Increased Cortical Uptake of [alpha][11C]methyl-L-tryptophan Detected by PET in Children with Intractable Epilepsy.
Abstract number :
2.204
Submission category :
Year :
2001
Submission ID :
2308
Source :
www.aesnet.org
Presentation date :
12/1/2001 12:00:00 AM
Published date :
Dec 1, 2001, 06:00 AM
Authors :
C. Juhasz, M.D., Pediatrics, Wayne State University, Detroit, MI; D.C. Chugani, Ph.D., Pediatrics/Radiology, Wayne State University, Detroit, MI; O. Muzik, Ph.D., Pediatrics/Radiology, Wayne State University, Detroit, MI; E. Asano, M.D., Pediatrics, Wayne
RATIONALE: Increases of [alpha][11C]methyl-L-tryptophan (AMT) uptake on PET are seen in up to 50% of patients with intractable partial epilepsy of neocortical origin. In this study, we determined the localization value of focally increased cortical AMT uptake as compared to intracranial EEG data as well as surgical outcome in children with neocortical epilepsy.
METHODS: Among 11 patients with intractable non-lesional neocortical epilepsy who underwent AMT PET scan and a subsequent cortical resection, five children (ages: 2.5 - 15 years) were selected because their AMT PET scans showed a focal increase of cortical AMT uptake, and presurgical evaluation included intracranial EEG studies (with chronic EEG monitoring using subdural grid electrodes [n=3] or intraoperative electrocorticography [n=2]). Locations of increased AMT uptake (objectively defined by comparison to the contralateral homologous region) were compared to the EEG defined epileptic cortex. In patients with recurring seizures, residual cortex with increased AMT uptake was evaluated by a repeated (postoperative) AMT PET.
RESULTS: All five patients had increased AMT uptake in the frontal cortex. One patient had an additional increase in the medial frontal region. Intracranial EEG showed frontal seizure onset in 3, central seizure onset (just posterior to an area of increased AMT uptake) in 1, and temporal onset in 1 patient. Frequent interictal EEG spiking occurred in the region of increased AMT uptake and in the adjacent cortex in all cases. Two patients with cortical gliosis became seizure-free after extended frontal and fronto-parietal resections including the cortex with high AMT uptake and the surrounding spiking area. The other 3 patients (with cortical dysplasia) continued to have seizures. The region with increased AMT uptake had not been completely resected in two of them. In the third patient, whose seizures recurred 5 months postoperatively, the frontal cortex with high AMT uptake had been resected, but seizures now appeared to originate from adjacent non-resected cortex.
CONCLUSIONS: In neocortical non-lesional epilepsy, increased AMT uptake has strong lateralizing value and also localizes the general area of epileptic cortex. However, areas adjacent to increased AMT uptake may also be epileptogenic, and generous subdural EEG electrode coverage of these areas (based also on scalp EEG data) is recommended.
Support: NS/RR 38324, NS 34488
Disclosure: Grant - NS/RR 38324, NS 34488