18FDG-PET in epilepsies of infantile onset with pharmacoresistant generalised tonic-clonic seizures.
OBJECTIVE
To investigate the pathophysiology of pharmacoresistant epilepsies with cryptogenic generalised tonic-clonic seizures (GTCS) from infancy.


METHODS
18F-Deoxy-Glucose-Positron Emission Tomography 18FDG-PET) with statistical parametric mapping (SPM). Inclusion criteria were: pharmacoresistant chronic epilepsy with GTCS commencing in infancy, no focal seizures except alternating hemiconvulsions and no focal epileptic discharges in the EEG during the first year of the disease, no focal changes upon routine neuroradiological investigations, no indication of brain damage according to history and clinical examination.


RESULTS
15 boys and 15 girls with a mean age of 6.4 years (range l-14 years) were included. All still suffered from seizures despite past treatment with a mean of five drugs. Nearly all were mentally retarded, 19 to a severe and 10 to a minor degree. Fifteen were ataxic and 11 hypotonic. The EEG in 23 showed irregular generalised spike-wave discharges. PET SPM analysis revealed bioccipital hypometabolism related to sedation. Pathological monofocal hypometabolic areas were found in three, multifocal hypometabolic areas in 22 and diffuse bilateral hypometabolism in three patients. Frontal hypometabolism correlated to the degree of mental retardation, hypotonia, and ataxia. Temporomesial hypometabolism correlated to the occurrence of obtunded states and prominent delta rhythms in the EEG. Central and parietal changes were associated with the occurrence of myoclonic seizures and spike-wave discharges.


CONCLUSIONS
18FDG-PET in many of these children with cryptogenic generalised epilepsies showed multifocal hypometabolic areas of unknown aetiology. Primary cortical microdysgenesis and secondary changes due to the severe and long-standing epilepsy must be considered. Only a minority of patients showed restricted focal hypometabolism as a possible indication for surgical treatment.
Department of Paediatrics and Adolescent Medicine, Division of Neuropaediatrics and Muscular Disorders, University Hospital Freiburg, Mathildenstr. 1, D-79106 Freiburg, Germany. rudokori@kikli.ukl.uni-freiburg.de
Rudolf
R
Korinthenberg
Carola
C
Bauer-Scheid
Peter
P
Burkart
Heike
H
Martens-Le Bouar
Jan
J
Kassubek
Freimut D
FD
Juengling
D000293:Adolescent; D017668:Age of Onset; D000927:Anticonvulsants / Q000627:therapeutic use*; D001259:Ataxia / Q000150:complications; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D004351:Drug Resistance; D004569:Electroencephalography; D004827:Epilepsy / Q000453:epidemiology*; D004829:Epilepsy, Generalized / Q000150:complications / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000503:physiopathology*; D004830:Epilepsy, Tonic-Clonic / Q000150:complications / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000503:physiopathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000150:complications / Q000523:psychology; D008297:Male; D009123:Muscle Hypotonia / Q000150:complications; D019275:Radiopharmaceuticals; D012720:Severity of Illness Index; D014055:Tomography, Emission-Computed
D000927:Anticonvulsants; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18