1. Department of Anatomy and Cell Biology Lewis Katz School of Medicine Philadelphia Pennsylvania
2. Department of Neurosurgery, Neurosurgery Paralysis Center Massachusetts General Hospital Boston Massachusetts
3. Department of Urology Massachusetts General Hospital Boston Massachusetts
4. Drexel University College of Medicine Drexel University Philadelphia Pennsylvania
5. Department of Anatomy and Cell Biology, Lewis Katz School of Medicine Shriners Hospitals for Children Philadelphia Pennsylvania