1. Department of Anaesthesiology and Intensive Care Medicine, Medical University of Innsbruck, Innsbruck, Austria
2. Department of Radiology, Medical University of Innsbruck, Innsbruck, Austria
3. Department of Mathematics, Faculty of Mathematics, Computer Science and Physics, University of Innsbruck, Innsbruck, Austria
4. Faculty of Engineering and Science, University of Greenwich, Greenwich, United Kingdom
5. Faculty of Medicine, University of Münster, Münster, Germany