Transcranial direct current stimulation in adolescent and adult Rasmussen's encephalitis.

Rasmussen's encephalitis is a rare, progressive inflammatory disease that typically affects one cerebral hemisphere and causes intractable partial-onset seizures. Currently, the only effective therapy is hemispherectomy; however, this procedure is associated with irreversible neurological deficits. Novel therapeutic approaches to this condition are therefore necessary. One possible option that has not yet been extensively studied is electrical cathodal transcranial direct current stimulation (cTDCS). We describe the cases of two patients with atypical-onset Rasmussen's encephalitis who underwent cTDCS at 1- and 2-mA intensity for 60 minutes in four sessions (on days 0, 7, 30, and 60). No complications were recorded during their therapy. At follow-up evaluations 6 and 12 months later, one patient had a significant reduction in seizure frequency and one was seizure free. Additionally, both patients had improved levels of alertness and language. This is the first time that cTDCS has been applied in serial sessions to treat Rasmussen's encephalitis to avoid or delay surgical treatment.