Department of Neurosurgery, University Hospital of Lausitz, Lausitz, Germany
LMU University Hospital, Munich, Bavaria, Germany
Center for Spinal Surgery and Neurotraumatology, Berufsgenossenschaftliche Unfallklinik, Frankfurt am Main, Hessen, Germany
Montefiore Medical Center, Bronx, New York, United States
University Hospital Center of Nantes, Nantes, France
LMU Klinikum, Munich, Bavaria, Germany
University Hospital Frankfurt, Frankfurt, Germany
University Hospital Bonn, Bonn, Germany
Research Center Borstel, Borstel, Germany
University Hospital of Cologne, Cologne, Germany
Klinikverbund Allgäu, Kempten, BaBaden-Württembergs, Germany
Frankfurt Universitätsklinikum, Frankfurt, Hessen, Germany
Klinik für Strahlentherapie, Cyberknife und Radioonkologie Universität zu Köln, Cologne, NRW, Germany
Royal Papworth Hospital, Cambridge, United Kingdom
University of Nottingham, Nottingham, United Kingdom
University of California Los Angeles, Los Angeles, California, United States
Department of Functional Upper GI Surgery, Cologne, NRW, Germany
University Hospital Cologne, Cologne, NRW, Germany