Clinical Scorecard: Combining Intraoperative Ultrasound with Depth-Electrode Electrocorticography for Surgical Resection in Epilepsy: A Review of Technical Procedures and Feasibility

At a Glance

Key Highlights

• Approximately 30% of persons with epilepsy have drug-resistant epilepsy requiring surgical intervention.
• Intraoperative ultrasound combined with depth-electrode electrocorticography enhances real-time anatomical and electrophysiological localization of epileptogenic zones.
• This combined approach is particularly useful for deep-seated or sulcal lesions where conventional subdural strip iECoG is limited.

Guideline-Based Recommendations

Diagnosis

• Use high-resolution MRI, PET, and advanced neuroimaging post-processing for pre-surgical evaluation.
• Perform prolonged video-EEG monitoring to establish anatomo-electro-clinical correlations.
• Consider Morphometric Analysis Program (MAP) for suspected focal cortical dysplasia.

Management

• Plan electrode trajectories and resection boundaries using 3D imaging platforms and neuronavigation systems.
• Employ intraoperative depth-electrode iECoG combined with ultrasound to refine resection margins.
• Use conventional subdural strip iECoG as complementary but rely on depth electrodes for deep or sulcal lesions.

Monitoring & Follow-up

• Perform intraoperative panoramic ultrasound scans before dural opening to identify lesion echogenic features.
• Use depth-electrode iECoG recordings intraoperatively to assess epileptogenic activity and guide resection extent.

Risks

• Incomplete resection or inaccurate localization of the epileptogenic zone may lead to postoperative seizure recurrence.
• Limitations of conventional iECoG in deep or sulcal lesions may reduce surgical precision without combined techniques.

Patient & Prescribing Data

Patients with drug-resistant epilepsy and MRI-visible lesions not requiring SEEG investigation

Combined intraoperative ultrasound and depth-electrode iECoG is feasible and reproducible, improving anatomical and electrophysiological guidance for tailored resection.

Clinical Best Practices

• Integrate multidisciplinary presurgical evaluation including epileptologists, neuroradiologists, and neurosurgeons.
• Utilize advanced neuroimaging post-processing tools to enhance lesion localization and surgical planning.
• Employ neuronavigation systems to guide electrode placement and resection boundaries intraoperatively.
• Combine real-time intraoperative ultrasound with depth-electrode iECoG to optimize identification of epileptogenic tissue, especially in deep or sulcal lesions.

References

• Drug-resistant epilepsy prevalence and surgical outcomes
• Intraoperative electrocorticography history and applications
• Role of intraoperative ultrasound in epilepsy surgery
• Advanced neuroimaging post-processing in epilepsy
• Morphometric Analysis Program for focal cortical dysplasia