Absent posterior alpha rhythm: An indirect indicator of seizure disorder?

Abstract

Hypothesis:Absence of normal posterior alpha rhythm is an indirect indicator of seizure disorder.Materials and Methods:Study group consists of 116 child and adolescent patients in the age range of 5-17 years, with established history of seizure disorder. Follow-up cases of seizure disorder formed first comparison group, patients with a history of pseudo-seizures formed second comparison group and patients with a history of headache formed the third comparison group.Results:In significant 48.3% (56) patients within the study group there was no visible alpha rhythm. Whereas, this absent alpha rhythm criteria was seen in only 11.2% (4) patients in first and 15% (8) patients in second and in only 6.1% (2) patients in third comparison groups.Discussion:Absent alpha rhythm- a criterion seems to have a certain amount of specificity for electroencephalograms (EEGs) with seizure disorder patients. Presence of seizure activity and absence of alpha activity in EEG significantly correlated to each other (Significant at < 0.01 level). Absent alpha rhythm appears to be a state marker rather than a trait marker of seizure disorder.