Epilepsy surgery is an extremely effective therapeutic option for many children with drug-resistant epilepsy. In medically resistant children, the likelihood that further antiepileptic drugs (AEDs) will significantly reduce seizure frequency is less than 10%, whereas surgery leads to seizure freedom in 40–90% of appropriately selected cases, depending on the degree of resection, underlying pathology, and operative procedure. In addition, other positive postoperative outcomes are arguably considered more important and include enhanced development and behavior and improved quality of life.
Epilepsy surgery is not without risk and there is a rare risk of mortality, which must be weighed against the risk of mortality of continual seizures and potential benefits of successful surgery. There are also several surgical complications, some of which may be anticipated, such as a visual field defect following hemispherectomy, whereas others are unexpected. Rarely, there may be postoperative deterioration in other comorbid domains, namely behavior, cognition, and quality of life, all of which have significant implications for the child and family. This chapter will address the mortality and comorbidities associated with epilepsy surgery in children.
Historically, there has been a significant risk of mortality associated with neurosurgery in children, including epilepsy surgery. However, with improved surgical technique, anesthesia and postoperative care, the development of dedicated epilepsy surgery centers, and availability of new techniques of evaluation, this risk is now very low and generally estimated at 0–2%.1 Children are at higher risk of mortality in epilepsy surgery than adults. Most reports of mortality in pediatric epilepsy surgery describe isolated cases in large surgical series.2,3,4,5
Causes of early postoperative death include infections, hydrocephalus, dehydration, hemorrhage, and allergic reactions. Most mortalities related to epilepsy surgery occur in children younger than 3 years.4 Infants have a greater risk due to their relatively small blood volume and the development of coagulopathy following hemorrhage in surgery.6,7 Young hemispherectomy candidates have the highest mortality. Anatomical hemispherectomy is associated with even greater mortality due to intraoperative blood loss and of the potential for late hemosiderosis (resulting from numerous acute and chronic hemorrhages from the fragile capillaries in the subdural membrane), obstructed hydrocephalus, bleeding into the hemispherectomy cavity, and progressive brain stem shift.8 Newer functional hemispherectomy techniques involving initial tissue removal followed by disconnection of remaining structures require a shorter operating time and are associated with reduced blood loss and are therefore associated with lower mortality and morbidity than anatomical hemispherectomy procedure. However, risk of mortality in hemispherectomy remains higher than for other epilepsy surgery procedures. Hemispherectomy for hemimegalencephaly is associated with the highest risk of mortality compared with other pathologies (Rasmussen's, infarct/ischemia) due to the more complex surgery (related to the enlarged megalencephalic hemisphere and distorted anatomical landmarks), longer operative time, and greater blood loss.3
The overall low risk of mortality from epilepsy surgery must be balanced ...