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Objective: To assess accuracy and repeatability of a modified echocardiographic approach to quantify superior vena cava (SVC) flow volume that uses a short-axis view to directly measure SVC area and a suprasternal view to measure flow velocity, both at the level of the right pulmonary artery.Setting: Three tertiary-level neonatal intensive care units.Design: This was a multicentre, prospective, observational study. Accuracy of the traditional and modified approach was first assessed by comparing echo measurements according to both techniques with Phase contrast MRI (PCMRI) assessments, in a cohort of 10 neonates. In a second cohort of 40 neonates, intraobserver scan-rescan repeatability and interobserver analysis-reanalysis repeatability were assessed by repeated SVC flow echo measurements, according to both techniques.Results: The traditional echocardiographic approach to assessment of SVC flow had a moderate agreement with PCMRI (r2 0.259), a scan-rescan intraobserver repeatability index (RI) of 37% (limits of agreement (LOA) -47/+51 mL/kg/min) and an interobserver analysis-reanalysis RI of 31% (LOA -38/+40 mL/kg/min). The modified approach showed a stronger agreement with PCMRI (r2 0.775), an improved intraobserver scan-rescan repeatability (RI 22%, LOA -24/+18 mL/kg/min) and improved interobserver analysis-reanalysis repeatability (RI 18%, LOA -18/+20 mL/kg/min).Conclusions: Echocardiographic assessment of SVC flow volume by tracing area from a short-axis view and measuring velocity-time integral from a suprasternal view offered an improvement in accuracy and repeatability, building on the traditional approach previously described. [ABSTRACT FROM AUTHOR]

Background: Parenteral nutrition is central to the care of very immature infants. Current international recommendations favor higher amino acid intakes and fish oil-containing lipid emulsions. Objective: The aim of this trial was to compare 1) the effects of high [immediate recommended daily intake (Imm-RDI)] and low [incremental introduction of amino acids (Inc-AAs)] parenteral amino acid delivery within 24 h of birth on body composition and 2) the effect of a multicomponent lipid emulsion containing 30% soybean oil, 30% medium-chain triglycerides, 25% olive oil, and 15% fish oil (SMOF) with that of soybean oil (SO)-based lipid emulsion on intrahepatocellular lipid (IHCL) content. Design: We conducted a 2-by-2 factorial, double-blind, multicenter randomized controlled trial. Results: We randomly assigned 168 infants born at,31 wk of gestation. We evaluated outcomes at term in 133 infants. There were no significant differences between Imm-RDI and Inc-AA groups for non-adipose mass [adjusted mean difference: 1.0 g (95% CI: -108, 111 g; P = 0.98)] or between SMOF and SO groups for IHCL [adjusted mean SMOF:SO ratio: 1.1 (95% CI: 0.8, 1.6; P = 0.58]. SMOF does not affect IHCL content. There was a significant interaction (P = 0.05) between the 2 interventions for nonadipose mass. There were no significant interactions between group differences for either primary outcome measure after adjusting for additional confounders. Imm-RDI infants were more likely than Inc-AA infants to have blood urea nitrogen concentrations >7 mmol/L or >10 mmol/L, respectively (75% compared with 49%, P < 0.01; 49% compared with 18%, P < 0.01). Head circumference at term was smaller in the Imm-RDI group [mean difference: 20.8 cm (95% CI: 21.5, -0.1 cm; P = 0.02)]. There were no significant differences in any prespecified secondary outcomes, including adiposity, liver function tests, incidence of conjugated hyperbilirubinemia, weight, length, mortality, and brain volumes. Conclusion: Imm-RDI of parenteral amino acids does not benefit body composition or growth to term and may be harmful. This trial was registered at www.isrctn.com as ISRCTN29665319 and at eudract.ema.europa.eu as EudraCT 2009-016731-34. [ABSTRACT FROM AUTHOR]

Cortical maturation was studied in 65 infants between 27 and 46 wk postconception using structural and diffusion magnetic resonance imaging. Alterations in neural structure and complexity were inferred from changes in mean diffusivity and fractional anisotropy, analyzed by sampling regions of interest and also by a unique whole-cortex mapping approach. Mean diffusivity was higher in gyri than sulci and in frontal compared with occipital lobes, decreasing consistently throughout the study period. Fractional anisotropy declined until 38 wk, with initial values and rates of change higher in gyri, frontal and temporal poles, and parietal cortex; and lower in sulcal, perirolandic, and medial occipital cortex. Neuroanatomical studies and experimental diffusion-anatomic correlations strongly suggested the interpretation that cellular and synaptic complexity and density increased steadily throughout the period, whereas elongation and branching of dendrites orthogonal to cortical columns was later and faster in higher-order association cortex, proceeding rapidly before becoming undetectable after 38 wk. The rate of microstructural maturation correlated locally with cortical growth, and predicted higher neurodevelopmental test scores at 2 y of age. Cortical microstructural development was reduced in a dose-dependent fashion by longer premature exposure to the extrauterine environment, and preterm infants at term-corrected age possessed less mature cortex than term-born infants. The results are compatible with predictions of the tension theory of cortical growth and show that rapidly developing cortical microstructure is vulnerable to the effects of premature birth, suggesting a mechanism for the adverse effects of preterm delivery on cognitive function. [ABSTRACT FROM AUTHOR]

An abstract of the article "Quantification of aortic pulse wave velocity in preterm infants using 4D phase contrast MRI," by Kathryn Broadhouse, Anthony N. Price, Giuliana Durighel, Anna Finnemore, David J. Cox, A.D. Edwards, Joseph V. Hajnal and Alan Groves is presented.

An abstract of the article "Validation of MRI quantification of biventricular cardiac function in term and preterm neonates," by Anna Finnemore, Anthony N. Price, Giuliana Durighel, Kathryn Broadhouse, David J. Cox, and Alan Groves is presented.