1. Department of Neurosurgery, University of Utah, Salt Lake City, Utah, USA
2. School of Medicine, University of Utah, Salt Lake City, Utah, USA
3. Department of Neurosurgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
4. Global Neurosciences Institute, Philadelphia, Pennsylvania, USA
5. Department of Neurosurgery, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA