Background

Many people with epilepsy respond well to medication, but up to 40% continue to have seizures despite treatment. In these cases, surgery to remove the seizure-causing brain area can help. Scientists have long suspected that the blood-brain barrier (BBB)—which normally protects the brain from harmful substances—might be damaged in epilepsy and contribute to treatment resistance. Until now, no one had clearly shown whether this barrier heals after surgery.

Research

This study used advanced brain imaging (DCE-MRI) to examine the BBB in seven patients with drug-resistant temporal lobe epilepsy before and after surgery. Researchers also studied tissue samples from 13 patients. Imaging revealed BBB damage before surgery, particularly in brain regions near the seizure source. For five patients who became seizure-free after surgery, their follow-up scans showed a partial or full restoration of the BBB. In contrast, the BBB remained leaky in the two patients who continued to have seizures. Tissue analysis confirmed changes in genes and proteins related to the BBB and inflammation.

Potential Impact

These findings are the first to show that successful epilepsy surgery can help repair the brain’s protective barrier. This opens the door to using BBB health as a marker to predict treatment success and possibly guide future therapies.