CLINICAL CORRELATES OF THE FAST AND THE SLOW SPIKE-WAVE ELECTROENCEPHALOGRAM

Abstract

In order to test an hypothesis that slow spike and wave formations may be only the immature form of the 3/sec. dart and dome formation of "petite absence" and to learn more about the meaning of a dysrhythmia that consists of an alternation of wave frequency, a comparison was made of the clinical histories and examinations of 200 patients belonging to each group. The group with the slow pattern contained relatively more males; the patients were younger both when seizures began and at the time of examination, their history contained a greater variety of seizure phenomena and their EEGs more associated abnormalities. The evidence of brain damage that antedated seizures was much greater and the family history of epilepsy was somewhat less in the slow group as contrasted with the fast; and yet, heredity played as great a part in the slow group as in a large unselected group of "genetic" epileptics. Intelligence of the slow group was lower than that of the fast. Slow spike-hump discharges are more diverse in configuration and distribution, more often localized and solitary than dart-dome discharges. The slow form is less often identified with specific clinical symptoms, though in this group of children, 53% had a history of one or more of the petit mal quartette. Astatic (akinetic) falls or simple or massive myoclonic jerks may accompany solitary discharges. Massive jerks were confined to the very young. Of the infants, 55% had this form. Periods of sudden stillness, staring, sagging, small jerkings or mild tonicity, often without full loss of consciousness, may be the clinical correlates of serial discharges. Though less responsive to tridione® or other therapy than the faster variety, control of seizures and even of this peculiar spike-hump dysrhythmia may be possible.