Anoxia-Ischemia, Brain

Neonatal anoxia-ischemia causes significant neurodevelopmental disorders. In this study the investigators want to better understand the interactions between the nervous and the hemodynamic cerebral systems during the adaptation of the neonate to ectopic life just after birth. Birth is an at risk situation of neonatal anoxic ischemia and the lack of objective criteria for cerebral tissue oxygenation has consequences on neuronal activity. Ph cord analysis is inadequate and only indirectly reflects the state of cerebral oxygenation. Both neuronal and vascular systems are part of the same functional entity and the analysis of their interactions is likely to reveal some early malfunctions of these networks. In this study, the investigators want to develop a multi-scale, multimodal approach that allows simultaneous interrogation of both neuronal and vascular compartments during the 15 minutes after delivery. The investigators will record, with the aid of a single sensor placed on the scalp of the child, the electroencephalogram and the cerebral tissue oxygenation. The investigators will measure interactions by means of correlation analysis between both signals.

Standard predictors of outcome after cardiac arrest (CA) have substantial limitations in terms of reliability and generalizability. By providing brain structural connectivity maps, or connectomes, advanced MRI techniques, operating through high-strength magnetic field (HF; 1.5 to 3-T), have precisely revealed white and grey brain matter damages induced by CA, and have demonstrated the high sensitivity and specificity of these indicators for predicting neurological outcome after CA. However, HF MRI requires rigid safety precautions, highly trained technicians and patient transport to dedicated hospital imaging suites, hindering the implementation of these promising neuroimaging techniques in the setting of critical illness. Interestingly, a recent report demonstrates the capability of a proof-of-concept very low-field (VLF; 0.064-T) mobile MRI to obtain neuroimaging at the bedside in critically ill patients. Nevertheless, the spatial resolution of VLF-MRI seems low and there is no available evidence about the use of VLF-MRI to extract highly needed new predictors of neurological recovery based on critical brain structural connectomes. The CUBE project holds the promise of providing a radical paradigm shift in the field of neuroprognostication of anoxic coma patients. The current proposal is a "proof-of concept" study which aims to compare for the first time, HF, VLF and enhanced VLF (recon-VLF) structural connectomes from anoxic coma patients and healthy subjects across the time (3 paired HF and VLF brain scan across the first two weeks after CA). To obtain recon-VLF data, the Investigators will use an ensemble of ground-breaking methods to increase the native spatial resolution of VLF-MRI data. The whole brain imaging dataset will be used to prepare future neuroprognostication studies based on fully bedside assessment of brain structural integrity after CA.