The hippocampus in status epilepticus: demonstration of signal intensity and morphologic changes with sequential fast spin-echo MR imaging.

PURPOSE: To describe imaging findings in the hippocampus in status epilepticus with fast spin-echo (SE) magnetic resonance (MR) imaging.
MATERIALS AND METHODS: Five patients with status epilepticus were examined with fast SE MR imaging, and the findings were correlated with neuropathologic observations of status epilepticus.
RESULTS: One patient with diffuse bilateral hippocampal and amygdalal abnormal hyperintensity died. In three patients with hippocampal abnormal hyperintensity and enlargement, hyperintensity and enlargement, follow-up fast SE MR images depicted decreased hyperintensity and swelling; one patient has remained seizure free at 6 months follow-up; a complex partial seizure disorder developed in two, and repeat images demonstrated hippocampal atrophy.
CONCLUSION: T2-weighted fast SE MR images demonstrate reversible abnormal hyperintensity and swelling of the hippocampus and amygdala in patients with status epilepticus. Sequential fast SE MR imaging allows differentiation of this process from neoplasia and is useful in documentation of post-status epilepticus developments such as mesial temporal sclerosis.