[Epileptic manifestations following head injury (author's transl)]

Abstract

An analysis is presented of the findings in a group of 300 patients with head injury, aged 15 years or over at the time of the accident, who subsequently developed epileptic manifestations. Early fits (including one case of immediate onset) were found in 33% of the cases (99 patients). In contrast to post-traumatic late epilepsy (PTE), which is a manifestation of a static process, early fits are triggered off by a dynamic process (brain oedema, haemorrhage) and are a sign of cerebral irritation, but do not represent a true form of epilepsy. Early fits are related to the acute traumatic state; the time limit is flexible, but lies in the region of 4 weeks following injury. Conversion of early fits to PTE (with or without a latent interval) occurred in 72% of the cases. This percentage is higher than the average incidence quoted in the literature and presumably arises partly from the selection criteria applied in this study. The time of appearance of early fits following injury is one factor which determines the prognosis. Fits appearing on the first day carry a relatively favourable prognosis and do not proceed to PTE in 41% of the cases, whereas this percentage shrinks to 15% in the case of fits appearing from the second week onwards. Early fits are an isolated occurrence in one third of the cases; progression to PTE is less frequent in these patients than following frequent, repeated convulsions. Furthermore, the incidence of early fits is dependent, to a large extent, on traumatological and clinical factors: the combination of unconsciousness of over three hours' duration, neurological signs referable to the central nervous system, persistent organic psychotic syndrome and intracranial bleeding leads to a significantly higher incidence of early fits than unconsciousness of less than three hours' duration and absence of neurological signs in patients who, moreover, do not display features of the psychotic syndrome, and shows a greater tendency to early fits even than the combination of depressed fracture of the skull with penetration of the dura. Should, however, early fits occur in spite of a favourable assessment of the traumatological factors involved, then progression to PTE occurs in a higher percentage of such cases than in patients displaying signs of a serious import following injury. The transition to PTE is markedly higher following diffuse cerebral contusion (75% of cases) than in cases displaying signs of local contusion....