Abstracts

To study the safety of transcranial direct current stimulation (tDCS) in patients with refractory epilepsy and malformations of cortical development (MCD) as indexed by seizure frequency and epileptiform EEG discharges. Nineteen patients with MCD and refractory epilepsy underwent one session of cathodal stimulation (20 minutes, 1mA) targeting the epileptogenic focus. The number of epileptiform discharges (ED) in the EEG and seizures were measured before (baseline), immediately after as well as 15 and 30 days after tDCS treatment. Seizure frequency after the treatment was compared to baseline. Active tDCS compared to sham tDCS was associated with a significant reduction in the number of epileptiform discharges. The mean ED reduction was [ndash]64.3% (95% CI, [ndash]122.5%, [ndash]6.0%) for the active tDCS group and [ndash]5.8% (95% CI, [ndash]26.8%, 15.2%) for the sham tDCS group. There was a tendency (p=0.06) for decrease in seizure frequency after active compared to sham tDCS [mean seizure frequency decrease of [ndash] 44.0% (95% CI, [ndash]95.0%, 7.1%) for the active tDCS group and [ndash]11.1% (95% CI, [ndash] 22.2%, 44.4%) for the sham tDCS group]. This randomized, controlled study shows that tDCS is safe and well tolerated in patients with refractory epilepsy and MCD. Furthermore, the results suggest that this technique might have an antiepileptic effect based on clinical and electrophysiological criteria. (Supported by a grant from the Harvard Medical School Scholars in Clinical Sciences Program (NIH K30 HL04095) and by K24 RR018875, RO1-NS 47754, RO1-NS 20068 to A.P.-L.)