1. Department of Anesthesiology, University of Illinois at Chicago, College of Medicine, Chicago, Illinois.
2. Departments of Ophthalmology and Neurology & Neurologic Sciences, Stanford University, Palo Alto, California.
3. Department of Ophthalmology and Visual Science, University of Illinois at Chicago, College of Medicine, Chicago, Illinois.
4. University of Virginia, Charlottesville, Virginia; Perioperative Medicine, Inova Health System, Falls Church, Virginia.