1. Department of Neurosurgery (FV, KW, CF, J-HK, JB, AER), Medical Center - University of Freiburg, Germany; Stanford CSF Leak Headache Program (IC), Stanford Headache Clinic, Stanford School of Medicine, CA; Department of Psychosomatic Medicine and Psychotherapy (CL); and Department of Neuroradiology (NL, HU), Medical Center - University of Freiburg, Germany.