The impact of resective epilepsy surgery on the brain network: evidence from post-surgical imaging

Resective epilepsy surgery can be an effective treatment for patients with medication-resistant focal epilepsy. Epilepsy resection consists of the surgical removal of an epileptic focus to stop seizure generation and disrupt the epileptic network. However, even focal surgical resections for epilepsy lead to widespread brain network changes. Understanding the impact of epilepsy surgery on the brain is crucial to improve surgical outcomes for patients. Here we provide a summary of studies imaging the postsurgical effects of epilepsy resection on the brain. We focus on MRI and PET studies of temporal lobe and paediatric epilepsy, reflecting the current literature. We discuss three potential mechanisms for surgery-induced brain changes: damage and degeneration, recovery, and reorganization. We additionally review the postsurgical brain correlates of surgical outcomes as well as the potential to predict the impact of surgery on an individual patient's brain. A comprehensive characterization of the impact of surgery on the brain and precise methods to predict these brain network changes could lead to more personalized surgeries that improve seizure outcomes and reduce neuropsychological deficits after surgery. Epilepsy surgery can be an effective treatment for medication-resistant epilepsy, but even focal resections can lead to widespread brain network changes. Sainburg et al. review evidence from imaging studies highlighting these effects and discuss their implications for brain function and seizure outcomes.