Epilepsy surgery is often associated with memory loss, however researchers at Great Ormand Street Hospital in London found that more precise excision of affected brain tissue in children can not only reduce seizures, but actually restore and improve the function of the temporal lobes.
The breakthrough, which was published in Brain, follows a previous study that showed children who undergo temporal lobe surgery for epilepsy show long-term improvements in intelligence.
The team, which comprised researchers from Great Ormand Street Hospital and the UCL Institute of Child Health, studied 53 patients with epilepsy, 43 of which had temporal lobe surgery in childhood and 11 that had no surgery. The patients were evaluated again as young adults, at which point 86% of the subjects no longer experienced seizures, and more than 50% were no longer taking epilepsy medication.
Those who had the surgery showed significant improvement in recollection of events and factual information, and specifically, those who had right temporal lobe surgery had improved verbal memory and those who had left temporal lobe surgery had improved visual memory.
The improvement in memory is perhaps the most significant finding of the study, as it shows that chronic seizures may hinder memory development, and that removal of the affected tissue in children allows normal temporal lobe function to be restored and improved—an outcome not normally seen in adults who have temporal lobe surgery.
The study also showed that the best memory outcomes were seen in children who had the least brain tissue removed. Often, surgeons remove brain tissue surrounding the affected area in order to maximize seizure elimination, however, the researchers suggest that less extensive, more targeted surgery can both effectively stop seizures and allow for the best memory outcome.
“Prior to this research we had little understanding of what kind of impact the surgery has on long-term memory outcome when the procedure takes place in childhood. Our findings show that surgery can make an important difference, but also that careful identification of the area of the temporal lobe to be operated on is vitally important,” Torsten Baldeweg, Professor of Cognitive Neuroscience at the UCL Institute of Child Health and lead author of the study, said in a press release.
The researchers suggested that improved imaging techniques could allow for physicians to better identify affected areas and in turn disrupt less brain tissue, allowing for the best memory outcome for young patients.