To evaluate the efficacy and safety of
gamma knife radiosurgery (GKS) in treating
temporal lobe epilepsy, GKS was performed in four adult patients with recurrent
complex partial seizures who underwent incomplete
anterior temporal lobectomy (ATL) but were reluctant to undergo a second resective
surgery. A marginal dose of 24.5-25Gy, corresponding to 65-70% isodose curve, was delivered to the treatment target that included the residual
amygdala and the
head and
anterior body of the
hippocampus. None of the patients had severe acute side effects but three patients had radiation-induced
MRI signal changes around the target volume 13, 20, and 24 months after GKS, respectively. All four patients had significant
seizure reduction during the first 6-month period and clinical efficacy persisted throughout the 2-year follow-up period. All of the patients also had improved
neuropsychological profiles, including
memory function and quality-of-life, compared to their pre-GKS conditions. In conclusion, the safety and clinical efficacy of GKS make it a reasonable and suitable therapeutic alternative for patients with recurrent
seizures after incomplete ATL. A higher marginal dose of >25Gy and wider coverage may be more clinically beneficial but warrant further investigation.
