1. From the Department of Ophthalmology and2The Graduate School of Biomedical Sciences, University of Texas Southwestern Medical Center, Dallas, Texas; and the
2. From the Department of Ophthalmology and4These authors contributed equally to the work presented here and should therefore be regarded as equal authors.
3. Klinik und Poliklinik für kleine Haustiere, Freie Universität, Berlin, Germany.