A combined a-EEG and MR spectroscopy study in term newborns with hypoxic-ischemic encephalopathy

Brain damage following a perinatal hypoxic-ischemic (HI) insult has been documented by different diagnostic techniques. The aim of the present study was to relate a-EEG time course during the first 24h of life to brain metabolic changes detected by proton MR spectroscopy ((1)H-MRS) at 7-10days of life and to evaluate their correlation with outcome.

Thirty-two patients with any grade HI encephalopathy were studied. Thirty-one out of 32 patients survived and underwent (1)H-MRS examination at 7-10days of life; a-EEG was recorded during the first 24h of life in 27/32 newborns; 26 patients underwent both examinations. Griffiths test, evaluation of motor skills, visual and hearing function were performed at regular intervals until the age of 2years.

a-EEG at 6, 12 and 24h of life showed a significant correlation with outcome. N-acetyl-aspartate/creatine (Cr), Lactate/Cr and myo-inositol differed significantly between patients with normal or poor outcome. a-EEG time course during the first 24h of life showed improvement in newborns with normal (1)H-MRS and good outcome and a deterioration in those with abnormal (1)H-MRS and poor outcome.

a-EEG time course may be able to document the severity and the evolution of the cerebral damage following an HI event. a-EEG is related to the severity of cerebral injury as defined by (1)H-MRS and both examinations showed a good correlation with outcome. These data, obtained in non-cooled infants, may represent reference data for future investigations in cooled infants.