Page 155 - MEGIN Book Of Abstracts - 2023

underwent TCC with pancommissurotomy. The patient seizure propagation as an epidemic process using the
was seizure-free (ILAE Class 3) at one-year follow up susceptible-infected (SI) model on individual brain
with no drop attacks, and significant reduction noted in networks derived from presurgical MEG. We included
other seizure types. 10 patients who had received epilepsy surgery and
for whom the surgery outcome at least one year after
CONCLUSION Endoscopic corpus callosotomy and pan surgery was known. The model parameters were tuned
commissurotomy using the interhemispheric corridor in in order to reproduce the patient-specific seizure
is an elegant and minimally invasive technique best propagation patterns as recorded with invasive EEG. We
suited for appropriately selected children with refrac- defined a personalized search algorithm that combined
tory epilepsy. structural and dynamical information to find resec-
tions that maximally decreased seizure propagation for
Keywords: Anterior commissure, hippocampal com- a given resection size. The optimal resection for each
missure, interhemispheric approach, minimally invasive patient was defined as the smallest resection leading
epilepsy surgery, posterior commissure to at least a 90% reduction in seizure propagation. The
individualized model reproduced the basic aspects of
Neurology India (2022), Vol. 70, No. 1 (35263855) (1 seizure propagation for 9 out of 10 patients when using
citation) the resection area as the origin of epidemic spreading,
and for 10 out of 10 patients with an alternative defini-
tion of the seed region. We found that, for 7 patients,
Epidemic models characterize seizure propagation the optimal resection was smaller than the resection
and the effects of epilepsy surgery in individualized area, and for 4 patients we also found that a resection
brain networks based on MEG and invasive EEG smaller than the resection area could lead to a 100%
recordings (2022) decrease in propagation. Moreover, for two cases these
alternative resections included nodes outside the re-
Millán, Ana P; van Straaten, Elisabeth C W; Stam, section area. Epidemic spreading models fitted with pa-
Cornelis J; Nissen, Ida A; Idema, Sander; Baayen, tient specific data can capture the fundamental aspects
Johannes C; Van Mieghem, Piet; Hillebrand, Arjan of clinically observed seizure propagation, and can be
used to test virtual resections in silico. Combined with
Department of Clinical Neurophysiology and MEG Cen- optimization algorithms, smaller or alternative resec-
ter, Amsterdam Neuroscience, Vrije Universiteit Amster- tion strategies, that are individually targeted for each
dam, Amsterdam UMC, Amsterdam, The Netherlands. patient, can be determined with the ultimate goal to
[email protected]; Department of Neuro- improve surgery outcome. MEG-based networks can
surgery, Amsterdam Neuroscience, Vrije Universiteit Am- provide a good approximation of structural connectiv-
sterdam, Amsterdam UMC, Amsterdam, The Netherlands; ity for computational models of seizure propagation,
Faculty of Electrical Engineering, Mathematics and Computer and facilitate their clinical use.
Science, Delft University of Technology, Delft, The Netherlands
Scientific reports (2022), Vol. 12, No. 1 (35260657) (0
ABSTRACT Epilepsy surgery is the treatment of citations)
choice for drug-resistant epilepsy patients. However,
seizure-freedom is currently achieved in only 2/3 of the
patients after surgery. In this study we have developed Interictal epileptiform discharges in focal epilepsy
an individualized computational model based on MEG are preceded by increase in low-frequency
brain networks to explore seizure propagation and oscillations (2022)
the efficacy of different virtual resections. Eventually,
the goal is to obtain individualized models to optimize Westin, Karin; Cooray, Gerald; Beniczky, Sándor;
resection strategy and outcome. We have modelled Lundqvist, Daniel

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