Intravitreal injection with anti-vascular endothelial growth factor (anti-VEGF) in diabetic macular edema (DME) versus vitrectomy with internal limiting membrane (ILM) peeling with anti-VEGF as an adjuvant

Summary Background: Diabetic macular edema (DME) is a globally growing health problem and considered the most common form of sight-threatening retinopathy in diabetic patients. Although focal or grid laser photocoagulation was the mainstay of treatment, anti-vascular endothelial growth factor (VEGF) agents are now the standard of care. However, these therapies are expensive and some patients show inadequate response. Purpose: To determine the effect of pars plana vitrectomy (PPV) for DME with preoperative intravitreal bevacizumab (IVB) compared to anti-VEGF only. Methods: This was a retrospective study between 2011 and 2016 of 260 eyes of 130 patients who had vitrectomy for DME (n=130, PPV group, single surgeon AV) and patients who had IVI of anti-VEGF only (n=130, IVI group) were followed for at least 12 month. Charts were reviewed for best corrected visual acuity (BCVA), central macular thickness (CMT) measured by optical coherence tomography (OCT). Results: The mean BCVA in LogMAR improved from 1.08 ± 0.64 at baseline to 0.71 ± 0.55 at 12-month in the PPV group (P < 0.0001) and in the IVI group, from baseline 0.49 ± 0.39 to 0.42 ± 0.36 at 12-month (P < 0.029). The mean CMT improved from 442 ± 200 μm at baseline to 348 ±149 μm at 12-month in the PPV group (P < 0.001). The mean CMT improved from 439 ± 166 μm at baseline to 368 ± 144 μm μm at 12-month in the IVI group (P < 0.001). Preoperative IVB, compared to without IVB, leads to reduction in intraoperative (6 cases vs. 10 cases) and postoperative bleeding (3 cases vs. 13 cases). Conclusion: Vitrectomy with internal limiting membrane peeling is a cost-effective procedure which consistently results in central macular thickness reduction and leads to clinically significant improvement in BCVA comparable to serial intravitreal injection of anti-VEGF. Careful patient selection and meticulous preoperative OCT assessment are critical steps in the decision-making process. Preoperative intravitreal bevacizumab was associated with reduced intraocular bleeding intra- and postoperatively. The complication rate of vitrectomy is low and similar to what has been reported for this procedure. A large, comparative, prospective, randomized clinical trial of these two treatments is needed to determine which therapy is more effective