Abstracts

RATIONALE: While epilepsy surgery is a successful treatment for intractable partial seizures, many adults undergoing epilepsy surgery have onset in childhood with over a decade of uncontrolled seizures. The objectives of this study are to review the clinical characteristics of children (0-18 yrs) and adults undergoing epilepsy surgery in a single population and to compare the clinical syndromes, duration of epilepsy, surgical pathology, and outcome between children and adults.
METHODS: A retrospective review of the medical records of children and adults who underwent epilepsy surgery from January 1996 to June 2001 was performed amongst the 5 epilepsy surgery centers in New South Wales. Age at surgery, age at seizure onset, duration of epilepsy, surgical pathology, and outcome in terms of seizure-freedom were compared between children and adults. Multivariate logistic regression analysis was performed to identify predictors of outcome.
RESULTS: Thirty one children (3 months-12 years old at time of surgery) and 21 adolescents (13-18 years) were compared with 156 adults (19 years and above). Post-operative follow-up ranged from 6 months to 4.5 years. Mean age at surgery for children was 7.8 years, adolescents 15.8 years, and adults 34 years. Mean duration of epilepsy prior to surgery for children was 5 years, adolescents 8 years, and adults 22 years. Although temporal lobe resections were the most common surgery across the groups (children and adolescents 52%, adults 77%), extratemporal lobe resections were more commonly seen in children and adolescents (19% and 33% respectively) than in adults (12%). Temporal lobe resections in adults resulted in class I (seizure-free) outcome in 63%, and in children and adolescents class I outcome was 78%. Mesial temporal sclerosis was the most common temporal lobe pathology in adults whereas in children, tumours (Dysembryoplastic Neuroepithelial Tumor, ganglioglioma, low grade astrocytoma), were the most common. Extratemporal resections in adults resulted in class I outcome in 47% whereas in children, class I outcome was 62%. Tumour was the most common extratemporal lobe pathology followed by cortical dysplasia in both children and adults. There was no statistical difference between children and adults in terms of age at surgery, age at seizure onset, duration of epilepsy, pathology and outcome. The only independent predictor of good outcome identified by logistic regression in both groups was surgery type. In particular, the odds of a good outcome after temporal lobe surgery were significantly better than after extratemporal lobe surgery.
CONCLUSIONS: Despite the larger number of extratemporal resections and more varied pathology in children, the results of epilepsy surgery are very good. The frequency of seizure-free outcome after epilepsy surgery was similar for children and adolescents and comparable to outcome in adults. A long duration of seizures prior to surgery did not adversely affect outcome in terms of seizure freedom.