm

OBJECTIVE

To examine the prevalence of neurodevelopmental disability and the predictive value of pre-, peri-, and postnatal data on neurologic, sensory, cognitive, and motor function in children born extremely preterm.

METHODS

This was a prospective observational study of all infants born in Norway between 1999 and 2000 with gestational ages between 22 and 27 weeks or birth weights between 500 and 999 g. Cognitive function was assessed with the Wechsler Preschool and Primary Scale of Intelligence-Revised, motor function with the Movement Assessment Battery for Children, and severity of cerebral palsy with the Gross Motor Function Classification for Cerebral Palsy. Disabilities were described as mild, moderate, or severe.

RESULTS

Of 371 eligible children, 306 (82%) were examined at a mean (SD) age of 5 years and 10 (4) months. For gestational age less than 28 weeks (n = 239), 26 (11%) children had cerebral palsy alone (n = 21) or in combination with blindness (n = 3) or deafness (n = 2); 1 was blind and 1 was deaf. Of the remaining children, the mean full-scale IQ was 94 ± 15, and significant predictors were (values given as the difference in IQ points [95% confidence intervals]) high maternal education (9.6 [5.7-13.4]), preeclampsia (-7.7 [-12.7 to -2.7]), and retinopathy of prematurity higher than grade 2 (-17.5 [-27.1 to -8.0]). Movement Assessment Battery for Children scores were positively associated with gestational age and prenatal steroids and negatively associated with being small for gestational age, male gender, and having retinopathy of prematurity. Moderate to severe neurodevelopmental disability was more common for gestational ages 25 weeks or less (28 of 87 children) than for 26 to 27 weeks (12 of 152 children; P < .001) and 28 weeks or more (7 of 67 children; P = .001).

CONCLUSIONS

The outcome was poorer for children with gestational ages of 25 weeks or less compared with those with gestational ages between 26 and 27 weeks. For those without cerebral palsy, blindness, or deafness, however, gestational age had a limited association with cognitive and motor function.

Health and the use of health care services in 5-year-old very-low-birth-weight infants

AIM

We aimed to study the effect of prematurity, time of birth and level of birth hospital on morbidity and the use of health care services at age 5.

METHODS

This national study included all very-low-birth-weight infants (VLBWI, <32 gestational weeks or birth weight < or =1500 g) born in Finnish level II or III hospitals in 2001-2002 (n = 918), and full-term controls (n = 381). Parental questionnaires and register data were used to compare morbidity, and the use of health care services between VLBWI and full-term controls, and within VLBWI according to the time of birth and birth hospital level.

RESULTS

Cerebral palsy, retinopathy of prematurity, other ophthalmic problems, respiratory infections, asthma or chronic lung disease, and inguinal hernia were overrepresented in VLBWI compared with the controls. VLBWI had more outpatient and inpatient days than the controls. The time of birth and birth hospital level were not associated with the use of services or with prematurity-related morbidity.

CONCLUSION

Although morbidity and the use of health care services were increased in the surviving VLBWI, the average use of services was relatively small at age 5. In surviving VLBWI, the time of birth and the birth hospital level did not affect morbidity or the use of services.

Flash visual evoked potentials at 2-year-old infants with different birth weights

BACKGROUND

Increased prevalence of visual impairments has been reported in preterm populations. However, it remains unclear about the long-term visual electrophysiological outcomes and their association with visual cognitive functions in premature infants. We investigated visual electrophysiological outcome of 2-year-old infants of different birth weights by flash visual evoked potentials (FVEPs) in order to explore the correlation between visual cognitive functions and FVEPs and to assess the application of FVEPs in evaluating the visual capability of an infant.

METHODS

The FVEPs of 77 infants, including 25 very low birth weight (VLBW) premature infants, 16 low birth weight (LBW) premature infants and 36 full-term infants, were tested with a visual electrophysiological testing device. Neuromotor development was assessed with the Bayley Scales of Infant Development, Second Edition (BSID-II). The visual cognitive functions were evaluated by scoring the proportion passed of 12 items chosen from the BSID-II for infants at 23 to 25 months of age.

RESULTS

The second prominent positive wave (P2) was the major component presented in all three groups. The mean latency of P2 in the VLBW, LBW and full-term groups was 149.65+/-23.79 ms, 129.39+/-8.70 ms, and 126.14+/-7.73 ms respectively. There was no significant difference in mean latency of P2 wave between the LBW and full-term groups; the mean latency of the P2 wave in the VLBW group was delayed more significantly than those of the other two groups. The difference in amplitude of the P2 peak to the preceding N2 peak (N2P2) between the three groups was not statistically significant. The latency of the P2 main wave was negatively correlated with mental developmental index (MDI) (r'(MDI) = -0.35) and visual cognitive capability (r'(visual capability) = -0.21).

CONCLUSIONS

The latency of the P2 main wave on FVEPs was delayed more significantly in premature infants than in full-term infants at 2 years of corrected age. The visual functional development was delayed in premature infants, especially in VLBW infants (gestational age <32 weeks). The FVEPs were reported low but there were statistically significant correlations between measures of visual cognition and P2 peak latency. As a noninvasive and convenient method, FVEPs are useful in assessing certain aspects of an infant's visual development and visual function.

Responses to a modified visual cliff by pre-walking infants born preterm and at term

The purpose of this study was to examine, using a modified visual cliff apparatus, possible perceptual differences at crawling age between infants born preterm and infants born at term without documented visual or motor impairments. Sixteen infants born at term and 16 born preterm were encouraged to crawl to their caregivers on a modified visual cliff. Successful trials, crossing time, duration of visual attention, duration of tactile exploration, motor strategies, and avoidance behaviors were analyzed. A significant surface effect was found, with longer crossing times and longer durations of visual attention and tactile exploration in the condition with the visual appearance of a deep cliff. Although the two groups of infants did not differ on any of the timed measures, infants born at term demonstrated a larger number of motor strategies and avoidance behaviors by simple tally. This study indicates that infants born at term and those born preterm can perceive a visual cliff and adapt their responses accordingly.

Immaturity, perinatal inflammation, and retinopathy of prematurity: a multi-hit hypothesis

OBJECTIVE

To explore the relationship among markers of infection/inflammation in their association with retinopathy of prematurity (ROP).

METHODS

We studied clinical characteristics and 4 single nucleotide polymorphisms in infection/inflammation-associated genes in a group of 73 children with a gestational age<32 weeks. Forty-four children (60%) had ROP, of whom 13 (30% of those with ROP) progressed to stage 3 ROP. No child had grade 4 or 5 ROP. We employed both descriptive and analytic statistical methods.

RESULTS

Clinical variables of infection/inflammation were consistently associated with an increased risk of ROP. Among infants with ROP, they were also associated with progression to ROP grade 3. Genetic markers were not associated with ROP occurrence, but with progression to high grade disease. In tri-variable analyses exploring the effects of gestational age <29 weeks, clinical chorioamnionitis (CAM) and neonatal systemic inflammatory response syndrome (SIRS) on ROP occurrence, low gestational age was the most important antecedent, while additional individual or joint exposure to SIRS and CAM add appreciably to this risk of progression to high grade disease.

CONCLUSION

Both antenatal and neonatal exposure to inflammation appear to contribute to the increased ROP risk in preterm infants.

Do visual impairments affect risk of motor problems in preterm and term low birth weight adolescents?

BACKGROUND

Increased prevalence of motor and visual problems has been reported in low birth weight populations, but the association between them is less studied.

AIM

To examine how visual impairments may be associated with the increased risk of motor problems in low birth weight adolescents.

METHODS

Fifty-one very low birth weight adolescents (VLBW), 56 term small for gestational age (SGA) and 75 term control adolescents, without cerebral palsy, were examined at the age of 14. Motor skills were examined by the Movement Assessment Battery for Children. Visual functions included visual acuity, contrast sensitivity, nystagmus, strabismus, stereoacuity, accommodation, convergence and visual perception (Visual-Motor Integration test). An abnormality score was calculated as the sum of visual impairments. We used odds ratio as an estimate of the relative risk of having motor problems.

RESULTS

The odds of having motor problems were 10.4 (95% CI: 2.2-49.4) in the VLBW group and 5.1 (95% CI: 1.0-25.8) in the SGA group compared with the control group. The odds of having motor problems in the VLBW group were influenced by all visual variables, and most by visual acuity, when we adjusted for these separately. The greatest reduction in OR was found when adjusting for the abnormality score (adjusted OR: 6.8; 95% CI: 1.3-34.5). In the SGA group the odds of having motor problems were relatively unaffected by the visual variables and the abnormality score.

CONCLUSIONS

Visual impairments influence motor problems in VLBW adolescents, whereas motor problems in SGA adolescents seem to be unaffected by visual impairments.