Electroencephalographic dysmaturity in preterm infants: a prognostic tool in the early postnatal period.

The aim of the study was to assess the prognostic value of maturational abnormalities in the electroencephalogram (EEG) of preterm infants. 63 subjects (mean gestational age: 32.7 weeks; range 28-34) were submitted to EEG recording within the first two weeks of life and subsequently followed up until at least 12 months of corrected age. Maturational features of background EEG were analysed and the occurrence of different degrees of maturational anomalies ("dysmaturity") was scored, according to standardised criteria. The results were compared to neurological outcome and to cranial ultrasound (US) findings. EEG maturational features significantly related to the outcome. When the EEG background activity was normal all but one patient showed a favourable outcome; the incidence of neurological sequelae became higher according to the degree of dysmaturity detected. However, some infants had a normal evolution, despite severe EEG dysmaturity in the early postnatal period. The correlation between EEG and US findings was low, although US also significantly related to the outcome. Background EEG maturational features seem to be a reliable prognostic tool in the early postnatal period of preterm infants, complementary to serial US scans.