1. Wills Eye Hospital, Mid Atlantic Retina, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
2. VitreoRetinal Surgery, Minneapolis, Minnesota, USA
3. Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
4. Associated Retinal Consultants, Oakland University William Beaumont School of Medicine, Royal Oak, Michigan, USA
5. The Retina Center, Minneapolis, Minnesota, USA
6. The Retina Institute, St. Louis, Missouri, USA