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. Methods: 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. Results: 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 %).
Conclusion: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.
We report the case of a patient suffering from pharmacotherapy‐resistant bilateral progressive myoclonic epilepsy (PME) showing a beneficial response upon selective deep brain stimulation (DBS) of the substantia nigra pars reticulata. As an individual experimental therapeutic approach, we implanted DBS electrodes in the transitional zone between the subthalamic nucleus (STN) and the substantia nigra pars reticulata (SNr). Electrode placement allowed for a selective stimulation of either the STN, SNr, or both targets. Postoperatively, we observed a moderate subjective and objective improvement in positive and negative myoclonus by high‐frequency DBS of the STN/SNr transitional zone. However, a systematic exploration of different stimulation settings revealed that monopolar stimulation of the substantia nigra alone was more effective than high‐frequency monopolar DBS of either the motor STN (monopolar) or stimulation of both targets (STN/SNr). This observation confirms earlier findings showing that patients with PME benefit from high‐frequency DBS. However, in contrast to previous reports stimulating the STN/SNr transitional zone, our patient showed the most significant effect upon selective stimulation of the SNr. We propose that in patients undergoing DBS for myoclonus, at least one electrode contact should be placed in the SNr allowing for selective monopolar stimulation of this target.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.