Abstracts

RATIONALE: To further define the role of surgery in patients with intractable bitemporal lobe epilepsy we studied outcomes and prognostic factors in 12 patients who underwent resective temporal lobe surgery.
METHODS: Patients with intractable temporal lobe epilepsy who had a symmetric bitemporal lobe implantation at the Montreal Neurological Hospital between 1990-2000 and a subsequent temporal lobe resection were reviewed. All had at least one seizure recorded independently from both temporal lobes. Patients with extratemporal MRI abnormalities or extratemporal seizure generators were excluded.
RESULTS: 12 patients (5 M) with 236 clinical and over 300 electrographic seizures in video-stereo-EEGs were reviewed. Their mean age at surgery was 34 years (20-57) and mean age at seizure onset was 16.3 years (3-37). Nine underwent a selective amygdalohippocampectomy and three had an anterior neocortical temporal resection in addition to an amygdalohippocampectomy. Two patients with less than one-year follow up were excluded. Of the remaining ten patients, with mean 4.5 years follow-up, three had excellent (class I*) and one had good (class II*) surgical outcome. Of six patients who continue to have seizures (one class III* and five class IV*), three subjectively reported more than 75% improvement in quality of their life after surgery due to reduced seizure frequency and severity, and reduced medications. The only significant differences between patients with excellent and good outcome compared to those with class III and IV outcomes were: mean seizure laterality of 91% versus 67.6% and unilateral mesial temporal atrophy versus bilateral atrophy, respectively. No statistically significant difference was seen in age of seizure onset, duration of epilepsy and precipitating factors.
CONCLUSIONS: We conclude that surgical resection is an option for the treatment of intractable bitemporal epilepsy. The goals of surgery, that is palliation by reducing seizure frequency or, more rarely, seizure freedom, should be made clear prior to surgery. Both outcomes have the potential for improving quality of life for the patient.
*Class I: Seizure freedom, Class II: Rare seizure (1-3/year), Class III: More than 90% seizure reduction, Class IV: Less than 90% seizure reduction.
Objective: At the conclusion of this presentation, the audience should better understand the role of surgery in intractable bitemporal lobe epilepsy.