1. Beetham Eye Institute, Joslin Diabetes Center, Boston, MA 02115, USA
2. Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
3. Physical Sciences, Inc., 20 New England Business Center, Andover, MA 01810, USA
4. Program in Liberal Medical Education, Brown University, Providence, RI 02903, USA
5. Division of Ophthalmology, Alpert Medical School, Brown University, Providence, RI 02903, USA
6. 2nd Department of Ophthalmology, University of Athens, 12462 Athens, Greece
7. Department of Ophthalmology, Harvard Medical School, Boston, MA 02115, USA