Postoperative alteration of cerebral glucose metabolism in mesial temporal lobe epilepsy.
To investigate postoperative changes in the cerebral glucose metabolism of patients with mesial temporal lobe epilepsy (MTLE), statistical parametric mapping (SPM) analysis was performed on pre- and postoperative (18)F-fluorodeoxyglucose PET (FDG-PET) images. We included 28 patients with MTLE who had undergone surgery and had been seizure-free postoperatively (16 had left MTLE and 12 right MTLE). All patients showed hippocampal sclerosis by pathology or brain MRI. FDG-PET images of the 12 right temporal lobe epilepsy patients were reversed to lateralize the epileptogenic zone to the left side in all patients. Application of the paired t-test in SPM to pre- and postoperative FDG-PETs showed that postoperative glucose metabolism decreased in the caudate nucleus, the pulvinar of the thalamus, fusiform gyrus, lingual gyrus and the posterior region of the insular cortex in the hemisphere ipsilateral to resection, whereas postoperative glucose metabolism increased in the anterior region of the insular cortex, temporal stem white matter, midbrain, inferior precentral gyrus, anterior cingulate gyrus and supramarginal gyrus in the hemisphere ipsilateral to resection. No significant postsurgical changes in cerebral glucose metabolism occurred in the contralateral hemisphere. Subtraction between pre- and postoperative FDG-PET images in individual patients produced similar findings to the SPM results, and additionally showed that postoperative glucose metabolism increased in the anterior thalamus in 12/28 patients (42.8%). SISCOM (subtraction ictal-interictal SPECT co-registered to MRI) performed in 17 patients showed ictal hyperperfusion in the ipsilateral temporal lobe, including the temporal stem white matter, midbrain, insular cortex and cingulate gyrus, bilateral basal ganglia and thalami, and multiple small regions in the frontoparietal lobes during seizures. This study suggests that brain regions showing a postoperative increase in glucose metabolism appear to represent the propagation pathways of ictal and interictal epileptic discharges in MTLE, whereas the postoperative decrease in glucose metabolism may be related to a permanent loss of afferents from resected anterior-mesial temporal structures.
Joo
Eun Yeon
EY
Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-Dong, Gangnam-Gu, Seoul, Korea.
Hong
Seung Bong
SB
Han
Hyun Jung
HJ
Tae
Woo Suk
WS
Kim
Jee Hyun
JH
Han
Sun Jung
SJ
Seo
Dae Won
DW
Lee
Kyung-Han
KH
Hong
Seung-Chyul
SC
Lee
Munhyang
M
Kim
Seunghwan
S
Kim
Byung Tae
BT
D000293:Adolescent; D000328:Adult; D038481:Anterior Temporal Lobectomy / Q000379:methods; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D004833:Epilepsy, Temporal Lobe / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000601:surgery; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D049268:Positron-Emission Tomography / Q000379:methods; D011184:Postoperative Period; D019275:Radiopharmaceuticals; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D005947:Glucose