Background Amplitude integrated electroencephalography (aEEG) is a valuable tool for evaluating neonatal encephalopathy and identifying electrographic seizures.

Objective To compare seizure activity and background pattern (BGP) between one-channel and two-channel aEEG recordings in full-term neonates.

Methods The two-channel aEEG recordings (F3-P3; F4-P4) of 34 neonates with seizures were compared with single-channel recordings (P3-P4).

Results All 34 infants with unilateral (n=14), diffuse (n=18) or without (n=2) brain injury had seizure patterns on one-channel and two-channel recordings, with 18% more seizure patterns detected with two-channel recording. In 79% of infants with unilateral injury more seizures were noted on the ipsilateral side compared to the contralateral side. In 39% of the infants with diffuse brain damage more seizures were found with two-channel recordings. A sensitivity of 65% was found when using the automatic seizure detection algorithm. In 4/14 (29%) infants with unilateral injury a more severely affected BGP was seen on the ipsilateral side compared to the BGP on one-channel recording. In infants with diffuse injury differences in BGP pattern were seen in 6–17% of the infants depending on the system used for scoring.

Conclusion Although there were no major differences found between seizure detection with one-channel or two-channel aEEG, in a subgroup of infants with a predominantly unilateral brain lesion, two-channel recording did provide additional information with identification of more seizure patterns on the affected side, sometimes also associated with a difference in BGP. To improve early diagnosis of unilateral lesions and improve seizure detection in these infants, routine use of two-channel recordings is recommended.