Topographic mapping of brain potentials in the newborn infant: the establishment of normal values and utility in assessing infants with neurological injury

Aim: To demonstrate that quantitative EEG (qEEG) can be used as a non-invasive measure of brain injury by establishing normative data in term infants and contrasting it with other modalities of brain imaging. Design: qEEG during quiet sleep was performed on 13 healthy full-term infants comprising a normal group and on 10 infants with neurological abnormalities identified on brain imaging studies (abnormal group) at 36–47 wk postconceptional age. Quantitative analysis was performed and topographic maps were produced for each patient. The EEG data from the normal group, after spectral analysis, yielded power data in the delta, theta, alpha, and beta frequency bands and coherence information, which then formed the normative database. qEEG from the infants in the abnormal group was then compared to this normative data. Results: The normal group's mean absolute power in the delta, theta, alpha, and beta bands for all EEG leads combined were 278.48 ± 83.83, 31.71 ± 10.12, 29.20 ± 2.04, and 35.76 ± 11.35 uv2, respectively. The median frequency was 1.49 ± 0.07, 5.45 ± 3.46, 9.74 ± 5.11, and 18.01 ± 3.38 Hz, respectively. The qEEG was abnormal in all 10 study infants, while abnormalities were noted in the clinical EEG in 4 of 10, in the neuroultrasound in 5 of 10, in the CT in one of 6, and in the MRI in 2 of 2 tested. Conclusions: qEEG appears to be a usefd non-invasive method for measuring brain injury as it correlates well with other modalities of brain imaging and, if corroborated by further study, may, in fact, be more sensitive in determining abnormalities in brain function.