An 18-year follow-up of seizure outcome after surgery for temporal lobe epilepsy and hippocampal sclerosis
- Marta Hemb1,2,
- Andre Palmini1,2,3,4,
- Eliseu Paglioli2,5,
- Eduardo Beck Paglioli2,5,
- Jaderson Costa da Costa2,3,4,
- Ney Azambuja2,5,
- Mirna Portuguez2,3,4,
- Verena Viuniski3,
- Linda Booij6,7,8,
- Magda Lahorgue Nunes3,4
- 1Severe Epilepsies Outpatient Clinic, Neurology Service, Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Brazil
- 2Porto Alegre Epilepsy Surgery Program, Neurology and Neurosurgery Services, Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Brazil
- 3Department of Internal Medicine/Neurology, Faculty of Medicine, PUCRS, Porto Alegre, Brazil
- 4The Brain Institute (InsCer) PUCRS, Porto Alegre, Brazil
- 5Department of Surgery, Faculty of Medicine, PUCRS, Porto Alegre, Brazil
- 6Sainte-Justine Hospital Research Center, Porto Alegre, Brazil
- 7Department of Psychiatry, University of Montreal, Montreal, Canada
- 8Department of Psychiatry, McGill University, Montreal, Canada
- Correspondence to Dr André Palmini, Serviço de Neurologia, Hospital São Lucas da PUCRS. Av. Ipiranga, 6690 #220 90610-000, Porto Alegre, RS, Brazil;
- Received 28 August 2012
- Revised 31 December 2012
- Accepted 15 January 2013
- Published Online First 13 February 2013
Objectives To evaluate the very long-term clinical outcome of surgery for mesial temporal lobe epilepsy and unilateral hippocampal sclerosis (MTLE/HS) without atypical features. The impact of surgical technique and postoperative reduction of medication on this outcome was investigated.
Design Prospective longitudinal cohort follow-up study for up to18 years.
Setting Epilepsy surgery centre in a university hospital.
Patients 108 patients who underwent unilateral MTLE/HS.
Intervention Surgery for MTLE/HS.
Main outcome measure Engel classification (I). Clinical evaluations were based on systematic interviews in person or by phone. Kaplan-Maier survival curves estimated the probability of remaining seizure free. The impact of medication management in the postoperative outcome was analysed using Cox regression.
Results The probability of remaining completely seizure-free at 12 and 18 years after MTLE/HS surgery was 65% and 62%, respectively. The risk of having any recurrence was 22% during the first 24 months and increased 1.4% per year afterwards. Type of surgical technique (selective amygdalohippocampectomy vs anterior temporal lobectomy) did not impact on outcome. Remaining on antiepileptic drugs and history of generalised clonic seizure diminished the probability of remaining seizure free.
Conclusions MTLE/HS surgery is able to keep patients seizure free for almost up to two decades. Removal of the neocortex besides the mesial portion of the temporal lobe does not lead to better chances of seizure control. These findings are applicable to the typical unilateral MTLE/HS syndrome and cannot be generalised for all types of TLE. Future longitudinal randomised controlled studies are needed to replicate these findings.