1. Copyright restrictions may apply JAMA Ophthalmology Journal Club Slides: Macular Edema After Cataract Surgery Diabetic Retinopathy Clinical Research Network. Macular edema after cataract surgery in eyes without preoperative central-involved diabetic macular edema. JAMA Ophthalmol. Published online April 18, 2013. doi:10.1001/jamaophthalmol.2013.2313.

2. Copyright restrictions may apply Introduction There are limited data regarding visual acuity outcomes and development or exacerbation of macular edema (ME) in individuals with diabetes mellitus undergoing cataract surgery. Objective: –To estimate the incidence of central-involved ME 16 weeks after cataract surgery in eyes with preoperative evidence of diabetic retinopathy (DR) in the absence of central-involved diabetic ME (DME) preoperatively.

3. Copyright restrictions may apply Prospective multicenter observational study. Principal study participant criteria: aged ≥18 years; type 1 or 2 diabetes. Principal study eye criteria: Presence of cataract for which surgery is scheduled. Visual acuity of light perception or better. Surgery within 28 days of enrollment. Optical coherence tomographic (OCT) central subfield (CSF) thickness <250 µm (<310 µm on spectral-domain [SD] OCT). Microaneurysms or at least mild nonproliferative DR. Data Analysis: Primary outcome was development of central-involved ME at 16 weeks with ≥1 of the following criteria: OCT CSF thickness ≥250 µm (≥310 from SD-OCT) plus ≥1-step increase in logOCT from baseline. ≥2-Step increase in logOCT from baseline. Received nontopical postoperative ME treatment before 16 weeks with either of the OCT criteria met at the time of treatment. Methods

4. Copyright restrictions may apply Methods Visits –Protocol visits included a baseline preoperative visit as well as 4-week and 16- week postoperative visits. Limitations –Treatment and prophylaxis for DME and cystoid ME prior to, during, and after surgery were at the cataract surgeon’s or investigator’s discretion and hence not standardized. –Measurements of blood glucose, glycated hemoglobin, and blood pressure were not obtained during follow-up; as such, cannot determine whether sudden worsening of these features affected the outcomes. –Topical nonsteroidal anti-inflammatory drugs or topical steroids were not standardized; rather, these treatments were left to the discretion of the investigator or cataract surgeon.

5. Copyright restrictions may apply At 16-week visit, no eyes without DME at baseline (n = 17) developed central-involved ME (95% CI, 0%-20%). Of eyes where edema in the inner and outer macular subfields on OCT was definite or possible, 10% (95% CI, 5%-18%) of 97 eyes without central involvement and 12% (95% CI, 7%-19%) of 147 eyes where central macular involvement was possible had progression to definite central-involved ME. Of eyes that completed the 16-week visit, 8% received postoperative treatment for ME. Potential baseline risk factors for the development of central-involved ME or development or worsening of non–central-involved ME include: o Prior treatment for DME (P <.001). o Poorer (worse) preoperative visual acuity (P =.06). o More advanced (worse) level of DR (P =.06). Results 329 Eyes enrolled (45 sites) 293 Eyes eligible 278 Eyes (95%) completed 4-week visit 12 Eyes canceled surgery 24 Eyes ineligible 14 Eyes excluded (1 death) 279 Eyes (95%) completed 16-week visit

6. Copyright restrictions may apply Visual Acuity at 16 Weeks Results Did Not Develop Central-Involved ME (n = 246) Developed Central-Involved ME (n = 30) Baseline visual acuity Mean ± SD letter score (Snellen equivalent) 67 ± 15 (20/50)60 ± 15 (20/63) Visual acuity at 16 wk Mean ± SD letter score (Snellen equivalent) 80 ± 11 (20/25)69 ± 12 (20/40) Visual acuity change from baseline Mean ± SD letters 13 ± 149 ± 14 20/40 or better 89%67% ≥10-Letter gain (approximately ≥2 lines) 55%37% ≥10-Letter loss (approximately ≥2 lines) 3%10%

7. Copyright restrictions may apply Baseline Factors’ Association With Development of Central-Involved ME at 16 Weeks Baseline FactorTotal, No. Proportion With Central-Involved ME P Value Visual acuity at baseline, letter score (Snellen equivalent).06 ≥69 (≥20/40) 1447% 68-54 (20/50-20/80) 9113% 53-39 (20/100-20/160) 2322% ≤38 (≤20/200) 1817% Any history of DME treatment <.001 Yes 12320% No 1534% Results

8. Copyright restrictions may apply Results Baseline Factor Total, No. Proportion With Central-Involved ME P Value History of panretinal photocoagulation prior to study.50 Yes 6813% No 20810% DR severity.06 Microaneurysms only 544% Mild/moderate nonproliferative DR 1289% Severe nonproliferative DR 1414% Proliferative DR and/or prior scatter laser photocoagulation 8018% Baseline Factors’ Association With Development of Central-Involved ME at 16 Weeks (continued)

9. Copyright restrictions may apply In eyes without central-involved DME within 1 month prior to undergoing cataract extraction, no eyes without any DME at baseline developed central-involved ME, although the size of this subgroup was limited (n = 17 at 16 weeks). The incidence rates in the subgroups with preoperative DME not involving the CSF and the subgroup with DME with possible center involvement before cataract surgery were comparable at about 10%. Eyes with a history of DME treatment prior to study entry had a higher rate of central- involved ME (20%) than eyes with no history of DME treatment (4%) (P <.001) 16 weeks following cataract surgery. Overall, 86% of eyes had visual acuity of 20/40 or better. Visual acuity of this level is generally attained in a larger proportion of eyes undergoing cataract surgery among persons without diabetes. Strengths of the study include the large sample size and the multicenter nature, which provide more precise estimates for the progression of ME after cataract surgery. Lack of standardization of DME treatment is a limiting factor of the study. Comment

10. Copyright restrictions may apply This study shows that eyes with a history of DME treatment or DME immediately prior to cataract surgery are at higher risk for developing central-involved ME 16 weeks after the cataract extraction than those with no history of DME treatment or DME within 1 month of surgery. The effect of preoperative DME treatment on postoperative ME could not be evaluated in this study. Clinicians should continue to maintain vigilance in diabetic patients after cataract extraction even when central ME is not present immediately prior to cataract surgery, especially in eyes with prior DME treatment or non–central-involved DME that may be at a particularly high risk for development of central-involved ME after cataract surgery. These data may help researchers planning future clinical trials that attempt to minimize this clinically important event. It may also help physicians to explain the risk of DME progression after cataract surgery to their patients, tailored according to location of DME and history of DME treatment in a particular eye. Comment

11. Copyright restrictions may apply If you have questions, please contact the corresponding author: –Talat Almukhtar, MBChB, Jaeb Center for Health Research, 15310 Amberly Dr, Ste 350, Tampa, FL 33647 (drcrstat6@jaeb.org). Funding/Support This work was supported through cooperative agreements EY14231 and EY018817 from the National Eye Institute and the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, US Department of Health and Human Services. Conflict of Interest Disclosures A complete list of all DRCR.net investigator financial disclosures is available at http:// www.drcr.net. The National Institutes of Health participated in oversight of the conduct of the study and review of the manuscript but not directly in the design or conduct of the study; in the collection, analysis, and interpretation of the data; or in the preparation or approval of the manuscript. Contact Information