His clinical activity focuses on diseases and surgery of the retina. His main research interest is in the molecular control of photoreceptor cell death during retinal disease. He holds (or has held) research grants from the National Eye Institute, Research to Prevent Blindness, Inc., Foundation Fighting Blindness, Midwest Eye Bank and Transplantation Center, as well as other foundations. Dr. Zacks has received numerous honors and is a member of various societies, including the American Academy of Ophthalmology, the Association for Research in Vision and Ophthalmology, the Retina Society, the Macula Society and the American Society of Retina Specialists.