Prediction of seizure-onset laterality by using Wada memory asymmetries in pediatric epilepsy surgery candidates.
OBJECTIVE
Because the capacity of intracarotid amobarbital (Wada) memory assessment to predict seizure-onset laterality in children has not been thoroughly investigated, three comprehensive epilepsy surgery centers pooled their data and examined Wada memory asymmetries to predict side of seizure onset in children being considered for epilepsy surgery.


METHODS
One hundred fifty-two children with intractable epilepsy underwent Wada testing. Although the type and number of memory stimuli and methods varied at each institution, all children were presented with six to 10 items soon after amobarbital injection. After return to neurologic baseline, recognition memory for the stimuli was assessed. Seizure onset was determined by simultaneous video-EEG recordings of multiple seizures.


RESULTS
In children with unilateral temporal lobe seizures (n = 87), Wada memory asymmetries accurately predicted seizure laterality to a statistically significant degree. Wada memory asymmetries also correctly predicted side of seizure onset in children with extra-temporal lobe seizures (n = 65). Although individual patient prediction accuracy was statistically significant in temporal lobe cases, onset laterality was incorrectly predicted in < or =52% of children with left temporal lobe seizure onset, depending on the methods and asymmetry criterion used. There also were significant differences between Wada prediction accuracy across the three epilepsy centers.


CONCLUSIONS
Results suggest that Wada memory assessment is useful in predicting side of seizure onset in many children. However, Wada memory asymmetries should be interpreted more cautiously in children than in adults.
Departments of Occupational Therapy and Neurology, Medical College of Georgia, Augusta, Georgia 30912-0700, USA. glee@mail.mcg.edu
Gregory P
GP
Lee
Yong D
YD
Park
Ann
A
Hempel
Michael
M
Westerveld
David W
DW
Loring
D000293:Adolescent; D000367:Age Factors; D000654:Amobarbital / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects / Q000503:physiopathology / Q000601:surgery; D002343:Carotid Artery, Internal; D002648:Child; D004569:Electroencephalography / Q000706:statistics & numerical data; D004827:Epilepsy / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D005260:Female; D007839:Functional Laterality / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007802:Language; D008297:Male; D008568:Memory / Q000187:drug effects* / Q000502:physiology; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D011336:Probability; D014743:Videotape Recording
D000654:Amobarbital