Preterm Brain Injury and Neurodevelopmental Outcomes: A Meta-analysis

Intraventricular Hemorrhage and Survival, Multimorbidity, and Neurodevelopment

Importance

Intraventricular hemorrhage (IVH) has proven to be a challenging and enduring complication of prematurity. However, its association with neurodevelopment across the spectrum of IVH severity, independent of prematurity, and in the context of contemporary care remains uncertain.

Objective

To evaluate national trends in IVH diagnosis and the association with survival and neurodevelopmental outcomes at 2 years of age.

Design, Setting, and Participants

This whole-population cohort study was conducted using data from the UK National Neonatal Research Database. Infants born at less than 29 weeks' gestation with any grade of IVH between January 2013 and December 2019 in England were included and matched with controls. Data analysis occurred from November 2023 to June 2024.

Exposure

IVH grades 1 to 4 (Papile classification).

Main Outcomes and Measures

The primary outcome was survival without severe neurodevelopmental impairment (NDI) at 2 years' corrected age including severe delays (inability to understand or use >5 words or signs; being unable to walk, sit, or use hands; blindness; or uncorrectable hearing impairment). Secondary outcomes included gross and fine motor function, receptive and expressive communication, vision, hearing, and overall developmental progress. Outcomes were derived from clinician-entered data and analyzed using multiple logistic regression.

Results

Between 2013 and 2019, of 26 756 infants born at less 29 weeks' gestation in England, 8461 received a diagnosis of IVH (5570 low-grade and 2891 high-grade, and 8328 were included in the study. Overall, 5519 included infants had low-grade IVH with a median [IQR] gestational age of 26 (25-27) weeks, of which 2477 (48.88%) were male. Of the 2809 included infants with high-grade IVH, the median (IQR) gestational age was 25 (24-26) weeks and 1710 (60.88%) were male. The mean (SD) incidence of high-grade IVH (108 [6.7] per 1000 live extremely preterm births) and low-grade IVH (208 [10.4] per 1000 live extremely preterm births) increased between 2013 and 2019, although this did not reach statistical significance for high-grade IVH. Survival without severe NDI decreased significantly after high-grade IVH (a 74% reduction; aOR, 0.26; 95% CI, 0.22-0.31), and to a lesser extent after low-grade IVH (a 12% reduction; aOR, 0.88; 95% CI, 0.79-0.98). Although low-grade IVH was associated with functional impairments, most survivors, 2283 of 4379 infants (52.15%), had no NDI, and the association with NDI was accounted for by grade 2 IVH. Decreased survival without severe NDI was observed with increasing grade of IVH, decreasing gestation, bilateral compared to unilateral injuries, and increasing morbidity count (severe retinopathy of prematurity, bronchopulmonary dysplasia, and surgical necrotizing enterocolitis). Impairments in gross motor function and communication were common, especially among those with high-grade IVH (with prevalences of 44.55% [715 of 1605 infants] and 48.91% [784 of 1603 infants], respectively).

Conclusions and Relevance

In this cohort study, IVH was highlighted as a persistent issue with substantial neurodevelopmental implications despite advances in care. This study offers useful data for counseling families; however, follow-up to school age is necessary to grasp the full impact of these injuries on children's lives.

Diagnostic accuracy of early neonatal MRI in predicting adverse motor outcomes in children born preterm: Systematic review and meta-analysis

AIM

To examine the diagnostic accuracy of Early structural and diffusion-weighted magnetic resonance imaging (MRI) (acquired at < 36 weeks postmenstrual age) to detect cerebral palsy (CP) or other adverse motor outcomes at or beyond 3 years corrected age in infants born preterm.

METHOD

In this systematic review and meta-analysis, we searched the CINAHL, Embase, PubMed, and Web of Science databases for studies without language restrictions and a prospectively registered protocol up to October 2023. We extracted the study details, associations presented, and meta-analyses conducted with pooled sensitivity and specificity.

RESULTS

Twenty-seven articles met the overall inclusion criteria. White matter injury, cerebellar haemorrhage, intraventricular haemorrhage, and lower thalamic volume were associated with poorer motor outcomes. Abnormal Early structural MRI detected infants with a later diagnosis of CP (n = 448, eight studies) with a pooled sensitivity of 98% (95% confidence interval [CI] = 86-100), specificity of 75% (95% CI = 51-93), and adverse motor outcomes (n = 215, four studies), with a pooled sensitivity of 39% (95% CI = 20-59) and a specificity of 90% (95% CI = 88-94).

INTERPRETATION

Early abnormal structural MRI predicted later CP with high sensitivity and specificity, while specificity was higher than sensitivity in predicting adverse motor outcomes using the Movement Assessment Battery for Children, Second Edition. Further research into diagnostic accuracy and association between Early MRI and long-term motor outcomes is warranted.

Feasibility and safety of autologous cord blood derived cell administration in extremely preterm infants: a single-centre, open-label, single-arm, phase I trial (CORD-SaFe study)

BACKGROUND

Evidence from preclinical studies in small and large animal models has shown neuroprotective effects of intravenous administration of umbilical cord blood derived cells (UCBCs). This study aimed to evaluate the feasibility of umbilical cord blood (UCB) collection, extraction of UCBCs, and subsequent safety of intravenous autologous administration of UCBCs in extremely preterm infants (born <28 weeks gestation).

METHODS

A single-centre, open-label, single-arm, safety and feasibility clinical intervention trial was conducted at Monash Medical Centre and Monash Children's Hospital, Melbourne, Australia. Participants were extremely preterm infants born at less than 28 weeks completed gestation, and exclusions included major congenital malformation, maternal blood-borne virus infection, and severe brain injury on postnatal cranial ultrasound. UCB was collected at birth, and UCBCs were characterised (total nucleated cell count (TNC), mononuclear cell count (MNC), CD34+ cell count) and cryopreserved. Infants were reinfused with autologous UCBCs (25-50 million MNCs/kg) intravenously in the second postnatal week. Primary outcomes included feasibility: sufficient UCB volume (>7 mL) and UCBC numbers following processing (>25 × 106 TNCs/kg); and safety: absence of adverse events directly related to UCBC administration.

FINDINGS

Forty-four UCB collections were attempted and sufficient UCB volume/UCBC extraction was demonstrated in 37 (84.1%) infants. Good Manufacturing Practice (GMP) grade cells were obtained in 31/44 (70.4%) of infants. Median (IQR) TNCs and MNCs collected were 130 (67-207) x 106/kg and 60 (39-105) x 106/kg, respectively. 23 infants with median (IQR) gestation of 26 (24-27) weeks and birth weight of 761 (650-946) grams were administered cells at a median (IQR) dose of 42.3 (31.1-62.3) x 106 MNCs/kg). No serious adverse events were noted, and the infusions were well-tolerated.

INTERPRETATION

This phase-1 clinical trial has shown UCBC collection and reinfusion was feasible in approximately 70% of extremely preterm infants and was well tolerated without any serious adverse events.

FUNDING

Funding to support this study was obtained from National Health and Medical Research Council of Australia, Cerebral Palsy Alliance, National Stem Cell Foundation of Australia, and Lions Cord Blood Foundation.

Risk Factors for Hearing Screen Failure in a Single-Family Room Neonatal Intensive Care Unit

OBJECTIVE

 This study aimed to determine hearing screen outcomes and identify clinical and environmental risk factors for hearing screen failure in very preterm infants at a level IV single-family room (SFR) neonatal intensive care unit (NICU).

STUDY DESIGN

 We conducted a retrospective study of infants <33 weeks gestational age admitted to a level IV SFR NICU who survived to discharge and had automated auditory brainstem response results available. Demographics, antenatal and postnatal factors, and respiratory support modes and their duration were collected from the electronic medical record.

RESULTS

 Of 425 eligible infants with documented hearing screen results, 353 (83%) passed and 72 (17%) failed the hearing screen (unilateral, N = 44 [61%]; bilateral, N = 28 [39%]). Compared to infants who passed the hearing screen, infants with hearing screen failure were lower gestational age and birth weight, male sex, were screened at later postnatal and postmenstrual ages (PMAs), had lower 1- and 5-minute Apgar scores, longer duration of furosemide therapy, early hypotension, intraventricular hemorrhage (IVH) ≥Grade 3, and bronchopulmonary dysplasia (BPD) at 36 weeks PMA. Infants with hearing screen failure experienced longer exposures to invasive and noninvasive respiratory support. Heated, humidified, high flow nasal cannula >2 liters per minute exposure was significantly longer in infants with bilateral hearing screen failure (18.4 ± 18.4 d) compared to duration in infants who passed (7.4 ± 12.8 d) and those with unilateral failure (9 ± 13 d), (mean ± standard deviation [SD], p < 0.001). In the final logistic model, IVH ≥Grade 3 (odds ratio [OR] = 3.22, 95% confidence interval [CI]: 1.15-8.98, p = 0.026) and BPD (OR = 2.27, 95% CI: 1.25-4.11, p = 0.007) were the factors with the greatest risk for hearing screen failure.

CONCLUSION

 We speculate that the association of BPD with hearing screen failure may be mediated, in part, by chronic noise exposure, including from respiratory support devices. Attention to hearing protection in at-risk infants during respiratory support may mitigate the risk of hearing loss.

KEY POINTS

· NICU noise often exceeds recommended sound levels.. · Seventeen percent of infants with <33 weeks GA in SFR NICU failed hearing screenings.. · BPD and IVH are risk factors for hearing screen failure.. · Respiratory devices contribute to increased NICU noise.. · hearing protection should be considered during respiratory support..

Neonatal intracranial pathologies on ultrasound imaging in sub-Saharan Africa: a systematic review and meta-analysis

Annually, 30 million children are affected by newborn conditions, most in low-income countries, with long-term implications for survivors. We aimed to evaluate neonatal intracranial pathologies identifiable on cranial ultrasound (CUS) in sub-Saharan Africa (SSA). This systematic review and meta-analysis explored the spectrum of neonatal intracranial pathology, in nine databases, using the Joanna Briggs Institute Systematic Review Tools. The review was registered with PROSPERO (CRD42022309249). In total, 92 studies from 14 countries were identified, with South Africa (34%) and Nigeria (28%) most represented. Of these, 38 (42%) focused on intraventricular haemorrhage (IVH), 13 (14%) on congenital brain anomalies, 11 (12%) on intracranial infection, 9 (10%) on ventriculomegaly/hydrocephalus, and 7 (8%) on neonatal encephalopathy. IVH pooled prevalence was 29% (CI 23-35%), with a quarter high-grade (24%, CI 20-29%). Higher prevalence was seen at lower gestation (<32 weeks, 38% (CI 26-50%)) and birthweight (<1500 g, 32% (CI 24-40%)). Periventricular leukomalacia was less common than IVH (9% (CI 6-13%)). A spectrum of intracranial pathology has been reported on neonatal CUS from SSA. IVH affected close to one third of at-risk neonates, and PVL one in eleven, with potentially important implications for longer term outcomes for affected children. IMPACT: Newborn conditions, like prematurity and neonatal encephalopathy, are leading causes of under-5 child mortality, with the greatest burden in sub-Saharan Africa. Intracranial pathologies relating to newborn conditions, may have important long-term consequences, yet frequently go undetected in settings with limited access to imaging. We examined the spectrum and prevalence of different neonatal intracranial pathologies detectable on cranial ultrasound imaging from the sub-Saharan Africa region. A wide spectrum of intracranial pathology was reported, including a high prevalence of intraventricular haemorrhage and periventricular leukomalacia among small and preterm neonates, with potential important implications for childhood outcomes.

Association of a Count of Inpatient Morbidities with 2-Year Outcomes among Infants Born Extremely Preterm

OBJECTIVE

To determine if number of neonatal morbidities is associated with death or severe neurodevelopmental impairment (sNDI) among infants born extremely preterm who survived to 36 weeks' postmenstrual age (PMA).

STUDY DESIGN

This is a retrospective cohort analysis of prospectively collected data from 15 NICHD Neonatal Research Network centers. Neonatal morbidities and 2-year outcomes were examined for 3794 infants born at 22 to 26 weeks' gestation from 2014 through 2019 who survived to 36 weeks' PMA.

RESULTS

Serious brain injury (SBI), bronchopulmonary dysplasia (BPD), and severe retinopathy of prematurity (ROP) had the strongest bivariate associations with death or sNDI (ORs, 95% CI): 3.96 (3.39, 4.64), 3.41 (2.94, 3.95), and 2.66 (2.28, 3.11)], respectively. A morbidity count variable was constructed using these morbidities. The estimated ORs and 95% CI for death or sNDI with any 1, any 2, or all 3 of these morbidities, adjusted for maternal and infant characteristics and hospital of birth, increased from 2.75 (2.25, 3.37) to 6.10 (4.83, 7.70) to 12.90 (9.07, 18.36), respectively. Corresponding rates of late death or sNDI with none, any 1, any 2, and all 3 morbidities were 12.6%, 30.3%, 51.9%, and 69.9%, respectively. The estimated logistic model produced predictions of death or sNDI with moderate discrimination (C-statistic [95% CI]: 0.765 [0.749, 0.782]) and good calibration (Intercept [CITL] = -0.004, slope = 1.026).

CONCLUSIONS

Among infants born extremely preterm who survived to 36 weeks' PMA, a count of SBI, BPD, and severe ROP predicts death or sNDI.

TRIAL REGISTRATION

ClinicalTrials.gov ID Generic Database: NCT00063063.

Association between Slow and Rapid Weight Gain before 36 Weeks of Corrected Age and 6-Year-Developmental Quotient in Infants Born at <26 Weeks of Gestation

OBJECTIVE

 The postnatal growth of preterm infants is influenced by various factors; however, the association between growth and long-term outcomes in extremely preterm infants remains unclear. Therefore, we aimed to determine the association between 6-year development and body weight (BW) at 36 weeks of corrected age (CA) in extremely preterm infants.

STUDY DESIGN

 We conducted a retrospective observational study including extremely preterm infants born at < 26 weeks of gestation. We defined the key standard deviation score (SDS) using BW at birth and evaluated the association between BW-related values at 36 weeks of CA and the 6-year developmental quotient (DQ).

RESULTS

 This study included 90 infants. The absolute difference between changes in the BW SDS from birth and the median changes in DQ ≥ 85 infants was significantly greater in infants with a DQ < 85 than ≥85 (median [interquartile range]: 0.80 [0.29, 1.31] vs. 0.34 [0.13, 0.55]; p = 0.001). After adjustment by the logistic regression analysis for DQ < 85, the absolute difference was statistically significant (odds ratio: 4.99, 95% confidence interval: 1.71-14.5). The correlation coefficient between the absolute difference and DQ was -0.35 (p < 0.001). There were no significant associations between a DQ < 85 and SDS or changes in SDS from birth.

CONCLUSION

 For infants born at <26 weeks of gestation, slow and rapid weight gain were associated with a low 6-year DQ when using values representing individual body sizes at birth. Individual backgrounds should be considered to avoid both slow and rapid weight gain for the growth management of these infants for at least up to 36 weeks of CA. Further research is needed to determine which body size has a positive impact on the long-term outcomes of infants.

KEY POINTS

· The median change in BW SDS was a key factor for DQ.. · Slow/rapid weight gain were related to a low 6-year DQ.. · Individual backgrounds may be important in neonatal intensive care unit care..

Circadian patterns of heart rate variability in fetal sheep after hypoxia-ischaemia: A biomarker of evolving brain injury

Hypoxia-ischaemia (HI) before birth is a key risk factor for stillbirth and severe neurodevelopmental disability in survivors, including cerebral palsy, although there are no reliable biomarkers to detect at risk fetuses that may have suffered a transient period of severe HI. We investigated time and frequency domain measures of fetal heart rate variability (FHRV) for 3 weeks after HI in preterm fetal sheep at 0.7 gestation (equivalent to preterm humans) until 0.8 gestation (equivalent to term humans). We have previously shown that this is associated with delayed development of severe white and grey matter injury, including cystic white matter injury (WMI) resembling that observed in human preterm infants. HI was associated with suppression of time and frequency domain measures of FHRV and reduced their circadian rhythmicity during the first 3 days of recovery. By contrast, circadian rhythms of multiple measures of FHRV were exaggerated over the final 2 weeks of recovery, mediated by a greater reduction in FHRV during the morning nadir, but no change in the evening peak. These data suggest that the time of day at which FHRV measurements are taken affects their diagnostic utility. We further propose that circadian changes in FHRV may be a low-cost, easily applied biomarker of antenatal HI and evolving brain injury. KEY POINTS: Hypoxia-ischaemia (HI) before birth is a key risk factor for stillbirth and probably for disability in survivors, although there are no reliable biomarkers for antenatal brain injury. In preterm fetal sheep, acute HI that is known to lead to delayed development of severe white and grey matter injury over 3 weeks, was associated with early suppression of multiple time and frequency domain measures of fetal heart rate variability (FHRV) and loss of their circadian rhythms during the first 3 days after HI. Over the final 2 weeks of recovery after HI, exaggerated circadian rhythms of frequency domain FHRV measures were observed. The morning nadirs were lower with no change in the evening peak of FHRV. Circadian changes in FHRV may be a low-cost, easily applied biomarker of antenatal HI and evolving brain injury.

Investigation of the catch-up status and termination for corrected age of neurodevelopment in premature infants of different gestational ages

Background

Corrected age entails determining the age of premature infants by adjusting their gestational age to 40 weeks. Research on corrected age in relation to neurodevelopment is limited, both domestically and internationally, resulting in a lack of consensus and recommendations regarding the appropriate termination of the neurodevelopmental corrected age. This study aimed to assess the neurodevelopmental catch-up status of premature infants with varying gestational ages and to identify appropriate termination criteria for the corrected age of neurodevelopment.

Methods

The study included 1,579 premature infants without high-risk factors and 8,441 full-term infants receiving care at the child health clinics of the Second Affiliated Hospital of Army Medical University, Chongqing Health Center for Women and Children, and Maternal and Child Health Care Hospital of Wanzhou District, Chongqing between January 1, 2018, and March 1, 2023. Infants were grouped based on gestational age into early, middle, and late premature infants, as well as full-term infants. Over a 48-month period, the developmental quotient (DQ) of each functional area on the Gesell Developmental Scale was compared across groups.

Results

There were no statistically significant differences in DQ of all functional areas between late premature infants and full-term infants at 36 months of age (all P>0.05). In contrast, some developmental functional areas in middle- and early-premature infants and full-term infants exhibited significant differences at 36 months of age; however, by 48 months of age, these differences were no longer significant (all P>0.05). The DQ of all functional areas in the late, middle, and early premature infant groups demonstrated a catch-up trend from 6 to 48 months of chronological age (all P<0.05).

Conclusions

The termination age for neurodevelopmental correction in premature infants may continue beyond 36 months of age, with longer correction time required for those born at younger gestational ages.

Early neurodevelopmental outcomes of preterm infants with intraventricular haemorrhage and periventricular leukomalacia

AIM

Intraventricular haemorrhage (IVH) and periventricular leukomalacia (PVL) in preterm infants are associated with an increased risk of long-term neurodevelopmental impairments (NDI) and cerebral palsy (CP). However, little is known about their impact on early neurodevelopmental outcomes despite increasing evidence highlighting the feasibility and importance of early NDI/CP diagnosis. We aimed to determine the early neurodevelopmental outcomes of preterm infants with IVH and PVL.

METHODS

This was a retrospective single-centre cohort study of preterm infants born at <29 weeks gestation or <1000 g birth weight who attended an Early Neurodevelopment Clinic at 3 to 4 months of corrected age. Primary outcomes of early NDI and CP/high-risk CP diagnoses based on Prechtl's General Movements Assessment and the Hammersmith Infant Neurological Examination were compared between infants without IVH and infants with mild IVH (grades I-II), severe IVH (grades III-IV), and severe brain injury (SBI; severe IVH or cystic PVL).

RESULTS

Of 313 infants, 52.1% (n = 163), 41.2% (n = 129), 6.7% (n = 21) and 8.6% (n = 27) had no IVH, mild IVH, severe IVH and SBI, respectively. The adjusted odds of early CP/high-risk CP diagnosis were significantly higher in infants with severe IVH (aOR 6.07, 95% CI 1.50-24.50) and SBI (aOR 15.28, 95% CI 3.70-63), but not in those with mild IVH (aOR 1.24, 95% CI 0.49-3.10). However, the adjusted odds of any early NDI were similar across groups.

CONCLUSION

Preterm infants with severe IVH and SBI are at increased risk of early CP/high-risk of CP diagnosis at 3 to 4 months of corrected age.

Ganaxolone Therapy After Preterm Birth Restores Cerebellar Oligodendrocyte Maturation and Myelination in Guinea Pigs

The postnatal environment is challenging for the preterm neonate with exposure to hypoxic and excitotoxic events, amplified by premature loss of placentally derived neurosteroids. Between preterm birth and term equivalent age (TEA), cerebellar development continues despite these challenges. We hypothesize that neurosteroid replacement therapy during this time will support optimal cerebellar development. Guinea pig sows delivered at term (∼69 days gestation) or were induced to deliver preterm (∼62 days), with preterm pups receiving ganaxolone or vehicle until TEA. Postnatal assessments comprised salivary cortisol (corrected postnatal age [CPA] 0, 7, 38), behavioral analysis (CPA7, 38), and tissue collection (CPA0 and CPA40). Neurodevelopmental markers (MBP, Olig2, and NeuN) were assessed in the cerebellum by immunohistochemistry, whereas RT-PCR was utilized to investigate key inhibitory/excitatory pathways and oligodendrocyte lineage markers. Following preterm birth, there was evidence of a hyperactive phenotype, increased salivary cortisol concentrations, and impaired myelination and oligodendrocyte maturation at the protein level. mRNA expressions of key inhibitory/excitatory pathways and myelin stability were also altered following preterm birth. Importantly, we showed that neurosteroid replacement therapy returns cerebellar development and behavior toward a term-like phenotype. Therefore, ganaxolone may reduce the vulnerability of the cerebellum to postnatal challenges arising from preterm birth.

Multilabel SegSRGAN-A framework for parcellation and morphometry of preterm brain in MRI

Magnetic resonance imaging (MRI) is a powerful tool for observing and assessing the properties of brain tissue and structures. In particular, in the context of neonatal care, MR images can be used to analyze neurodevelopmental problems that may arise in premature newborns. However, the intrinsic properties of newborn MR images, combined with the high variability of MR acquisition in a clinical setting, result in complex and heterogeneous images. Segmentation methods dedicated to the processing of clinical data are essential for obtaining relevant biomarkers. In this context, the design of quality control protocols for the associated segmentation is a cornerstone for guaranteeing the accuracy and usefulness of these inferred biomarkers. In recent work, we have proposed a new method, SegSRGAN, designed for super-resolution reconstruction and segmentation of specific brain structures. In this article, we first propose an extension of SegSRGAN from binary segmentation to multi-label segmentation, leading then to a partitioning of an MR image into several labels, each corresponding to a specific brain tissue/area. Secondly, we propose a segmentation quality control protocol designed to assess the performance of the proposed method with regard to this specific parcellation task in neonatal MR imaging. In particular, we combine scores derived from expert analysis, morphometric measurements and topological properties of the structures studied. This segmentation quality control can enable clinicians to select reliable segmentations for clinical analysis, starting with correlations between perinatal risk factors, regional volumes and specific dimensions of cognitive development. Based on this protocol, we are investigating the strengths and weaknesses of SegSRGAN and its potential suitability for clinical research in the context of morphometric analysis of brain structure in preterm infants, and to potentially design new biomarkers of neurodevelopment. The proposed study focuses on MR images from the EPIRMEX dataset, collected as part of a national cohort study. In particular, this work represents a first step towards the design of 3-dimensional neonatal brain morphometry based on segmentation. The (free and open-source) code of multilabel SegSRGAN is publicly available at the following URL: https://doi.org/10.5281/zenodo.12659424.

The Neuroprotective Mechanisms of PPAR-γ: Inhibition of Microglia-Mediated Neuroinflammation and Oxidative Stress in a Neonatal Mouse Model of Hypoxic-Ischemic White Matter Injury

BACKGROUND

Neuroinflammation and oxidative stress, mediated by microglial activation, hinder the development of oligodendrocytes (OLs) and delay myelination in preterm infants, leading to white matter injury (WMI) and long-term neurodevelopmental sequelae. Peroxisome proliferator-activated receptor gamma (PPAR-γ) has been reported to inhibit inflammation and oxidative stress via modulating microglial polarization in various central nervous system diseases. However, the relationship between PPAR-γ and microglial polarization in neonatal WMI is not well understood. Therefore, this study aimed to elucidate the role and mechanisms of PPAR-γ in preterm infants affected by WMI.

METHODS

In this study, an in vivo hypoxia-ischemia (HI) induced brain WMI neonatal mouse model was established. The mice were administered intraperitoneally with either RSGI or GW9662 to activate or inhibit PPAR-γ, respectively. Additionally, an in vitro oxygen-glucose deprivation (OGD) cell model was established and pretreated with pcDNA 3.1-PPAR-γ or si-PPAR-γ to overexpress or silence PPAR-γ, respectively. The neuroprotective effects of PPAR-γ were investigated in vivo. Firstly, open field test, novel object recognization test, and beam-walking test were employed to assess the effects of PPAR-γ on neurobehavioral recovery. Furthermore, assessment of OLs loss and OL-maturation disorder, the number of myelinated axons, myelin thickness, synaptic deficit, activation of microglia and astrocyte, and blood-brain barrier (BBB) were used to evaluate the effects of PPAR-γ on pathological repair. The mechanisms of PPAR-γ were explored both in vivo and in vitro. Assessment of microglia polarization, inflammatory mediators, reactive oxygen species (ROS), MDA, and antioxidant enzymes was used to evaluate the anti-inflammatory and antioxidative effects of PPAR-γ activation. An assessment of HMGB1/NF-κB and NRF2/KEAP1 signaling pathway was conducted to clarify the mechanisms by which PPAR-γ influences HI-induced WMI in neonatal mice.

RESULTS

Activation of PPAR-γ using RSGI significantly mitigated BBB disruption, promoted M2 polarization of microglia, inhibited activation of microglia and astrocytes, promoted OLs development, and enhanced myelination in HI-induced WMI. Conversely, inhibition of PPAR-γ using GW9662 further exacerbated the pathologic hallmark of WMI. Neurobehavioral tests revealed that neurological deficits were ameliorated by RSGI, while further aggravated by GW91662. In addition, activation of PPAR-γ significantly alleviated neuroinflammation and oxidative stress by suppressing HMGB1/NF-κB signaling pathway and activating NRF2 signaling pathway both in vivo and in vitro. Conversely, inhibition of PPAR-γ further exacerbated HI or OGD-induced neuroinflammation, oxidative stress via modulation of the same signaling pathway.

CONCLUSIONS

Our findings suggest that PPAR-γ regulates microglial activation/polarization as well as subsequent neuroinflammation/oxidative stress via the HMGB1/NF-κB and NRF2/KEAP1 signaling pathway, thereby contributing to neuroprotection and amelioration of HI-induced WMI in neonatal mice.

Association between SMOFlipid and impaired brain development on term-equivalent age brain magnetic resonance imaging in very preterm infants

Soybean oil, medium-chain triglycerides, olive oil, and fish oil (SMOFlipid) is used without evidence of benefits. We investigated the relationship between lipid emulsions and brain injury in term-equivalent age magnetic resonance imaging (MRI) in 148 very preterm infants with a birth weight of < 1500 g at ≤ 32 gestational weeks in a neonatal intensive care unit. Infants who received soybean-based lipid emulsions between January 2015 and December 2018 were compared with those who received SMOFlipids between January 2019 and December 2022. A negative binomial generalized linear model was applied for bivariate analysis. Modified log-Poisson regression with generalized linear models and a robust variance estimator (Huber-White) were applied to adjust for potential confounders. The Kidokoro score was used to determine if lipid emulsion type would affect brain morphology and growth at term-equivalent age. Eighty-six (58.9%) received SMOFlipid. SMOFlipid was associated with lower focal signal abnormality, myelination delay, increased extracerebral space, and cerebellar volume reduction (P = 0.02, P = 0.007, P = 0.01, P = 0.02, respectively). SMOFlipidis are associated with brain insult, especially in white matter, cortical gray matter, and the cerebellum. Well-designed studies are needed to investigate the effect of lipid emulsions on the central nervous system.

Assessment of neural function recovery in premature infants at high risk of brain injury using amplitude integrated electroencephalography and GMs scales

Preterm infants are a high-risk group for brain injury, and it is important to evaluate the neurological recovery of preterm infants. Therefore, this paper evaluates the neurological recovery in preterm infants at high risk of brain injury by amplitude-integrated EEG and GMs scale. The study collected basic information on preterm infants and performed amplitude integrated EEG examination and GMs scale evaluation. Amplitude integrated EEG examination attaches electrodes using multielectrode arrays onto specific areas of the premature head to record brain wave activity to monitor electrical activity in the preterm brain in real time and amplify and process through the signals received by the electrodes to obtain more detailed EEG data. The GMs scale evaluates the developmental and functional status of the child and allows an objective assessment of the development and recovery of neurological function by observing their performance in motor, language, cognition, and social interaction. Analysis of the data by statistical processing. The results showed that early brain injury was evident in high-risk infants. Amplitude integrated EEG parameters can have some predictive value for brain injury. There were also differences in GMs scale assessment between brain injury and non-brain injury. Amplitude integrated EEG combined with GMs scale has certain value in predicting brain injury and can provide an important basis for early intervention in children with preterm brain injury and help to improve their neurodevelopmental outcome.

Neurofilament light chain associates with IVH and ROP in extremely preterm infants

BACKGROUND

Neurofilament light chain (NfL) is known for indicating adult brain injury, but the role of NfL in extremely preterm infants is less studied. This study examines the relationship between NfL and neurovascular morbidities in these infants.

METHODS

A secondary analysis of the Mega Donna Mega trial was conducted on preterm infants <28 weeks gestational age (GA). The study measured NfL levels and proteomic profiles related to the blood-brain barrier in serum from birth to term-equivalent age, investigating the association of NfL with GA, retinopathy of prematurity (ROP), intraventricular hemorrhage (IVH), and blood-brain barrier proteins.

RESULTS

Higher NfL levels were seen in the first month in infants with severe IVH and for those born <25 weeks GA (independent of ROP or IVH). Additionally, infants born at 25-27 weeks GA with high NfL were at increased risk of developing severe ROP (independent of IVH). NfL was significantly associated with the proteins CDH5, ITGB1, and JAM-A during the first month.

CONCLUSION

NfL surges after birth in extremely preterm infants, particularly in those with severe IVH and ROP, and in the most immature infants regardless of IVH or ROP severity. These findings suggest NfL as a potential predictor of neonatal morbidities, warranting further validation studies.

IMPACT STATEMENT

This study shows that higher NfL levels are related to neurovascular morbidities in extremely preterm infants. The degree of immaturity seems important as infants born <25 weeks gestational age exhibited high postnatal serum NfL levels irrespective of neurovascular morbidities. Our findings suggest a potential link between NfL and neurovascular morbidities possibly affected by a more permeable blood-brain barrier.

Glymphatic System in Preterm Neonates: Developmental Insights Following Birth Asphyxia

BACKGROUND

Birth asphyxia (BA) and germinal matrix hemorrhage-intraventricular hemorrhage (GMH-IVH) are common clinical events in preterm neonates. However, their effects on the glymphatic system (GS) development in preterm neonates remain arcane.

PURPOSE

To evaluate the developmental trajectory of the GS, and to investigate the effects of BA and GMH-IVH on GS function in preterm neonates.

STUDY TYPE

Prospective.

POPULATION

Two independent datasets, prospectively acquired internal dataset (including 99 preterm neonates, 40 female, mean [standard deviation] gestational age (GA) at birth, 29.95 [2.63] weeks) and the developing Human Connectome Project (dHCP) dataset (including 81 preterm neonates, 29 female, median [interquartile range] GA at birth, 32.71 [4.28] weeks).

FIELD STRENGTH/SEQUENCE

3.0 T MRI and diffusion-weighted spin-echo planar imaging sequence.

ASSESSMENT

The diffusion-weighted images were preprocessed in volumetric space using the FMRIB Software Library and diffusion along the perivascular space (DTI-ALPS) index was accessed to evaluate GS function.

STATISTICAL TESTS

Two sample t tests, one-way analysis of variance followed by least-significant difference (LSD) post hoc analysis, chi-squared tests, and Pearson's correlation analysis. Significance level: P < 0.05.

RESULTS

In prospectively acquired internal dataset, preterm neonates with BA exhibited a significant lower DTI-ALPS index than those without BA (0.98 ± 0.08 vs. 1.08 ± 0.07, T = -5.89); however, GMH-IVH did not exert significant influences on the DTI-ALPS index (P = 0.83 and 0.27). The DTI-ALPS index increased significantly at postmenstrual age ranging from 25 to 34 weeks (r = 0.38) and then plateaued after 34 weeks (P = 0.35), which we also observed in the dHCP dataset.

DATA CONCLUSION

BA rather than GMH-IVH serves as the major influencing factor in the development of GS in preterm neonates. Moreover, as GS development follows a nonlinear trajectory, we recommend close monitoring of GS development in preterm neonates with a GA less than 34 weeks.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 2.

Change in Volumes and Location of Preterm White Matter Injury over a Period of 15 Years

OBJECTIVE

To evaluate whether white matter injury (WMI) volumes and spatial distribution, which are important predictors of neurodevelopmental outcomes in preterm infants, have changed over a period of 15 years.

STUDY DESIGN

Five hundred and twenty-eight infants born <32 weeks' gestational age from 2 sequential prospective cohorts (cohort 1: 2006 through 2012; cohort 2: 2014 through 2019) underwent early-life (median 32.7 weeks postmenstrual age) and/or term-equivalent-age MRI (median 40.7 weeks postmenstrual age). WMI were manually segmented for quantification of volumes. There were 152 infants with WMI with 74 infants in cohort 1 and 78 in cohort 2. Multivariable linear regression models examined change in WMI volume across cohorts while adjusting for clinical confounders. Lesion maps assessed change in WMI location across cohorts.

RESULTS

There was a decrease in WMI volume in cohort 2 compared with cohort 1 (β = -0.6, 95% CI [-0.8, -0.3], P < .001) with a shift from more central to posterior location of WMI. There was a decrease in clinical illness severity of infants across cohorts.

CONCLUSIONS

We found a decrease in WMI volume and shift to more posterior location in very preterm infants over a period of 15 years. This may potentially reflect more advanced maturation of white matter at the time of injury which may be related to changes in clinical practice over time.

Childhood Health and Educational outcomes afteR perinatal Brain injury (CHERuB): protocol for a population-matched cohort study

INTRODUCTION

Over 3000 infants suffer a brain injury around the time of birth every year in England. Although these injuries can have important implications for children and their families, our understanding of how these injuries affect children's lives is limited.

METHODS AND ANALYSIS

The aim of the CHERuB study (Childhood Health and Educational outcomes afteR perinatal Brain injury) is to investigate longitudinal childhood health and educational outcomes after perinatal brain injury through the creation of a population-matched cohort study. This study will use the Department of Health and Social Care definition of perinatal brain injury which includes infants with intracranial haemorrhage, preterm white matter injury, hypoxic ischaemic encephalopathy, perinatal stroke, central nervous system infections, seizures and kernicterus. All children born with a perinatal brain injury in England between 2008 and 2019 will be included (n=54 176) and two matched comparator groups of infants without brain injury will be created: a preterm control group identified from the National Neonatal Research Data Set and a term/late preterm control group identified using birth records. The national health, education and social care records of these infants will be linked to ascertain their longitudinal childhood outcomes between 2008 and 2023. This cohort will include approximately 170 000 children. The associations between perinatal brain injuries and survival without neurosensory impairment, neurodevelopmental impairments, chronic health conditions and mental health conditions throughout childhood will be examined using regression methods and time-to-event analyses.

ETHICS AND DISSEMINATION

This study has West London Research Ethics Committee and Confidential Advisory Group approval (20/LO/1023 and 22/CAG/0068 issued 20/10/2022). Findings will be published in open-access journals and publicised via the CHERuB study website, social media accounts and our charity partners.

Lactoferrin intake from maternal milk during the neonatal hospitalization and early brain development among preterm infants

BACKGROUND

Lactoferrin is an immuno-modulatory nutrient in human milk that may be neuroprotective.

METHODS

In 36 infants born <32 weeks' gestation, we sampled human milk at 14 and 28 days of chronologic age and measured lactoferrin by electrochemiluminescence multiplex immunoassay. Using 3T quantitative brain magnetic resonance imaging scans obtained at term equivalent, we estimated total and regional brain volumes. We compared outcomes between infants exposed to low (bottom tertile, range 0.06-0.13 mg/mL) vs. high (top tertile, range 0.22-0.35 mg/mL) lactoferrin using median regression in models adjusted for gestational age, birth weight z-score, sex, and postmenstrual age.

RESULTS

Compared to infants exposed to low lactoferrin, infants exposed to high lactoferrin had 43.9 cc (95% CI: 7.6, 80.4) larger total brain volume, 48.3 cc (95% CI: 12.1, 84.6) larger cortical gray matter, and 3.8 cc (95% CI: 0.7, 7.0) larger deep gray matter volume at term equivalent age. Other regional brain volumes were not statistically different between groups.

CONCLUSION

Higher lactoferrin exposure during the neonatal hospitalization was associated with larger total brain and gray matter volumes, suggesting that lactoferrin may have potential as a dietary supplement to enhance brain growth in the neonatal intensive care unit setting.

IMPACT

This study suggests that lactoferrin, a whey protein found in human milk, may be beneficial for preterm infant brain development, and therefore has potential as a dietary supplement in the neonatal intensive care unit setting.

Long-term outcomes of very low birth weight infants with intraventricular hemorrhage: a nationwide population study from 2011 to 2019

BACKGROUND

Advancements in neonatal care have increased preterm infant survival but paradoxically raised intraventricular hemorrhage (IVH) rates. This study explores IVH prevalence and long-term outcomes of very low birth weight (VLBW) infants in Korea over a decade.

METHODS

Using Korean National Health Insurance data (NHIS, 2010-2019), we identified 3372 VLBW infants with IVH among 4,129,808 live births. Health-related claims data, encompassing diagnostic codes, diagnostic test costs, and administered procedures were sourced from the NHIS database. The results of the developmental assessments  are categorized into four groups based on standard deviation (SD) scores. Neonatal characteristics and complications were compared among the groups. Logistic regression models were employed to identify significant changes in the incidence of complications and to calculate odds ratios with corresponding 95% confidence intervals for each risk factor associated with mortality and morbidity in IVH. Long-term growth and development were compared between the two groups (years 2010-2013 and 2014-2017).

RESULTS

IVH prevalence was 12% in VLBW and 16% in extremely low birth weight (ELBW) infants. Over the past decade, IVH rates increased significantly in ELBW infants (P = 0.0113), while mortality decreased (P = 0.0225). Major improvements in certain neurodevelopmental outcomes and reductions in early morbidities have been observed among VLBW infants with IVH. Ten percent of the population received surgical treatments such as external ventricular drainage (EVD) or a ventriculoperitoneal (VP) shunt, with the choice of treatment methods remaining consistent over time. The IVH with surgical intervention group exhibited higher incidences of delayed development, cerebral palsy, seizure disorder, and growth failure (height, weight, and head circumference) up to 72 months of age (P < 0.0001). Surgical treatments were also significantly associated with abnormal developmental screening test results.

CONCLUSIONS

The neurodevelopmental outcomes of infants with IVH, especially those subjected to surgical treatments, continue to be a matter of concern. It is imperative to prioritize specialized care for patients receiving surgical treatments and closely monitor their growth and development after discharge to improve developmental prognosis. Supplementary file2 (MP4 77987 kb).

Effect of Combining Intrauterine Cerebral Blood Flow Changes with Electrical Activity on Prognostic Evaluation of Brain Injury

OBJECTIVES

We sought to investigate the value of combining intrauterine cerebral blood flow changes with brain electrical activity examination in evaluating the prognosis of brain injury.

METHODS

A total of 90 preterm infants were enrolled and divided into 2 groups: the brain damaged preterm infants group (n = 55) and the nonbrain damaged preterm infants group (n = 35). The diagnostic efficacy of combining intrauterine cerebral blood flow changes with electroencephalogram (EEG) activity examination in predicting the prognosis of preterm infants with brain injury was evaluated using T-test. Pearson linear correlation was applied to analyze the relationship between fetal intrauterine cerebral blood flow changes combined with electrical activity examination and the prognosis of brain injury.

RESULTS

Significant differences were seen in pulse index, the ratio of peak systolic velocity to end diastolic velocity ratio, and other indexes between the 2 groups (P < 0.05). The combined approach of intrauterine cerebral blood flow changes with EEG activity examination demonstrated significantly higher values for area under the curve, sensitivity and negative predictive value compared to using intrauterine cerebral blood flow changes or EEG activity examination alone (P < 0.05). A positive correlation was found between fetal intrauterine cerebral blood flow and electrical activity examination (P < 0.05).

CONCLUSIONS

Combining the assessment of intrauterine cerebral blood flow changes with cerebral electrical activity examination proved beneficial in diagnosing the prognosis of brain injury and provided an important reference for early clinical intervention.

A Multiplanar Radiomics Model Based on Cranial Ultrasound to Predict the White Matter Injury in Premature Infants and an Analysis of its Correlation With Neurodevelopment

OBJECTIVES

To develop and evaluate a multiplanar radiomics model based on cranial ultrasound (CUS) to predict white matter injury (WMI) in premature infants and explore its correlation with neurodevelopment.

METHODS

We retrospectively reviewed 267 premature infants. The radiomics features were extracted from five standard sections of CUS. The Spearman's correlation coefficient combined with the least absolute shrinkage and selection operator (LASSO) was applied to select features and build radiomics signature, and a multiplanar radiomics model was constructed based on the radiomics signature of five planes. The performance of the model was evaluated using the area under the receiver operating characteristic curve (AUC). Infants with WMI were re-examined by ultrasound at 2 and 4 weeks after birth, and the recovery degree of WMI was evaluated using multiplanar radiomics. The relationship between WMI and the recovery degree and neurodevelopment was analyzed.

RESULTS

The AUC of the multiplanar radiomics in the training and validation sets were 0.94 and 0.91, respectively. The neurodevelopmental function scores in infants with WMI were significantly lower than those in healthy preterm infants and full-term newborns (P < .001). There were statistically significant differences in the neurodevelopmental function scores of infants between the 2- and 4-week lesion disappearance and 4-week lesion persistence (P < .001).

CONCLUSIONS

The multiplanar radiomics model showed a good performance in predicting the WMI of premature infants. It can not only provide objective and accurate results but also dynamically monitor the degree of recovery of WMI to predict the prognosis of premature infants.

Preterm birth: A neuroinflammatory origin for metabolic diseases?

Preterm birth and its related complications have become more and more common as neonatal medicine advances. The concept of "developmental origins of health and disease" has raised awareness of adverse perinatal events in the development of diseases later in life. To explore this concept, we propose that encephalopathy of prematurity (EoP) as a potential pro-inflammatory early life event becomes a novel risk factor for metabolic diseases in children/adolescents and adulthood. Here, we review epidemiological evidence that links preterm birth to metabolic diseases and discuss possible synergic roles of preterm birth and neuroinflammation from EoP in the development of metabolic diseases. In addition, we explore theoretical underlying mechanisms regarding developmental programming of the energy control system and HPA axis.

Size and Location of Preterm Brain Injury and Associations With Neurodevelopmental Outcomes

BACKGROUND AND OBJECTIVES

We examined associations of white matter injury (WMI) and periventricular hemorrhagic infarction (PVHI) volume and location with 18-month neurodevelopment in very preterm infants.

METHODS

A total of 254 infants born <32 weeks' gestational age were prospectively recruited across 3 tertiary neonatal intensive care units (NICUs). Infants underwent early-life (median 33.1 weeks) and/or term-equivalent-age (median 41.9 weeks) MRI. WMI and PVHI were manually segmented for quantification in 92 infants. Highest maternal education level was included as a marker of socioeconomic status and was defined as group 1 = primary/secondary school; group 2 = undergraduate degree; and group 3 = postgraduate degree. Eighteen-month neurodevelopmental assessments were completed with Bayley Scales of Infant and Toddler Development, Third Edition. Adverse outcomes were defined as a score of less than 85 points. Multivariable linear regression models were used to examine associations of brain injury (WMI and PVHI) volume with neurodevelopmental outcomes. Voxel-wise lesion symptom maps were developed to assess relationships between brain injury location and neurodevelopmental outcomes.

RESULTS

Greater brain injury volume was associated with lower 18-month Motor scores (β = -5.7, 95% CI -9.2 to -2.2, p = 0.002) while higher maternal education level was significantly associated with higher Cognitive scores (group 3 compared 1: β = 14.5, 95% CI -2.1 to 26.9, p = 0.03). In voxel-wise lesion symptom maps, brain injury involving the central and parietal white matter was associated with an increased risk of poorer motor outcomes.

DISCUSSION

We found that brain injury volume and location were significant predictors of motor, but not cognitive outcomes, suggesting that different pathways may mediate outcomes across domains of neurodevelopment in preterm infants. Specifically, assessing lesion size and location may allow for more accurate identification of infants with brain injury at highest risk of poorer motor outcomes. These data also highlight the importance of socioeconomic status in cognitive outcomes, even in preterm infants with brain injury.

Neuroimaging to guide neuroprognostication in the neonatal intensive care unit

PURPOSE OF REVIEW

Neurological problems are common in infants admitted to the neonatal intensive care unit (NICU). Various neuroimaging modalities are available for neonatal brain imaging and are selected based on presenting problem, timing and patient stability.

RECENT FINDINGS

Neuroimaging findings, taken together with clinical factors and serial neurological examination can be used to predict future neurodevelopmental outcomes. In this narrative review, we discuss neonatal neuroimaging modalities, and how these can be optimally utilized to assess infants in the NICU. We will review common patterns of brain injury and neurodevelopmental outcomes in hypoxic-ischemic encephalopathy, perinatal arterial ischemic stroke and preterm brain injury.

SUMMARY

Timely and accurate neuroprognostication can identify infants at risk for neurodevelopmental impairment and allow for early intervention and targeted therapies to improve outcomes.

Childhood outcomes after low-grade intraventricular haemorrhage: A systematic review and meta-analysis

AIM

To undertake a systematic review and meta-analysis exploring school-age neurodevelopmental outcomes of children after low-grade intraventricular haemorrhage (IVH).

METHOD

The published and grey literature was extensively searched to identify observational comparative studies exploring neurodevelopmental outcomes after IVH grades 1 and 2. Our primary outcome was neurodevelopmental impairment after 5 years of age, which included cognitive, motor, speech and language, behavioural, hearing, or visual impairments.

RESULTS

This review included 12 studies and over 2036 infants born preterm with low grade IVH. Studies used 30 different neurodevelopmental tools to determine outcomes. There was conflicting evidence of the composite risk of neurodevelopmental impairment after low-grade IVH. There was evidence of an association between low-grade IVH and lower IQ at school age (-4.23, 95% confidence interval [CI] -7.53, -0.92, I2  = 0%) but impact on school performance was unclear. Studies reported an increased crude risk of cerebral palsy after low-grade IVH (odds ratio [OR] 2.92, 95% CI 1.95, 4.37, I2  = 41%). No increased risk of speech and language impairment or behavioural impairment was found. Few studies addressed hearing and visual impairment.

INTERPRETATION

This systematic review presents evidence that low-grade IVH is associated with specific neurodevelopmental impairments at school age, lending support to the theory that low-grade IVH is not a benign condition.

WHAT THIS PAPER ADDS

The functional impact of low-grade intraventricular haemorrhage (IVH) at school age is unknown. Low-grade IVH is associated with a lower IQ at school age. The risk of cerebral palsy is increased after low-grade IVH. Low-grade IVH is not associated with speech and language impairment.

Early IGF-1 receptor inhibition in mice mimics preterm human brain disorders and reveals a therapeutic target

Besides recent advances in neonatal care, preterm newborns still develop sex-biased behavioral alterations. Preterms fail to receive placental insulin-like growth factor-1 (IGF-1), a major fetal growth hormone in utero, and low IGF-1 serum levels correlate with preterm poor neurodevelopmental outcomes. Here, we mimicked IGF-1 deficiency of preterm newborns in mice by perinatal administration of an IGF-1 receptor antagonist. This resulted in sex-biased brain microstructural, functional, and behavioral alterations, resembling those of ex-preterm children, which we characterized performing parallel mouse/human behavioral tests. Pharmacological enhancement of GABAergic tonic inhibition by the U.S. Food and Drug Administration-approved drug ganaxolone rescued functional/behavioral alterations in mice. Establishing an unprecedented mouse model of prematurity, our work dissects the mechanisms at the core of abnormal behaviors and identifies a readily translatable therapeutic strategy for preterm brain disorders.

Developing a practical neurodevelopmental prediction model for targeting high-risk very preterm infants during visit after NICU: a retrospective national longitudinal cohort study

BACKGROUND

Follow-up visits for very preterm infants (VPI) after hospital discharge is crucial for their neurodevelopmental trajectories, but ensuring their attendance before 12 months corrected age (CA) remains a challenge. Current prediction models focus on future outcomes at discharge, but post-discharge data may enhance predictions of neurodevelopmental trajectories due to brain plasticity. Few studies in this field have utilized machine learning models to achieve this potential benefit with transparency, explainability, and transportability.

METHODS

We developed four prediction models for cognitive or motor function at 24 months CA separately at each follow-up visits, two for the 6-month and two for the 12-month CA visits, using hospitalized and follow-up data of VPI from the Taiwan Premature Infant Follow-up Network from 2010 to 2017. Regression models were employed at 6 months CA, defined as a decline in The Bayley Scales of Infant Development 3rd edition (BSIDIII) composite score > 1 SD between 6- and 24-month CA. The delay models were developed at 12 months CA, defined as a BSIDIII composite score < 85 at 24 months CA. We used an evolutionary-derived machine learning method (EL-NDI) to develop models and compared them to those built by lasso regression, random forest, and support vector machine.

RESULTS

One thousand two hundred forty-four VPI were in the developmental set and the two validation cohorts had 763 and 1347 VPI, respectively. EL-NDI used only 4-10 variables, while the others required 29 or more variables to achieve similar performance. For models at 6 months CA, the area under the receiver operating curve (AUC) of EL-NDI were 0.76-0.81(95% CI, 0.73-0.83) for cognitive regress with 4 variables and 0.79-0.83 (95% CI, 0.76-0.86) for motor regress with 4 variables. For models at 12 months CA, the AUC of EL-NDI were 0.75-0.78 (95% CI, 0.72-0.82) for cognitive delay with 10 variables and 0.73-0.82 (95% CI, 0.72-0.85) for motor delay with 4 variables.

CONCLUSIONS

Our EL-NDI demonstrated good performance using simpler, transparent, explainable models for clinical purpose. Implementing these models for VPI during follow-up visits may facilitate more informed discussions between parents and physicians and identify high-risk infants more effectively for early intervention.

White Matter Injury on Early-versus-Term-Equivalent Age Brain MRI in Infants Born Preterm

BACKGROUND AND PURPOSE

White matter injury in infants born preterm is associated with adverse neurodevelopmental outcomes, depending on the extent and location. White matter injury can be visualized with MR imaging in the initial weeks following preterm birth but is more commonly defined at term-equivalent-age MR imaging. Our aim was to see how white matter injury detection in MR imaging compares between the 2 time points.

MATERIALS AND METHODS

This study compared white matter injury on early brain MR imaging (30-34 weeks' postmenstrual age) with white matter injury assessment at term-equivalent (37-42 weeks) MR imaging, using 2 previously published and standardized scoring systems, in a cohort of 30 preterm infants born at <33 weeks' gestational age.

RESULTS

There was a strong association between the systematic assessments of white matter injury at the 2 time points (P = .007) and the global injury severity (P < .001).

CONCLUSIONS

Although the optimal timing to undertake neuroimaging in the preterm infant remains to be determined, both early (30-34 weeks) and term-equivalent MR imaging provide valuable information on white matter injury and the risk of associated sequelae.

Optimizing trajectories of social adaptive competencies after extreme prematurity during the first 1000 days

Over 75% of surviving extremely preterm infants do not have major neurodevelopmental disabilities; however, more than half face difficulties with communication, coordination, attention, learning, social, and executive function abilities. These "minor" challenges can have a negative impact on educational and social outcomes, resulting in physical, behavioral, and social health problems in adulthood. We will review assessment tools for social-emotional and adaptive functional skills in early childhood as these determine family and early childhood supports. We highlight bronchopulmonary dysplasia as an example of the critical intersections of parental wellbeing, medical and developmental adaptive trajectories in infancy and early childhood, and partnerships between child neurologists and community medical and developmental professionals. We examine studies of engaging parents to promote developmental trajectories, with a focus on supporting parent-child interactions that underlie communication, social-adaptive behaviors, and learning in the first 1000 days of life. Recommendations for neurodevelopmental surveillance and screening of extremely preterm infants can also be applied to infants with other risk factors for altered neurodevelopment.

Neurodevelopmental outcomes in preterm or low birth weight infants with germinal matrix-intraventricular hemorrhage: a meta-analysis

BACKGROUND

This meta-analysis aimed to identify the near- and long-term neurodevelopmental prognoses of preterm or low birth weight (LBW) infants with different severities of intraventricular hemorrhage (IVH).

METHODS

Four databases were searched for observational studies that were qualified using the Newcastle-Ottawa Scale.

RESULTS

37 studies involving 32,370 children were included. Compared to children without IVH, children with mild IVH had higher incidences of neurodevelopmental impairment (NDI), cerebral palsy (CP), motor/cognitive delay, hearing impairment and visual impairment, as well as lower scores of the mental development index (MDI) and psychomotor development (PDI). Moreover, compared to mild IVH, severe IVH increased susceptibilities of children to NDI, motor delay, CP, hearing impairment and visual impairment, with worse performances in MDI, PDI, motor score and IQ. Mild IVH was not associated with seizures or epilepsy.

CONCLUSIONS

Adverse neurodevelopmental outcomes positively associated with the occurrence and severity of IVH in preterm or LBW infants, providing evidence for counseling and further decisions regarding early therapeutic interventions.

IMPACT

Adverse neurodevelopmental outcomes later in life were closely associated with the occurrence and severity of IVH in preterm or LBW infants. Our results highlight the importance to make prediction of the neurodevelopmental outcomes of children born preterm or LBW with a history of IVH, which will guide affected parents when their children need clinical interventions to reach the full potential. We emphasize the importance of identifying specific developmental delays that may exist in children with IVH, providing detailed information for the development of comprehensive intervention measures.

Fate of melatonin orally administered in preterm newborns: Antioxidant performance and basis for neuroprotection

Preterm infants cannot counteract excessive reactive oxygen species (ROS) production due to preterm birth, leading to an excess of lipid peroxidation with malondialdehyde (MDA) production, capable of contributing to brain damage. Melatonin (ME), an endogenous brain hormone, and its metabolites, act as a free radical scavenger against ROS. Unfortunately, preterms have an impaired antioxidant system, resulting in the inability to produce and release ME. This prospective, multicenter, parallel groups, randomized, double-blind, placebo-controlled trial aimed to assess: (i) the endogenous production of ME in very preterm infants (gestational age ≤ 29 + 6 WE, 28 infants in the ME and 26 in the placebo group); (ii) the exogenous hormone availability and its metabolization to the main metabolite, 6-OH-ME after 15 days of ME oral treatment; (iii) difference of MDA plasma concentration, as peroxidation marker, after treatment. Blood was collected before the first administration (T1) and after 15 days of administration (T2). ME and 6-OH-ME were detected by liquid chromatography tandem mass spectrometry, MDA was measured by liquid chromatograph with fluorescence detection. ME and 6-OH-ME were not detectable in the placebo group at any study time-point. ME was absent in the active group at T1. In contrast, after oral administration, ME and 6-OH-ME resulted highly detectable and the difference between concentrations T2 versus T1 was statistically significant, as well as the difference between treated and placebo groups at T2. MDA levels seemed stable during the 15 days of treatment in both groups. Nevertheless, a trend in the percentage of neonates with reduced MDA concentration at T2/T1 was 48.1% in the ME group versus 38.5% in the placebo group. We demonstrated that very preterm infants are not able to produce endogenous detectable plasma levels of ME during their first days of life. Still, following ME oral administration, appreciable amounts of ME and 6-OH-ME were available. The trend of MDA reduction in the active group requires further clinical trials to fix the dosage, the length of ME therapy and to identify more appropriate indexes to demonstrate, at biological and clinical levels, the antioxidant activity and consequent neuroprotectant potential of ME in very preterm newborns.

Treatment of preterm brain injury via gut-microbiota-metabolite-brain axis

BACKGROUND

Brain injury in preterm infants potentially disrupts critical structural and functional connective networks in the brain. It is a major cause of neurological sequelae and developmental deficits in preterm infants. Interesting findings suggest that the gut microbiota (GM) and their metabolites contribute to the programming of the central nervous system (CNS) during developmental stages and may exert structural and functional effects throughout the lifespan.

AIM

To summarize the existing knowledge of the potential mechanisms related to immune, endocrine, neural, and blood-brain barrier (BBB) mediated by GM and its metabolites in neural development and function.

METHODS

We review the recent literature and included 150 articles to summarize the mechanisms through which GM and their metabolites work on the nervous system. Potential health benefits and challenges of relevant treatments are also discussed.

RESULTS

This review discusses the direct and indirect ways through which the GM may act on the nervous system. Treatment of preterm brain injury with GM or related derivatives, including probiotics, prebiotics, synbiotics, dietary interventions, and fecal transplants are also included.

CONCLUSION

This review summarizes mechanisms underlying microbiota-gut-brain axis and novel therapeutic opportunities for neurological sequelae in preterm infants. Optimizing the initial colonization and microbiota development in preterm infants may represent a novel therapy to promote brain development and reduce long-term sequelae.

Intervention Bundle for Optimization of Procedural Sedation for Newborns Undergoing Magnetic Resonance Imaging: A Single-Center Quality Improvement Project in Qatar

Introduction

Magnetic resonance imaging (MRI) is a common procedure in tertiary care neonatal intensive care units (NICUs). MRIs aid in detailing structural anatomy and are increasingly utilized for prognostication. Keeping babies calm and motion-free in the MRI suite is challenging, and various approaches have been adopted to obtain the best image quality. We share our experience of intervention bundle for procedural sedation with the novel use of buccal midazolam in our NICU for babies undergoing MRI.

Methods

This single-center quality improvement project comprised two epochs. Epoch 1 from April 2018 to December 2020 provided baseline data regarding sedation use and helped identify causes for suboptimal images and the adverse event rate. Following the implementation of an interventional bundle comprising specific midazolam dose recommendations tailored to background risk factors and streamlining the procedural sedation process, similar comparative data were collected in epoch 2 (May 2021 to December 2022) after a washout period.

Results

Of 424 patients, 238 and 108 had MRI done under either procedural sedation protocol or feed and wrap technique in epoch 1 and 2, respectively. After excluding babies whose MRIs were performed under sedative infusions, 30 (13%) babies had adverse events in epoch 1, while only 8 (7%) events occurred in epoch 2. There was also a 37% improvement in the documentation of procedural sedation between the two epochs.

Conclusion

Procedural sedation with buccal midazolam under neonatologist supervision is safe, efficient, and effective in babies undergoing MRI in this single-center study. More extensive studies may be warranted to assess the suitability of this sedation modality for broader use.

Risk factors for brain injury in premature infants with twin-to-twin transfusion syndrome: a retrospective cohort study

Background

Brain injury (BI) is prevalent in premature infants with twin-to-twin transfusion syndrome (TTTS), while risk factors of BI in these patients remains unknown. Our study aims to discern potential risk factors that contribute to BI in premature infants with TTTS.

Methods

We conducted a retrospective cohort and analyzed clinical data of premature infants diagnosed with TTTS at the Northwest Women's and Children's Hospital between January 1, 2015 and January 1, 2020. Data included the infants' perinatal information, key postnatal examinations, laboratory tests, and treatments.

Results

Of the 84 patients enrolled in the study, 22 (26.2%) were categorized in the BI group and 62 (73.8%) in the non-BI group, based on cranial imaging. No significant differences were found at baseline between the groups in relation to the proportion of males (40.9% vs. 35.5%, P=0.845), median gestational age (weeks) [31.9 (31.5, 33.4) vs. 34.2 (31.6, 35.4), P=0.061], average weight (g) (1,676.4±567.5 vs. 1,845.2±511.7, P=0.200), maternal age (years) [29.5 (26.0, 31.0) vs. 28.5 (27.8, 31.0), P=0.656], the proportion of in-vitro fertilization (9.1% vs. 16.1%, P=0.648), cesarean sections (86.4% vs. 93.5%, P=0.549) or TTTS donor infants (50.0% vs. 51.6%, P=0.897). Multivariate logistic regression analysis indicated that invasive mechanical ventilation [invasive mechanical ventilation (IMV); odds ratio (OR) =4.365; 95% confidence interval (CI): 1.066-17.870; P=0.040], [necrotizing enterocolitis (NEC); OR =8.632; 95% CI: 1.542-48.318; P=0.014], [single intrauterine fetal demise (sIUFD); OR =14.067; 95% CI: 1.298-224.421; P=0.031], and a 5-minute Apgar score <9 (OR =4.663; 95% CI: 1.015-21.419; P=0.048) were strongly associated with BI in TTTS premature infants.

Conclusions

Our study identifies IMV, NEC, sIUFD, and a 5-minute Apgar score <9 as independent risk factors for BI in premature infants with TTTS.

Mask ventilation using volume-targeted neonatal ventilator for neonatal resuscitation: a randomised cross-over simulation study

OBJECTIVE

To use simulations to compare a novel mask ventilation method using a neonatal ventilator, with mask ventilation using a T-piece resuscitator, to study human factors prior to clinical testing.

DESIGN

Prospective randomised cross-over simulation study. Participants were briefly trained to use a neonatal ventilator for mask ventilation. Each participant was fitted with eye-tracking glasses to record visual attention (VA) and performed two simulated preterm neonatal resuscitations in a randomised sequence.

SETTING

In situ in a neonatal resuscitation room within a Level 3 neonatal intensive care unit.

PARTICIPANTS

Healthcare professionals (HCPs) trained in neonatal resuscitation with experience as team leaders.

INTERVENTIONS

Semiautomated, ventilator-based, volume-targeted positive pressure mask ventilation (VTV-PPV) versus manual mask ventilation via T-piece device (T-piece PPV).

MAIN OUTCOME MEASURES

Subjective workload (Surgical Task Load Index, SURG-TLX), VA, quantitative and qualitative postsimulation survey responses.

RESULTS

Thirty HCPs participated. HCPs reported higher total SURG-TLX scores (43.5/120 vs 33.8/120) and higher scores in mental demand (8.2/20 vs 5.6/20), physical demand (6.6/20 vs 5.1/20), task complexity (8.2/20 vs 6/20) and situational stress (8.3/20 vs 5.9/20) for VTV-PPV. Temporal demand and distraction scores were similar. While participants took longer to complete VTV-PPV simulations, participants dedicated similar a %VA to the mannikin and T-piece gauges or ventilator screen. More participants increased the rate of ventilation during VTV-PPV; other corrective steps were similar. Overall, participants rated VTV-PPV positively. Participants identified potential challenges with physical ergonomics, cognition and teamwork.

CONCLUSION

Using a neonatal ventilator to perform volume-targeted PPV is feasible, but human factors need to be considered.

Inhibition of the proteoglycan receptor PTPσ promotes functional recovery on a rodent model of preterm hypoxic-ischemic brain injury

BACKGROUND

Preterm white matter injury (WMI) is the most common brain injury in preterm infants and is associated with long-term adverse neurodevelopmental outcomes. Protein tyrosine phosphatase sigma (PTPσ) was discovered as chondroitin sulfate proteoglycan (CSPG) receptor that played roles in inhibiting myelin regeneration in spinal injury, experimental autoimmune encephalomyelitis, and stroke models. However, the role of PTPσ in perinatal WMI is not well understood.

AIMS

This study examines the effect of PTPσ inhibition on neurodevelopmental outcomes, myelination, and neuroinflammation in a mouse model of preterm WMI.

MATERIALS AND METHODS

Modified Rice-Vannucci model was performed on postnatal day 3 (P3) C57BL/6 mice. Intracellular Sigma Peptide (ISP) or vehicle was administrated subcutaneously one hour after injury for an additional 14 consecutive days. A battery of behavioral tests was performed to evaluate the short- and long-term effects of ISP on neurobehavioral deficit. Real time qPCR, western blot, immunofluorescence, and transmission electron microscopy were performed to assess white matter development. qPCR and flow cytometry were performed to evaluate neuroinflammation and microglia/macrophage phenotype.

RESULTS

The expression of PTPσ was increased after preterm WMI. ISP improved short-term neurological outcomes and ameliorated long-term motor and cognitive function of mice after preterm WMI. ISP promoted oligodendrocyte differentiation, maturation, myelination, and improved microstructure of myelin after preterm WMI. Furthermore, ISP administration fostered a beneficial inflammatory response in the acute phase after preterm WMI, inhibited the infiltration of peripheral macrophages, and promoted anti-inflammatory phenotype of microglia/macrophages.

CONCLUSION

PTPσ inhibition can ameliorate neurofunctional deficit, promote white matter development, modulate neuroinflammation and microglia/macrophage phenotype after preterm WMI. Thus, ISP administration may be a potential therapeutic strategy to improve neurodevelopmental outcomes of perinatal WMI.

Preterm birth and early life environmental factors: neuropsychological profiles at adolescence and young adulthood

OBJECTIVES

To establish neuropsychological profiles after high- and low-risk preterm birth (i.e., with and without neonatal brain injury) during adolescence and young adulthood and to assess the potential role of early life environmental factors in cognition.

STUDY DESIGN

Participants (N = 177; Mage = 20.11 years) of both sexes were evaluated when adolescent or in young adulthood. They were grouped according to their birth status: 30 high-risk preterm, 83 low-risk preterm and 64 born at full term.

RESULTS

Significant differences were found in several cognitive domains between groups. Furthermore, familial socioeconomic status (SES) moderated the relation between the degree of maturity/immaturity at birth and cognition (F(5,171) = 11.94, p < 0.001, R2 = 0.26).

DISCUSSION

The findings showed different neuropsychological profiles during adolescence and young adulthood, with the high-risk preterm sample evidencing lower cognitive values. In addition, higher scores in the familial SES score in this study seem to have a protective effect on cognition.

Late preterm and very preterm infants differ in the acquisition time and quantity of reaches with grasping at reaching onset: an exploratory study

Introduction

The onset of manual reaching allows the expansion of the infant's interaction with the environment. When born preterm, infants become vulnerable to problems in the development of reaching. However, it is still unknown whether there are differences in reaching according to the degree of prematurity.

Objective

This study aimed to explore the differences in reaching acquisition and behavior between late preterm and very preterm infants, as well as whether age and clinical variables influence the results.

Method

This is an exploratory, comparative, observational study. In total, 24 infants were included soon after reaching onset; 12 infants were born late preterm (35.55 ± 0.67 gestational weeks) and 12 very preterm (30.60 ± 0.05 gestational weeks). Infants were placed in a baby seat, and a toy was placed at a reachable distance for 2 min. Reaching behavior was the primary variable; birth weight and length of hospital stay were secondary variables.

Results

The age of reaching onset was higher in the very preterm group. The proportion of reaches with grasping was higher in the late preterm group. These differences were affected by the lower birth weight and longer length of hospital stay in the very preterm group. The proportions of proximal and distal adjustments did not differ between groups.

Conclusion

Very preterm infants presented disadvantages in the acquisition time and the number of reaches with grasping, but not in the proportions of proximal and distal adjustments of reaching, relative to late preterm infants. Group differences were influenced by clinical variables.

School-age outcomes of children after perinatal brain injury: a systematic review and meta-analysis

BACKGROUND

Over 3000 children suffer a perinatal brain injury in England every year according to national surveillance. The childhood outcomes of infants with perinatal brain injury are however unknown.

METHODS

A systematic review and meta-analyses were undertaken of studies published between 2000 and September 2021 exploring school-aged neurodevelopmental outcomes of children after perinatal brain injury compared with those without perinatal brain injury. The primary outcome was neurodevelopmental impairment, which included cognitive, motor, speech and language, behavioural, hearing or visual impairment after 5 years of age.

RESULTS

This review included 42 studies. Preterm infants with intraventricular haemorrhage (IVH) grades 3-4 were found to have a threefold greater risk of moderate-to-severe neurodevelopmental impairment at school age OR 3.69 (95% CI 1.7 to 7.98) compared with preterm infants without IVH. Infants with perinatal stroke had an increased incidence of hemiplegia 61% (95% CI 39.2% to 82.9%) and an increased risk of cognitive impairment (difference in full scale IQ -24.2 (95% CI -30.73 to -17.67) . Perinatal stroke was also associated with poorer academic performance; and lower mean receptive -20.88 (95% CI -36.66 to -5.11) and expressive language scores -20.25 (95% CI -34.36 to -6.13) on the Clinical Evaluation of Language Fundamentals (CELF) assessment. Studies reported an increased risk of persisting neurodevelopmental impairment at school age after neonatal meningitis. Cognitive impairment and special educational needs were highlighted after moderate-to-severe hypoxic-ischaemic encephalopathy. However, there were limited comparative studies providing school-aged outcome data across neurodevelopmental domains and few provided adjusted data. Findings were further limited by the heterogeneity of studies.

CONCLUSIONS

Longitudinal population studies exploring childhood outcomes after perinatal brain injury are urgently needed to better enable clinicians to prepare affected families, and to facilitate targeted developmental support to help affected children reach their full potential.

Decision-making for extremely preterm infants with severe hemorrhages on head ultrasound: Science, values, and communication skills

Severe intracranial hemorrhages are not rare in extremely preterm infants. They occur early, generally when babies require life-sustaining interventions. This may lead to ethical discussions and decision-making about levels of care. Prognosis is variable and depends on the extent, location, and laterality of the lesions, and, importantly also on the subsequent occurrence of other clinical complications or progressive ventricular dilatation. Decision-making should depend on prognosis and parental values. This article will review prognosis and the uncertainty of outcomes for different lesions and provide an outline of ways to conduct an ethically appropriate discussion on the decision of whether to continue life sustaining therapy. It is possible to communicate in a compassionate and honest way with parents and engage in decision-making, focussing on personalized information and decisions, and on function, as opposed to diagnosis.

Neuroimaging of Germinal Matrix and Intraventricular Hemorrhage in Premature Infants

Germinal matrix and intraventricular hemorrhage (GM-IVH) are the major causes of intracranial hemorrhage in premature infants. Cranial ultrasound (cUS) is the imaging modality of choice for diagnosing and classifying GM-IVH. Magnetic resonance imaging (MRI), usually performed at term-equivalent age, is more sensitive than cUS in identifying hemorrhage in the brain. Post-hemorrhagic ventricular dilatation is a significant complication of GM-IVH and correlates with adverse neurodevelopmental outcomes. In this review, we discuss the various imaging findings of GM-IVH in premature infants, focusing on the role of cUS and MRI.

Association between the General Movement Optimality Score and clinical features in newborns during hospitalization: A cross-sectional study

AIMS

To describe the General Movements (GMs) of hospitalized newborns to verify if their global and detailed GMA are related and if their GMs are associated with clinical features.

METHODS

Cross-sectional study. Thirty-eight preterm and full-term newborns, who were hospitalized in the neonatal intermediate care unit of a reference hospital, were included. Prechtl's General Movement Assessment (GMA), including the General Movement Optimality Score (GMOS) list, was used as an assessment tool. Clinical variables, such as preterm birth, birthweight, length of hospitalization, Apgar scores, pregnancy problems, admission at neonatal intensive care unit, use of invasive mechanical ventilation, and brain imaging findings were also collected. Newborns were videoed at a single time for 3 min before discharge.

RESULTS

Most newborns presented GMs with normal or poor repertoire quality. GMOS ranged from 17 to 42 points. Scores were lower in abnormal GMs. Abnormal GMs were associated with preterm birth, length of hospital stay >30 days and birthweight <2500 g. Accordingly, lower GMOSs were also associated with preterm birth, a birthweight <2500 g and a hospital stay >30 days but also with the invasive mechanical ventilation application.

CONCLUSION

Preterm and full-term newborns presented normal or abnormal GMs during hospitalization. Preterm birth, low birthweight, longer hospital stay and a time period of invasive ventilation were associated with worse GM behaviors.