1. Department of Neurosurgery Thomas Jefferson University and Jefferson Hospital for Neuroscience Philadelphia, Pennsylvania, USA
2. Department of Neurosurgery University of Michigan Ann Arbor, Michigan, USA
3. Department of Neurosurgery University of Miami Hospital Miami, Florida, USA
4. Neuro-Ophthalmology Service Wills Eye Hospital and Thomas Jefferson University Philadelphia, Pennsylvania, USA
5. University of Pennsylvania Philadelphia, Pennsylvania, USA
6. Amherst College Philadelphia, Pennsylvania, USA