Prognosis of children with partial epilepsy: MRI and serial 18FDG-PET.
OBJECTIVE
To study the evolution of cerebral glucose metabolism after partial seizure onset in children, and its relation to clinical variables.


METHODS
Thirty-eight children had 3.4 +/-.8 (18)FDG-PET scans over 3.0 +/- 1.3 years starting within a year after their third unprovoked partial seizure. (18)FDG-PET was analyzed with a region of interest template to measure normalized metabolism in 12 paired anatomic areas. Scans with absolute asymmetry index, |AI|, greater than 0.13 in at least one cortical region other than the cerebellum were considered abnormal. Standard clinical T1- and T2-weighted MRI (1.5 T) scans were obtained.


RESULTS
Patients with initial normal PET (n = 28) were significantly more likely to remain in good seizure control than those with abnormal initial PET. Patients with initially normal PET scans that became abnormal had longer epilepsy duration before the first PET scan, but not greater seizure frequency, than those with PET always normal. There was no evidence for progression of hypometabolism. Patients with shorter time since last seizure and higher seizure frequency were more likely to have abnormal PET scans. Six of the seven patients whose PET scans were always abnormal had poor seizure control. Febrile seizure history did not affect PET findings. MRI was strongly predictive of initial PET results (chi(2) = 13.1; p < 0.02) but did not predict fluctuation hypometabolism. A model combining MRI and initial PET was strongly predictive of clinical course.


CONCLUSIONS
Initial imaging studies can help predict clinical course for children who have had at least three partial seizures. Serial FDG-PET is affected by seizure frequency and time since last seizure.
Gaillard
W D
WD
Clinical Epilepsy Section, NINDS, Division of Intramural Research, Washington, DC, USA. wgaillar@cnmc.org
Weinstein
S
S
Conry
J
J
Pearl
P L
PL
Fazilat
S
S
Fazilat
S
S
Vezina
L G
LG
Reeves-Tyer
P
P
Theodore
W H
WH
D002648:Child; D002675:Child, Preschool; D004828:Epilepsies, Partial / Q000175:diagnosis*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18