1. Department of Oral and Maxillofacial Surgery, Klinikum der Universität München, Munich, Germany
2. Department of Orthopedics, Physical Medicine and Rehabilitation, Klinikum der Universität München, Munich, Germany
3. Department of Neurosurgery, Christian-Doppler-Klinik, Paracelsus Private Medical University, Salzburg, Austria (current address)
4. Department of Neurosurgery, Ludwig-Maximilians-University, Munich, Germany