Intra-operative electrocorticography in lesional epilepsy

Area of Science:

• Neurosurgery
• Epileptology
• Clinical Neurophysiology

Background:

• Intractable epilepsy necessitates surgical intervention to improve patient quality of life.
• Intra-operative electrocorticography (ECoG) is a critical tool for precisely identifying and resecting epileptogenic zones.
• Preoperative evaluations like SPECT and PET can supplement ECoG in complex cases.

Purpose of the Study:

• To evaluate the utility of intra-operative electrocorticography (ECoG) in guiding epilepsy surgery.
• To assess the correlation between ECoG findings and clinical outcomes in patients undergoing epilepsy surgery.
• To determine the predictive value of ECoG for surgical success in intractable epilepsies.

Main Methods:

• A retrospective analysis of 157 patients who underwent epilepsy surgery between 2000 and 2008.
• Pre- and post-resection ECoG recordings were performed in all cases, with some patients having serial recordings.
• Clinical outcomes were assessed at long-term follow-up (mean 18.2 months) using the Engel classification.

Main Results:

• 82% of patients showed ECoG improvement, with further improvements noted in serial post-operative recordings.
• 73% of patients achieved good clinical outcomes (Engel I and II).
• Post-operative ECoG improvement demonstrated a significant correlation with favorable clinical outcomes (Sensitivity: 100%, Specificity: 68.3%, PPV: 89.9%, NPV: 100%).

Conclusions:

• Intra-operative ECoG is a valuable tool for delineating the epileptogenic zone and evaluating resection completeness in epilepsy surgery.
• ECoG findings correlate significantly with clinical outcomes, providing a reliable indicator of surgical success.
• The study highlights the importance of ECoG in optimizing surgical strategies and predicting seizure control in patients with intractable epilepsy.