Scarcity of minor EEG abnormalities during the first two years of life.
This EEG study is based upon pediatric material (0--5 years) of an institution for handicapped children (983 records, 798 children) and a teaching hospital (956 records, 643 children). In records read as abnormal, stress was laid on the degree of abnormality. A grading system of abnormality was consistently employed and facilitated the quantification of EEG abnormalities. The following grades were used: minimally abnormal, slightly abnormal, moderately abnormal, abnormal and very abnormal. The age of the children was broken down as follows: 0--3 months, 4--6, 7--9, 10--12, 13--15, 16--18, 19--21, 22--24, 25--30, 31--36, 37--42, 43--48, 49--54 and 55--60 months. It was found that minor EEG abnormalities (minimally to moderately abnormal) were scarce in the age range from 0--21 months. The rariety of such minor abnormalities proved to be statistically highly significant. A breakdown into epileptic and non-epileptic conditions did not yield much additional information. This could be due to a limited number of EEG responses (with lack of fine intermediate nuances of abnormality) to cerebral impairment below the age of 21 months. It is also possible, however, that further progress in the field of clinical-electrical correlations can demonstrate the mildly abnormal character of certain patterns (hitherto regarded as normal).
D000367:Age Factors; D001927:Brain Diseases / Q000175:diagnosis*; D002675:Child, Preschool; D004569:Electroencephalography; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D012189:Retrospective Studies