TDCS in a patient with epilepsia partialis continua

Transcranial direct current stimulation (tDCS) can be used to modulate cortical excitability. Anodal stimulation increases, cathodal stimulation decreases cortical excitability. Only one study has evaluated the influence of tDCS on the seizure frequency in 10 patients with cortical dysplasia and showed a reduction of seizure frequency and decreased interictal epileptic discharges in the EEG after cathodal stimulation.

Here, we present the case of a 26 year-old patient suffering from epilepsia partialis continua (Kojewnikow's syndrome) with acoustically triggered myoclonic jerks of the left face following spring-summer encephalitis. The EEG showed right fronto-central spike-wave complexes (maximum F4) associated with the myoclonic jerks.

The patient was treated with tDCS over 20min on 5 consecutive days. The cathode was placed over F4. Stimulus intensity was 1mA. No adverse effects were experienced. The number of spike-wave-complexes in the EEG was measured before stimulation and after the last session. There was no improvement of the frequency of jerks and the number of spike-wave complexes even increased after the stimulation.

This case report questions a possible antiepileptic effect of cathodal tDCS in epilepsia partialis continua.