Mutual cortico-thalamic interactions are assumed to be the basis for sustained ictal activity during status epilepticus. We aimed to investigate thalamic involvement during focal status epilepticus through the analysis of ictal diffusion-weighted MR-imaging.
We retrospectively analyzed a cohort of 62 patients who received an MRI scan during an episode of focal onset status epilepticus in our center between 2001 and 2018.
Thalamic diffusion restrictions during focal status epilepticus were found in 29 of 62 cases (46.8 %). As the most frequent localization, the medial pulvinar was affected in 22 cases (75.9 %). Temporal status epilepticus was associated with thalamic DWI-findings (20/33, 60.6 %), in particular in the medial pulvinar (18/33, 54.5 %). To the contrary, the medial pulvinar was less frequently involved in parietal (3/11, 27.3 %) and only rarely in frontal status epilepticus (1/15, 6.7 %).
The medial pulvinar appears to be a frequently involved subcortical relay for maintenance of ictal activity in temporal onset focal status epilepticus. Our findings provide possible novel insights regarding the interpretation of thalamic DWI restrictions in patients with unclear neurological conditions.