1. Department of Neurological Surgery, Center for Image-Guided Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania;
2. Department of Neurosurgery, Medical University of South Carolina, Charleston, South Carolina;
3. Department of Neurosurgery, University of Helsinki, Finland;
4. Department of Neurosurgery, Emory University, Atlanta, Georgia;
5. Department of Neurosurgery, University of Southern California, Los Angeles, California