CHARACTERIZATION OF FUNCTIONAL NETWORKS RELEVANT TO THE GENERATION OF EPILEPTIC ACTIVITY
Relevant for Research Area
It is becoming more and more apparent that epilepsy is associated with widespread network alterations that cannot necessarily be well represented by the concept of a restricted epilep-togenic focus. A better understanding of these networks will thus be essential for the devel-opment of effective therapeutic intervention strategies such as targeted stimulation. Yet there is currently no single reliable method to localize epileptogenic foci and associated networks. The NetEpi project employs multimodal measurements using the complementary techniques of EEG and fMRI to achieve the localization (by fMRI) of networks associated with epilepti-form discharges (seen on EEG). Ongoing investigations have revealed widespread patholog-ical networks encompassing distant cerebral regions; some of these regions were shown to be associated with cognitive comorbidities in epilepsy patients. Within individual patients, apparently similar EEG discharges were found to activate highly variable dynamic networks. It is thus clear that any effective focal intervention approach will have to consider the need to interact with the brain as a whole. EEG-fMRI contributes essential information on the locali-zation and topology of the epileptogenic network. Current work focuses on direct applications to the planning and interpretation of electrical stimulation experiments.
We demonstrated a non-invasive neuroimaging technique for the sensitive and accurate characterization of pathological brain networks in epilepsy patients. The technique is further used to monitor epileptic activity propagation and track its long-range effects on healthy brain regions. This work contributes to the planning of focal therapeutic interventions in epilepsy (as well as other neurological diseases) and to monitor the effects of such interventions.
Jacobs J, Stich J, Zahneisen B, Assländer J, Ramantani G, Schulze-Bonhage A, Korinthenberg R, Hennig J, LeVan P (2014) Fast fMRI provides high statistical power in the analysis of epileptic networks. Neuroimage, volume: 88, pp. 282-94.