Extensive cortical inflammation is associated with epilepsy in multiple sclerosis.

Area of Science:

• Neurology
• Neuroimaging
• Neuroinflammation

Background:

• Epilepsy occurs 3-6 times more frequently in multiple sclerosis (MS) patients than the general population.
• Conventional MRI may not detect pure intracortical lesions (ICLs) linked to seizures in MS.
• The double inversion recovery (DIR) sequence offers improved detection of ICLs.

Purpose of the Study:

• To investigate the relationship between intracortical lesions (ICLs) and epileptic seizures in relapsing remitting MS (RRMS).
• To clarify the role of ICLs in epilepsy development in MS patients.

Main Methods:

• Utilized the DIR MRI sequence to detect ICLs in 20 RRMS patients with epilepsy (RRMS/E).
• Compared findings with 80 age-, gender-, and disease-matched RRMS patients without a history of seizures.
• Matched patients based on disease duration, EDSS, and T2 lesion volume.

Main Results:

• ICLs were detected in 90% of RRMS/E patients versus 48% of RRMS patients (p=0.001).
• RRMS/E patients exhibited significantly more ICLs (7.2 vs 1.5) and a larger total ICL volume (1.2 cm³ vs 0.2 cm³).
• No significant differences in juxtacortical lesions or T2-weighted lesion volume were found between groups.

Conclusions:

• RRMS patients with epilepsy show more extensive cortical inflammation than those without seizures.
• Inflammatory intracortical lesions are strongly implicated as a cause of epilepsy in MS.