Sequential changes of brain CT and MRI after febrile status epilepticus in a 6-year-old girl.

Brain CT or MRI occasionally shows transient or permanent changes in the brain after status epilepticus (SE). The mechanism for these changes has not been well elucidated. We performed repeated imaging studies on a patient with febrile SE characterized by right hemiconvulsion. CT showed transient mild edema on both hemispheres immediately after the cessation of SE. The edema improved the next day. But aphasia and right hemiparesis were observed. On day 17, CT revealed edema on left hemisphere and MRI showed a high signal intensity in cortex and subcortical white matter of the left hemisphere on T2-weighted images. Although right hemiparesis and aphasia were improved, severe atrophy of the left hemisphere was noted on CT and MRI. The results suggest that brain edema observed in several days after SE but not edema observed immediately after the cessation of SE is more pathological for the permanent brain damage. Possible mechanisms of the initial brain edema and the second edema preceded severe atrophy in left hemisphere were discussed.