Abstracts

Surgical ablation of a focal epileptogenic region has been used extensively to treat intractable partial seizures. Excisional surgery is a proven safe and effective therapy for children with intractable lesional epilepsy in 50 to 90 % of the cases, but the benefit for children who lack a focal lesion or have normal or non-specific CT/MRI scans is less clear. We report the outcome of an expanded cohort of children with non-lesional intractable partial epilepsy undergoing resective surgery.
Out of 482 resective surgeries (1980-2002), 99 children had normal or non-specific CT/MRI scans (non-lesional). There were 50M, 49F between 0.5 to 32 yrs (mean= 11.18yrs). The epileptogenic region was identified on the basis of scalp ictal and interictal video-EEG (n=99); Ictal SPECT (n=28), in patients performed after 1993; subdural monitoring (n=47), and electrocorticography (n=93). MR images were obtained pre and post operatively Seizure outcome was classified as seizure-free, 90% reduction, 50% reduction and less than 50% at mean follow up greater than 10 years (2-17 years).
59/99 resections involved 1 lobe (Unilobar) Frontal =34, Temporal=24, Parietal=1. 32/99 were Multilobar (including 3 hemispherectomies), and 8 callosotomies. 43/99 (43.4 %) are seizure free, 16 (16%) experienced 90% reduction, 12 (12%) had [gt] 50% reduction, and 28 (28 %) were unchanged. There were no significant differences in the outcome based upon location or extent of resection.
Our findings confirm and extend our previous report indicating that excisional surgery is beneficial for the majority of children with intractable partial epilepsy who lack a discrete lesion on neuroimaging. Neurophysiologic monitoring and functional imaging techniques can successfully identify surgical candidates and plan surgical intervention.