Late-onset posttraumatic seizures

Estimated incidence of Late-onset posttraumatic seizures 10–13% within 2 yrs after “significant” head trauma (includes LOC > 2mins, GCS < 8 on admission, epidural hematoma…) for all age groups 1) 2) Relative risk: 3.6 times control population. The incidence of severe head injury > moderate > mild 3).

The incidence of early PTS is higher in children than adults, but late seizures are much less frequent in children (in children who have PTS, 94.5% develop them within 24 hrs of the injury 4)). Most patients who have not had a seizure within 3 yrs of penetrating head injury will not develop seizures 5). The risk of late PTS in children does not appear related to the occurrence of early PTS (in adults: only true for mild injuries). Risk of developing late PTS may be higher after repeated head injuries.

1)
McQueen JK, Blackwood DHR, Harris P, et al. Low Risk of Late Posttraumatic Seizures Following Severe Head Injury. J Neurol Neurosurg Psychiatry. 1983; 46:899–904
2)
Young B, Rapp RP, Norton JA, et al. Failure of Prophylactically Administered Phenytoin to Prevent Early Posttraumatic Seizures. J Neurosurg. 1983; 58:231–235
3)
Annegers JF, Grabow JD, Groover RV, et al. Seizures After Head Trauma: A Population Study. Neurology. 1980; 30:683–689
4)
Hahn YS, Fuchs S, Flannery AM, et al. Factors Influencing Posttraumatic Seizures in Children. Neurosurgery. 1988; 22:864–867
5)
Weiss GH, Salazar AM, Vance SC, et al. Predicting Posttraumatic Epilepsy in Penetrating Head Injury. Arch Neurol. 1986; 43:771–773