Effect of Vitrectomy on the Evolution of Refractory Diabetic Macular Edema

Inclusion Criteria: * Age ≥18 years * Type 1 or type 2 diabetes * At least one eye with Diabetic Macular Edema (DME) (with ophthalmoscopic evidence of center-involved DME) and Failure of medical treatment considered and conducted during at least 6 months defined as follows: * At least 4 intravitreal anti-VEGF injections given within the prior 6 months * ETDRS score ≤ 78 and ≥24 (approximate Snellen equivalent 20/32 to 20/320) * OCT (Optical Coherence Tomography) CSF (Central Subfield) thickness value (microns): Heidelberg Spectralis: ≥305 in women; ≥320 in men * Less than 5 letters gain in visual acuity (VA) after the initial Anti-VEGF treatment * Less than 25% decrease of CMT (Central Macular Thickness) after the initial Anti-VEGF treatment * Glated haemoglobin (HbA1c) \<12 % in the last 3 months before patient inclusion Exclusion Criteria: * Any history of vitrectomy for the included eye * Tractional DME: on OCT Optical Coherence Tomography), undetached posterior hyaloid membrane with anterior-posterior traction for the included eye * Blood pressure \> 180/110 (systolic above 180 OR diastolic above 110) * Intraocular pressure ≥ 25 mmHg for the included eye * Exam evidence of external ocular infection, including conjunctivitis, chalazion, or substantial blepharitis for the included eye * Exam evidence of ocular toxoplasmosis for the included eye * Aphakia for the included eye * Ocular condition with visual acuity loss that, in the opinion of the investigator, would not improve from resolution of macular edema (e.g. foveal atrophy, pigment abnormalities, dense subfoveal hard exudates, non-retinal condition, etc.) for the included eye * Condition that, in the opinion of the investigator, would preclude participation in the study (e.g. unstable medical status including blood pressure, cardiovascular disease, and glycemic control). * Myocardial infarction, other acute cardiac event requiring hospitalization, stroke, transient ischemic attack, or treatment for acute congestive heart failure within 1 month prior to enrollment * History of macular laser photocoagulation within 3 months prior to enrollment for the included eye * History of panretinal (scatter) photocoagulation (PRP) within 3 months prior to enrollment or anticipated need for PRP in the 6 months following enrollment into run-in phase for the included eye * History of major ocular surgery (including scleral buckle, any intraocular surgery, etc.) within prior 3 months or anticipated within the next 6 months following enrollment for the included eye * History of cataract extraction within 3 months prior to enrollment for the included eye * History of prior herpetic ocular infection for the included eye * Initiation of intensive insulin treatment (a pump or multiple daily injections) within 4 months prior to inclusion or plans to do so in the next 4 months. * Steroid, anti-VEGF or pro-VEGF systemic treatment within 3 months prior to inclusion or anticipated use during the study * History of chronic renal failure requiring dialysis or kidney transplant. * Participation in an investigational trial that involved treatment with any drug that has not received regulatory approval for the indication being studied within 1 month of enrollment. * For women of child-bearing potential: pregnant or lactating or intending to become pregnant within the next year. * Patient expected to move out of the area of the clinical center to an area not covered by another clinical center during the next year