Abstracts

POSTERIOR CORTEX EPILEPTOGENIC LESIONS: CLINICAL, ELETROPHYSIOLOGICAL, IMAGING, SURGICAL, PATHOLOGICAL AND OUTCOME DATA

Abstract number : 1.435
Submission category :
Year : 2003
Submission ID : 4053
Source : www.aesnet.org
Presentation date : 12/6/2003 12:00:00 AM
Published date : Dec 1, 2003, 06:00 AM

Authors :
Charles L. Dalmagro, Tonicarlo R. Velasco, Vera C. Terra-Bustamante, Veriano Alexandre, Jr., Roger Walz, Luciana M. Inuzuka, Helio R. Machado, Carlos G. Carlotti, Jr., Joao A. Assirati, Jr., Antonio C. Santos, David Araujo, Jr., Lauro Wichert-Ana, Americo

Extratemporal epilepsies (ETE) are less frequent than temporal lobe epilepsies (TLE). They compose an heterogeneous group of patients, involve multiple types of etiologies and lesions, many of them are medically intractable and surgically amenable. In this ETE group the least well-known subgroup is the posterior cortex epilepsies where we find very few reports with large number of patients. In this study we aim to present clinical, surgical and outcome data in a consecutive serie of 34 patients.
We included 34 consecutive patients operated from 1996-2002, with post-surgical follow-up ranging from 1-7 years. There were 19 males and 15 females, ages at surgery ranging from 2 to 59 years old (mean = 21.5 years). All patients were submitted to a standardized presurgical evaluation which included: clinical history, high-resolution 1.5 T MRI, Video-EEG monitoring, neuropsychological and psychiatric evaluation, and, whenever possible, ictal SPECT.
Age at onset of epilepsy ranged from 3 days to 38 years (mean = 6.9 years), and duration of epilepsy ranged from 0.5 to 54 years (mean = 14.6 years). The main etiologies were: cortical developmental abnormalities (14 patients), gliosis (8 patients), tumor (5 patients), Sturge-Weber (4 patients), Tuberous sclerosis (2 patients) and arterious-venous malformation (1 patient). Localization of the lesions were: occipital = 9 patients, parietal = 9 patients, and multilobar = 16 patients. 8 patients had additional invasive monitoring with implantation of subdural grids and strips. 2 patients had re-operation, both became seizure-free (Engel Class I) after the second operation (Engel class III after the first operation). Overall outcome were after the first operation was: Engel Class I = 19 pts (56%); Engel Class II = 3 pts (9%); Engel Class III = 8 pts (24%); Engel Class IV = 4 pts (12%). After re-operation 2 patients moved from Engel Class III to Engel Class I, improving overall results (Engel Class I = 62%).
Epilepsies associated to posterior cortex lesions vary widely in terms of age at onset, seizure types, localization of the lesion, and etiology. Focal cortical developmental abnormalities are the main type of lesion. Post-surgical outcome, although inferior to temporal lobe epilepsy surgery, is worthwhile, with 62% of patients reaching seizure-free status.
[Supported by: FAPESP, FAEPA, CNPq]