Effective connectivity in long-term EEG monitoring in preterm infants.
OBJECTIVE
Electroencephalogram (EEG) is commonly used to monitor brain activity in preterm neonates. Long-term EEG is used to predict outcomes by total band power. This study reports effective connectivity analyses in the fronto-parietal network in preterm infants.


METHODS
Directed transfer functions (DTFs) were used in fully automated calculations of effective connectivity. Continuous eight-channel EEG recordings were performed for three full days starting at a median of 5.3h (2.5-11.2h) after birth. Analyses were performed using the channels Fp1, Fp2, P3 and P4. DTF were calculated every second in every connection and channel for all frequencies from 1 Hz to 30 Hz. The median connectivity was used in the connectivity assessment.


RESULTS
Parieto-frontal connectivity was significantly higher (0.22) than fronto-parietal connectivity (0.05). There was a significant decrease in parieto-frontal connectivity between day one (0.18) and three. Conversely, there was a significant increase in fronto-parietal connectivity from day one to day three (0.07).


CONCLUSIONS
Significant changes are seen in connectivity from day one to three, but there were no certain connectivity differences between gestational ages.


CONCLUSIONS
A rapid change in fronto-parietal connectivity was seen from day one to three which may indicate fast postpartum maturation.
University of Oslo, Faculty of Medicine, Department of Paediatrics, Oslo University Hospital Ullevaal, PB 4956, 0424 Oslo, Norway.
E M
EM
Schumacher
University of Oslo, Faculty of Medicine, Department of Neonatology, Oslo University Hospital Ullevaal, PB 4956, 0424 Oslo, Norway.
T A
TA
Stiris
Clinical Neurophysiological Section, Department of Neurosurgery, Oslo University Hospital, PB 4950, 0424 Oslo, Norway. Electronic address: pall@ous-hf.no.
P G
PG
Larsson
D001921:Brain / Q000502:physiology*; D004569:Electroencephalography / Q000379:methods / Q000639:trends*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D008297:Male; D009434:Neural Pathways / Q000502:physiology; D013997:Time Factors
Connectivity; Default mode network; Developmental outcome; EEG; Maturation; Preterm