Usefulness of magnetic resonance imaging in differentiation between status epilepticus and acute ischemic stroke

Background: Status epilepticus, characterized by the temporal neurological deficits, often mimics acute ischemic stroke. We investigated the usefulness of magnetic resonance imaging for differentiation of status epilepticus from acute ischemic stroke. Methods: A retrospective case series of patients with status epilepticus who underwent brain magnetic resonance imaging. For comparative analysis, a series of patients with acute ischemic stroke caused by unilateral middle cerebral artery occlusion was used. Results: Ten patients (4 females and 6 males) with status epilepticus who underwent brain magnetic resonance imaging were included. The median age at diagnosis was 82 years (age range, 70-90 years). In all ten patients, hyperintensities in diffusion-weighted imaging with decreased apparent diffusion coefficient values, decreased venous intensity in susceptibility-weighted imaging, and hyperperfusion in arterial spin labeling perfusion were detected in the cortex of the affected side. Four patients showed an additional diffusion restriction in the thalamus. The apparent diffusion coefficient value of the lesional area was 13.1% less than the contralateral, which was less than one-third as acute ischemic stroke. Status epilepticus patients showed no change in medullary venous intensity of the affected area in susceptibility-weighted imaging, whereas acute ischemic stroke patients showed increased cortical and medullary venous intensity in affected hemisphere. Seven of eight patients with status epilepticus who underwent magnetic resonance angiography showed dilation of the cerebral arteries in the ipsilateral side. Conclusions: The combined use of diffusion-weighted imaging, susceptibility-weighted imaging, and arterial spin labeling perfusion may help accurate and prompt diagnosis of status epilepticus.