Abstracts

METABOLIC CHANGES AFTER SELECTIVE TEMPORO-MESIAL RADIOSURGERY VERSUS AMYGDALO-HIPPOCAMPECTOMY IN MESIO-TEMPORAL LOBE EPILEPSY

Abstract number : 1.294
Submission category :
Year : 2004
Submission ID : 4322
Source : www.aesnet.org
Presentation date : 12/2/2004 12:00:00 AM
Published date : Dec 1, 2004, 06:00 AM

Authors :
1Elisa Lopez, 2Jean Regis, 3Fabrice Bartolomei, 4Sophie Dupont, 5Stephane Clemenceau, 4Michel Baulac, 1Francine Chassoux, and 1Franck Semah

The purpose of our study was to compare the metabolic consequences of two selective surgical procedures in medial temporal lobe epilepsy (MTLE): selective amygdalo-hippocampectomy (SAH) and gamma-knife radiosurgery (GK). We included 18 patients with drug resistant MTLE associated with unilateral hippocampal sclerosis. 10 patients were treated by SAH (group 1) and 8 by GK (group 2). A positron emission tomography (PET) scan using 18-fluorodeoxyglucose (18FDG) and a magnetic resonance imaging (MRI) were performed twice for each patient, before SAH and GK and at least one year after. Group analysis of 18FDG-PET imaging were performed using statistical parametric mapping software (SPM99) and a group of 10 control subjects. The comparison between preoperative and postoperative FDG-PET scans demonstrated a statistically worsening of the hypometabolism after both SAH and GK. As expected in group 1, we found, a worsening of the hypometabolism in the medial temporal lobe structures (p[lt]0,001) that have been surgically removed, but also in the ipsilateral temporal pole (p[lt]0,001), in the caudate nucleus and in the thalamus, that have been anatomically spared. In group 2, we only reported a worsening of the hypometabolism in the medial temporal lobe structures (p[lt]0,01) and in the ipsilateral temporal pole (p[lt]0,007). The comparison of metabolic data after both procedures shows a similar hypometabolism worsening in the ipsilateral temporal pole, even if it was more severe after SAH than after GK on the medial temporal structures (p[lt]0,001). Our study demonstrated a less important hypometabolism worsening after GK than after SAH in the medial temporal structures, but a similar worsening in the ipsilateral temporal pole that has been anatomically spared by the surgery. This suggests that functional consequences are more serious after SAH than after GK on medial temporal structures and some distanced structures. These results have to be correlated to seizure outcome and with neuropsychological outcome after surgery.