Clinical outcome after complete or partial cortical resection for intractable epilepsy

Area of Science:

• Neurosurgery
• Epileptology
• Clinical Neuroscience

Background:

• Epilepsy surgery aims to improve seizure control by resecting epileptogenic zones.
• Defining the "completeness" of resection is crucial for predicting surgical success.
• Current definitions often rely on post-operative imaging, which may not fully capture functional resection margins.

Purpose of the Study:

• To evaluate the definition of "completeness" of epilepsy surgery resection.
• To determine the impact of complete resection of epileptogenic zones on clinical outcomes.
• To assess the correlation between EEG-defined resection completeness and surgical success.

Main Methods:

• Analysis of a series of epilepsy surgery patients.
• Utilizing chronic scalp and subdural electroencephalography (EEG) recordings.
• Correlating EEG findings of ictal and interictal epileptiform discharges with clinical outcomes.

Main Results:

• Complete resection of all cortical areas exhibiting epileptiform discharges correlated with good clinical outcomes.
• Incomplete resection of these areas resulted in significantly lower rates of good outcomes.
• This correlation remained consistent irrespective of CT-detected structural lesions or post-resection electrocorticography findings.

Conclusions:

• Completeness of resection, defined by prolonged extraoperative EEG, is a critical factor for successful epilepsy surgery.
• EEG-based assessment of epileptogenic zone removal provides a reliable measure of resection completeness.
• This approach offers a functional definition of resection success beyond structural imaging.