Clinical outcome following medical treatment of cavernous malformation related epilepsy

PURPOSE The study was conducted to assess the long-term outcome of antiepileptic drug (AED) treatment in drug-naïve patients with cavernous malformation (CM) related epilepsy (CRE). METHOD This is a retrospective, single-center, long-term observational study of 34 patients with previously untreated seizures related to CM. All patients were followed-up for at least two years. Drug resistant epilepsy (DRE) was defined as two or more seizures per year after trial of two appropriate AEDs. Patients who had only one seizure during the previous one year were assigned as "epilepsy with rare seizures (ERSs)". RESULTS Terminal 1-year seizure remission (1-YTR) was achieved in 22 (64.7%) patients, nine (26.5%) patients were diagnosed as DRE, and three (8.8%) patients were as ERSs. 1-YTR was achieved in 18 (52.9%) patients by the first drug regimen and in additional four (11.8%) patients by the second drug regimen. None of nine patients who failed to first two drug regimens did achieve 1-YTR. The location of CM in the temporal lobe was the only prognostic factor predicting a poor seizure outcome (p=0.012). CONCLUSION The outcome of AEDs therapy in patients who were presented with new onset of CRE was quite comparable with that of patients with newly diagnosed epilepsy. Failure to achieve seizure-free after adequate trials of two AEDs seems appropriate as the criteria for their referral to surgical treatment. For patients with temporal lobe CRE, earlier presurgical evaluation may be considered justifiable once they failed to an adequate trial of the first drug.