1. Department of Otorhinolaryngology—Head & Neck Surgery, Hospital Universitario de Salamanca, 37007 Salamanca, Spain
2. Department of Neurology, Hospital Universitario de Salamanca, 37007 Salamanca, Spain
3. Biomedical Research Institute of Salamanca (IBSAL), Faculty of Medicine, The University of Salamanca, 37007 Salamanca, Spain