1. Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, USA;
2. Department of Neurosurgery, University of Texas Medical Branch, Galveston, TX, USA;
3. Department of Neurosurgery, Baylor College of Medicine, Houston, TX, USA;
4. Lyerly Neurosurgery, Baptist Neurological Institute, Jacksonville, FL, USA;
5. Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA;
6. Department of Radiology, University of Massachusetts Medical School, Worcester, MA, USA;
7. Neurosurgical Service, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA;
8. Department of Neurointerventional Radiology, Lahey Hospital and Medical Center, Tufts University School of Medicine, Burlington, MA, USA