Safety profile of subdural and depth electrode implantations in invasive EEG exploration of drug-resistant focal epilepsy

Julia Männlin; Victoria San Antonio-Arce; Peter Christoph Reinacher; Christian Scheiwe; Mukesch Johannes Shah; Horst Urbach; Andreas Schulze-Bonhage

doi:10.1016/j.seizure.2023.05.022

Safety profile of subdural and depth electrode implantations in invasive EEG exploration of drug-resistant focal epilepsy

Seizure. 2023 Aug:110:21-27. doi: 10.1016/j.seizure.2023.05.022. Epub 2023 Jun 3.

Authors

Julia Männlin¹, Victoria San Antonio-Arce², Peter Christoph Reinacher³, Christian Scheiwe⁴, Mukesch Johannes Shah⁵, Horst Urbach⁶, Andreas Schulze-Bonhage⁷

Affiliations

¹ Freiburg Epilepsy Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, Freiburg im Breisgau 79106, Germany. Electronic address: juliamaennlin@t-online.de.
² Freiburg Epilepsy Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, Freiburg im Breisgau 79106, Germany; Member of the European Reference Network for Rare and Complex Epilepsies EpiCARE, Germany.
³ Department of Stereotactic and Functional Neurosurgery, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, Freiburg im Breisgau 79106, Germany; Fraunhofer Institute for Laser Technology (ILT), Aachen, Germany.
⁴ Department of Neurosurgery, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, Freiburg im Breisgau 79106, Germany.
⁵ Department of Stereotactic and Functional Neurosurgery, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, Freiburg im Breisgau 79106, Germany.
⁶ Department of Neuroradiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, Freiburg im Breisgau 79106, Germany.
⁷ Freiburg Epilepsy Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Str. 64, Freiburg im Breisgau 79106, Germany; Member of the European Reference Network for Rare and Complex Epilepsies EpiCARE, Germany. Electronic address: andreas.schulze-bonhage@uniklinik-freiburg.de.

PMID: 37302157
DOI: 10.1016/j.seizure.2023.05.022

Abstract

Purpose: To analyze the safety profile of subdural and depth electrode implantation in a large monocentric cohort of patients of all ages undergoing intracranial EEG exploration because of drug resistant focal epilepsy diagnosed and implanted by a constant team of epileptologists and neurosurgeons.

Methods: We retrospectively analyzed data from 452 implantations in 420 patients undergoing invasive presurgical evaluation at the Freiburg Epilepsy Center from 1999 to 2019 (n = 160 subdural electrodes, n = 156 depth electrodes and n = 136 combination of both approaches). Complications were classified as hemorrhage with or without clinical manifestations, infection-associated and other complications. Furthermore, possible risk factors (age, duration of invasive monitoring, number of electrode contacts used) and changes in complication rates during the study period were analyzed.

Results: The most frequent complications in both implantation groups were hemorrhages. Subdural electrode explorations caused significantly more symptomatic hemorrhages and required more operative interventions (SDE 9.9%, DE 0.3%, p < 0.05). Hemorrhage risk was higher for grids with 64 contacts than for smaller grids (p < 0.05). The infection rate was very low (0,2%). A transient neurological deficit occurred in 8.8% of all implantations and persisted for at least 3 months in 1.3%. Transient, but not persistent neurological deficits were more common in patients with implanted subdural electrodes than in the depth electrode group.

Conclusion: The use of subdural electrodes was associated with a higher risk of hemorrhage and transient neurological symptoms. However persistent deficits were rare with either approach, demonstrating that intracranial investigations using either subdural electrodes or depth electrodes carry acceptable risks in patients with drug-resistant focal epilepsy.

Keywords: Complication; EEG; Electrode; Epilepsy; SEEG; Subdural EEG; intracranial recordings.

MeSH terms

Drug Resistant Epilepsy* / diagnosis
Electrodes, Implanted / adverse effects
Electroencephalography / adverse effects
Epilepsies, Partial* / diagnosis
Humans
Neurosurgical Procedures / adverse effects
Postoperative Complications / etiology
Retrospective Studies