State of the art of magnetic resonance (MR) in neonatal hypoxic-ischemic encephalopathy.

Magnetic resonance (MR) has begun to play an important role in neonatal neurology. Several MRI techniques have been applied to the diagnosis of hypoxic ischemic encephalopathy. Cerebral perfusion examined by intravoxel incoherent motion, a non-invasive tool, seems to be opening new inroads for detecting variations (neurophysiological modifications) in cerebral flows during hypoxic ischemic encephalopathy. MR spectroscopy allows identification of specific biochemical alteration of spectra patterns at various moments of hypoxic ischemic distress, including: (1) primary expression of metabolic disorders induced by the lack of blood and O2, revealed by a peak of the water-suppressed H1 spectrum, the earliest and most persistent-marker; (2) a secondary marker for the establishment of permanent lesions of anoxic-ischemic origin revealed that variations of the phosphocreatine/inorganic phosphorous index in the P31 spectrum are of diagnostic and prognostic significance in this phase. In relation to different neuropathological, structural lesions, MRI becomes particularly important in diagnosing the acute phase of cerebral edema and the different types of infarct. MRI is especially fruitful in monitoring the evolution of the lesion, providing an evaluation of myelinization, and defining the neuropathological outlook. Spectroscopic studies on human neonates have helped establish the therapeutic effects of mannitol in cerebral metabolism. MR studies on neonate animals seem to open new therapeutic prospect for CA antagonists.