Abstracts

Rationale: Temporal lobe epilepsy(TLE) is the most common type of epilepsy. Almost 60% of partial seizures arise in the temporal lobe. Efficacy of antiepilepic medications has been studied in partial epilepsy and not in specific types of partial epilepsy ie. Temporal, Frontal, Parietal or Occipital lobe epilepsy. The responder rates with lamotrigine in patients with partial seizures ranged from 20% to 33%. This study was undertaken to determine the efficacy of lamotrigine in the treatment of TLE. Methods: This is a retrospective study using the database of around 1600 epilepsy patients at The Nebraska Epilepsy Center. The patients were classified as having temporal lobe epilepsy based on the following criteria: A. Video-EEG confirmation of temporal lobe epilepsy by ictal and interictal recordings and no other contradictory data, Or B. two or more of the following criteria, 1- Clinical features consistent with TLE 2- EEG showing epileptiform discharges consistent with TLE. 3- MRI showing mesial temporal sclerosis or a temporal lobe lesion. 44 patients have met the previously listed criteria and were either started on lamotrigine or lamotrigine was added to their treatment regimen with no change in other antiepileptic medications. The average follow up was one year after making these changes. The seizure outcome was classified as: Class 1: Seizure free Class 2: > 90% reduction in seizure frequency Class 3: > 50% reduction in seizure frequency Class 4: < 50% reduction in seizure frequency Patients in Class 4 were designated as treatment failures. Results: Out of 44 patients with Temporal Lobe Epilepsy treated with Lamotrigine 25 patients (56.8 %) had > 50% reduction in seizure frequency. 14 patients (31.81%) became seizure free. 4 of them had > 90% reduction and 19 patients (43.2%) had < 50% reduction or didn't improve on lamotrigine. Outcome: Class 1: 14 patients ( 31.81 %) Class 2: 4 patients ( 9.09 %) Class 3: 7 patients ( 15.91 %) Class 4: 19 patients ( 43.18% ) Conclusions: 56.81 % ( 25 patients ) showed > 50% reduction in the seizure frequency in patients with Temporal Lobe Epilepsy who were treated with Lamotrigine. This responder rate is higher than that found in trials with Lamotrigine in all partial seizures which ranged from 20-33%. This study shows that Lamotrigine has a unique efficacy profile in the treatment of Temporal Lobe Epilepsy(TLE). Larger multi-center studies are needed to confirm this finding. Previous studies have shown such an efficacy profile for Levetiracetam in TLE. REFERENCES: 1. Matsuo F, Bergen D, Faught E, et al. Placebo-controlled study of the efficacy and safety of lamotrigine in patients with partial seizures. U.S. Lamotrigine Protocol 0.5 Clinical Trial Group. Neurology. 1993 Nov;43(11):2284-91 2. Messenheimer J, Ramsey RE, Willmore LJ, et al. Lamotrigine therapy for partial seizures: a multicenter, placebo-controlled, double-blind, cross-over trial. Epilepsia. 1994 Jan-Feb;35(1):113-21. 3. S.P. Singh, R Kumar. efficacy of levetiracetam in the treatment of temporal lobe epilepsy. epilepsia 46 suppl. 8:187 ( abst. 2.287 ), 2005