POSTOPERATIVE CHANGES OF REGIONAL CEREBRAL GLUCOSE METABOLISM IN PATIENTS WITH MESIAL TEMPORAL LOBE EPILEPSY
Abstract number :
1.224
Submission category :
Year :
2003
Submission ID :
1808
Source :
www.aesnet.org
Presentation date :
12/6/2003 12:00:00 AM
Published date :
Dec 1, 2003, 06:00 AM
Authors :
Hyun Jeong Han, Woo Suk Tae, Jee-Hyun Kim, Ki-Young Jung, Dae Won Seo, Seung Chyul Hong, Seung Bong Hong Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; Neurosurgery, Samsung Medical Center, Sungkyu
Interictal 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in refractory mesial temporal lobe epilepsy (TLE) usually shows unilateral diffuse regional hypometabolism of one mesiolateral temporal area, with or without ipsilateral extratemporal cortical hypometabolism or contralateral temporal hypometabolism. To investigate the postoperative changes of hypometabolism outside the epileptic focus, we performed SPM (statistical parametric mapping) analysis between pre- and postoperative FDG-PET.
Twenty patients with mesial TLE who had the surgery and has been seizure free for more than 2 years postoperatively were included. There were 8 right TLE and 12 left TLE. All showed hippocampal sclerosis on pathology. The differences of regional cerebral glucose metabolism between pre- and post-operative FDG-PET scans were tested by SPM in right TLE and left TLE separately. For the SPM analysis, all SPECT images were spatially normalized to PET template with linear 12 parameters affine transformation and then smoothed with 14-mm FWHM (full width at half maximum), and paired-t test was used. The significance level was set to false discovery rate corrected [italic]p[/italic] [lt] 0.05, and spatial extent was set to k [gt] 50.
After seizure free state for more than two years since the anterior temporal lobectomy with amygdalohippocampectomy was performed, regional cerebral glucose metabolism increased significantly in insula, inferior frontoparietal gyrus and cingulate gyrus of ipsilateral hemisphere to the epileptic focus, and the cingulate gyrus, orbitofrontal gyrus and basal ganglia of contralateral hemisphere. However, cerebral glucose metabolism decreased in fusiform gyrus and caudate nucleus of ipsilateral hemisphere.
The brain regions with postoperative recovery of cerebral glucose metabolism appear to be preferential pathways for the propagation of ictal and interictal discharges arisen from mesial temporal region. This finding suggests that extratemporal hypometabolism of mesial TLE is related to epileptic discharges (either interictal or ictal) and reversible.