Timing of phacoemulsification in relation to intravitreal ranibizumab injection in diabetic patients type 2 with cataract and mild center involved macular edema

Abstract

Purpose: To compare preoperative ranibizumab (RBZ) 0.5 mg/0.05 ml three-injection protocol to postoperative protocol in cases with center involved macular edema (CiME), undergoing phacoemulsification. Patients and Methods: Cases with non-ischemic clinically significant diabetic macular edema (CSDME) were randomized into two groups. Both groups received three intravitreal RBZ injections on monthly basis. Group 1, received the first two injection 2 months before phacoemulsification and the third one was injected intraoperative by the end of surgey. Group 2 received the first injection intraoperatively followed by 2 other injections, 1 and 2 months postoperatively. Central subfield thickness (CST) was measured using spectral-domain optical coherence tomography (RTvue-100), 1 month after third injection for both groups. Results: The mean postoperative corrected distance visual acuity (CDVA) at 3 months postoperatively was significantly improved (P = 0.005) in Group 1 than in Group 2. The postoperative CST 1 month after the third injection for Group 1 was 252.5 μm ± 16 versus 270.1 μm ± 24.4 for Group 2, which was statistically significant (P = 0.02). Percentage of reduction in central foveal thickness (CFT) was 15.4% and 8%, Groups 1 and 2, respectively. The ellipsoid zone integrity showed Interruption in Group 1 in 19.4% of eyes, which was lower than in Group 2 (28%), however this was not statistically significant (P = 0.4). None of our cases developed epiretinal membranes in either groups. In Group 2 only, four cases developed subretinal fluid (SRF), and one case had cystoid changes. None of the cases developed SRF or de novo cystoid changes, till the last follow-up visit, in Group 1. Conclusion: Using RBZ repeated intravitreal injections protocol prior to phacoemulsification improved significantly CDVA and reduced the CST, than when injected postoperatively. In addition, the number of postoperative intravitreal injections that might be needed was significantly reduced when it is used preoperatively.