[Risk factors for seizure recurrence and short term outcome after epilepsy surgery for mesial temporal sclerosis].

Aim: To establish risk factors for seizure recurrence and short term Engel classification after surgery for mesial temporal sclerosis (MTS).
Patients and Methods: Nested case-control study in a cohort of patients diagnosed with MTS by magnetic resonance imaging and who had at least two years of postsurgical follow-up; patients with bilateral MTS were excluded. Clinical characteristics, epileptogenic focus in video-electroencefalography (video-EEG) and surgical issues were evaluated regarding to seizure recurrence during the first two postsurgical years and Engel classification in the first and second anniversary after surgery.
Results: From October 2001 to June 2008, 144 patients with MTS were evaluated as candidates for epilepsy surgery; until June 2007, 89 patients underwent epilepsy surgery, 51.7% with left MTS. 35.8% of patients experienced seizure recurrence before two post-surgical years; presurgical risk factor associated to this recurrence was bitemporal focus or single temporal focus with contralateral dissemination by video-EEG (odds ratio = 6.32; 95% confidence interval = 1.64-26.41); and post-surgical, seizures that occurred in the first month of surgery (p = 0004). No association with seizure recurrence was found with gender, presurgical tonic-clonic seizures, MTS side and epilepsy duration. 66.3% and 75.8% of patients were Engel I classified in the first and second anniversary after surgery, respectively. 91% of operated patients showed a good outcome after two years of epilepsy surgery.
Conclusion: Epileptogenic focus location by electrophysiology is a fundamental factor in short term outcome after surgery for MTS.