What Impact Does Epilepsy Surgery Have on Cognition?
Early consideration of and evaluation for epilepsy surgery is key to maximizing cognitive benefits in patients with epilepsy, according to J. Helen Cross, MB, ChB, PhD, FRCP, OBE, who delivered a keynote address during the Presidential Symposium at the 2017 American Epilepsy Society Annual Meeting, December 1-5, 2017 in Washington, DC.
“Cognitive decline is not inevitable after epilepsy surgery,” said Dr Cross, who is the Prince of Wales Chair of Childhood Epilepsy and head of the Developmental Neurosciences Program at UCL-Great Ormond Street Institute of Child Health in London, UK. She emphasized the importance of weighing expectations of outcomes of patients and their caregivers when counseling on epilepsy surgery, noting that more often that not, families may be expecting gains in neurodevelopmental and cognitive domains, as well as psychosocial improvements in addition to seizure freedom.
While improvement in these domains is possible after resective surgery, understanding the factors that contribute to this is key to a greater likelihood of good outcomes.
Although there is a typical dip in cognition immediately after epilepsy surgery, gradual improvement is seen over 12 months and longer, especially in children, who tend to have better functional recovery than adults. While the greatest gains are typically seen in those with the lowest IQ, one study showed that over 25% of patients had a ˃15 point increase in IQ following resective surgery. Patients who undergo epilepsy surgery also demonstrate more educational attainment, less disability, and greater quality of life, among other psychosocial improvements.
Dr Cross noted that several studies suggest that improved cognitive outcomes after epilepsy surgery are also associated with antiepileptic medication withdrawal, degree of seizure freedom, and increases in brain volume.
Overall, Dr Cross emphasized that long-term cognitive function in these patients is highly-related to their preoperative function, which places increased emphasis on early intervention especially for patients with severe, treatment-resistant epilepsy.
Cross JH. Epilepsy surgery and cognition. Presented at: 2017 American Epilepsy Society Annual Meeting. December 1-5, 2017; Washington, DC.