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Background: Cerebellar posterior lobes have been associated with cognitive skills such as language functioning. Children born very preterm (VPT) often have atypical language functions, but so far only total cerebellar volume has been associated with language functions, with contradicting results.

Objective: To ascertain whether total cerebellar structures or specific posterior lobular structures are associated with language ability of school-aged VPT children.

Method: Prospective cohort study of 42 school-aged VPT children without overt brain damage. Structural Magnetic Resonance Imaging was performed and Cerebellum Segmentation pipeline was used for segmentation of all lobuli separately. Narrative retelling assessment was performed and a language content and language structure score were extracted. For both language measures linear regression analysis was used to test the association with whole grey matter (GM) cerebellar volume and right Crus I+II GM volume. Gestational age and sex were entered as confounders.

Results: Whole cerebellar GM volume was not associated with language content nor with language structure, however, the association between right Crus I+II GM volume and language content did reach the level of significance.

Conclusion: Specific cerebellar lobuli seem to be associated with language functions in school-aged VPT children, while whole cerebellar volume is not. This study showed the importance of studying cerebellar lobules separately, rather than whole cerebellar volume only, in relation to language functions in VPT children without major handicaps.

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Background and aim

Post-natal dexamethasone is largely used for chronic lung disease treatment or prevention in preterm neonates. While dexamethasone has been associated with adverse neurocognitive outcomes, little is known on its potential effects on the developing brain structures. We aimed to investigate whether dexamethasone exposure in extremely preterm infants may be associated with specific abnormalities at brain magnetic resonance imaging (MRI).

Methods

Infants <28weeks’ gestational age (GA) and <1000g, admitted to the local NICU between 2008 and 2019 and undergone brain MRI at term-equivalent age were included in this retrospective study. MRI scans were reviewed using the Kidokoro scoring system. Based on dexamethasone exposure, the infants were stratified into two groups, and a between-group comparison of each sub-score was performed. A multivariate model was used to adjust the observed results for relevant covariates.

Results

Ninety infants were included; of these, 45 received dexamethasone treatment (cumulative dose: median 1.7 mg/kg, interquartile range 0.9-3.67 mg/kg). The clinical characteristics of the study groups are detailed in Table 1. Infants receiving dexamethasone had a significantly thinner corpus callosum compared to controls (p=0.018); no difference was observed for the other sub-scores (Table 2). The correlation between dexamethasone exposure and thinning of corpus callosum was confirmed (b=1.752, p=0.009) even after adjustment for GA, sex, Apgar at 5min and year of birth.

Conclusions

The present results suggest a possible association between post-natal dexamethasone and specific brain MRI abnormalities, such as a thinner corpus callosum. Targeted studies on larger cohorts are needed to validate these preliminary findings.

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BACKGROUND

Therapeutic hypothermia (HT) has improved neurodevelopmental outcome following neonatal encephalopathy (NE), but a proportion of infants still develop motor disability and cognitive impairment.

Thalamic Lac/NAA on proton magnetic resonance spectroscopy (¹H MRS) predicts Bayley two-year outcomes (0.39 threshold). Prechtl General Movements (GM) predicts disability in NE. This study compares the predictive accuracy of 5-14-day MRS Lac/NAA with term and/or three-month GM assessment in NE after HT.

METHODS

Term infants treated with HT for moderate-severe NE at University College London Hospital in 2012-15 were reviewed. Of 183 babies treated during this period, 69 babies underwent MRS, GM, and two-year neurodevelopmental assessment using Bayley III. Results were assessed using ANOVA.

RESULTS

All babies with normal term GM had Lac/NAA <0.39 (p=0.027), unlike babies with poor repertoire GM at term (p=0.098). Babies with fidgety movements (FM) at 12 weeks had Lac/NAA <0.39 (p=0.001). Lac/NAA predicted two-year motor outcome (p=0.002). Term GM predicted two-year language outcome (p=0.036), and three-month FM predicted cognitive (p=0.0003), language (p=0.011) and motor (p=0.001) outcomes. Combining MRS and GM did not improve outcome prediction.

CONCLUSIONS

Lac/NAA differed in babies with normal term GM and three-month FM compared to abnormal assessments. Three-month FM was highly predictive of two-year cognitive, language and motor outcomes. Combining Lac/NAA and FM did not improve outcome prediction; each measure was highly predictive of motor, cognitive and language outcomes. In settings without access to ¹H MRS at 5-10 days, FM at 3 months is a robust measure of two-year outcome in babies after HT for NE.

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Background and aims:

Biomarkers of cerebral damage are needed for accurate prognosis and early evaluation of new treatments in new-borns with hypoxic ischemic encephalopathy (HIE). Hyperpolarized ¹³C magnetic resonance imaging (MRI) is a novel method to quantify metabolism in vivo with unprecedented resolution. We aimed to investigate whether hyperpolarized ¹³C MRI can be used in piglets and detect early changes in metabolism in a experimental model of HIE.

Methods:

Six piglets were anesthetised and subjected to a hypoxic-ischemic (HI) insult. Imaging was performed at baseline and two hours after the insult on a 3T MR scanner. For ¹³C studies, [1-¹³C]pyruvate was hyperpolarized in in a commercial polarizer. Following intravenous injection (6 ml, 125 mM isotonic pyruvate solution), rapid interleaved spectroscopic images were acquired using a spectral-spatial spiral imaging sequence. Metabolism of pyruvate to its metabolic products lactate, bicarbonate, and alanine is reported as the accumulated signal of each metabolite proportional to the sum of all three metabolites.

Results:

Hyperpolarized ¹³C MRI was successfully performed. HI resulted in a metabolic shift, with reduction in aerobic metabolism (bicarbonate) (mean (SD); 0.16 (0.04) vs. 0.06 (0.02), p = 0.03) and increase in anaerobic metabolism (lactate) (0.75 (0.04) vs. 0.84 (0.05), p = 0.051). Amino acid synthesis (alanine) (0.10 (0.01) vs. 0.11 (0.04), p = 0.74) remained unchanged.

Conclusion:

To the best of our knowledge, this is the first study to show that hyperpolarized ¹³C MRI can be used in piglets and applied to evaluate early changes in cerebral metabolism after a HI insult. The results provide new insight related to pyruvate metabolism phenotype following a HI insult.