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