1. McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas
2. University of Texas Medical Branch School of Medicine, University of Texas Medical Branch, Galveston, Texas
3. Department of Ophthalmology, Blanton Eye Institute, Houston Methodist Hospital, Houston, Texas
4. Departments of Ophthalmology, Neurology, and Neurosurgery, Weill Cornell Medicine, New York, New York
5. University of Texas MD Anderson Cancer Center, Houston, Texas
6. Texas A and M College of Medicine, Bryan, Texas; and
7. Department of Ophthalmology, The University of Iowa Hospitals and Clinics, Iowa City, Iowa