A C Barnes1, D R Goldman2, N V Laver3, J S Duker3. 1. Tuft University School of Medicine, 145 Harrison Avenue, Boston, MA, USA. 2. Retina Group of Florida, Imperial Point Medical Arts Pavilion, 6333 N. Federal Hwy #300, Fort Lauderdale, FL, USA. 3. Department of Ophthalmology, New England Eye Center at Tufts Medical Center, 260 Tremont Street, Biewend Building, Boston, MA, USA.