Abstracts

INTRAOPERATIVE ECOG AND FRAMELESS STEREOTACTIC GUIDED SINGLE STAGE SURGERY FOR CORTICAL DYSPLASIA

Abstract number : 3.221
Submission category :
Year : 2002
Submission ID : 3408
Source : www.aesnet.org
Presentation date : 12/7/2002 12:00:00 AM
Published date : Dec 1, 2002, 06:00 AM

Authors :
Robert R. Goodman, David Teeple, Douglas R. Nordli, Guy M. McKhann II. Neurological Surgery and Neurology, Columbia University, New York, NY

RATIONALE: Cortical dysplasia is a common pathological substrate of medically intractible neocortical epilepsy. Because of the previously documented intrinsic epileptogenicity of human dysplastic cortex (Palmini et al), we have adopted a single stage surgical approach to many patients with cortical dysplasia.
METHODS: Patients with medically intractable, scalp EEG lateralized neocortical epilepsy and MRI documented cortical dysplasia were managed with a single stage surgical approach. Intraoperative electrocorticography (EcoG) and MR based frameless stereotaxy were used to delineate the electrophysiological and anatomical areas of abnormality respectively.
RESULTS: Fifteen patients (age 1-24 years) were managed by this approach. Intraoperative ECoG identified patterns of ictal or continuous epileptiform discharges (I/CEDs). With at least 24 months of follow-up (range 24-64 months), 8 patients are seizure free (Engel Class IA), 3 have rare seizures, and 3 have at least 75% reduction in seizure frequency. 7/8 seizure free patients had complete resection of their anatomical and electrophysiological areas of abnormality. Of the non-seizure free patients, 4/7 had incomplete lesion resection, while 3/7 had incomplete resection of the electrophysiologically abnormal area. The extent of the dysplastic abnormality impacted outcome: 6/9 patients with lesions limited to one lobe were seizure free in contrast to 2/6 patients with multilobar lesions.
CONCLUSIONS: A combination of intraoperative electrophysiological and frameless stereotactic guided anatomical localization can be used to carry out single stage epilepsy resections in many patients with cortical dysplasia. This approach avoids the need for electrode implantation and provides at least comparable results. If the anatomical lesion and area of I/CEDs can be completely resected, excellent outcome can be anticipated.
Objective: Participants should consider managing medically intractible epilepsy with cortical dysplasia without electrode implantation, understanding the importance of of maximizing anatomical and electrophysiological resection.