Brain damage caused by status epilepticus: A prospective MRI study

Background: Status epilepticus (SE) is a severe neurological condition that might lead to long-term consequences such as neuronal death. This study investigated whether SE leads to brain volume loss by characterizing the dynamic of peri-ictal MRI abnormalities (PMA) through follow-up MRIs and assessing whether SE duration and specific outcome characteristics are associated with brain atrophy. Methods: A prospective single-center cohort study enrolled 590 adult patients with definitive or possible SE. MRI in an acute setting was performed in 353/590 (60 %) patients. Follow-up MRIs at one week and one month were conducted to assess the reversibility of PMA. Measurements of diffuse brain volume were performed by employing a voxel-based morphometry with FreeSurfer, comparing an initial MRI with a follow-up test done four weeks after the initial one. The study analyzed the correlation between brain volume loss, SE duration, and clinical outcomes. Results: PMA were observed in 156/353 (44 %) patients in at least one MRI sequence. In 44/83 (53 %) patients, PMA were reversible in one week. PMA persisted in 39/83 (47 %) patients. A second follow-up MRI was performed four weeks after the initial MRI in 33/39 (85 %) patients. In 14/33 (42 %), the MRI showed signs of focal atrophy, mostly in hippocampus. Volumetric analysis performed in patients who underwent two follow-up MRIs, indicated that 85 % of patients (28/33) had a decreased diffuse brain volume, with a median volume reduction of 16 %. A moderate negative correlation was found between diffuse brain volume and SE duration (Spearman correlation: -0.57) as well as hospitalization length (Spearman correlation: -0.60). This indicates that longer SE duration and extended hospitalization were associated with a greater brain volume loss. Conclusion: In this prospective study, a proportion of patients displayed cerebral volume loss following a SE. These patients had longer duration and worse outcome of SE. However, the findings should be interpreted with caution due to several limitations, including the lack of consideration for underlying etiologies that may contribute to volume loss.