Computer interpreted fetal electroencephalogram. II. Patterns in infants who were neurologically abnormal at 1 year of age.

A computer program for pattern recognition of fetal electroencephalogram has been used to analyze the records of nine fetuses, known to be neurologically abnormal at 1 year of age. In 4,913 10 second epochs of adequate FEEG, Low Voltage Irregular (LVI) accounted for 17.8 per cent, Mixed activity (MIX) for 30.5 per cent, High Voltage Slow (HVS) for 18.1 per cent, and Trace Alternant (T/A) for 33.2 per cent of the epochs. The numbers of observed FEEG patterns in these abnormal cases appear to be significantly different from those in 11 normal cases (p less than 0.001)3. Specifically, the relative frequency of LVI was found to be increased in the abnormal cases (p congruent to 0.05). Moreover, LVI was significantly associated with visually interpreted prolonged voltage suppression (p less than 0.025) and lowered one-minute Apgar score (p congruent to 0.025). Using discriminant function analysis for LVI, MIX, HVS, and T/A patterns from FEEG recorded during labor, 10 of 11 infants were correctly classified as being neurologically normal at one year of age and 6 of 9 infants were correctly classified as being neurologically abnormal at 1 year of age. These studies confirm previous associations based on visual analysis of FEEG and suggest that the relative frequencies of FEEG patterns may be useful in the prediction of neurologic outcome 1 year later.