DOES SECONDARY EPILEPTOGENESIS EXIST IN THE HUMAN BEING? A NEW SERIES OF PATIENTS WITH INDOLENT TEMPORAL LOBE TUMORS
Abstract number :
2.145
Submission category :
Year :
2003
Submission ID :
3647
Source :
www.aesnet.org
Presentation date :
12/6/2003 12:00:00 AM
Published date :
Dec 1, 2003, 06:00 AM
Authors :
Let[iacute]cia Brito Sampaio, Elza Marcia Yacubian, Maria Luiza Giraldes Manreza Neurology, Hospital das Cl[iacute]nicas da Faculdade de Medicina da Universidade de S[atilde]o Paulo, S[atilde]o Paulo, S[atilde]o Paulo, Brazil; Neurology, Escola Paulista d
To review the clinical and neurophysiological data of 21 patients with epilepsy due to temporal lobe tumors and who had undergone evaluation and surgery at the Hospital das Cl[iacute]nicas da Universidade de S[atilde]o Paulo. The aim of this study was to investigate whether the occurrence of a mirror focus was influenced either by certain clinical factors or if the surgical outcome was influenced by the presence of a mirror focus.
We included 21 patients who had undergone at least one electroencephalogram l in the pre and post [ndash] surgical period. They had had a minimun follow up of one year and a maximum of 8 years. Data underwent statistical analysis.
Eight patients had mirror focus (Group 1) and 13 did not (Group 2). In three patients of Group 1, the most frequent interictal activity was apparent on the mirror focus; in this group, three patients also had ictal epileptiform activity recorded ipsi and contralaterally to the tumor. The mean age at seizure onset, duration of epilepsy disorder and total number of seizures did not vary statistically between the two groups of patients. Generalized tonic-clonic seizures occurred more frequently in the mirror focus group. All, but one patient, with a mirror focus were seizure free at follow- up while the same happened to ten out of the 13 patients without mirror focus. The mirror focus disappeared in all eight patients in the post [ndash] surgical electroencephalogram. In this group, the patient who was not seizure [ndash] free had a seizure recorded in his post [ndash] surgical electroencephalogram with seizure onset ipsilateral to the resected tumor. The patients who were not seizure-free had either been submitted to an incomplete resection of the tumor or showed evidence of associated cortical dysplasia.
Secondary epileptogenesis occurred only in the intermediate stage. The mirror focus is not a contraindication to surgery even when interictal epileptiform activity predominates contralaterally to the tumor and neither when seizures appear to arise from the mirror focus on scalp EEG. Good surgical outcome is expected despite EEG findings that may conflict with tumor location.
[Supported by: Capes]