Overview

Diabetic macular edema (DME) is the main cause of vision loss in patients with diabetes. At present, anti-vascular endothelial growth factor (VEGF) intravitreal injection is the first-line therapy for DME, nevertheless, some patients do not respond well to anti-VEGF agents and often require multiple injections, which increases the psychological and economic burden of patients. Microinvasive pars plana vitrectomy (PPV) has been proven to be safe and effective for refractory DME. However, there are few studies on treatment-naïve DME. The purpose of this study is to explore whether early PPV combined with internal limiting membrane (ILM) peeling can reduce the treatment burden of DME patients, prevent vision loss, and maintain long-term stabilization of diabetic retinopathy.

Eligibility

Inclusion Criteria:

• ≥18 years of age
• Patients and their families fully understand the research and sign the informed consent form
• Diagnosed with type 1 or 2 diabetes mellitus
• Hemoglobin A1c (HbA1c) of less than 10% within 3 months
• Clear media for adequate OCT and optical coherence tomography angiography (OCTA) images
• Treatment-naïve DME diagnosed clinically
• Central subfield thickness (CST) of >300μm and intra- or subretinal fluid seen on (spectral-domain) SD-OCT
• Early Treatment Diabetic Retinopathy Study (ETDRS) BCVA between 24 and 73 letters on the day of randomization
• Treatment within 12 months of DME diagnosis
• No contraindication of vitrectomy or conbercept intravitreal injection

Exclusion Criteria:

• Any previous DME treatment (i.e. anti-VEGF injections, intraocular corticosteroids, macular photocoagulation)
• Macular edema caused by other disease (i.e. neovascular age-related macular degeneration, retinal vein occlusion, uveitis)
• Any previous intraocular surgeries (cataract surgery performed at least 3 months before study entry will not be exclusionary)
• Vision loss caused by other ocular disease (i.e. cataract, proliferative diabetic retinopathy, glaucoma, high myopia)
• A follow-up duration of less than 12 months
• Severe dysfunction of the heart, liver, kidney, lung and other organs