Epidural electrical stimulation to improve chronic poststroke aphasia: a 5-year follow-up.

Aphasia is an incapacitating deficit experienced by almost 25% of patients after a left hemispheric ischemic stroke. Spontaneous recovery is considered to be limited to a period of 3 to 6 months. Although speech therapy performed during the first weeks may speed up this process and enhance its outcome, beyond this period it fails to change the global prognosis.