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Introduction: Brain injury patterns of preterm infants with perinatal asphyxia (PA) are underreported. We aimed to explore brain magnetic resonance imaging (MRI) findings and associated neurodevelopmental outcomes in these newborns. Methods: Retrospective multicenter study included infants with gestational age (GA) 24.0–36.0 weeks and PA, defined as ≥2 of the following: (1) umbilical cord pH ≤7.0, (2) 5-min Apgar score ≤5, and (3) fetal distress or systemic effects of PA. Findings were compared between GA <28.0 (group 1), 28.0–31.9 (group 2), and 32.0–36.0 weeks (group 3). Early MRI (<36 weeks postmenstrual age or <10 postnatal days) was categorized according to predominant injury pattern, and MRI around term-equivalent age (TEA, 36.0–44.0 weeks and ≥10 postnatal days) using the Kidokoro score. Adverse outcomes included death, cerebral palsy, epilepsy, severe hearing/visual impairment, or neurodevelopment <-1 SD at 18–24 months corrected age. Results: One hundred nineteen infants with early MRI (n = 94) and/or MRI around TEA (n = 66) were included. Early MRI showed predominantly hemorrhagic injury in groups 1 (56%) and 2 (45%), and white matter (WM)/watershed injury in group 3 (43%). Around TEA, WM scores were highest in groups 2 and 3. Deep gray matter (DGM) (aOR 15.0, 95% CI: 3.8–58.9) and hemorrhagic injury on early MRI (aOR 2.5, 95% CI: 1.3–4.6) and Kidokoro WM (aOR 1.3, 95% CI: 1.0–1.6) and DGM sub-scores (aOR 4.8, 95% CI: 1.1–21.7) around TEA were associated with adverse neurodevelopmental outcomes. Conclusion: The brain injury patterns following PA in preterm infants differ across GA. Particularly DGM abnormalities are associated with adverse neurodevelopmental outcomes. [ABSTRACT FROM AUTHOR]

In recent years, exploration of the developing brain has become a major focus for researchers and clinicians in an attempt to understand what allows children to acquire amazing and unique abilities, as well as the impact of early disruptions (eg, prematurity, neonatal insults) that can lead to a wide range of neurodevelopmental disorders. Noninvasive neuroimaging methods such as MRI are essential to establish links between the brain and behavioral changes in newborns and infants. In this review article, we aim to highlight recent and representative studies using the various techniques available: anatomical MRI, quantitative MRI (relaxometry, diffusion MRI), multiparametric approaches, and functional MRI. Today, protocols use 1.5 or 3T MRI scanners, and specialized methodologies have been put in place for data acquisition and processing to address the methodological challenges specific to this population, such as sensitivity to motion. MR sequences must be adapted to the brains of newborns and infants to obtain relevant good soft-tissue contrast, given the small size of the cerebral structures and the incomplete maturation of tissues. The use of age-specific image postprocessing tools is also essential, as signal and contrast differ from the adult brain. Appropriate methodologies then make it possible to explore multiple neurodevelopmental mechanisms in a precise way, and assess changes with age or differences between groups of subjects, particularly through large-scale projects. Although MRI measurements only indirectly reflect the complex series of dynamic processes observed throughout development at the molecular and cellular levels, this technique can provide information on brain morphology, structural connectivity, microstructural properties of gray and white matter, and on the functional architecture. Finally, MRI measures related to clinical, behavioral, and electrophysiological markers have a key role to play from a diagnostic and prognostic perspective in the implementation of early interventions to avoid long-term disabilities in children. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY STAGE: 1. [ABSTRACT FROM AUTHOR]

Background: Magnetic resonance imaging (MRI) is the standard neuroimaging technique to assess perinatal asphyxia-associated brain injury in full-term infants. Diffusion-weighted imaging (DWI) is most informative when assessed during the first week after the insult. Objectives: To study the DWI abnormalities of the thalamus and basal ganglia in full-term infants with perinatal asphyxia. Methods: Fifty-five (near) term infants (normothermia n = 23; hypothermia n = 32) with thalamus and/or basal ganglia injury were included. MRI findings were assessed visually and quantitatively calculating apparent diffusion coefficient (ADC) values. Thalamus/basal ganglia ADC ratios were calculated to analyze the differences between these areas. Infants with an early MRI (days 1–3) or later MRI (days 4–7) were compared. Results: Isolated extensive thalamic injury was seen early, and focal thalamic and basal ganglia injury was seen later. On the early MRI, visual assessment underestimated abnormalities in the basal ganglia (59% abnormal vs. 90% abnormal on quantitative assessment; p = 0.015), suggesting the need for quantitative assessment. In infants treated with hypothermia, the thalamus/basal ganglia ADC ratio was lower. Conclusions: Both visual analysis and quantitative evaluation of cerebral MRI after perinatal asphyxia are needed, especially during the first few days after birth. Timing of ADC changes is influenced by therapeutic hypothermia. [ABSTRACT FROM AUTHOR]

Objective: Cranial magnetic resonance imaging (MRI) is associated with neurodevelopmental outcome in full-term infants with neonatal encephalopathy (NE) following presumed perinatal asphyxia. The aim of this study is to relate 2-dimensional measurements of the basal ganglia and thalami (BGT) and cerebellum in the first week after birth and after 3 months with neurodevelopmental outcome at 18 months. Methods: Retrospectively, 29 full-term infants with NE following presumed perinatal asphyxia who had a cranial MRI in the first week after birth were studied serially. One- and 2-dimensional measurements were obtained and related to different patterns of brain injury, and neurodevelopmental outcome at 18 months. A Griffiths developmental quotient <85 or cerebral palsy was considered adverse. Results: On the first MRI, the adverse outcome group showed increased basal ganglia width (42.1 ± 0.1 vs. 40.3 ± 0.3 mm, p < 0.001), thalamic width (40.3 ± 0.1 vs. 39.3 ± 1.0 mm, p < 0.001), and basal ganglia surface (1,230 ± 21 vs. 1,199 ± 36 mm2, p = 0.007) compared to the favorable outcome group. In the BGT lesions group, basal ganglia width and thalamic width were increased compared to the watershed infarction group (42.1 ± 0.1 vs. 40.9 ± 0.8 mm, p < 0.001, and 40.3 ± 0.1 vs. 39.9 ± 0.5 mm, p = 0.01, respectively). On the second MRI, cerebellar width was larger in the favorable outcome group (p = 0.025). There was a greater increase in dimensions between both MRI time points for basal ganglia width (p = 0.014), basal ganglia surface (p = 0.028) and thalamic width (p = 0.012) in the favorable outcome group. Conclusions: One- and 2-dimensional measurements for basal ganglia surface, BGT width and cerebellar width are associated with neurodevelopmental outcome at 18 months. [ABSTRACT FROM AUTHOR]

A number of algorithms for brain segmentation in preterm born infants have been published, but a reliable comparison of their performance is lacking. The NeoBrainS12 study ( http://neobrains12.isi.uu.nl ), providing three different image sets of preterm born infants, was set up to provide such a comparison. These sets are (i) axial scans acquired at 40 weeks corrected age, (ii) coronal scans acquired at 30 weeks corrected age and (iii) coronal scans acquired at 40 weeks corrected age. Each of these three sets consists of three T1- and T2-weighted MR images of the brain acquired with a 3T MRI scanner. The task was to segment cortical grey matter, non-myelinated and myelinated white matter, brainstem, basal ganglia and thalami, cerebellum, and cerebrospinal fluid in the ventricles and in the extracerebral space separately. Any team could upload the results and all segmentations were evaluated in the same way. This paper presents the results of eight participating teams. The results demonstrate that the participating methods were able to segment all tissue classes well, except myelinated white matter. [ABSTRACT FROM AUTHOR]

Germinal matrix-intraventricular haemorrhage (GMH-IVH) remains a serious problem in the very and extremely preterm infant. This article reviews current methods of diagnosis, treatment and neurodevelopmental outcome in preterm infants with low-grade and severe GMH-IVH. We conclude that there is still no consensus on timing of intervention and treatment of infants with GMH-IVH, whether or not complicated by post-haemorrhagic ventricular dilatation. The discrepancies between the studies underline the need for international collaboration to define the optimal strategy for these infants. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Summary: There is controversy in the literature about the value of brain imaging in neonates regarding the prediction of cerebral palsy (CP). The aim of this review was to unravel the myth that CP cannot be predicted by neuroimaging in neonates. Major intracranial lesions in the preterm infant should be recognized with sequential cranial ultrasound and will predict those with non-ambulatory CP. Magnetic resonance imaging (MRI) at term-equivalent age will refine the prediction by assessment of myelination of the posterior limb of the internal capsule. Prediction of motor outcome in preterm infants with subtle white matter injury remains difficult, even with conventional MRI. MRI is a better tool to predict outcome in the term infant with hypoxic-ischaemic encephalopathy or neonatal stroke. The use of diffusion-weighted imaging as an additional sequence adds to the predictive value for motor outcome. Sequential and dedicated neuroimaging should enable us to predict motor outcome in high risk newborns infants. [ABSTRACT FROM AUTHOR]

Objective: To identify clinical risk factors for punctate white matter lesions (PWML) on early magnetic resonance imaging (MRI) in 2 cohorts of newborns born extremely preterm in different neonatal centers.Study Design: A total of 250 newborns born preterm at less than 28 weeks of gestation (mean 26.4 ± 1.1 weeks) with an early MRI were identified from 2 neonatal centers, in Vancouver, Canada (cohort A, n = 100) and Utrecht, the Netherlands (cohort B, n = 150). Cohort A was imaged as part of a prospective research study and cohort B was imaged as part of routine clinical care. PWML were defined as cluster type foci of hyperintensity on T1-weighted imaging and were identified at a mean postmenstrual age of 31.1 (±1.9) weeks. Multivariable analysis was used to identify clinical factors predictive of PWML.Results: Cluster type PWML were found in 47 newborns born extremely preterm (18.8%) and were more common in cohort A (32%) than in cohort B (10%). Newborns in cohort A generally were sicker than those in cohort B. Multivariable analyses revealed that greater birth weight (B = 0.002; P < .02), grade II-III intraventricular hemorrhage (B = 0.83; P < .02), and cohort A (B = 1.34; P < .0001) were independent predictors of PWML.Conclusion: Several risk factors for PWML on early MRI were identified. The interaction among birth weight, intraventricular hemorrhage, and other aspects of postnatal illness as risk factors for PWML warrants further investigation in newborns born extremely preterm and may help to identify modifiable risk factors for PWML. [ABSTRACT FROM AUTHOR]