University of North CarolinaTodorova SD, Shin H, Hadar EJ, and Jewells

VL0-357

Despite 20 Antiepileptic Medications, Refractory Epilepsy is Common (30%) Surgery for Refractory Epilepsy Requires Definitive Seizure Focus Localization Classically Seizure Foci Localization for Resection is with Stage II Surgical Subdural Grid

(SD) Placement CT SD localization has been the gold standard Goal: Determine if Fusion of CT and MR (14

cases) leads improves seizure focus localization, and can be performed rapidly in the 3D lab without the need for a postdoctoral computer scientist

Pre-Op CT for Subdural Grid Placement Post-Op CT & MR for SD Grid localization Merger (not fusion) of the CT & MR preferably same day post op Pt Removed from Seizure Meds and Seizures

Provoked. Localization of the Epileptogenic Focus to Electrodes and the Underlying Brain on a Model for Surgical Resection Planning.

Resection Follow-Up

Left Hippocampal Increased T2Signal & Atrophy = MTS

S/P Temporal Lobectomy

Engel’s postop outcome II

Negative Pre-Op MRI

CT S/P SD Grid PlacementProblems Artifact &“CT Resolution”

Improved MR resolution,Poor SD Grid Visualization

Prior to SD Placement;MR read Left MTSClincally R-sided seizures

SD Grids B/L Since ClinicallyRight Temporal Lobe

Right Temporal LobectomyResulted in Engel’s Outcome I

T2

FLAIR

SEIZURE FOCUS FROM Right Sub and Anterior temporal lobe

Pre-Op Subtle Cortical Dysplasia

Post OP

Engel’s Outcome II

Engel’s Outcome IV

3D ROTATION

3D ROTATION

Merger Terra Recon process (FDA approved) allows seizure focus localization with only ½ hour of 3D lab time

Best to do the CT and MR post op to merge with SD grid in place (SDH)

14 patients were localized with 13 being 6 months or more post op:

- 7 Engle I (Free from Disabling Seizure) - 4 Engle II (90% reduction or rare disabling

sz) - 1 Engle III (worthwhile, > 50% reduction) - 1 Engle IV (less than 50% reduction) - 1 Patient Did not Undergo Resection

References:1)Ansari SF, Tubbs RS, Terry CL, and Cohen-Gadol AA. Surgery for extratemporal nonlesional epilepsy in adults: an outcome meta-analysis. Acta Neurochir 2010;152:1299-13052)Immonen A, Jutila L. Maraja-Murro A, et al. Long-term epilepsy surgery outcomes in patients with MRI-negative temporal lobe epilepsy. Epilepsia 2010;51(1):2260-269.3)Wiebe S, Blume WT, Girvin JP, and Eliasziw M. A radomised ontrolled trial of surgery for temporal lobe epilepsy. NEJM 2001;3345(5):311-318.