Clinical Characteristics of Grand mal (Generalized Tonic‐Clonic Convulsion): A Contribution to the Ictal Symptomatology

摘要

Abstract:The purpose of this study is to evaluate the possibilities of whether the long‐ranged clinical course of generalized tonic‐clonic convulsions (GTC) and the ictal symptomatology were modified in accordance with the patho‐etiological backgrounds of epilepsies as reflected by the International Classification (1970). The study consisted of two parts: 1) A transsectional survey of 1,896 patients dealing with the onset age and seizure frequency of GTCs, the time of occurrence in the sleeping‐waking cycle, the GTC monosymptomatic course in comparison with that of combined seizures and the seizure prognosis as a result of drug response. It was found that the mode of occurrence and the clinical course unequivocally differed in accordance with the type of epilepsies: primary (idiopathic) generalized, secondary (symptomatic) generalized and partial. 2) An analysis of the ictal symptomatology of GTC by the use of a simultaneous recording was conducted on 42 GTCs of 42 patients who were carefully selected based on the criteria the authors defined. The clinical features of the convulsive phenomena and concurrent seizure discharges enabled us to subclassify them into three groups; typical, atypical and secondarily generalized. GTCs in patients with partial epilepsies were, of course, all found in the secondarily generalized group while GTCs in patients with primary generalized epilepsies were typical. It was emphasized that atypical GTCs were found in patients either with the Lennox‐Gastaut syndrome or with other secondary generalized epilepsies, whereas there was no atypical GTC in patients either with primary generalized or partial epilepsies. The ictal EEG expressions were found crucial in differentiating these three groups in addition to the symmetry and asymmetry of GTCs. It has been discussed that such distinctly different ictal expressions of GTCs may reflect the pathoetiological backgrounds of epilepsies: primary (centrencephalic), secondary (diffuse or multifocal) and partial (localization‐relate