Does Stereoelectroencephalography Add Value in Patients with Lesional Epilepsy?

Area of Science:

• Neurosurgery
• Epileptology
• Medical Imaging

Background:

• Stereoelectroencephalography (SEEG) is increasingly used for epileptogenic zone (EZ) localization.
• The utility of SEEG in patients with visible brain lesions is debated.
• This study evaluates SEEG as a presurgical tool for lesional epilepsy.

Purpose of the Study:

• To assess the role and outcomes of SEEG in presurgical evaluation for lesional epilepsy.
• To determine if SEEG influences resection volume and seizure recurrence.
• To identify factors associated with seizure recurrence after epilepsy surgery.

Main Methods:

• Retrospective cohort study of 131 patients with refractory focal epilepsy and lesions undergoing resection (2010-2017).
• Comparison of 71 patients with SEEG followed by resection versus 60 without invasive monitoring.
• Volumetric analysis of resection cavities and statistical analysis of seizure recurrence predictors.

Main Results:

• Mean lesion and resection volumes were smaller in the SEEG group (P=0.009).
• Seizure recurrence was associated with the number of failed antiseizure medications, not resection volume.
• In SEEG patients, more implanted electrodes correlated with seizure recurrence (P=0.005).

Conclusions:

• SEEG presurgical evaluation can optimize resection efficacy and minimize tissue removal in lesional epilepsy.
• SEEG enables surgical consideration for patients with lesional epilepsy who might otherwise be excluded.
• Number of failed medications, not SEEG specifics, was the key predictor of seizure recurrence.