Consensus Approach for Standardizing the Screening and Classification of Preterm Brain Injury Diagnosed With Cranial Ultrasound: A Canadian Perspective

The value of magnetic resonance imaging in congenital cytomegalovirus infection: a systematic review

Congenital cytomegalovirus (cCMV) infection can lead to severe neurodevelopmental and hearing impairments. Imaging techniques can be used both pre- and postnatally to assess early signs of infection. The objective was to provide a systematic review of current literature regarding magnetic resonance imaging (MRI) and its value to predict clinical outcome in children with cCMV. PubMed, Embase, and Web of Science were searched for studies investigating MRI in cCMV between 2016-2024. Risk of bias was assessed using Newcastle-Ottawa quality assessment scales. Descriptive synthesis was performed. Twenty studies were included. MRI detected brain abnormalities in 5.0-53.0% of infected patients prenatally and 26.9-69.0% postnatally. The three most frequently detected abnormalities included white matter lesions, subependymal cysts, and ventricular dilatation. Symptoms at birth, first trimester seroconversion, and high viral load were associated with abnormal MRI; however, brain abnormalities were still found in 33-37% of clinically asymptomatic patients. Prenatal MRI had a negative predictive value of 94-100% and a positive predictive value of 12-60% for predicting adverse clinical outcome. Five in six studies found an association between MRI abnormalities and neurodevelopmental impairments, five in eight with (congenital) hearing loss. MRI detected additional abnormalities in 5.6-19.4% of children with normal ultrasound. In conclusion, MRI can detect a wide range of brain abnormalities, both pre- and postnatally, in symptomatic and asymptomatic patients. MRI can be a helpful tool in the prediction of clinical impairments and seems complementary to ultrasound. Therefore, both fetal and neonatal MRI should be considered in the standard work-up of all cCMV-infected children.

Visual pathways functioning in healthy pre-term adolescents: Sex but not gestational age effect

BACKGROUND

Visuo-spatial and visuo-perceptual functioning is widely studied in preterm child and is strongly sex-specific. However, little to no data is available regarding male-female differences in preterm children and adolescents and about the interaction effect between sex and preterm birth.

METHODS

We studied 30 adolescents born preterm with normal cognitive and clinical neurological outcomes and 34 age-matched controls to investigate the interaction between levels of prematurity and sex in predicting the outcome of visual pathways functioning and to explore the relation between psychophysiological perceptive processing and neuropsychological performance.

RESULTS

In the presence of prematurity, a greater female vulnerability in central visuo-cognitive processing (Form Coherence Task), but not in neuropsychological accuracy (Street Completion Test and Visual Object and Space Perception battery), seems to be more evident. Moreover, the psychophysical threshold is correlated to neuropsychological accuracy only in preterm females and not in males.

CONCLUSION

These results support the idea that the male vulnerability in cognitive functioning described in prematurity-related developmental conditions is negligible during school age in children-adolescents with normal cognitive and clinical neurological outcomes.

IMPACT

Visuo-perceptual functioning is widely studied in prematurity. However, few data are available about the interaction effect between sex and preterm birth in predicting visuo-perceptual functioning. We evidenced that in females born preterm with preserved cognitive abilities, the efficiency of the psychophysical visuo-perceptual threshold is reduced, but not related to the neuropsychological performance. Females may implement compensation strategies to achieve good performance regardless of the perceptual threshold. The present study addresses an important gap in literature, suggesting possible sex-specific outcomes in visuo-perceptual ability among preterm children and adolescents with normal intelligence and neurological outcomes.

Nomograms and Reference Ranges for Intra-Cranial Ventricular Dimensions in Indian Neonates

OBJECTIVES

To establish normal reference values for commonly used ventricular indices - Anterior Horn Width (AHW), Ventricular Index (VI) and Thalamo-Occipital Distance (TOD)-against common variables including gestational age, birth weight and head circumference in Indian newborns.

METHODS

This was a cross-sectional study. Cranial ultrasound was performed between post-natal days 3 to 7. Anterior fontanelle was taken as the acoustic window. Data were analyzed to determine correlation, coefficient of determination (R2), regression equations and plotted against gestational age (GA).

RESULTS

Total 2200 newborns were included in the study. The study observed that there is an increase in VI, AHW and TOD with an increase in gestational age (p-value < 0.001) and birth weight (p-value < 0.001). No significant correlation of gender and singleton or multiple gestation-with the intraventricular dimensions was observed (p-value > 0.05). All the three ventricular parameters were found to have a significantly lower mean value in the normal vaginal delivery group as compared to the LSCS group. There was a good correlation between ventricular indices of the left and right side. Nomograms of AHW, TOD, and VI were prepared with respect to gestational age.

CONCLUSIONS

Intracranial ventricular size dimensions vary significantly with increasing gestational age and birth weight. The new nomograms for various ventricular indices of Indian neonates can assist in objectively assessing ventricular sizes.

Integrating Clinical and Neuroimaging Markers to Predict the Onset of Posthemorrhagic Ventricular Dilatation in Preterm Neonates

BACKGROUND

Posthemorrhagic ventricular dilatation (PHVD) is a major complication of intraventricular hemorrhage (IVH); it is associated with high risks of cerebral palsy and cognitive deficits compared with infants without PHVD. This study aims to explore the early perinatal risk factors-associated with the risk of progressive PHVD.

METHODS

Neonates ≤29 weeks gestational age (GA) with Grade II-III IVH and periventricular hemorrhagic infarct (PVHI) between 2015 and 2021 were retrospectively reviewed. All cranial ultrasounds done within 14 days postnatal age (PNA) were assessed for grade of IVH, anterior horn width (AHW), ventricular index (VI), and thalamo-occipital index (TOD). The outcome was defined as death of any cause or VI and/or AHW and/or TOD ≥ moderate-risk zone based on an ultrasound done beyond two weeks PNA.

RESULTS

A total of 146 infants with a mean GA of 26 ± 1.8 weeks, birth weight 900 ± 234 g were included, 46% were females. The primary outcome occurred in 56 (39%) infants; among them 17 (30%) and 11 (20%) needed ventricular reservoir and shunt insertion, respectively. The risk factors present within 14 days PNA that significantly increased the odds of developing PHVD were hemodynamically significant patent ductus arteriosus (odds ratio [OR] 6.1, 95% confidence interval [CI] 1.9 to 22), culture-proven sepsis (OR 5.4, 95% CI 1.8 to 18), Grade III IVH (OR 4.6, 95% CI 1.1 to 22), PVHI (OR 3.0, 95% CI 0.9 to 10), and VI (OR 2.1, 95% CI 1.6 to 2.9).

CONCLUSIONS

Clinical predictors such as significant ductus arteriosus and bacterial septicemia, along with risk levels of AHW and VI measured with early cranial ultrasounds, are potential predictors of subsequent onset of PHVD.

Standardizing clinician training and patient care in the neonatal neurocritical care: A step-by-step guide

Neonatal neurocritical care (NNCC) has emerged as an important specialty to address neurological conditions affecting newborns including a wide spectrum of brain injuries and developmental impairment. Despite the discipline's growth, variability in NNCC service delivery, patient care, and clinical training poses significant challenges and potentially adversely impacts patient outcomes. Variations in neuroprotective strategies, postnatal care, and training methodologies highlight the urgent need for a unified approach to optimize both short- and long-term neurodevelopmental outcomes for these vulnerable population. This paper presents strategic blueprints for establishing standardized NNCC clinical care and training programs focusing on collaborative effort across medical and allied health professions. By addressing these inconsistencies, the paper proposes that standardizing NNCC practices can significantly enhance the quality of care, streamline healthcare resource utilization, and improve neurodevelopmental outcome, thus paving the way for a new era of neonatal neurological care.

Prediction of post-hemorrhagic ventricular dilatation trajectory using a growth mixture model in preterm infants

BACKGROUND

Early intervention for post-hemorrhagic ventricular dilatation (PHVD), guided by ventricular size measurements from cranial ultrasound (cUS), is associated with improved neurodevelopmental outcomes in preterm infants but benefits must be balanced against intervention risks.

METHODS

Anterior horn width (AHW) and ventricular index (VI) were measured from cUS for preterm infants (<29 weeks) with intraventricular hemorrhage admitted from 2010-2018. PHVD was defined as AHW > 6 mm or VI >97th percentile for postmenstrual age. Individual ventricular size trajectories were plotted, and a growth mixture model (GMM) used to identify latent trajectory classes and compare these to predetermined outcome of neurosurgical intervention.

RESULTS

Measurements were obtained from 1543 cUS in 249 infants, of whom 39 had PHVD without and 17 PHVD with neurosurgical intervention based on signs of raised intracranial pressure. The GMM predicted trajectory identified: 93.3% of infants without PHVD, 88.2% and 30.8% of infants with PHVD with and without intervention using AHW; 100% of infants without PHVD, 52.9% and 59.0% of infants with PHVD with and without intervention using VI.

CONCLUSIONS

The AHW GMM identified a significant proportion of infants with severe PHVD. Model refinement offers a promising approach for identifying differences in PHVD trajectory at an early stage to guide management.

IMPACT

It is difficult to distinguish the trajectory of PHVD in the early stage of development, in particular PHVD that spontaneously arrests from slowly progressive PHVD which eventually requires intervention. We report the first modeling-based evaluation of PHVD trajectory for the prediction of short-term outcome of PHVD progression and neurosurgical intervention. With additional clinical validation and optimization to increase accuracy, predictive modeling has the potential to identify important differences in PHVD trajectory at an early stage in the clinical course, allowing for more individualized data-driven risk-benefit assessments to guide decisions on early intervention.

Negative central activity in extremely preterm newborns: EEG characterization and relationship with brain injuries and neurodevelopmental outcome

OBJECTIVE

To characterize Negative Central Activity (NCA), an overlooked electroencephalographic activity of preterm newborns and investigate its relationship with brain injuries, dysfunction, and neurodevelopmental outcome.

METHODS

109 preterm infants (23-28 weeks) were retrospectively included. NCA were selected at the negative peak on EEG. Individual averaged NCA were automatically characterized. Brain structural data were collected from cranial ultrasounds (cUS). The neurodevelopmental outcome at two years of age was assessed by the Denver Developmental Screening Test-II.

RESULTS

Thirty-six (33%) children showed NCA: 6,721 NCA were selected, a median of 75 (interquartile range, 25/157.3) per EEG. NCA showed a triphasic morphology, with a mean amplitude and duration of the negative component of 24.6-40.0 µV and 222.7-257.3 ms. The presence of NCA on EEG was associated with higher intraventricular haemorrhage (IVH) grade on the first (P = 0.016) and worst neonatal cUS (P < 0.001) and poorer neurodevelopmental outcome (P < 0.001).

CONCLUSIONS

NCA is an abnormal EEG feature of extremely preterm newborns that may correspond to the functional neural impact of a vascular pathology.

SIGNIFICANCE

The NCA relationships with an adverse outcome and the presence/severity of IVH argue for considering NCA in the assessment of pathological processes in the developing brain network and for early outcome prediction.

Neurosonography: Shaping the future of neuroprotection strategies in extremely preterm infants

This review aims to explore the current application of Cranial Ultrasound Screening (CUS) in the diagnosis and treatment of brain diseases in extremely preterm infants. It also discusses the potential role of emerging ultrasound-derived technologies such as Super Microvascular Structure Imaging (SMI), Shear Wave Elastography (SWE), Ultrafast Doppler Ultrasound (UfD), and 3D ventricular volume assessment and automated segmentation techniques in clinical practice. A systematic search of medical databases was conducted using the keywords "(preterm OR extremely preterm OR extremely low birth weight) AND (ultrasound OR ultrasound imaging) AND (neurodevelopment OR brain development OR brain diseases OR brain injury OR neuro*)" to identify relevant literature. The titles, abstracts, and full texts of the identified articles were carefully reviewed to determine their relevance to the research topic. CUS offers unique advantages in early screening and monitoring of brain diseases in extremely preterm infants, as it can be performed at the bedside without the need for anesthesia or special monitoring. This technique facilitates early detection and intervention of conditions such as intraventricular hemorrhage, white matter injury, hydrocephalus, and hypoxic-ischemic injury in critically ill preterm infants. Continuous refinement of the screening and follow-up processes provides reliable clinical decision-making support for healthcare professionals and parents. Emerging ultrasound technologies, such as SWE, SMI, and UfD, are being explored to provide more accurate and in-depth understanding of brain diseases in extremely preterm infants. SWE has demonstrated its effectiveness in assessing the elasticity of neonatal brain tissue, aiding in the localization and quantification of potential brain injuries. SMI can successfully identify microvascular structures in the brain, offering a new perspective on neurologic diseases. UfD provides a high-sensitivity and quantitative imaging method for the prevention and treatment of neonatal brain diseases by detecting subtle changes in red blood cell movement and accurately assessing the status and progression of brain diseases. CUS and its emerging technologies have significant applications in the diagnosis and treatment of brain diseases in extremely preterm infants. Future research aims to address current technical challenges, optimize and enhance the clinical decision-making capabilities related to brain development, and improve the prevention and treatment outcomes of brain diseases in extremely preterm infants.

Cranial Point-of-Care Ultrasound for Neonatal Providers: A Feasibility Study

OBJECTIVE

Despite strong evidence for its utility in clinical management and diagnosis of intracranial hemorrhage (ICH), the use of neonatal cranial point-of-care ultrasound (POCUS) has not been standardized in neonatal intensive care units (NICUs) in the United States. The primary aim of this study was to evaluate the feasibility of training NICU providers to perform cranial POCUS by tracking the quality of image acquisition following training.

METHODS

Observational single-center cohort study of cranial POCUS images obtained by trained neonatal practitioners (attendings, fellows, and advanced practice providers) using a protocol developed by a radiologist and neonatologist. Exams were performed on infants born ≤1250 g and/or ≤30 weeks gestation within the first 3 days after birth. A survey to assess attitudes regarding cranial POCUS was given before each of three training sessions. Demographic and clinical data collection were portrayed with descriptive statistics. Metrics of image quality were assessed by a radiologist and sonographer independently. Analysis of trends in quality of POCUS images over time was performed using a multinomial Cochran-Armitage test.

RESULTS

Eighty-two cranial POCUS scans were performed over a 2-year period. Infant median age at exam was 14 hours (IQR 7-22 hours). Metrics of image quality depicted quarterly demonstrated a significant improvement in depth (P = .01), gain (P = .048), and quality of anatomy images captured (P < .001) over time. Providers perceived increased utility and safety of cranial POCUS over time.

CONCLUSION

Cranial POCUS image acquisition improved significantly following care team training, which may enable providers to diagnose ICH at the bedside.

Association of low hemoglobin at birth and neurodevelopmental outcomes in preterm neonates ≤28 weeks' gestation: a retrospective cohort study

OBJECTIVE

To compare neurodevelopmental outcomes at 18-24 months corrected age (CA) for preterm infants who had hemoglobin levels <120 g/l versus those with hemoglobin level ≥120 g/l at birth.

METHODS

We included infants of ≤28 weeks gestational age (GA) born between January 2009 and June 2018. The primary outcome was neurodevelopmental impairment (NDI) at 18-24 months. Multivariable logistic regression was applied to determine the association.

RESULTS

Of the 2351 eligible neonates, 351 (14.9%) had hemoglobin levels <120 g/L at birth. Of the 2113 surviving infants, 1534 (72.5%) underwent developmental follow-up at 18-24 months CA. There was no statistically significant difference in ND outcomes between the two groups. The composite outcome of death or NDI was significantly higher in the low hemoglobin group.

CONCLUSION

In preterm infants ≤28 weeks GA, initial hemoglobin <120 g/L at birth was not associated with neurodevelopmental impairment at 18-24 months CA among survivors.

Training in neonatal neurocritical care: A case-based interdisciplinary approach

Interdisciplinary fetal-neonatal neurology (FNN) training strengthens neonatal neurocritical care (NNCC) clinical decisions. Neonatal neurological phenotypes require immediate followed by sustained neuroprotective care path choices through discharge. Serial assessments during neonatal intensive care unit (NICU) rounds are supplemented by family conferences and didactic interactions. These encounters collectively contribute to optimal interventions yielding more accurate outcome predictions. Maternal-placental-fetal (MPF) triad disease pathways influence postnatal medical complications which potentially reduce effective interventions and negatively impact outcome. The science of uncertainty regarding each neonate's clinical status must consider timing and etiologies that are responsible for fetal and neonatal brain disorders. Shared clinical decisions among all stakeholders' balance "fast" (heuristic) and "slow" (analytic) thinking as more information is assessed regarding etiopathogenetic effects that impair the developmental neuroplasticity process. Two case vignettes stress the importance of FNN perspectives during NNCC that integrates this dual cognitive approach. Clinical care paths evaluations are discussed for an encephalopathic extremely preterm and full-term newborn. Recognition of cognitive errors followed by debiasing strategies can improve clinical decisions during NICU care. Re-evaluations with serial assessments of examination, imaging, placental-cord, and metabolic-genetic information improve clinical decisions that maintain accuracy for interventions and outcome predictions. Discharge planning includes shared decisions among all stakeholders when coordinating primary care, pediatric subspecialty, and early intervention participation. Prioritizing social determinants of healthcare during FNN training strengthens equitable career long NNCC clinical practice, education, and research goals. These perspectives contribute to a life course brain health capital strategy that will benefit all persons across each and successive lifespans.

Transforming neonatal care with artificial intelligence: challenges, ethical consideration, and opportunities

Artificial intelligence (AI) offers tremendous potential to transform neonatology through improved diagnostics, personalized treatments, and earlier prevention of complications. However, there are many challenges to address before AI is ready for clinical practice. This review defines key AI concepts and discusses ethical considerations and implicit biases associated with AI. Next we will review literature examples of AI already being explored in neonatology research and we will suggest future potentials for AI work. Examples discussed in this article include predicting outcomes such as sepsis, optimizing oxygen therapy, and image analysis to detect brain injury and retinopathy of prematurity. Realizing AI's potential necessitates collaboration between diverse stakeholders across the entire process of incorporating AI tools in the NICU to address testability, usability, bias, and transparency. With multi-center and multi-disciplinary collaboration, AI holds tremendous potential to transform the future of neonatology.

Practical Stepwise Approach to Performing Neonatal Brain MR Imaging in the Research Setting

Magnetic resonance imaging (MRI) is a non-invasive imaging technique that is commonly used for the visualization of newborn infant brains, both for clinical and research purposes. One of the main challenges with scanning newborn infants, particularly when scanning without sedation in a research setting, is movement. Infant movement can affect MR image quality and therewith reliable image assessment and advanced image analysis. Applying a systematic, stepwise approach to MR scanning during the neonatal period, including the use of the feed-and-bundle technique, is effective in reducing infant motion and ensuring high-quality images. We provide recommendations for one such systematic approach, including the step-by-step preparation and infant immobilization, and highlight safety precautions to minimize any potential risks. The recommendations are primarily focused on scanning newborn infants for research purposes but may be used successfully for clinical purposes as well, granted the infant is medically stable. Using the stepwise approach in our local research setting, our success rate of acquiring high-quality, analyzable infant brain MR images during the neonatal period is as high as 91%.

Evaluation of a Cranial Ultrasound Screening Protocol for Very Preterm Infants

OBJECTIVES

Cranial ultrasound (cUS) screening is recommended for preterm neonates born before 32 weeks' gestational age (GA). The primary aim of this study was to determine if both a day 3 and day 8 cUS screening examination is necessary for all neonates.

METHODS

A retrospective observational study was performed at a tertiary-level Australian hospital. Frequencies of cranial ultrasound abnormality (CUA) were compared between routine screening performed at postnatal days 3, 8, and 42. Univariate and multivariate analyses of risk factors for intraventricular hemorrhage (IVH) was performed using logistic regression.

RESULTS

cUS examinations on 712 neonates born before 32 weeks' GA were included. Neonates were divided into 2 groups: 99 neonates in the 23-25 weeks 6 days GA (group A) and 613 neonates in the 26-31 weeks 6 days GA (group B). All CUA occurred more frequently in group A neonates and in the subset of group B neonates who had defined risk factors. Low-risk group B neonates had lower incidence of CUAs demonstrated on day 8 cUS than high-risk group B neonates, with no significant differences between day 3 and day 8. Logistic regression analysis identified a number of risk factors (vaginal delivery, small for GA, Apgar score <7 at 5 minutes, intubation, patent ductus arteriosus and infection) that were associated with increased frequency of IVH on day 8. In neonates born between 30 and 31 weeks 6 days GA, 35% had a CUA identified.

CONCLUSIONS

Low-risk preterm neonates born between 26 and 31 weeks 6 days GA, without complications, could be screened with a single early cUS examination around day 8 without missing substantial abnormality.

Predicting the Neurodevelopmental Outcome in Extremely Preterm Newborns Using a Multimodal Prognostic Model Including Brain Function Information

IMPORTANCE

Early assessment of the prognosis of preterm newborns is crucial for accurately informing parents and making treatment decisions. The currently available prognostic models rarely incorporate functional brain information from conventional electroencephalography (cEEG).

OBJECTIVE

To examine the performance of a multimodal model combining (1) brain function information with (2) brain structure information (cranial ultrasonography), and (3) perinatal and (4) postnatal risk factors for the prediction of death or neurodevelopmental impairment (NDI) in extremely preterm infants.

DESIGN, SETTING, AND PARTICIPANTS

Preterm newborns (23-28 weeks' gestational age) admitted to the neonatal intensive care unit at Amiens-Picardie University Hospital were retrospectively included (January 1, 2013, to January 1, 2018). Risk factors from the 4 categories were collected during the first 2 weeks post delivery. Neurodevelopmental impairment was assessed at age 2 years with the Denver Developmental Screening Test II. No or moderate NDI was considered a favorable outcome. Death or severe NDI was considered an adverse outcome. Data analysis was performed from August 26, 2021, to March 31, 2022.

MAIN OUTCOMES AND MEASURES

After the selection of variables significantly associated with outcome, 4 unimodal prognostic models (considering each category of variable independently) and 1 multimodal model (considering all variables simultaneously) were developed. After a multivariate analysis for models built with several variables, decision-tree algorithms were run on each model. The areas under the curve for decision-tree classifications of adverse vs favorable outcomes were determined for each model, compared using bootstrap tests, and corrected for type I errors.

RESULTS

A total of 109 newborns (58 [53.2% male]) born at a mean (SD) gestational age of 26.3 (1.1) weeks were included. Among them, 52 (47.7%) had a favorable outcome at age 2 years. The multimodal model area under the curve (91.7%; 95% CI, 86.4%-97.0%) was significantly higher than those of the unimodal models (P < .003): perinatal model (80.6%; 95% CI, 72.5%-88.7%), postnatal model (81.0%; 95% CI, 72.6%-89.4%), brain structure model (cranial ultrasonography) (76.6%; 95% CI, 67.8%-85.3%), and brain function model (cEEG) (78.8%; 95% CI, 69.9%-87.7%).

CONCLUSIONS AND RELEVANCE

In this prognostic study of preterm newborns, the inclusion of brain information in a multimodal model was associated with significant improvement in the outcome prediction, which may have resulted from the complementarity of the risk factors and reflected the complexity of the mechanisms that interfered with brain maturation and led to death or NDI.

Variability in the diagnostic and management practices of post-hemorrhagic ventricular dilatation in very preterm infants across Canadian centers and comparison with European practices

OBJECTIVES

To investigate the variability in diagnostic and therapeutic approaches to posthemorrhagic ventricular dilatation (PHVD) among Canadian neonatal centers, and secondary exploration of differences in approaches between Canadian and European practices.

METHODS

We conducted a survey among Canadian tertiary neonatal centers on their local practices for managing very preterm infants with PHVD. The survey covered questions on the diagnostic criteria, timing and type of interventions and resources utilization (transfer to neurosurgical sites and neurodevelopmental follow-up). In a secondary exploration, Canadian responses were compared with responses to the same survey from European centers.

RESULTS

23/30 Canadian centers (77%) completed the survey. There was no consensus among Canadian centers on the criteria used for diagnosing PHVD or to initiate intervention. The therapeutic interventions also vary, both for temporizing procedures or permanent shunting. Compared to European practices, the Canadian approach relied less on the sole use of ultrasound criteria for diagnosing PHVD (43 vs 94%, p < 0.0001) or timing intervention (26 vs 63%, p = 0.007). Majority of European centers intervened early in the development of PHVD based on ultrasound parameters, whereas Canadian centers intervened based on clinical hydrocephalus, with fewer centers performing serial lumbar punctures prior to neurosurgical procedures (40 vs 81%, p = 0.003).

CONCLUSION

Considerable variability exists in diagnosis and management of PHVD in preterm infants among Canadian tertiary centers and between Canadian and European practices. Given the potential implications of the inter-center practice variability on the short- and long-term outcomes of preterm infants with PHVD, efforts towards evidence-based Canada-wide practice standardization are underway.

Cranial Ultrasound Abnormalities in Small for Gestational Age or Growth-Restricted Infants Born over 32 Weeks Gestation: A Systematic Review and Meta-Analysis

AIM

To perform a systematic review and meta-analysis of existing literature to evaluate the incidence of cranial ultrasound abnormalities (CUAs) amongst moderate to late preterm (MLPT) and term infants, affected by fetal growth restriction (FGR) or those classified as small for gestational age (SGA).

METHODS

A systematic review methodology was performed, and Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) statement was utilised. Descriptive and observational studies reporting cranial ultrasound outcomes on FGR/SGA MLPT and term infants were included. Primary outcomes reported was incidence of CUAs in MLPT and term infants affected by FGR or SGA, with secondary outcomes including brain structure development and growth, and cerebral artery Dopplers. A random-effects model meta-analysis was performed. Risk of Bias was assessed using the Newcastle-Ottawa scale for case-control and cohort studies, and Joanna Briggs Institute Critical Appraisal Checklist for studies reporting prevalence data. GRADE was used to assess for certainty of evidence.

RESULTS

Out of a total of 2085 studies identified through the search, seventeen were deemed to be relevant and included. Nine studies assessed CUAs in MLPT FGR/SGA infants, seven studies assessed CUAs in late preterm and term FGR/SGA infants, and one study assessed CUAs in both MLPT and term FGR/SGA infants. The incidence of CUAs in MLPT, and late preterm to term FGR/SGA infants ranged from 0.4 to 33% and 0 to 70%, respectively. A meta-analysis of 7 studies involving 168,136 infants showed an increased risk of any CUA in FGR infants compared to appropriate for gestational age (AGA) infants (RR 1.96, [95% CI 1.26-3.04], I² = 68%). The certainty of evidence was very low due to non-randomised studies, methodological limitations, and heterogeneity. Another meta-analysis looking at 4 studies with 167,060 infants showed an increased risk of intraventricular haemorrhage in FGR/SGA infants compared to AGA infants (RR 2.40, [95% CI 2.03-2.84], I² = 0%). This was also of low certainty.

CONCLUSIONS

The incidence of CUAs in MLPT and term growth-restricted infants varied widely between studies. Findings from the meta-analyses suggest the risk of CUAs and IVH may indeed be increased in these FGR/SGA infants when compared with infants not affected by FGR, however the evidence is of low to very low certainty. Further specific cohort studies are needed to fully evaluate the benefits and prognostic value of cranial ultrasonography to ascertain the need for, and timing of a cranial ultrasound screening protocol in this infant population, along with follow-up studies to ascertain the significance of CUAs identified.

Optimizing timing and frequency of head ultrasound screening for severe brain injury among preterm infants born <32 weeks' gestation

OBJECTIVE

To develop a head ultrasound (HUS) screening protocol for infants born <32 weeks gestational age (GA) that accurately identifies severe brain injury (SBI) while minimizing resource use.

STUDY DESIGN

Retrospective cohort study of infants born <32 weeks GA, admitted to a level 3 neonatal intensive care unit between 2011 and 2017. Timing and results of each HUS were reviewed. SBI was defined as intraventricular hemorrhage grade ≥3 and/or periventricular leukomalacia. Logistic regression models were used to identify risk factors and evaluate the predictive value of HUS at different time points during hospitalization.

RESULTS

Of 651 included infants, 71 (11%) developed SBI. Risk factors for SBI were GA at birth <29 weeks (adjusted odds ratio (aOR) 2.87, 95% confidence interval (CI) 1.50-5.48), vasopressors on admission (aOR 3.08, 95%CI 1.38-6.88) and mechanical ventilation on admission (aOR 2.50, 95%CI 1.33-4.68). Infants were classified into three risk groups based on these risk factors, and combinations of 1-5 HUS time points were evaluated to determine the optimal number and timing of HUS for each group. The optimal number of screening HUS ranged from 1 for low-risk to 2 for high-risk infants. Adopting a screening protocol using the number and timing of HUS optimized by risk group could reduce the total number of HUS performed by 40% and the median number of HUS per infant from 3 (IQR 2-4) to 2 (IQR 1-3) (p < .01).

CONCLUSIONS

Implementation of a risk factor-based HUS screening protocol can help reduce resource use while maintaining high sensitivity for detecting SBI.

Impact of quality improvement outreach education on the incidence of acute brain injury in transported neonates born premature

OBJECTIVE

To evaluate impact of a quality improvement (QI) outreach education on incidence of acute brain injury in transported premature neonates.

STUDY DESIGN

Neonates born at &lt;33 weeks gestation outside the tertiary center were included. The QI intervention was a combination of neuroprotection care bundle, in-person visits, and communication system improvement. Descriptive and regression (adjusting for Gestational Age, Birth Weight, Gender, and antenatal steroids, Mode of delivery, Apgars at 5 minutes, Prophylactic indomethacin, PDA, and Inotropes use) analyses were performed. The primary outcome was a composite of death and/or severe brain injury on cranial ultrasound using a validated classification.

RESULTS

181 neonates studied (93 before and 88 after). The rate and adjusted odds of death and/or severe brain injury reduced significantly post intervention (30% vs 15%) and (AOR 0.36, 95%CI, 0.15-0.85, P = 0.02) respectively.

CONCLUSION

Implementation of outreach education targeting neuroprotection can reduce acute brain injury in transported premature neonates.

Diffuse correlation spectroscopy blood flow monitoring for intraventricular hemorrhage vulnerability in extremely low gestational age newborns

In premature infants with an extremely low gestational age (ELGA, < 29 weeks GA), dysregulated changes in cerebral blood flow (CBF) are among the major pathogenic factors leading to germinal matrix/intraventricular hemorrhage (GM/IVH). Continuous monitoring of CBF can guide interventions to minimize the risk of brain injury, but there are no clinically standard techniques or tools for its measurement. We report the feasibility of the continuous monitoring of CBF, including measures of autoregulation, via diffuse correlation spectroscopy (DCS) in ELGA infants using CBF variability and correlation with scalp blood flow (SBF, served as a surrogate measure of systemic perturbations). In nineteen ELGA infants (with 9 cases of GM/IVH) monitored for 6–24 h between days 2–5 of life, we found a strong correlation between CBF and SBF in severe IVH (Grade III or IV) and IVH diagnosed within 72 h of life, while CBF variability alone was not associated with IVH. The proposed method is potentially useful at the bedside for the prompt assessment of cerebral autoregulation and early identification of infants vulnerable to GM/IVH.

The predictive ability of the Lacey Assessment of Preterm Infants (LAPI), Cranial Ultrasound (cUS) and General Movements Assessment (GMA) for Cerebral Palsy (CP): A prospective, clinical, single center observational study

BACKGROUND AND AIM

The LAPI, cUS and GMA are assessments used clinically in the UK to identify preterm infants at high risk of neurodevelopmental disabilities such as cerebral palsy. This study investigated the ability of these assessments to predict cerebral palsy at 2 years corrected gestational age.

METHODS

Design: Prospective longitudinal cohort study including infants born <30 weeks' gestation from a single tertiary neonatal intensive care unit. The LAPI and cUS were undertaken as part of routine care before term equivalent age and the GMA was undertaken at 11-18 weeks corrected gestational age.

RESULTS

There were 123 eligible infants and 95 infants (77.2%) were included. Thirteen infants (13.7%) had a diagnosis of CP at 2 years. There was no significant difference in gestational age, gender, or birth weight between the groups with and without a diagnosis of CP. The highest accuracy of prediction of CP was achieved by an aberrant, absent fidgety general movements classification with a sensitivity of 92.3% and specificity of 98.9%. Combining the GMA to include the cUS or LAPI did not increase the predictive accuracy.

CONCLUSION

The GMA when undertaken in clinical practice had high accuracy for predicting CP at 2 years corrected age in infants born <30 weeks gestation; LAPI and cUS did not improve this accuracy.

Neonatologist-Performed Cranial Ultrasonography in the Neonatal Intensive Care Unit

Cranial ultrasound (CUS) is an initial screening imaging tool used to evaluate the neonatal brain. It is an accessible, inexpensive, and harmless technique that can be used at bedside as frequently as required. Timely focused CUS in the neonatal care unit can play a major role in the diagnosis, follow-up, and management of brain damage. Despite the increasing use of point-of-care ultrasonography by intensive care physicians, neonatologist-performed CUS remains unusual. This review aims to provide an overview of neonatal CUS to neonatologists, focusing on the optimal settings, standard planes of the brain, and main pathologies in preterm infants. Adding Doppler studies allows evaluation of the patency of intracranial arteries and veins, flow velocities, and indices. This may provide an opportunity for earlier targeted circulatory support to prevent brain injury and improve long-term neurodevelopmental outcomes.

Fetal Brain Development: Regulating Processes and Related Malformations

This paper describes the contemporary state of knowledge regarding processes that regulate normal development of the embryonic–fetal central nervous system (CNS). The processes are described according to the developmental timetable: dorsal induction, ventral induction, neurogenesis, neuronal migration, post-migration neuronal development, and cortical organization. We review the current literature on CNS malformations associated with these regulating processes. We specifically address neural tube defects, holoprosencephaly, malformations of cortical development (including microcephaly, megalencephaly, lissencephaly, cobblestone malformations, gray matter heterotopia, and polymicrogyria), disorders of the corpus callosum, and posterior fossa malformations. Fetal ventriculomegaly, which frequently accompanies these disorders, is also reviewed. Each malformation is described with reference to the etiology, genetic causes, prenatal sonographic imaging, associated anomalies, differential diagnosis, complimentary diagnostic studies, clinical interventions, neurodevelopmental outcome, and life quality.

Hemodynamic Quality Improvement Bundle to Reduce the Use of Inotropes in Extreme Preterm Neonates

BACKGROUND

We evaluated the effect of the quality improvement (QI) bundle on the rate of inotrope use and associated morbidities.

METHODS

We included inborn preterm neonates born at < 29 weeks admitted to level III NICU. We implemented a QI bundle focusing on the first 72 h from birth which included delayed cord clamping, avoidance of routine echocardiography, the addition of clinical criteria to the definition of hypotension, factoring iatrogenic causes of hypotension, and standardization of respiratory management. The rate of inotropes use was compared before and after implementing the care bundle. Incidence of cystic periventricular leukomalacia (cPVL) was used as a balancing measure.

RESULTS

QI bundle implementation was associated with significant reduction in overall use of inotropes (24 vs 7%, p < 0.001), dopamine (18 vs 5%, p < 0.001), and dobutamine (17 vs 4%, p < 0.001). Rate of acute brain injury decreased significantly: acute brain injury of any grade (34 vs 20%, p < 0.001) and severe brain injury (15 vs 6%, p < 0.001). There was no difference in the incidence of cPVL (0.8 vs 1.4%, p = 0.66). Associations remained significant after adjusting for confounding factors.

CONCLUSIONS

A quality improvement bundled approach resulted in a reduction in inotropes use and associated brain morbidities in premature babies.

School Readiness in 4-Year-Old Very Preterm Children

The aims of this study were to identify the aspects of school readiness that best distinguish very preterm (VPT) preschoolers from full-term (FT) controls, determine the extent to which readiness problems in the VPT group reflected global cognitive weaknesses or more specific deficits, and identify distinct profiles of readiness problems. Fifty-three VPT (gestational age ≤ 30 weeks) 4-year-olds were compared to 38 FT (gestational age ≥ 37 weeks) controls on measures of global cognitive ability, executive function, motor skills, early literacy and numeracy, and psychosocial functioning. Latent class analysis (LCA) was also conducted to identify individual readiness profiles. The VPT group had the most pronounced difficulties on tests of spatial and nonverbal cognitive abilities, executive function, motor skills, phonological processing, and numeracy. The VPT group also had sex-related difficulties in processing speed, social functioning, and emotion regulation. These differences were evident in analyses of both continuous scores and rates of deficits. The VPT group’s difficulties in motor skills, and VPT females’ difficulties in social functioning and emotion regulation, were evident even when controlling for global cognitive ability. LCA suggested four profiles of readiness, with the majority of the VPT group assigned to profiles characterized by relative weaknesses in either cognitive abilities or psychosocial functioning or by more global readiness problems. The findings support the need to evaluate multiple aspects of school readiness in VPT preschoolers and inform efforts to design more targeted early educational interventions.

A Narrative Review of Circular RNAs in Brain Development and Diseases of Preterm Infants

Circular RNAs (circRNAs) generated by back-splicing are the vital class of non-coding RNAs (ncRNAs). Circular RNAs are highly abundant and stable in eukaryotes, and many of them are evolutionarily conserved. They are blessed with higher expression in mammalian brains and could take part in the regulation of physiological and pathophysiological processes. In addition, premature birth is important in neurodevelopmental diseases. Brain damage in preterm infants may represent the main cause of long-term neurodevelopmental disorders in surviving babies. Until recently, more and more researches have been evidenced that circRNAs are involved in the pathogenesis of encephalopathy of premature. We aim at explaining neuroinflammation promoting the brain damage. In this review, we summarize the current findings of circRNAs properties, expression, and functions, as well as their significances in the neurodevelopmental impairments, white matter damage (WMD) and hypoxic-ischemic encephalopathy (HIE). So we think that circRNAs have a direct impact on neurodevelopment and brain injury, and will be a powerful tool in the repair of the injured immature brain. Even though their exact roles and mechanisms of gene regulation remain elusive, circRNAs have potential applications as diagnostic biomarkers for brain damage and the target for neuroprotective intervention.