Abstracts

Rationale: To evaluate the diagnostic value of statistical parametric mapping (SPM) analysis of FDG PET in localizing epileptogenic tuber/cortex in tuberous sclerosis complex (TSC). Methods: Nineteen patients with intractable epilepsy from TSC had comprehensive presurgical evaluation including FDG PET and intracranial EEG, and underwent resective surgery. The single most hypometabolic region determined by SPM analysis of FDG PET was compared with epileptogenic zone on intracranial EEG, as well as postoperative surgical outcome. For SPM analysis, the cutoff threshold was adjusted to detect the single most hypometabolic region. Results: SPM analysis of FDG PET visualized single most hypometabolic region which was concordant with intracranial EEG in 53% (10/19) while visual analysis failed to localize in all 19 patients. SPM analysis tended to be more accurate in localizing epileptogenic tuber/cortex in the patients aged above 6 years (71%, 5/7 vs. 42%, 5/12 in the patients younger than 6 years). Postoperative seizure-free outcome was likely to be higher in the patients with localizing epileptogenic tuber/cortex on SPM analysis (70%, 7/10 vs. 44%, 4/9 in the patients without localizing epileptogenic tuber/cortex) Conclusions: Our data suggest SPM analysis of FDG PET is a useful non-invasive method for localizing epileptogenic tuber/cortex, and it is more helpful in older children with TSC.