Periictal diffusion-weighted imaging in a case of lesional epilepsy

Purpose: Diffusion-weighted MR imaging (DWI) has been used for the early diagnosis of acute ischemic lesions in humans and in animal models of focal status epilepticus. We hypothesized that DWI may be a sensitive, noninvasive tool for the localization of the epileptogenic area during the periictal period. Methods: A periictal DWI study was performed on a 35-year-old patient during focal status epilepticus with repetitive focal motor seizures originating from a lesion in the right frontal lobe. DWI results were analyzed visually and by calculating apparent diffusion coefficient (ADC) maps. Results: Om DWI, a single area of signal increase (decrease in ADC) was found in the region of focal electrocorticographic seizures that was mapped intraoperatively. Conclusions: Ictal/postictal DWI may be a useful technique for seizure localization in patients with lesional epilepsy.