Improved Outcomes with Earlier Surgery for Intractable Frontal Lobe Epilepsy

In the March 11, 2013 early view of the journal, Annals of Neurology, Dr. Simasathien and colleagues from the Cleveland Clinic Epilepsy Center present an important analysis exploring the prognostic implications of the duration of epilepsy and age at surgery and how it relates to seizure surgery outcomes for frontal lobe epilepsy. In this single-center research project, 158 patients underwent frontal lobe epilepsy surgery from 1995 to 2010 and a number of demographic variables were noted in order to assess the relationship of age at surgery onset and duration of one’s epilepsy prior to surgery in this particular epilepsy subgroup.

The investigators found that the mean epilepsy duration was 12 years and the mean age of surgery at 20.4 years with an estimated chance of seizure freedom at 66% at one post-operative year and 44% at five years and beyond. Seventy-five percent (75%) of occurrences occurred within the first six months after surgery. Both a younger age at surgery (that is, those younger than 18 years) and shorter epilepsy duration (less than five years) correlated with better seizure outcomes in the analysis but only the duration of epilepsy remained significant. Poor prognostic indicators included: left side resections, and seizures that occur immediately post-operatively predicted early epilepsy recurrence within the first six months after surgery. A long duration of epilepsy correlated with a late recurrence of seizures. Worse outcome was seen with longer epilepsy durations of 2, 5, and 10 years independently for adults and children; although this was only significant in children if operated on within five years of epilepsy onset. The investigators concluded that early resection may improve seizure outcomes of frontal lobe epilepsy surgery particularly in children.

Why is this important? This particular analysis has been looked at rather extensively in the area of temporal lobe epilepsy surgery but has not been well studied in frontal lobe surgery. These findings seem to suggest that early surgery is helpful for improving success in frontal lobe epilepsy cases. Nevertheless, outcomes still remain less than that of temporal lobe epilepsy surgery with the most predictive finding for poor outcome being immediate seizure outcome within the first six months after an operation.