Predictors of seizure outcome after temporal lobectomy for intractable epilepsy

Authors


Knut Stavem, Foundation for Health Services Research (HELTEF), Akershus University Hospital, NO-1474 Nordbyhagen, Norway
Tel.: +47 67929460
Fax: +47 67929469
e-mail: knut.stavem@klinmed.uio.no

Abstract

Objectives – To assess predictors of outcome of temporal lobectomy for intractable epilepsy.

Material and methods – In 63 adult patients operated with anterior temporal lobectomy during 1988–92, we used logistic regression analysis to assess predictors of being seizure-free (Engel's class I) 2 years after surgery. As potential predictors, we included the following variables: gender, age at operation, age at onset of seizures, epilepsy duration, etiology, generalized vs not generalized seizures, seizure frequency, intelligence quotient, ictal electroencephalography, magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT), side of resection, and extent of the resection.

Results – About 44% of the surgery patients were seizure-free (Engel's class I) 2 years after surgery. In multivariate analysis (n = 55), MRI pathology defined as atrophy in the temporal lobe, angioma, tumor or mesial temporal sclerosis (odds ratio, OR 7.4, 95%CI: 1.7–32.9) and extent of the hippocampal resection (increase of 1 cm) (OR 2.2, 95%CI: 1.1–4.6) predicted being seizure-free.

Conclusion – Focal pathology in preoperative MRI and the extent of the hippocampal resection were the only significant predictors of being seizure-free after 2 years.

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