REFRACTORY EPILEPSIES WITH PERI-ROLANDIC EPILEPTOGENIC ZONES: ETIOLOGIES, CONTRIBUTION OF INTRACRANIAL RECORDINGS, SURGICAL TECHNIQUES, AND OUTCOME
Abstract number :
3.238
Submission category :
Year :
2002
Submission ID :
2546
Source :
www.aesnet.org
Presentation date :
12/7/2002 12:00:00 AM
Published date :
Dec 1, 2002, 06:00 AM
Authors :
Fabiana Mugnol, Andre Palmini, Eliseu Paglioli-Neto, Jaderson Costa da Costa, Eduardo Paglioli, Victor Martinez, Mirna Portuguez, Ney Azambuja, Gilberto Trentin, Ligia Coutinho, Sergio Raupp, Jo[atilde]o-Rubi[atilde]o Hoefel-Filho. Porto Alegre Epilepsy S
RATIONALE: Refractory seizures with a sensorimotor semiology suggestive of an epileptogenic zone (EZ) around the rolandic sulcus are often seen in patients referred for preoperative evaluation. There is hardly a consensus on how to evaluate these patients and whether they may or may not be suitable surgical candidates.
We wanted to define the spectrum of etiologies of medically refractory perirolandic epilepsies, and to address some debatable issues pertaining to neurophysiological evaluation and surgical candidacy.
METHODS: We reviewed the medical and surgical records and personally interviewed 17 operated patients whose preoperative seizure semiology and non-invasive EEGs were strongly suggestive of an EZ around the rolandic sulcus. Patients were followed from 1 to 9 years (mean 5.18). Seven had subdural strips and grids to further localize the EZ and eloquent cortex. Resection of the lesion and of the putative EZ were rated as complete or partial. Outcome was analyzed according to Engel[scquote]s classification.
RESULTS: MRI showed lesions in 12 of the 17 patients (70.5%). Eleven of the 15 (64.7%) in whom both pathology and MRI were available had malformations of cortical development (MCD: 9 Taylor-type focal cortical dysplasia, 1 non-Taylor FCD, and one hemimegalencephaly). Three others had gliotic lesions and one had a normal pathological examination. Intraoperative cortical stimulation was performed in 12 patients, and elicited functional responses in 8 (66.6%). Overall, 6 patients (35.3%) were in outcome class I and all the others were in classes III or IV, including 4 of the 5 (80%) MRI-negative patients. Two of the 7 patients (28.5%) in whom subdural electrodes were implanted were seizure free, while the same results were achieved by 4 of the 8 (50%) who had only non-invasive evaluation. Complete resection of the lesion was feasible in only 4 of the 12 patients (33.3%) in whom MRI identified a structural lesion. Three of them are seizure free (75%), contrasting with only 1 of the other 8 (12.5%) who had only partial resections (p[lt]0.05).
CONCLUSIONS: MCD are the foremost etiology of medically refractory perirolandic epilepsies and, not unexpectedly, surgical outcome is heavily related to the feasibility of complete lesion resection, often precluded by functional constraints. Subdural electrode implantation had no positive impact on outcome.
[Supported by: FAPERGS]