Speaker Biography

Dr. Hanin Algethami

Title: MEG in Pre-Surgical Evaluation in Patient with Epilepsy.

Biography:

Epilepsy and electrophysiology fellow at King Fahad Medical City, Riyadh, KSA. Completed pediatric neurology training residency program at King Abdullah Specialized Children hospital, King Abdul-Aziz Medical city, Riyadh, KSA.

Abstract:

Background:

Epilepsy is a highly prevalent, serious neurological disease, characterized by recurrent unprovoked and often debilitating seizures. Between 30% and 40% of patients with epilepsy are resistant to antiepileptic drugs. Epilepsy surgery is the current gold standard treatment for such patients.

MEG is an advanced noninvasive neurophysiology imaging technique that is often used in the course of the presurgical evaluation of patients to estimate epileptic foci. The only MEG system in Saudi Arabia is installed in KFMC. However, no systematic analysis has been conducted yet exploring its yield, potential or clinical value in epilepsy surgeries in KFMC.

Methods:

Current project involves a retrospective study of patients with drug-resistant focal epilepsy, who underwent: (i) presurgical MEG and (ii) epilepsy surgery.  Around 50 such patients have been identified from KFMC electronic medical records over an eight-year period (2011-2019). Here we present preliminary results from 18 patients.

Objectives:

The main objective of the current study is to assess the yield, clinical utility and added value of MEG at KFMC in presurgical evaluation of patients with epilepsy, as well as clearly define its clinical indications.

Results:

Gender (Male / Female)

11 (61.1%) / 7 (38.8%)

Handedness (Right / Left / Ambidextrous)

16 (88.8%) / 1 (5.5%) / 1 (5.5%)

Age of onset (Mean / SD / Range)

10.6 / 8.04 / 1-26 

Age of evaluation (Mean / SD / Range)

24.6 / 11.1 / 4-39  

Seizure duration

14 / 9.9 / 2-29  

MRI findings

FCD: 7 (38.8%) Normal: 2 (11.1%) AVM: 1 (5.5%) MTS: 8 (44.4%)

Post-op follow-up (Mean / SD / Range)

39.6 / 30.4 / 2-93 months  

 

MEG provided positive localizing results (i.e. tight dipole clusters) in 9 patients (50%) and negative results (normal or only benign variants) in other 9 patients (50%). Positive MEG localization results were concordant with the surgical resection in 5 patients: 3 of whom (60%) became completely seizure free (Engel Ia) and 2 patients (40%) achieved worthwhile seizure reduction (Engel IIIa) with the frequency of seizures decreasing from daily to monthly. MEG localization results were discordant with the resection in 4 patients, and only 1 of these patients became seizure free (25%).

Conclusion:

Current findings demonstrate the significant clinical value of MEG in presurgical evaluation of patients with drug-resistant epilepsy. In 89% of patients with positive localizing results (8/9), MEG appropriately estimated the location of epileptogenic zone, providing clinically relevant information, which could lead to favorable post-surgical seizure outcome.