Objectives:To evaluate the diagnostic value of individual noninvasive presurgical modalities and to study their role in surgical management of nonlesional pediatric epilepsy patients. Methods:We retrospectively studied 14 children (3-18 years) Concordance of localization between each test and iEEG was scored as follows: 2 ϭ lobar concordance; 1 ϭ hemispheric concordance; 0 ϭ discordance or nonlocalization. Total concordance score in each patient was measured by the summation of concordance scores for all 3 tests.Results: Seven (50%) of 14 patients were seizure-free for at least 12 months after surgery. One (7%) had only rare seizures and 6 (43%) had persistent seizures. MEG (79%, 11/14) and SISCOM (79%, 11/14) showed greater lobar concordance with iEEG than SPM-PET (13%, 3/14) (p Ͻ 0.05). SPM-PET provided hemispheric lateralization (71%, 10/14) more often than lobar localization. Total concordance score tended to be greater for seizure-free patients (4.7) than for non-seizure-free patients (3.9). Children with medically intractable epilepsy have been considered for epilepsy surgery if the epileptogenic zone is reasonably localized with noninvasive presurgical evaluation. Conclusions:1-3 Among available noninvasive tests, the most accurate and reliable tool for identification of seizure focus remains MRI. Presence of visible MRI lesion not only warrants surgical candidacy, but also predicts a favorable surgical outcome.4-7 Recent advances with high-resolution MRI may reveal the presence of brain lesions not previously detected. However, some patients continue to have no detectable lesions on MRI, despite the suggestion of a focal epileptogenic zone on seizure semiology and scalp EEG.When no lesion is seen on MRI, other noninvasive functional imaging modalities have been employed: peri-ictal SPECT and subsequent subtraction image coregistered to MRI (SISCOM) may visualize increased blood flow at the time of seizure 8,9 ; 2-deoxy-2-( 18 F)fluoro-D-glucose PET (FDG-PET) and subsequent voxel-based analysis using statistical parametric mapping (SPM) may visualize the areas of decreased metabolism 10 ; and magnetoencephalography (MEG)/magnetic source localization (MSI) may reveal the source of interictal/ictal epileptic discharges.

OBJECT Tuberous sclerosis complex (TSC) with medically refractory epilepsy is characterized by multifocal brain abnormalities, traditionally indicating poor surgical candidacy. This single-center, retrospective study appraised seizurerelated, neuropsychological, and other outcomes of resective surgery in TSC patients with medically refractory epilepsy, and analyzed predictors for these outcomes. METHODS Patients with multilesional TSC who underwent epilepsy surgery between 2007 and 2012 were identified from an electronic database. All patients underwent multimodality noninvasive and subsequent invasive evaluation. Seizure outcomes were classified using the International League Against Epilepsy (ILAE) scale. The primary outcome measure was complete seizure remission (ILAE Class 1). Secondary outcome measures included 50% responder rate, change in full-scale IQ, electroencephalography improvement, and reduction in antiepileptic drug (AED) burden. RESULTS A total of 37 patients with TSC underwent resective surgery during the study period. After a mean follow-up of 5.68 ± 3.67 years, 56.8% achieved complete seizure freedom (ILAE Class 1) and 86.5% had ILAE Class 4 outcomes or better. The full-scale IQ on follow-up was significantly higher in patients with ILAE Class 1 outcome (66.70 ± 12.36) compared with those with ILAE Class 2 or worse outcomes (56.00 ± 1.41, p = 0.025). In 62.5% of the patients with ILAE Class 2 or worse outcomes, the number of AEDs were found to be significantly reduced (p = 0.004). CONCLUSIONS This study substantiates the evidence for efficacy of resective epilepsy surgery in patients with bilateral multilesional TSC. More than half of the patients were completely seizure free. Additionally, a high proportion achieved clinically meaningful reduction in seizure burden and the number of AEDs.

Pretreatment ictal connectivity differences in children with CAE were associated with response to antiepileptic treatment. This is a possible mechanism for the variable treatment response seen in patients sharing the same epilepsy syndrome.

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The SIGFRIED (SIGnal modeling For Real-time Identification and Event Detection) software provides real-time functional mapping (RTFM) of eloquent cortex for epilepsy patients preparing to undergo resective surgery. The current study presents the first application of paradigms used in functional magnetic resonance (fMRI) and electrical cortical stimulation mapping (ESM) studies for shared functional cortical mapping in the context of RTFM. Results from the three modalities are compared. A left-handed 13-year old male with intractable epilepsy participated in functional mapping for localization of eloquent language cortex with fMRI, ESM, and RTFM. For RTFM, data were acquired over the frontal and temporal cortex. Several paradigms were sequentially presented: passive (listening to stories) and active (picture naming and verb generation.) For verb generation and story processing, fMRI showed atypical right lateralizing language activation within temporal lobe regions of interest (ROI) and bilateral frontal activation with slight right lateralization. Left hemisphere ESM demonstrated no eloquent language areas. RTFM procedures using story processing and picture naming elicited activity in the right lateral and basal temporal regions. Verb generation elicited strong right lateral temporal lobe activation as well as left frontal lobe activation. RTFM results confirmed atypical language lateralization evident from fMRI and ESM. We demonstrated the feasibility and usefulness of a new RTFM stimulation paradigm implementation during pre-surgical evaluation. Block design paradigms used in fMRI may be optimal for this purpose. Further development is needed to create age-appropriate RTFM test batteries.