Abstracts

Rationale: Temporal lobe epilepsy (TLE) is the most common epilepsy syndrome with focal epileptic seizures and in many cases, it is associated with hippocampal sclerosis (HS). Mesial temporal lobe sclerosis is usually drug resistant, and is the most common type of epilepsy requiring surgical treatment. Nowadays, surgical treatment is considered the most effective method of treatment, with favorable seizure outcome being achieved in about 60%-75% of patients and significant improvements in quality of life (QOL), with low prevalence of neurological complications. Methods: Longitudinal follow-up data on postoperative seizure control were collected in 97 patients operated for medically refractory TLE/HS at our institute between January 2001 and December 2004. Preoperative evaluation of each patient included combinations of interictal scalp EEG, at least one electroclinical seizure recorded during video-EEG monitoring, MRI, (brain PET, SPECT- in select cases) and neuropsychological evaluation, QOL 31, Stigma score for epilepsy (SSE) and age appropriate activity (AAA) were recorded. Patients underwent either anterior temporal lobectomy (ATL) or selective amygdalohippocampectomy (SAH). Patients were maintained on therapeutic dosages of their anti epileptic drugs (AEDs) for at least 1 year after surgery. In all patients who were seizure-free 1 year after surgery, dosage of the AEDs was progressively reduced until discontinuation. In those with an abnormal EEG at the time of tapering of the last AED tapering was not performed. Results: There were 63 males and 34 females in our study group. The mean age at epilepsy onset was 11 years and mean age at surgery was 23 years. The mean years of epilepsy duration was 12.4 years. Mean number of AEDs being administered to patients was 2.5. Mean follow up duration was 8.2 years (range 6 to 11 years). Sixty-nine percent of patients were completely seizure free, and 72 % of patients had Engel I or II outcome. Reduction in the dose of antiepileptic drug was seen in 75 % of patients. Complications related to the surgical procedure were rare. QOL score, SSE and AAA significantly correlated with seizure freedom and good seizure outcome. Conclusions: Surgical outcome was better in younger patients. Negative predictors of surgical outcome included long duration of epilepsy, rapid generalization, bilateral temporal discharges, persistent post surgical interictal discharges and clinical developmental delay.Non seizure outcomes were strongly dependent on the seizure outcome.