Computer Assisted Planning For The Insertion Of Stereoelectroencephalography Electrodes For The Investigation Of Drug Resistant Focal Epilepsy: An External Validation Study

摘要

BackgroundOne third of patients with focal epilepsy are drug refractory and surgery may provide a cure. Seizure free outcome following surgery is dependent on the correct identification and resection of the epileptogenic zone. In patients with no visible MRI abnormality, or when pre-surgical evaluation yields discordant data, invasive Stereoelectroencephalography (SEEG) recordings may be necessary. SEEG is a procedure in which multiple electrodes are stereotactically placed in key targets within the brain to record interictal and ictal electrophysiological activity. Correlating this activity with the seizure semiology allows identification of the seizure onset zone and key structures within the ictal network. The main risk of SEEG electrode placement is haemorrhage, which occurs in 1% of patients. Planning safe SEEG electrodes requires meticulous adherence to the following constraints: 1) maximise distance from cerebral vasculature, 2) avoid crossing sulcal pial boundaries (sulci), 3) maximize grey matter sampling, 4) minimise electrode length, 5) drilling angle orthogonal to skull and 6) avoid critical neurological structures. We provide a validation of EpiNav™ Strategy and Planning™, a multimodal platform that allows automated computer-assisted planning (CAP) of SEEG electrodes by user defined regions of interest.