Outcome following surgery for insulo-opercular epilepsies

Area of Science:

• Neurosurgery
• Epileptology
• Clinical Neurology

Background:

• Medically refractory epilepsy originating from the insulo-opercular region presents unique surgical challenges.
• Accurate localization and surgical intervention are critical for improving seizure control in these patients.

Purpose of the Study:

• To evaluate the clinical outcomes of resective or ablative surgery for insulo-opercular epilepsy foci.
• To assess seizure freedom rates and neurological complications following insulo-opercular epilepsy surgery.

Main Methods:

• A review of a prospectively maintained database of epilepsy surgery patients with a minimum 12-month follow-up.
• Analysis of presurgical data, stereo-EEG (SEEG) findings, surgical techniques (resection/ablation), pathology, and outcomes.
• Exclusion of patients who underwent combined insulo-opercular and temporal lobectomy.

Main Results:

• Of 24 patients undergoing exclusive insulo-opercular surgery, 75% achieved Engel class I outcome (seizure freedom).
• Immediate postoperative deficits occurred in 42%, persisting in 12.5% long-term.
• Seizure freedom rates were comparable between MRI-positive and MRI-negative cases.

Conclusions:

• Insulo-opercular epilepsy surgery is less common and technically demanding, often requiring SEEG for localization.
• High rates of seizure freedom are achievable, but morbidity is higher compared to other focal epilepsies.
• Development of minimally invasive surgical strategies is paramount for this patient subgroup.