Acute hypoxic encephalopathy in the full-term newborn: correlation between Magnetic Resonance Spectroscopy and neurological evaluation at short and long term

PURPOSE: To determine which brain metabolite ratios have the strongest correlation with poor neurological outcome in newborns with perinatal asphyxia, whether the correlation is stronger with basal ganglia (BG) and whether a combined approach using Magnetic Resonance Imaging (MRI) and Magnetic Resonance Spectroscopy (MRS) can be used to evaluate the severity of neonatal asphyxia. MATERIALS AND METHODS: Twenty newborns with perinatal asphyxia were studied within the first week from the hypoxic insult with MRI and MRS. The MRS variables were compared with the assessment of general movements (GMs). The brain metabolite levels measured by MRS were N-acetylaspartate (NAA), creatine (Cr), choline (Cho) and lactate and the ratios NAA to Cr, Lac to Cr, Cho to Cr, mI to Cr. RESULTS: High lactate levels and low NAA levels were found in the newborns with the worst outcome; the levels in newborns with good outcome were within normal limits. CONCLUSIONS: Correlations between NAA/Cr and Lac/Cr ratios, general movements and outcome at 6 months are stronger in the basal ganglia regions than in the frontal border zone. The presence or absence of lactate may indicate the severity of the brain insult and the combination of MRS, MRI and evaluation of general movements may assist in localising and predicting a long-term brain injury.