1. Department of Neurological Surgery, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA;
2. The Ohio State University College of Medicine, Columbus, Ohio, USA;
3. Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA;
4. Department of Orthopaedic Surgery, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA;
5. Division of Neuroradiology, Department of Radiology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA