Early brain injury in premature newborns detected with magnetic resonance imaging is associated with adverse early neurodevelopmental outcome

Location and Size of Preterm Cerebellar Hemorrhage and Childhood Development

OBJECTIVE

To examine the association between cerebellar hemorrhage (CBH) size and location and preschool-age neurodevelopment in very preterm neonates.

METHODS

Preterm magnetic resonance images of 221 very preterm neonates (median gestational age = 27.9 weeks) were manually segmented for CBH quantification and location. Neurodevelopmental assessments at chronological age 4.5 years included motor (Movement Assessment Battery for Children, 2nd Edition [MABC-2]), visuomotor integration (Beery-Buktenica Developmental Test of Visual-Motor Integration, 6th Edition), cognitive (Wechsler Primary and Preschool Scale of Intelligence, 3rd Edition), and behavioral (Child Behavior Checklist) outcomes. Multivariable linear regression models examined the association between CBH size and 4.5-year outcomes accounting for sex, gestational age, and supratentorial injury. Probabilistic maps assessed CBH location and likelihood of a lesion to predict adverse outcome.

RESULTS

Thirty-six neonates had CBH: 14 (6%) with only punctate CBH and 22 (10%) with ≥1 larger CBH. CBH occurred mostly in the inferior aspect of the posterior lobes. CBH total volume was independently associated with MABC-2 motor scores at 4.5 years (β = -0.095, 95% confidence interval = -0.184 to -0.005), with a standardized β coefficient (-0.16) that was similar to that of white matter injury volume (standardized β = -0.22). CBH size was similarly associated with visuomotor integration and externalizing behavior but not cognition. Voxelwise odds ratio and lesion-symptom maps demonstrated that CBH extending more deeply into the cerebellum predicted adverse motor, visuomotor, and behavioral outcomes.

INTERPRETATION

CBH size and location on preterm magnetic resonance imaging were associated with reduced preschool motor and visuomotor function and more externalizing behavior independent of supratentorial brain injury in a dose-dependent fashion. The volumetric quantification and localization of CBH, even when punctate, may allow opportunity to improve motor and behavioral outcomes by providing targeted intervention. ANN NEUROL 2020;88:1095-1108.

Application of voxel-based morphometric method to detect brain changes in children with non-cyanotic congenital heart disease

BACKGROUND

Congenital heart disease (CHD) is a cardiovascular malformation caused by abnormal heart and/or vascular development in the fetus. In children with CHD, abnormalities in the development and function of the nervous system are common. At present, there is a lack of research on the preoperative neurological development and injury in young children with non-cyanotic CHD.

AIM

To determine the changes in white matter, gray matter, and cerebrospinal fluid (CSF) by magnetic resonance imaging (MRI) in children with non-cyanotic CHD as compared with healthy controls.

METHODS

Children diagnosed with non-cyanotic CHD on ultrasonography (n = 54) and healthy control subjects (n = 35) were included in the study. All the subjects were aged 1-3 years. Brain MRI was performed prior to surgery for CHD. The SPM v12 software was used to calculate the volumes of the gray matter, white matter, CSF, and the whole brain (sum of the gray matter, white matter, and CSF volumes). Volume differences between the two groups were analyzed. Voxel-based morphometry was used to compare specific brain regions with statistically significant atrophy.

RESULTS

Compared with the control group, the study group had significantly reduced whole-brain white matter volume (P < 0.05), but similar whole-brain gray matter, CSF, and whole-brain volumes (P > 0.05). As compared with the healthy controls, children with non-cyanotic CHD had mild underdevelopment in the white matter of the anterior central gyrus, the posterior central gyrus, and the pulvinar.

CONCLUSION

Children with non-cyanotic CHD show decreased white matter volume before surgery, and this volume reduction is mainly concentrated in the somatosensory and somatic motor nerve regions.

Feed-forward neural networks using cerebral MR spectroscopy and DTI might predict neurodevelopmental outcome in preterm neonates

Objectives

We aimed to evaluate the ability of feed-forward neural networks (fNNs) to predict the neurodevelopmental outcome (NDO) of very preterm neonates (VPIs) at 12 months corrected age by using biomarkers of cerebral MR proton spectroscopy (¹H-MRS) and diffusion tensor imaging (DTI) at term-equivalent age (TEA).

Methods

In this prospective study, 300 VPIs born before 32 gestational weeks received an MRI scan at TEA between September 2013 and December 2017. Due to missing or poor-quality spectroscopy data and missing neurodevelopmental tests, 173 VPIs were excluded. Data sets consisting of 103 and 115 VPIs were considered for prediction of motor and cognitive developmental delay, respectively. Five metabolite ratios and two DTI characteristics in six different areas of the brain were evaluated. A feature selection algorithm was developed for receiving a subset of characteristics prevalent for the VPIs with a developmental delay. Finally, the predictors were constructed employing multiple fNNs and fourfold cross-validation.

Results

By employing the constructed fNN predictors, we were able to predict cognitive delays of VPIs with 85.7% sensitivity, 100% specificity, 100% positive predictive value (PPV) and 99.1% negative predictive value (NPV). For the prediction of motor delay, we achieved a sensitivity of 76.9%, a specificity of 98.9%, a PPV of 90.9% and an NPV of 96.7%.

Conclusion

FNNs might be able to predict motor and cognitive development of VPIs at 12 months corrected age when employing biomarkers of cerebral ¹H-MRS and DTI quantified at TEA.

Key Points

• A feed-forward neuronal network is a promising tool for outcome prediction in premature infants.

• Cerebral proton magnetic resonance spectroscopy and diffusion tensor imaging can be used for the construction of early prognostic biomarkers.

• Premature infants that would most benefit from early intervention services can be spotted at the time of optimal neuroplasticity.

Electronic supplementary material

The online version of this article (10.1007/s00330-020-07053-8) contains supplementary material, which is available to authorized users.

Disruption and Compensation of Sulcation-based Covariance Networks in Neonatal Brain Growth after Perinatal Injury

Perinatal brain injuries in preterm neonates are associated with alterations in structural neurodevelopment, leading to impaired cognition, motor coordination, and behavior. However, it remains unknown how such injuries affect postnatal cortical folding and structural covariance networks, which indicate functional parcellation and reciprocal brain connectivity. Studying 229 magnetic resonance scans from 158 preterm neonates (n = 158, mean age = 28.2), we found that severe injuries including intraventricular hemorrhage, periventricular leukomalacia, and ventriculomegaly lead to significantly reduced cortical folding and increased covariance (hyper-covariance) in only the early (<31 weeks) but not middle (31-35 weeks) or late stage (>35 weeks) of the third trimester. The aberrant hyper-covariance may drive acceleration of cortical folding as a compensatory mechanism to "catch-up" with normal development. By 40 weeks, preterm neonates with/without severe brain injuries exhibited no difference in cortical folding and covariance compared with healthy term neonates. However, graph theory-based analysis showed that even after recovery, severely injured brains exhibit a more segregated, less integrated, and overall inefficient network system with reduced integration strength in the dorsal attention, frontoparietal, limbic, and visual network systems. Ultimately, severe perinatal injuries cause network-level deviations that persist until the late stage of the third trimester and may contribute to neurofunctional impairment.

Neurocognitive impairment after neonatal sepsis: protocol for a systematic review and meta-analysis

INTRODUCTION

The effect of neonatal sepsis on the developing brain is not well documented. We aim to perform evidence synthesis to determine the outcome of neurodevelopmental impairment and intellectual disability among survivors of neonatal sepsis. The data gathered will inform on the long-term neurocognitive outcomes of neonates with sepsis and the measures used to document their developmental disability.

METHODS AND ANALYSIS

We will perform a search based on the following parameters: neonates and infants less than 90 days old diagnosed with sepsis who had neurocognitive outcomes or measures of developmental disability reported. We will search PubMed, Cochrane Central, Embase and Web of Science for articles in English language published between January 2010 and December 2019. Clinical trials and observational studies will be included. Two independent reviewers will screen studies for eligibility. Data extraction will then be performed using a standardised form. The quality of evidence and risk of bias will be assessed using Cochrane Collaboration's tool and Risk of Bias in Non-randomised Studies of Intervention (ROBINS-I). The results will be synthesised qualitatively and pooled for meta-analysis.

ETHICS AND DISSEMINATION

No formal ethical approval is required as there is no collection of primary data. This systematic review and meta-analysis will be disseminated through conference meetings and peer-reviewed publications.

PROSPERO REGISTRATION NUMBER

Registration submitted CRD42020164334.

Developmental outcomes of very low birthweight infants with non-hemorrhagic ventricular dilatations and the relationships thereof with absolute brain volumes measured via two-dimensional ultrasonography

PURPOSE

We calculated the brain volumes of preterm infants using two-dimensional cranial ultrasonography and explored the relationships thereof with neurodevelopment.

METHODS

Cranial measurements were derived using routine ultrasonographic scanning. The brain was considered to be an ellipsoid and estimated absolute brain volumes (EABVs) were calculated by substracting the volumes of the two lateral ventricles from the total brain volumes.

RESULTS

We enrolled preterm infants of mean gestational age 28 ± 2 weeks and mean birthweight 973 ± 187 g. Twenty-one exhibited dilated ventricles; their EABVs were lower than normal (206 ± 11 cm³ vs. 275 ± 17 cm³, p < 0.001). The mental development indices were similar (74 ± 5 vs. 78 ± 14, p = 0.069), but the psychomotor development indices (PDIs) differed significantly (77 ± 7 vs. 86 ± 17, p = 0.001). We found a slight positive correlation between the PDI and EABV (r = + 0.258, p = 0.012).

CONCLUSION

The EABV can be calculated using two-dimensional measurements and low EABV found to be associated with poor neurological outcomes.

TRIAL REGISTRATION

NCT02848755.

Cerebral palsy after very preterm birth - an imaging perspective

Neonatal brain imaging undoubtedly can provide the most accurate information from which to determine whether cerebral palsy is likely to affect an individual infant born preterm. The sensitivity and specificity of that information is different between cranial ultrasound and MRI, depending on what approaches and sequences are used and the timing of the examinations. In this chapter we highlight the changing incidence of different patterns of brain injury in the preterm newborn and present a comparison of cranial ultrasound and MRI for predicting cerebral palsy in preterm infants affected by the commoner intracranial pathologies.

TRPM7 Mediates Neuronal Cell Death Upstream of Calcium/Calmodulin-Dependent Protein Kinase II and Calcineurin Mechanism in Neonatal Hypoxic-Ischemic Brain Injury

Transient receptor potential melastatin 7 (TRPM7), a calcium-permeable, ubiquitously expressed ion channel, is critical for axonal development, and mediates hypoxic and ischemic neuronal cell death in vitro and in vivo. However, the downstream mechanisms underlying the TRPM7-mediated processes in physiology and pathophysiology remain unclear. In this study, we employed a mouse model of hypoxic-ischemic brain cell death which mimics the pathophysiology of hypoxic-ischemic encephalopathy (HIE). HIE is a major public health issue and an important cause of neonatal deaths worldwide; however, the available treatments for HIE remain limited. Its survivors face life-long neurological challenges including mental retardation, cerebral palsy, epilepsy and seizure disorders, motor impairments, and visual and auditory impairments. Through a proteomic analysis, we identified calcium/calmodulin-dependent protein kinase II (CaMKII) and phosphatase calcineurin as potential mediators of cell death downstream from TRPM7 activation. Further analysis revealed that TRPM7 mediates cell death through CaMKII, calmodulin, calcineurin, p38, and cofilin cascade. In vivo, we found a significant reduction of brain injury and improvement of short- and long-term functional outcomes after HI after administration of specific TRPM7 blocker waixenicin A. Our data demonstrate a molecular mechanism of TRPM7-mediated cell death and identifies TRPM7 as a promising therapeutic and drug development target for HIE.

Profiling analysis reveals the potential contribution of long non-coding RNAs to preterm white matter injury

AIMS

The aim of this study was to investigate the molecular mechanism underlying preterm white matter injury (WMI) via the identification and functional analysis of differentially expressed long non-coding RNAs (lncRNAs) and mRNAs.

MAIN METHODS

A neonatal rat model of preterm WMI was established by ligating the common carotid artery and hypoxia induction. RNA sequencing was performed to analyze gene expression profiles of brain samples. Gene Ontology (GO) and Kyoto Encyclopedia of Genes (KEGG) analyses were performed to evaluate functions of target mRNAs. A co-expression network was generated to explore regulatory mechanisms.

KEY FINDINGS

In total, 210 lncRNAs and 619 mRNAs were differentially expressed between the preterm WMI group and the sham group. Based on GO and KEGG analyses, enriched pathways included the apoptotic signaling pathway, vascular endothelial growth factor (VEGF) signaling pathway, natural killer cell-mediated cytotoxicity pathway, and the autophagy pathway.

SIGNIFICANCE

Differentially expressed lncRNAs and mRNAs in the brain tissues of preterm WMI model were identified, and the biological processes were closely associated with the development of preterm WMI, thus being considered potential targets for future studies.

Multimodal assessment shows misalignment of structural and functional thalamocortical connectivity in children and adolescents born very preterm

Thalamocortical connections are altered following very preterm birth but it is unknown whether structural and functional alterations are linked and how they contribute to neurodevelopmental deficits. We used a multimodal approach in 27 very preterm and 35 term-born children and adolescents aged 10-16 years: Structural thalamocortical connectivity was quantified with two measures derived from probabilistic tractography of diffusion tensor data, namely the volume of thalamic segments with cortical connections and mean fractional anisotropy (FA) within the respective segments. High-density sleep EEG was recorded and sleep spindles were identified at each electrode. Sleep spindle density and integrated spindle activity (ISA) were calculated to quantify functional thalamocortical connectivity. In term-born participants, the volume of the global thalamic segment with cortical connections was strongly related to sleep spindles across the entire head (mean r ​= ​.53 ​± .10; range ​= ​0.35 to 0.78). Regionally, the volume of the thalamic segment connecting to frontal brain regions correlated with sleep spindle density in two clusters of electrodes over fronto-temporal brain regions (.42 ​± .06; 0.35 to 0.51 and 0.43 ​± .08; 0.35 to 0.62) and the volume of the thalamic segment connecting to parietal brain regions correlated with sleep spindle density over parietal brain regions (mean r ​= ​.43 ​± .07; 0.35 to 0.61). In very preterm participants, the volume of the thalamic segments was not associated with sleep spindles. In the very preterm group, mean FA within the global thalamic segment was negatively correlated with ISA over a cluster of frontal and temporo-occipital brain regions (mean r ​= ​-.53 ​± .07; -.41 to -.72). No association between mean FA and ISA was found in the term-born group. With this multimodal study protocol, we identified a potential misalignment between structural and functional thalamocortical connectivity in children and adolescents born very preterm. Eventually, this may shed further light on the neuronal mechanisms underlying neurodevelopmental sequelae of preterm birth.

Specific cognitive deficits in preschool age correlated with qualitative and quantitative MRI parameters in prematurely born children

BACKGROUND

Cognitive deficits after perinatal brain lesion in preterm infants are among the most common neurodevelopmental disturbances. The relationship between structural changes on at term magnetic resonance imaging (MRI) and cognitive deficits in the preschool age should be a special focus due to timely intervention. The aim of this study was to correlate qualitative and quantitative MRI parameters of perinatal brain lesion in preterm children, on early neonatal MRI and follow up MRI, with general and specific cognitive functions in the preschool age.

METHODS

Twenty-one preterm infants with verified perinatal lesions based on clinical and ultrasound data underwent a brain MRI at term-equivalent age and a second MRI between 3 and 5 years of age. Qualitative and quantitative MRI analyses were done. All subjects underwent cognitive assessment (3-5 years) using Wechsler Preschool and Primary Scale of Intelligence (WPPSI-III) and Developmental Neuropsychological Assessment (NEPSY-II).

RESULTS

Results show that many structural changes on at term MRI and on follow up MRI in preterm born children moderately correlate with specific cognitive deficits in preschool age. At term equivalent MRI, white matter changes and cortical thickness correlate to general and specific cognitive functions in infants born preterm. By analyzing follow up MRI at preschool age, structural changes of different white matter segments, corpus callosum, cortical thickness and lobe volume correlate to some specific cognitive functions.

CONCLUSION

Besides general cognitive delay, specific cognitive deficits in preterm children should be targeted in research and intervention, optimally combined with MRI scanning, providing timely and early intervention of cognitive deficits after perinatal brain lesion. Our results, as well as previously published results, suggest the importance of detailed preschool neuropsychological assessment, prior to enrolment in the school system. Although preliminary, our results expand our understanding of the relationship between early brain developmental lesions and cognitive outcome following premature birth.

Does ventricular volume affect the neurodevelopmental outcome in infants with intraventricular hemorrhage?

OBJECTIVE

The aim of this study is to investigate whether ventricular volume in posthemorrhagic ventricle dilatation impacts neurodevelopmental outcome. Infants were scanned with 3D cranial ultrasound in the first few months of life, and their neurodevelopmental outcome at 4, 8, 12, and 24 months corrected age (CA) was examined.

METHODS

Forty-nine infants who suffered an intraventricular hemorrhage (IVH) were enrolled in the study. Subjects were scanned multiple times during their stay in the neonatal intensive care unit. Images were manually segmented to measure total volume of the lateral ventricles, and the highest volume was taken. Infants with a volume ≤ 20 cc were considered low-volume (n = 33), and infants with a volume ≥ 40 cc were considered high-volume (n = 12). Developmental outcome was assessed at 4, 8, and 12 months CA with the Alberta Infant Motor Scale (AIMS) and Infant Neurological International Battery (Infanib), and at 24 months CA with the Bayley Scales of Infant Development 3e (BSID III).

RESULTS

Infants in the low-volume group had higher scores on the Infanib at 4 months CA, and on both the AIMS and Infanib at 8 and 12 months CA, even after controlling for gestational age, birth weight, and worst grade of IVH. We observed a trend where low-volume infants also scored higher on the cognitive and gross-motor subtests of the BSID III at 24 months CA.

CONCLUSION

Our results show that ventricular volume affects neurodevelopmental outcome in infants with IVH. This finding could guide the timing of future interventions, as earlier intervention may decrease the likelihood of adverse neurodevelopmental outcome.

Developmental dynamics of the periventricular parietal crossroads of growing cortical pathways in the fetal brain - In vivo fetal MRI with histological correlation

The periventricular crossroads have been described as transient structures of the fetal brain where major systems of developing fibers intersect. The triangular parietal crossroad constitutes one major crossroad region. By combining in vivo and post-mortem fetal MRI with histological and immunohistochemical methods, we aimed to characterize these structures. Data from 529 in vivo and 66 post-mortem MRI examinations of fetal brains between gestational weeks (GW) 18-39 were retrospectively reviewed. In each fetus, the area adjacent to the trigone of the lateral ventricles at the exit of the posterior limb of the internal capsule (PLIC) was assessed with respect to signal intensity, size, and shape on T2-weighted images. In addition, by using in vivo diffusion tensor imaging (DTI), the main fiber pathways that intersect in these areas were identified. In order to explain the in vivo features of the parietal crossroads (signal intensity and developmental profile), we analyzed 23 post-mortem fetal human brains, between 16 and ​40 GW of age, processed by histological and immunohistochemical methods. The parietal crossroads were triangular-shaped areas with the base in the continuity of the PLIC, adjacent to the germinal matrix and the trigone of the lateral ventricles, with the tip pointing toward the subplate. These areas appeared hyperintense to the subplate, and corresponded to a convergence zone of the developing external capsule, the PLIC, and the fronto-occipital association fibers. They were best detected between GW 25-26, and, at term, they became isointense to the adjacent structures. The immunohistochemical results showed a distinct cellular, fibrillar, and extracellular matrix arrangement in the parietal crossroads, depending on the stage of development, which influenced the MRI features. The parietal crossroads are transient, but important structures in white matter maturation and their damage may be indicative of a poor prognosis for a fetus with regard to neurological development. In addition, impairment of this region may explain the complex neurodevelopmental deficits in preterm infants with periventricular hypoxic/ischemic or inflammatory lesions.

Socioeconomic status and brain injury in children born preterm: modifying neurodevelopmental outcome

Improved intensive care therapies have increased the survival of children born preterm. Yet, many preterm children experience long-term neurodevelopmental sequelae. Indeed, preterm birth remains a leading cause of lifelong neurodevelopmental disability globally, posing significant challenges to the child, family, and society. Neurodevelopmental disability in children born preterm is traditionally linked to acquired brain injuries such as white matter injury and to impaired brain maturation resulting from neonatal illness such as chronic lung disease. Socioeconomic status (SES) has long been recognized to contribute to variation in outcome in children born preterm. Recent brain imaging data in normative term-born cohorts suggest that lower SES itself predicts alterations in brain development, including the growth of the cerebral cortex and subcortical structures. Recent evidence in children born preterm suggests that the response to early-life brain injuries is modified by the socioeconomic circumstances of children and families. Exciting new data points to the potential of more favorable SES circumstances to mitigate the impact of neonatal brain injury. This review addresses emerging evidence suggesting that SES modifies the relationship between early-life exposures, brain injury, and neurodevelopmental outcomes in children born preterm. Better understanding these relationships opens new avenues for research with the ultimate goal of promoting optimal outcomes for those children born preterm at highest risk of neurodevelopmental consequence.

The Life Course Consequences of Very Preterm Birth

Around 15 million children are born preterm (<37 weeks of gestation) every year. Of these, 15% or 2.25 million are born very preterm (VP; <32 weeks of gestation). Here, the developmental outcomes of VP babies in diverse domains from motor, cognitive, and social function to mental health and well-being throughout childhood and adolescence are reviewed. Their life course adaptation in terms of romantic relationships, employment, and quality of life into adulthood is also considered. Some adverse effects reduce as individuals age, and others remain remarkably stable from childhood into adulthood. We argue that to advance understanding of developmental mechanisms and direct resources for intervention more effectively, social factors need to be assessed more comprehensively, and genetically sensitive designs should be considered with neuroimaging integrated to test alternative developmental models. As current evidence is based almost exclusively on studies from high-income countries, research from low- and middle-income countries is urgently needed.

The most useful cranial ultrasound predictor of neurodevelopmental outcome at 2 years for preterm infants

AIM

To determine the most important cranial ultrasound predictors of abnormality associated with neurodevelopmental outcome at 2 years of age in preterm infants.

MATERIALS AND METHODS

A total of 343 preterm infants born between 2005 and 2010 and cared for in KK Women's and Children's Hospital, a tertiary paediatric hospital, with birth weight ≤1,250 g were assessed in this retrospective study. Serial cranial ultrasound examinations were examined for intraventricular haemorrhage and cystic periventricular leukomalacia. Ventricular-brain ratio on term equivalent cranial ultrasound was measured. Neurodevelopmental outcome was assessed by the performance on Bayley Scales of Infant and Toddler Development, 3^rd edition (Bayley-III) at 2 years corrected age. Mental delay was defined as having a combined Bayley-III score (the average of cognitive and language scores) <80.

RESULTS

The mean cognitive, language, and motor scores on Bayley-III in this cohort were 93±15, 83±18, and 92±15, respectively. Twenty-six percent of the preterm infants had mental delay and 4% had cerebral palsy. Ventricular-brain ratio >0.35 was the most significant factor associated with mental delay (odds ratio 5.28, 95% CI: 1.49-18.71, p=0.01). Other significant risk factors for mental delay were male gender, postnatal steroids, and necrotising enterocolitis, whereas maternal tertiary education was a protective factor against adverse outcome.

CONCLUSION

Ventricular-brain ratio >0.35 on term-equivalent cranial ultrasound in preterm infants is the strongest predictor for mental delay on Bayley score at 2 years of age.

Quantification of apparent axon density and orientation dispersion in the white matter of youth born with congenital heart disease

BACKGROUND

White matter alterations have previously been demonstrated in adolescents born with congenital heart disease (CHD) using diffusion tensor imaging (DTI). However, due to the non-specific nature of DTI metrics, it is difficult to interpret these findings in terms of their microstructural implications. This study investigated the use of neurite orientation dispersion and density imaging (NODDI), which involves the acquisition of advanced multiple b-value data over two shells and provides proxy measures of apparent axon density and orientation dispersion within white matter, as a complement to classic DTI measures.

STUDY DESIGN

Youth aged 16 to 24 years born with complex CHD and healthy peers underwent brain magnetic resonance imaging. White matter tract volumes and tract-average values of DTI and NODDI metrics were compared between groups. Tract-average DTI and NODDI results were spatially confirmed using tract-based spatial statistics.

RESULTS

There were widespread regions of lower tract-average neurite density index (NDI) in the CHD group as compared to the control group, particularly within long association tracts and in regions of the corpus callosum, accompanied by smaller white matter tract volumes and isolated clusters of lower fractional anisotropy (FA). There were no significant differences in orientation dispersion index (ODI) between groups.

CONCLUSION

Lower apparent density of axonal packing, but not altered axonal orientation, is a key microstructural factor in the white matter abnormalities observed in youth born with CHD. These impairments in axonal packing may be an enduring consequence of early life brain injury and dysmaturation and may explain some of the long-term neuropsychological difficulties experienced by this at-risk group.

Neurodevelopmental outcomes of children with congenital heart disease: A review

Congenital heart defects are the most common birth anomaly affecting approximately 1% of births. With improved survival in this population, there is enhanced ability to assess long-term morbidities including neurodevelopment. There is a wide range of congenital heart defects, from those with minimal physiologic consequence that do not require medical or surgical intervention, to complex structural anomalies requiring highly specialized medical management and intricate surgical repair or palliation. The impact of congenital heart disease on neurodevelopment is multifactorial. Susceptibility for adverse neurodevelopment increases with advancing severity of the defect with initial risk factors originating during gestation. Complex structural heart anomalies may pre-dispose the fetus to abnormal circulatory patterns in utero that ultimately impact delivery of oxygen rich blood to the fetal brain. Thus, the brain of a neonate born with complex congenital heart disease may be particularly vulnerable from the outset. That vulnerability is compounded during the newborn period and through childhood, as this population endures a myriad of medical and surgical interventions. For each individual patient, these factors are likely cumulative and synergistic with progression from fetal life through childhood. This review discusses the spectrum of risk factors that may impact neurodevelopment in children with congenital heart disease, describes current recommendations and practices for neurodevelopmental follow-up of children with congenital heart disease and reviews important neurodevelopmental trends in this high risk population.

Predicting developmental outcomes in preterm infants: A simple white matter injury imaging rule

OBJECTIVE

To develop a simple imaging rule to predict neurodevelopmental outcomes at 4.5 years in a cohort of preterm neonates with white matter injury (WMI) based on lesion location and examine whether clinical variables enhance prediction.

METHODS

Sixty-eight preterm neonates born 24-32 weeks' gestation (median 27.7 weeks) were diagnosed with WMI on early brain MRI scans (median 32.3 weeks). 3D T1-weighted images of 60 neonates with 4.5-year outcomes were reformatted and aligned to the posterior commissure-eye plane and WMI was classified by location: anterior or posterior-only to the midventricle line on the reformatted axial plane. Adverse outcomes at 4.5 years were defined as Wechsler Preschool and Primary Scale of Intelligence full-scale IQ <85, cerebral palsy, or Movement Assessment Battery for Children, second edition percentile <5. The prediction of adverse outcome by WMI location, intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD), and retinopathy of prematurity (ROP) was assessed using multivariable logistic regression.

RESULTS

Six children had adverse cognitive outcomes and 17 had adverse motor outcomes. WMI location predicted cognitive outcomes in 90% (area under receiver operating characteristic curve [AUC] 0.80) and motor outcomes in 85% (AUC 0.75). Adding IVH, BPD, and ROP to the model enhances the predictive strength for cognitive and motor outcomes (AUC 0.83 and 0.88, respectively). Rule performance was confirmed in an independent cohort of children with WMI.

CONCLUSIONS

WMI on early MRI can be classified by location to predict preschool age outcomes in children born preterm. The predictive value of this WMI classification is enhanced by considering clinical factors apparent by term-equivalent age.

Neurologic Examination Findings Associated With Small Cerebellar Volumes After Prematurity

To help clinicians understand what to expect from small cerebellar volumes after prematurity, this study aims to characterize the specific impacts of small cerebellar volumes on the infant neurologic examination. A prospective cohort of preterm newborns (<32 weeks' gestational age) had brain magnetic resonance imaging (MRI) studies at term-equivalent age. Cerebellar volumes were compared with neurologic examination findings in follow-up, adjusting for severity of intraventricular hemorrhage, white matter injury, and cerebellar hemorrhage. Deformation-based analyses delineated regional morphometric differences in the cerebellum associated with these findings. Of 119 infants with MRI scans, 109 (92%) had follow-up at 19.0±1.7 months corrected age. Smaller cerebellar volume at term was associated with increased odds of truncal hypotonia, postural instability on standing, and patellar hyperreflexia (P < .03). Small cerebellar volume defined as <19 cm³ by 40 weeks was associated with 7.5-fold increased odds of truncal hypotonia (P < .001), 8.9-fold odds postural instability (P < .001), and 9.7-fold odds of patellar hyperreflexia (P < .001). Voxel-based deformation-based morphometry showed postural instability associated with paravermian regions. Small cerebellar volume is associated with specific abnormalities on neurologic examination by 18 months of age, including truncal tone, reflexes, and postural stability.

Executive function deficits in children born preterm or at low birthweight: a meta-analysis

AIM

To investigate the magnitude of executive function deficits and their dependency on gestational age, sex, age at assessment, and year of birth for children born preterm and/or at low birthweight.

METHOD

PubMed, PsychINFO, Web of Science, and ERIC were searched for studies reporting on executive functions in children born preterm/low birthweight and term controls born in 1990 and later, assessed at a mean age of 4 years or higher. Studies were included if five or more studies reported on the same executive function measures.

RESULTS

Thirty-five studies (3360 children born preterm/low birthweight, 2812 controls) were included. Children born preterm/low birthweight performed 0.5 standardized mean difference (SMD) lower on working memory and cognitive flexibility and 0.4 SMD lower on inhibition. SMDs for these executive functions did not significantly differ from each other. Meta-regression showed that heterogeneity in SMDs for working memory and inhibition could not be explained by study differences in gestational age, sex, age at assessment, or year of birth.

INTERPRETATION

Children born preterm/low birthweight since 1990 perform half a SMD below term-born peers on executive function, which does not seem to improve with more recent advances in medical care or with increasing age.

WHAT THIS PAPER ADDS

Children born preterm/low birthweight perform below term-born children on core executive functions. Lower gestational age or male sex are not risk factors for poorer executive functions. Executive function difficulties in children born preterm/low birthweight remain stable across childhood. Executive function difficulties are similar for children born recently and children born in earlier eras.

Postoperative Pain Management in Pediatric Patients Undergoing Cardiac Surgery: Where Are We Heading?

OBJECTIVES

Adequate postoperative pain management is crucial in pediatric patients undergoing cardiac surgery because pain can lead to devastating short- and long-term consequences. This review discusses the limitations of current postoperative pain assessment and management in children after cardiac surgery, the obstacles to providing optimal treatment, and concepts to consider that may overcome these barriers.

DATA SOURCE

MEDLINE and PubMed.

CONCLUSIONS

Effective pain management in infants and young children undergoing cardiac surgery continues to evolve with innovative methods of both assessment and therapy using newer drugs or novel routes of administration. Artificial intelligence- and machine learning-based pain assessment and patient-tailored management in both pain measurement and prevention are already being integrated into the routine of current practice.

Quantitative Analysis of Punctate White Matter Lesions in Neonates Using Quantitative Susceptibility Mapping and R2* Relaxation

BACKGROUND AND PURPOSE

It is difficult to distinguish punctate white matter lesions from focal hemorrhagic lesions in neonates on conventional MR imaging because both kinds of lesions show increased signal intensity on T1-weighted images and, frequently, decreased signal intensity on T2-weighted images. Our aim was to distinguish punctate white matter lesions and focal hemorrhagic lesions using quantitative measures.

MATERIALS AND METHODS

In the current study, we acquired multiecho gradient recalled-echo MR imaging data from 24 neonates with hypoxic-ischemic encephalopathy and postprocessed them as R2* relaxation maps and quantitative susceptibility maps. Seven subjects who were found to have multifocal punctate white matter lesions and/or focal hemorrhagic lesions on R2* maps were included (mean gestational age at birth, 33 ± 4.28 weeks; mean gestational age at scanning, 38 ± 2 weeks). Manually drawing ROIs on R2* maps, we measured R2* and magnetic susceptibility values of the lesions, along with white matter regions within the corpus callosum as healthy comparison tissue.

RESULTS

R2* and magnetic susceptibility values were both found to easily distinguish punctate white matter lesions, focal hemorrhagic lesions, and healthy white matter tissue from each other (P < .05), with a large Hedge g. R2* and magnetic susceptibility values were significantly increased in focal hemorrhagic lesions compared with punctate white matter lesions and healthy white matter tissue. Punctate white matter lesions were also found to have significantly increased values over healthy white matter tissue.

CONCLUSIONS

R2* and quantitative susceptibility maps can be used to help clinicians distinguish and measure focal hemorrhages, punctate white matter lesions, and healthy white matter tissue.

Developmental outcomes of very preterm children with high parental education level

BACKGROUND

Compared to their term-born peers, children born very preterm are at risk for poorer cognitive, academic and behavioral outcomes, however this finding may have been confounded by lower parental education level in the very preterm children. Studies that compare very preterm and term-born children with comparable (high) parental education level are needed to assess the true effect of very preterm birth on outcomes.

AIMS

To compare cognitive, academic and behavioral functioning in very preterm and term-born children of highly educated parents. To examine whether outcomes differ for children of whom one or both parents are highly educated.

STUDY DESIGN

Cross-sectional study with a term-born comparison group.

SUBJECTS

113 very preterm children and 38 term-born children aged 8-12 years old, with highly educated parents.

MEASURES

Cognitive functioning (Intelligence Quotient), academic functioning (arithmetic facts and reading) and parent and teacher rated behavioral functioning (attention, executive function, hyperactivity, and emotional, conduct and peer problems). Parental education was considered high when children had two highly educated parents or one highly- and one middle educated parent.

RESULTS

Very preterm children had significantly poorer cognitive (difference of 10 IQ points) and behavioral functioning than their term-born peers, but did not differ on academic functioning. Children with one highly educated parent performed poorer than children with two highly educated parents on most outcome measures.

CONCLUSIONS

Performance of very preterm children should be compared to term-born peers with parents having comparable educational levels for accurate assessment of outcomes. The number of highly educated parents also impacts outcomes.

Low-grade intraventricular hemorrhage of preterm infants: neurodevelopmental and motor outcome

Intraventricular hemorrhage (IVH) is a main complication of prematurity, inversely associated with gestational age and birth weight. Low-grade IVH (I and II), diagnosed by cranial ultrasound, had long been considered rather not to affect neurodevelopmental and motor outcome, a view challenged by several literature reports. However, diversity in studies design, periods of subjects' collection, cohort characteristics, demographic data, maternal or neonatal comorbidities, neuroimaging methods, evaluation tools, short-or-long-term follow-up by the same or different examiners, as well as other parameters and confounders make comparisons among reports very difficult, not allowing solid conclusions. Older, but also newer investigations claim both possible outcomes: impairment or not of cognitive and motor abilities in very preterm infants with low-grade IVH. Thus, the current suggestion in the relevant literature is not to rely only on the results of cranial ultrasounds, but to also implement classic, or even more advanced MRI techniques at term equivalent age to preterm infants with grade I or II IVH. In addition, the continuation of close follow-up during school age is warranted.

Association of Socioeconomic Status and Brain Injury With Neurodevelopmental Outcomes of Very Preterm Children

IMPORTANCE

Studies of socioeconomic status and neurodevelopmental outcome in very preterm neonates have not sensitively accounted for brain injury.

OBJECTIVE

To determine the association of brain injury and maternal education with motor and cognitive outcomes at age 4.5 years in very preterm neonates.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort study of preterm neonates (24-32 weeks' gestation) recruited August 16, 2006, to September 9, 2013, at British Columbia Women's Hospital in Vancouver, Canada. Analysis of 4.5-year outcome was performed in 2018.

MAIN OUTCOMES AND MEASURES

At age 4.5 years, full-scale IQ assessed using the Wechsler Primary and Preschool Scale of Intelligence, Fourth Edition, and motor outcome by the percentile score on the Movement Assessment Battery for Children, Second Edition.

RESULTS

Of 226 survivors, neurodevelopmental outcome was assessed in 170 (80 [47.1%] female). Based on the best model to assess full-scale IQ accounting for gestational age, standardized β coefficients demonstrated the effect size of maternal education (standardized β = 0.21) was similar to that of white matter injury volume (standardized β = 0.23) and intraventricular hemorrhage (standardized β = 0.23). The observed and predicted cognitive scores in preterm children born to mothers with postgraduate education did not differ in those with and without brain injury. The best-performing model to assess for motor outcome accounting for gestational age included being small for gestational age, severe intraventricular hemorrhage, white matter injury volume, and chronic lung disease.

CONCLUSIONS AND RELEVANCE

At preschool age, cognitive outcome was comparably associated with maternal education and neonatal brain injury. The association of brain injury with poorer cognition was attenuated in children born to mothers of higher education level, suggesting opportunities to promote optimal outcomes.

Plasma cholesterol levels and brain development in preterm newborns

BACKGROUND

To assess whether postnatal plasma cholesterol levels are associated with microstructural and macrostructural regional brain development in preterm newborns.

METHODS

Sixty preterm newborns (born 24-32 weeks gestational age) were assessed using MRI studies soon after birth and again at term-equivalent age. Blood samples were obtained within 7 days of each MRI scan to analyze for plasma cholesterol and lathosterol (a marker of endogenous cholesterol synthesis) levels. Outcomes were assessed at 3 years using the Bayley Scales of Infant Development, Third Edition.

RESULTS

Early plasma lathosterol levels were associated with increased axial and radial diffusivities and increased volume of the subcortical white matter. Early plasma cholesterol levels were associated with increased volume of the cerebellum. Early plasma lathosterol levels were associated with a 2-point decrease in motor scores at 3 years.

CONCLUSIONS

Higher early endogenous cholesterol synthesis is associated with worse microstructural measures and larger volumes in the subcortical white matter that may signify regional edema and worse motor outcomes. Higher early cholesterol is associated with improved cerebellar volumes. Further work is needed to better understand how the balance of cholesterol supply and endogenous synthesis impacts preterm brain development, especially if these may be modifiable factors to improve outcomes.

A framework for multi-component analysis of diffusion MRI data over the neonatal period

We describe a framework for creating a time-resolved group average template of the developing brain using advanced multi-shell high angular resolution diffusion imaging data, for use in group voxel or fixel-wise analysis, atlas-building, and related applications. This relies on the recently proposed multi-shell multi-tissue constrained spherical deconvolution (MSMT-CSD) technique. We decompose the signal into one isotropic component and two anisotropic components, with response functions estimated from cerebrospinal fluid and white matter in the youngest and oldest participant groups, respectively. We build an orientationally-resolved template of those tissue components from data acquired from 113 babies between 33 and 44 weeks postmenstrual age, imaged as part of the Developing Human Connectome Project. These data were split into weekly groups, and registered to the corresponding group average templates using a previously-proposed non-linear diffeomorphic registration framework, designed to align orientation density functions (ODF). This framework was extended to allow the use of the multiple contrasts provided by the multi-tissue decomposition, and shown to provide superior alignment. Finally, the weekly templates were registered to the same common template to facilitate investigations into the evolution of the different components as a function of age. The resulting multi-tissue atlas provides insights into brain development and accompanying changes in microstructure, and forms the basis for future longitudinal investigations into healthy and pathological white matter maturation.

Preterm brain Injury: White matter injury

Despite the advances in neonatal intensive care, the preterm brain remains vulnerable to white matter injury (WMI) and disruption of normal brain development (i.e., dysmaturation). Compared to severe cystic WMI encountered in the past decades, contemporary cohorts of preterm neonates experience milder WMIs. More than destructive lesions, disruption of the normal developmental trajectory of cellular elements of the white and the gray matter occurs. In the acute phase, in response to hypoxia-ischemia and/or infection and inflammation, multifocal areas of necrosis within the periventricular white matter involve all cellular elements. Later, chronic WMI is characterized by diffuse WMI with aberrant regeneration of oligodendrocytes, which fail to mature to myelinating oligodendrocytes, leading to myelination disturbances. Complete neuronal degeneration classically accompanies necrotic white matter lesions, while altered neurogenesis, represented by a reduction of the dendritic arbor and synapse formation, is observed in response to diffuse WMI. Neuroimaging studies now provide more insight in assessing both injury and dysmaturation of both gray and white matter. Preterm brain injury remains an important cause of neurodevelopmental disabilities, which are still observed in up to 50% of the preterm survivors and take the form of a complex combination of motor, cognitive, and behavioral concerns.

MRI at term equivalent age for predicting long-term neurodevelopmental outcome in preterm infants - a cohort study

Purpose: Preterm infants are at increased risk of adverse neurodevelopmental outcome (NDO). Cranial ultrasound has limited predictability. The purpose of the study is to evaluate whether magnetic resonance imaging (MRI) done at term equivalent age (TEA) predicts NDO at 18-22 months of corrected gestational age (CGA).Materials and methods: This cohort study of preterm infants born at ≤32 weeks of gestation and/or birth weight <1500 grams between April 2011 and August 2012 was conducted in a tertiary care institute in India. MRI done at TEA was reported using objective scoring. NDO at 18-22-month CGA was assessed using Bayley Scale of Infant Development (BSID) version III. Composite score (CS) < 85 in motor, language, or cognition domain was taken as adverse NDO. Association between individual MRI subscores and NDO was evaluated using multiple linear regressions by backward elimination method. Validity of MRI abnormality in predicting adverse NDO was assessed.Results: Out of 94 infants who had MRI at TEA, 56 (60%) underwent BSID III. Mean gestational age was 29.8 ± 2.1 weeks. Median CS of all domains was lower with higher total MRI score. Predictive accuracy for various subscores ranged from 55 to 73%. By multiple regression analysis, signal abnormality was associated with motor delay (β -8.4; p .02) and cystic white matter (WM) changes with motor delay (β -7.3; p .003) and cognitive delay (β -6.1; p .005).Conclusions: Although specificity and negative predictive value were moderate to high across all subscores in MRI to predict the NDO, the accuracy has been only low to moderate, which limits its use as sole predictor.

Brain imaging in preterm infants <32 weeks gestation: a clinical review and algorithm for the use of cranial ultrasound and qualitative brain MRI

The aim is to review the evidence about the utility of term-equivalent age (TEA) magnetic resonance imaging (MRI) in predicting neurodevelopmental outcomes for preterm neonates. Preterm birth accounts for ~12% of all deliveries in the United States and is the leading cause of neurologic disabilities in children. From the neonatologist perspective, it is critically important to identify preterm infants at risk of subsequent neurodevelopmental disability who may benefit from early intervention services. However "the choose wisely campaign" also emphasizes the need to have ongoing cost/benefit discussions regarding care of preterm newborns to avoid waste that comes from subjecting infants to procedures that do not help. We performed a MEDLINE EMBASE database review from 2000 to 2018 to account for the technical evolution in the cranial ultrasound machines and introduction of MRI imaging in the NICU. Studies were graded based on the strength of their design using the GRADE guidelines and summarized with respect to brain MRI vs. cranial US (1) detection of white matter injury; (2) cerebellar hemorrhage; (3) long-term neurodevelopmental outcomes and impact on parental anxiety. We conclude with a hospital-specific guideline algorithm for performing TEA MRI based on risk evaluations ≤32 weeks.

White matter injury predicts disrupted functional connectivity and microstructure in very preterm born neonates

Objective

To determine whether the spatial extent and location of early-identified punctate white matter injury (WMI) is associated with regionally-specific disruptions in thalamocortical-connectivity in very-preterm born neonates.

Methods

37 very-preterm born neonates (median gestational age: 28.1 weeks; interquartile range [IQR]: 27–30) underwent early MRI (median age 32.9 weeks; IQR: 32–35), and WMI was identified in 13 (35%) neonates. Structural T1-weighted, resting-state functional Magnetic Resonance Imaging (rs-fMRI, n = 34) and Diffusion Tensor Imaging (DTI, n = 31) sequences were acquired using 3 T-MRI. A probabilistic map of WMI was developed for the 13 neonates demonstrating brain injury. A neonatal atlas was applied to the WMI maps, rs-fMRI and DTI analyses to extract volumetric, functional and microstructural data from regionally-specific brain areas. Associations of thalamocortical-network strength and alterations in fractional anisotropy (FA, a measure of white-matter microstructure) with WMI volume were assessed in general linear models, adjusting for age at scan and cerebral volumes.

Results

WMI volume in the superior (β = −0.007; p = .02) and posterior corona radiata (β = −0.01; p = .01), posterior thalamic radiations (β = −0.01; p = .005) and superior longitudinal fasciculus (β = −0.02; p = .001) was associated with reduced connectivity strength between thalamus and parietal resting-state networks. WMI volume in the left (β = −0.02; p = .02) and right superior corona radiata (β = −0.03; p = .008), left posterior corona radiata (β = −0.03; p = .01), corpus callosum (β = −0.11; p < .0001) and right superior longitudinal fasciculus (β = −0.02; p = .02) was associated with functional connectivity strength between thalamic and sensorimotor networks. Increased WMI volume was also associated with decreased FA values in the corpus callosum (β = −0.004, p = .015).

Conclusions

Regionally-specific alterations in early functional and structural network complexity resulting from WMI may underlie impaired outcomes.

•

Lesions in white matter pathways predicted altered functional connectivity.

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White matter lesions predicted alterations in white matter microstructure.

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Findings of lesion location and size were regionally-specific.

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White matter lesion size and location may underlie later delays in development.

Aberrant Structural Brain Connectivity in Adolescents with Attentional Problems Who Were Born Prematurely

BACKGROUND AND PURPOSE

Differences in structural brain connectivity that underlie inattention have been previously investigated in adolescents with attention deficit/hyperactivity disorder, but not in the context of premature birth, which is often associated with attentional problems. The purpose of this study was to identify the neural correlates of attentional problems in adolescents born prematurely and determine neonatal predictors of those neural correlates and attention problems.

MATERIALS AND METHODS

The study included 24 adolescents (12.5 ± 1.8 years of age; 12 girls, 12 boys) who were born prematurely and underwent MR imaging of the brain and cognitive assessment, both shortly after birth and as adolescents. Structural connectivity was assessed at adolescence using diffusion tensor imaging and tractography.

RESULTS

Of the 24 subjects, 12 had attention deficits. A set of axonal pathways connecting the frontal, parietal, temporal, and occipital lobes had significantly lower fractional anisotropy in subjects with attentional problems. The temporoparietal connection between the left precuneus and left middle temporal gyrus was the most significantly underconnected interlobar axonal pathway. Low birth weight and ventriculomegaly, but not white matter injury or intraventricular hemorrhage on neonatal MR imaging, predicted temporoparietal hypoconnectivity in adolescence. However, neither birth weight nor other neonatal characteristics were associated with attention deficits directly.

CONCLUSIONS

We identified an aberrant structural brain connectivity pattern, involving temporoparietal hypoconnectivity, in prematurely born adolescents with attentional problems. We also identified birth weight as a potential neonatal predictor of the temporoparietal hypoconnectivity. These findings add to our understanding of the neural basis and etiology of inattention in adolescents after premature birth.

White matter microstructure is associated with language in children born very preterm

Very preterm birth is associated with altered white matter microstructure and language difficulties, which may compromise communication, social function and academic achievement, but the relationship between these two factors is unclear. The aim of this study was to explore associations between white matter microstructure and language domains of semantics, grammar and phonological awareness at 7-years of age on a whole-brain level and within the arcuate fasciculus, an important language pathway, in very preterm and term-born children. Language was assessed in 145 very preterm-born (<30 weeks' gestation and/or <1250 g birth weight) and 33 term-born children aged 7 years. Fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), mean diffusivity (MD), axon orientation dispersion and axon density were estimated from diffusion magnetic resonance images also obtained at 7 years. The correlation between diffusion values and language was assessed using Tract-Based Spatial Statistics (TBSS). The arcuate fasciculus was delineated using constrained spherical deconvolution tractography and diffusion parameters from this tract were related to language measures using linear regression. While there was evidence for widespread associations between white matter microstructure and language, there was little evidence of differences in these associations between very preterm and term-born groups. TBSS analyses revealed that higher FA and lower AD, RD, and MD in major fibre tracts, including those subserving language, were associated with better semantic, grammar and phonological awareness performance. Higher axon density in widespread fibre tracts was also associated with better semantic performance. The tractography analyses of the arcuate fasciculus showed some evidence for associations between white matter microstructure and language outcomes. White matter microstructural organisation in widespread fibre tracts, including language-relevant pathways, was associated with language performance in whole-brain and tract-based analyses. The associations were similar for very preterm and term-born groups, despite very preterm children performing more poorly across language domains.

Inflammatory and Immune Proteins in Umbilical Cord Blood: Association with Hearing Screening Test Failure in Preterm Neonates

Objective

We aimed to determine whether elevated levels of various inflammatory and immune proteins in umbilical cord blood are associated with an increased risk of newborn hearing screening (NHS) test failure in preterm neonates.

Methods

This retrospective cohort study included 127 premature singleton infants who were born at ≤33.6 weeks. Umbilical cord plasma at birth was assayed for interleukin (IL)-6, complement C3a and C5a, matrix metalloproteinase (MMP)-9, macrophage colony-stimulating factor (M-CSF), and endostatin levels using ELISA kits. Neonatal blood C-reactive protein (CRP) levels were measured within 2 hours of birth. The primary outcome measure was a uni- or bilateral refer result on an NHS test. Univariate and multivariate analyses were applied.

Results

Fifteen (11.8%) infants failed the NHS test. In the univariate analyses, high IL-6 and low C3a levels in umbilical cord plasma, funisitis, and an elevated CRP level (>5 mg/L) in the immediate postnatal period were significantly associated with NHS test failure. However, the levels of umbilical cord plasma MMP-9, C5a, M-CSF, and endostatin were not significantly different between infants who passed and those who failed the NHS test. Multiple logistic regression analyses indicated that elevated umbilical cord plasma C3a levels were independently associated with a reduced risk of NHS test failure, whereas elevated levels of umbilical cord plasma IL-6 and high CRP levels in the immediate postnatal period were significantly associated with NHS test failure.

Conclusions

Our data demonstrated that in preterm neonates, a systemic fetal inflammatory response reflected by umbilical cord plasma IL-6 and immediate postnatal CRP levels may contribute to the risk for NHS test failure, whereas the changes in complement activation fragments initiated in utero may have protective effect of hearing screen failure.

Neuroimaging for Neurodevelopmental Prognostication in High-Risk Neonates

Predicting neurodevelopmental outcomes in high-risk neonates remains challenging despite advances in neonatal care. Early and accurate characterization of infants at risk for neurodevelopmental delays is necessary to best identify those who may benefit from existing early interventions and novel therapies that become available. Although neuroimaging is a promising biomarker in the prediction of neurodevelopmental outcomes in high-risk infants, it requires additional resources and expertise. Despite many advances in neonatal neuroimaging, there remain limitations in relating early neuroimaging findings with long-term outcomes; further studies are necessary to determine the optimal protocols to best identify high-risk patients and improve neurodevelopmental outcome prediction.

Early Diagnosis and Treatment of Cerebral Palsy in Children with a History of Preterm Birth

Infants born preterm are at increased risk of cerebral palsy (CP), with the risk increasing with decreasing gestational age. Although preterm children are at increased risk of CP compared with their term-born peers, most preterm children do not have CP and thus, it is important to have a standardized process for detecting those children at high risk of CP early. A combination of clinical history, neuroimaging, and physical examination is recommended to ensure early, accurate diagnosis. Early detection of CP is essential for timely early intervention to optimize outcomes for children and their families.

A fast segmentation-free fully automated approach to white matter injury detection in preterm infants

White matter injury (WMI) is the most prevalent brain injury in the preterm neonate leading to developmental deficits. However, detecting WMI in magnetic resonance (MR) images of preterm neonate brains using traditional WM segmentation-based methods is difficult mainly due to lack of reliable preterm neonate brain atlases to guide segmentation. Hence, we propose a segmentation-free, fast, unsupervised, atlas-free WMI detection method. We detect the ventricles as blobs using a fast linear maximally stable extremal regions algorithm. A reference contour equidistant from the blobs and the brain-background boundary is used to identify tissue adjacent to the blobs. Assuming normal distribution of the gray-value intensity of this tissue, the outlier intensities in the entire brain region are identified as potential WMI candidates. Thereafter, false positives are discriminated using appropriate heuristics. Experiments using an expert-annotated dataset show that the proposed method runs 20 times faster than our earlier work which relied on time-consuming segmentation of the WM region, without compromising WMI detection accuracy. Graphical Abstract Key Steps of Segmentation-free WMI Detection.

Outcomes After Acute Symptomatic Seizures in Children Admitted to a Neonatal Neurocritical Care Service

BACKGROUND

Neonatal seizures due to acute brain injury are associated with high rates of death, disability, and epilepsy. Our objective was to examine incidence of and risk factors for epilepsy among survivors of acute symptomatic neonatal seizures who were cared for by a neonatal neurocritical care service.

METHODS

Neonates with acute symptomatic seizures who were admitted to UCSF Benioff Children's Hospital Neuro-Intensive Care Nursery from July 2008 to June 2014 were considered for inclusion.

RESULTS

A total of 144 children with acute symptomatic seizures met study criteria and 37 (26%) died before age one. Eighty-seven children (85% of eligible survivors) were followed up to one year or longer. Epilepsy was diagnosed in eight children at median age 4.9 (interquartile range 1.7, 6.1) years. The cumulative incidence risk of epilepsy at one year was 2% (95% confidence interval 0.6% to 9%) and at five years was 7% (95% confidence interval 3% to 20%). Cerebral palsy was diagnosed in 21%. Bayley-III cognitive subscale less than 85 was present in 13%. Children with epilepsy were more likely to be preterm, have brain injury, and be discharged home on antiseizure medication, although the results were not significant after adjusted analysis.

CONCLUSIONS

The risk of epilepsy was lower and age at onset was older than in previous reports, which may be related to multiple factors including a neurocritical care approach, treatment of hypoxic-ischemic encephalopathy with hypothermia, high rate of neonatal transition to palliative care, and the exclusion of neonatal onset epilepsies. Continuation of antiseizure medications in infancy did not decrease the risk of epilepsy. Long-term, multicenter studies are needed to understand whether neonatal seizure management can alter the risk of epilepsy.

Association of Histologic Chorioamnionitis With Perinatal Brain Injury and Early Childhood Neurodevelopmental Outcomes Among Preterm Neonates

IMPORTANCE

Understanding the role of chorioamnionitis, a major factor leading to preterm birth, in the pathogenesis of neonatal brain injury and adverse neurodevelopmental outcomes may help in identifying potentially modifiable perinatal variables affecting brain health and outcomes among children born preterm.

OBJECTIVE

To evaluate whether histologic chorioamnionitis among neonates born very preterm is associated with intraventricular hemorrhage (IVH) and punctate white matter injury (WMI) or with adverse neurodevelopmental outcomes during early childhood.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort study conducted across 3 academic centers (from April 2006 to September 2013 in Canada, from March 2007 to March 2013 in the Netherlands, and from January 2004 to August 2011 in the United States). Children who were born preterm (24-32 weeks' gestation) and who had undergone a placental pathologic evaluation, magnetic resonance imaging as soon as clinically stable, and Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) assessments between 18 and 24 months' corrected age (CA) were included. Magnetic resonance imaging scans were assessed for grade of IVH and volume of punctate WMI. Data analysis occurred between December 2016 and January 2018. Final multivariable analyses examining the association of chorioamnionitis with motor and cognitive outcomes accounted for academic center and perinatal and postnatal factors.

MAIN OUTCOMES AND MEASURES

Punctate WMI volume and IVH detected on neonatal magnetic resonance imaging scans; motor and cognitive outcomes defined using Bayley-III assessments conducted among these children between 18 and 24 months' CA.

RESULTS

Of 350 neonates (182 male) in the final cohort, 145 (41.4%) had histologic chorioamnionitis. Gestational age was significantly lower among those with chorioamnionitis (median, 26.4 weeks; interquartile range [IQR], 25.6-27.7 weeks) than among those without chorioamnionitis (median, 28.0 weeks; IQR, 27.0-29.7 weeks). Chorioamnionitis was not associated with IVH or WMI, nor was it associated with worse motor outcomes in univariable or multivariable analyses (adjusted Bayley-III motor score, -2.2; 95% CI, -5.6 to 1.3). Cognitive scores were marginally yet statistically significantly lower among children with chorioamnionitis (median, 105; IQR, 95-110) than among those without chorioamnionitis (median, 105; IQR, 100-115) in the univariable model. This difference was attenuated in the multivariable model (adjusted Bayley-III cognitive score, -3.0; 95% CI, -6.4 to 0.4).

CONCLUSIONS AND RELEVANCE

Histologic chorioamnionitis was not associated with IVH or WMI near birth or with worse cognitive or motor outcomes from 18 to 24 months' CA after accounting for perinatal factors. Postnatal factors attenuated the association between chorioamnionitis and neurodevelopmental outcomes, highlighting the importance of preventing postnatal illness, such as infection, to promote optimal outcomes among children born preterm.

The neonatal brain in critical congenital heart disease: Insights and future directions

Neurodevelopmental outcomes are impaired in survivors of critical congenital heart disease (CHD) in several developmental domains including motor, cognitive and sensory outcomes. These deficits can extend into the adolescent and early adulthood years. The cause of these neurodevelopmental impairments is multi-factorial and includes patient specific risk factors, cardiac anatomy and physiology as well as brain changes seen on MRI. Advances in imaging techniques have identified delayed brain development in the neonate with critical CHD as well as acquired brain injury. These abnormalities are seen even before corrective neonatal cardiac surgery. This review focuses on describing brain changes seen on MRI in neonates with CHD, risk factors for these changes and the association with neurodevelopmental outcome. There is an emerging focus on the impact of cardiovascular physiology on brain health and the complex heart-brain interplay that influences ultimate neurodevelopmental outcome in these patients.

Preoperative cerebral hemodynamics from birth to surgery in neonates with critical congenital heart disease

BACKGROUND

Hypoxic-ischemic white matter brain injury commonly occurs in neonates with critical congenital heart disease. Recent work has shown that longer time to surgery is associated with increased risk for this injury. In this study we investigated changes in perinatal cerebral hemodynamics during the transition from fetal to neonatal circulation to ascertain mechanisms that might underlie this risk.

METHODS

Neonates with either transposition of the great arteries (TGA) or hypoplastic left heart syndrome (HLHS) were recruited for preoperative noninvasive optical monitoring of cerebral oxygen saturation, cerebral oxygen extraction fraction, and cerebral blood flow using diffuse optical spectroscopy and diffuse correlation spectroscopy, 2 noninvasive optical techniques. Measurements were acquired daily from day of consent until the morning of surgery. Temporal trends in these measured parameters during the preoperative period were assessed with a mixed effects model.

RESULTS

Forty-eight neonates with TGA or HLHS were studied. Cerebral oxygen saturation was significantly and negatively correlated with time, and oxygen extraction fraction was significantly and positively correlated with time. Cerebral blood flow did not significantly change with time during the preoperative period.

CONCLUSIONS

In neonates with TGA or HLHS, increasing cerebral oxygen extraction combined with an abnormal cerebral blood flow response during the time between birth and heart surgery leads to a progressive decrease in cerebral tissue oxygenation The results support and help explain the physiological basis for recent studies that show longer time to surgery increases the risk of acquiring white matter injury.

Magnetic resonance spectroscopy in preterm infants: association with neurodevelopmental outcomes

OBJECTIVE

To compare magnetic resonance spectroscopy (MRS) metabolite ratios in preterm infants at term-equivalent age with those in term infants and to evaluate the association between MRS metabolites and neurodevelopmental outcomes at 18 months corrected age in preterm infants.

DESIGN

We studied infants born at a gestational age <37 weeks and weighing <1500 g during 2009-2013 using MRS at term-equivalent age. Infants with major brain abnormalities were excluded. The ratios of N-acetylaspartate (NAA) to creatine (Cre), NAA to choline-containing compounds (Cho) and Cho to Cre in the frontal white matter and thalamus were measured using multivoxel point-resolved proton spectroscopy sequence. Neurodevelopmental outcomes were assessed at 18 months corrected age.

RESULTS

Thirty-three preterm infants and 16 term infants were enrolled in this study. Preterm infants with normal development at 18 months showed significantly lower NAA/Cho ratios in the frontal white matter than term infants. There were no differences in the Cre/Cho ratios between preterm and term infants. At 18 months corrected age, 9 preterm infants with a mild developmental delay showed significantly lower NAA/Cho ratios in the thalamus than 24 preterm infants with normal development.

CONCLUSIONS

Preterm infants at term-equivalent age showed reduced MRS metabolites (NAA/Cho) compared with term infants. Decreased NAA/Cho ratios in the thalamus were associated with neurodevelopmental delay at 18 months corrected age in preterm infants.

Multiple Postnatal Infections in Newborns Born Preterm Predict Delayed Maturation of Motor Pathways at Term-Equivalent Age with Poorer Motor Outcomes at 3 Years

OBJECTIVES

To evaluate whether the number of postnatal infections is associated with abnormal white matter maturation and poorer motor neurodevelopmental outcomes at 36 months of corrected age.

STUDY DESIGN

A prospective longitudinal cohort study was undertaken of 219 newborns born preterm at 24-32 weeks of gestational age recruited between 2006 and 2013 with magnetic resonance imaging of the brain both early in life and at term-equivalent age. Postnatal infection was defined as any clinical infection or positive culture ≥72 hours after birth. White matter maturation was assessed by magnetic resonance spectroscopic imaging, magnetic resonance diffusion tensor imaging, and tract-based spatial statistics. Neurodevelopmental outcomes were assessed in 175 (82% of survivors) infants with Bayley Scales of Infant and Toddler Development-III composite scores and Peabody Developmental Motor Scales at 35 months of corrected age (IQR 34-37 months). Infection groups were compared via the Fisher exact test, Kruskal-Wallis test, and generalized estimating equations.

RESULTS

Of 219 neonates born preterm (median gestational age 27.9 weeks), 109 (50%) had no postnatal infection, 83 (38%) had 1 or 2 infections, and 27 (12%) had ≥3 infections. Infants with postnatal infections had more cerebellar hemorrhage. Infants with ≥3 infections had lower N-acetylaspartate/choline in the white matter and basal ganglia regions, lower fractional anisotropy in the posterior limb of the internal capsule, and poorer maturation of the corpus callosum, optic radiations, and posterior limb of the internal capsule on tract-based spatial statistics analysis as well as poorer Bayley Scales of Infant and Toddler Development-III (P = .02) and Peabody Developmental Motor Scales, Second Edition, motor scores (P < .01).

CONCLUSIONS

In newborns born preterm, ≥3 postnatal infections predict impaired development of the motor pathways and poorer motor outcomes in early childhood.