1. Department of Neurosurgery, University Hospital Düsseldorf and Medical Faculty Heinrich-Heine University, Düsseldorf, Germany
2. Department of Neurosurgery, University Hospital Cologne, Cologne, Germany
3. Institute of Pharmaceutics and Biopharmaceutics, University of Düsseldorf, Düsseldorf, Germany
4. FISCHER GmbH, Raman Spectroscopic Services, 40667 Meerbusch, Germany
5. Clinic of General- Visceral-, Vascular and Transplantation Surgery, Department of Molecular and Experimental Surgery, University Hospital Magdeburg and Medical Faculty Otto-von-Guericke University, Magdeburg, Germany
6. Jagiellonian Center for Experimental Therapeutics, Jagiellonian University, Krakow, Poland