Posttraumatic epilepsy risk factors: One-year prospective study after headinjury

Purpose: Prospective evaluation of risk factors for posttraumatic epilepsy (PTE) by using clinical, EEG, and brain computed tomography (CT) data in fo ur assessments from the head injury (HI) acute phase to 1 year later; and e valuation of the possible epileptogenic role of hemosiderin as shown by bra in magnetic resonance imaging (MRI). Methods: Risk factors for PTE were evaluated by using Kaplan-Meier curves, log-rank test, and the Cox model in 137 consecutively enrolled adult inpati ents. Percentage differences of patients with brain hyperintense and/or hem osiderin areas shown by MRI 1 year after HI were statistically evaluated by univariate tests considering two subgroups [e.g., patients with (PTE) and without (WLS) late seizures]. Results: The PTE subgroup included 18 patients with at least two seizures b etween the second and twelfth months. Kaplan-Meier curves demonstrated that Glasgow Coma Scale low score, early seizures, and single brain CT lesions are PTE risk factors, as is the development of an EEG focus 1 month after H I. No significant percentage difference was found between PTE and WLS patie nts with hemosiderin spots shown by MRI 1 year after HI. Conclusions: the Cox model indicates that, for HI patients with early seizu res and brain CT single temporal or frontal lesions in the acute phase, the PTE risk is 8.58 and 3.43 times higher, respectively, than for those witho ut. An EEG focus 1 month after HI is a risk factor 3.49 times higher than f or patients without such EEG changes. One year after HI, a higher percentag e of PTE than WLS patients had cortical MRI hyperintense areas including he mosiderin.