Abstract
Positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) has been used for presurgical localization of epileptogenic foci, however in non-surgical patients, the correlation between cerebral glucose metabolism and clinical severity has not been fully understood. The aim of this study was to evaluate the glucose metabolic profile using 18F-FDG PET-CT imaging in patients with epilepsy. Methods: One hundred pediatric epilepsy patients who have received 18F-FDG PET-CT, magnetic resonance imaging (MRI) and electroencephalography (EEG) examinations were respectively included. Fifteen age-matched controls were included. 18F-FDG PET images were analyzed by using visual assessment combined with statistical parametric mapping (SPM) analysis. Absolute asymmetry index (|AI|) were calculated in patients with regional abnormal glucose metabolism. Results: Visual assessment combined with SPM analysis of 18F-FDG PET images detected more patients with abnormal glucose metabolism compared to the visual assessment only. The |AI| significantly positively correlated with seizure frequency (P < 0.001), but negatively correlated with the time since last seizure (P < 0.01) in patients with abnormal glucose metabolism. The only significant contributing variable to the |AI| was the time since last seizure, both in patients with hypo-metabolism (P = 0.001) and hyper-metabolism (P = 0.005). Higher values of |AI| were found in the drug-resistant compared to the seizure remission in patients with either hypo-metabolism (P < 0.01) or hyper-metabolism (P = 0.209). In the post 1-year follow-up PET studies, significant change of |AI| (%) was found in patients with clinical improvement compared to those with persistence or progression (P < 0.01). Conclusion: 18F-FDG PET imaging with visual assessment combined with SPM analysis could provide cerebral glucose metabolic profile in non-surgical epilepsy patients. |AI| might be used for evaluation of clinical severity and progress in these patients. Patients with a prolonged period of seizure freedom may have more subtle (or no) metabolic abnormalities on PET. The clinical value of PET might be enhanced by timing the scan closer to clinical seizure(s).
- Neurology
- PET/CT
- epilepsy
- glucose metabolism
- positron emission tomography (PET)
- statistical parametric mapping (SPM)
- Copyright © 2017 by the Society of Nuclear Medicine and Molecular Imaging, Inc.