1. School of Medicine, University of California, Irvine, California;
2. Keck School of Medicine of USC, Los Angeles, California;
3. College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas;
4. Department of Neurological Surgery, Geisinger Commonwealth School of Medicine, Scranton, Pennsylvania;
5. Department of Neurologic Surgery, Mayo Clinic College of Medicine and Science, Rochester, Minnesota; and
6. Department of Neurological Surgery, University of California, San Diego, California