<qa>  What is the primary outcome of the study?Using a factorial design, this study will compare 1 diode micropulse laser photocoagulation to mild ETDRS style focal photocoagulation and, 2 treatment with a COX-2 inhibitor celecoxib, or placebo prior to and following laser photocoagulation. The primary outcomes are a visual acuity drop or increase of 15 letters or more from baseline to year 3. The secondary outcome is a significant reduction in macular edema, defined as a 50 reduction in thickening as measured by Optical Coherence Tomography OCT, a two step reduction in macular thickness compared to standard stereoscopic fundus photographs, and a 50 reduction in the area of leakage as measured by fluorescein angiography. The University of Wisconsin Fundus Photography Reading Center will grade OCT, photographs, and angiograms and will be masked to treatment assignment. Other secondary outcomes will include the timing of the first required laser treatment, changes in visual acuity throughout the study, and the number of laser treatments required during the course of the study. In addition, all adverse events and abnormal laboratory values will be collected and tabulated. Specific objectives regarding safety and efficacy follow: 