Abstracts

RATIONALE: To evaluate the longer-term impact of treatment (medical vs. surgical) and seizures on cognition in children and adolescents with pharmacoresistant focal epilepsies.
METHODS: 17 medically and 54 operatively treated children/adolescents (mean age 12 [plusminus]3 yrs.) had follow-up evaluations between 2 and 12 yrs. (mean 5 yrs.). Groups were not randomized to treatment and differed at baseline with respect to seizure severity, age at onset and duration of epilepsy, pathology, and lateralization of epilepsy. 63% of the operated children had temporal lobe epilepsy (conservative 59%). The medical group had 2 (T1 baseline/ T3 long-term) the operated group 3 evaluations (T1 baseline/T2 one year/T3 long-term) Patients were evaluated with respect to seizures, drug therapy, cognition (attention, memory, language, visuo-construction), school-job carreer, quality of life, and behavior.
RESULTS: 72% of the operated patients became seizure free and 22% had [gt] 50% seizure reduction (medical: 12% seizure free, additionally 47% responders). AED had been withdrawn in 37% of the operated patients and 18% changed from polytherapy to monotherapy (medical group 6%). At baseline [T1] 30 to 50% of the patients showed impairment in one or more cognitive domains, an earlier onset, grand mal seizures, polytherapy, and greater seizure frequency being associated with poorer performance levels.
At the long-term follow-up [T3] attention and higher cognitive functions improved in the medical group (20-36%) and even more in operated patients (62-65%). Losses in these functions were rare (2-14%). As for memory, a comparabe number of patients in both groups showed deteriorated (35% medical, 39% operated) or improved (both groups 41%) performance at the long term follow-up [T3]. In the operated group, memory losses were more frequent (55% vs. 25% gains) immediately after surgery [T2]. However, there was a considerable number of children who showed improved memory later on in the time between T2 and T3 (52% vs. 27% losses).
Predictors of a better cognitive long-term outcome were better baseline performance, better seizure control, temporal lobe surgery, and surgery at younger age. Within the temporal resection group, 2/3 resections and selective surgery caused more memory impairment than lesionectomies. After surgery, and particularly when patients became seizure free, superior outcome was also observed with respect to career, behavior, self reported mood, and QOL.
CONCLUSIONS: Epilepsy surgery is very successful in achieving sustained freedom from seizures and reduction or withdrawal of AED in children with chronic epilepsy. Cognition and behavior show significant improvement particularly after temporal lobe surgery and when seizures are successfully controlled. As in adults, memory is most vulnerable to epilepsy surgery. Although, in the long run, surgical defects can be largely compensated, it appears that even younger patients are often operated too late. Thus early surgery should be considered in order to prevent mental retardation due to uncontrolled chronic epilepsy on the one hand and loss of acquired functions due to late surgery on the other hand.
[Supported by: Deutsche Forschungsgemeinschaft DFG (EL-122/6-2)]; (Disclosure: Grant - The study was supported by the Deutsche Forschungsgemainschaft DFG)