1. Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois
2. Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, Illinois
3. ImmersiveTouch, Inc., Westmont, Illinois
4. Section of Neurosurgery, Department of Surgery, University of Chicago, Chicago, Illinois
5. Semmes Murphey Neurologic and Spine Institute, Memphis, Tennessee