1. Department of Neurosurgery, Henan Provincial People's Hospital, People's Hospital of Zhengzhou University, School of Clinical Medicine, Henan University, Zhengzhou, Henan, China;
2. Department of Neurosurgery, University of Louisville, School of Medicine, Louisville, KY, USA
3. Multi-Scale Robotics Laboratory, Swiss Federal Institute of Technology (ETH) Zurich, Zurich, Switzerland