1. Department of Ophthalmology, Dean McGee Eye Institute, Oklahoma City, Okla.
2. Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Tex.
3. Kaiser Permanente, Antioch Medical Center, Antioch, Calif.
4. Texas A&M Medical School, Dallas, Tex.
5. Byers Eye Institute, Stanford Medical Center, Palo Alto, Calif.