Microinvasive Pars Plana Vitrectomy Combined ILM Peeling Versus Anti-VEGF Intravitreal Injection for Treatment-naïve Diabetic Macular Edema
Diabetic Macular Edema, Pars Plana Vitrectomy, Conbercept
About this trial
This is an interventional treatment trial for Diabetic Macular Edema
Eligibility Criteria
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
Sites / Locations
- Tianjin medical university eye hosipital
Arms of the Study
Arm 1
Arm 2
Experimental
Active Comparator
Vitrectomy group
Anti-VEGF group
Standard 25-gauge PPV will be performed by an experienced surgeon under retrobulbar anesthesia. After clearing the central vitreous, a complete posterior vitreous detachment (PVD) will be achieved with aspiration to remove the tightly attached posterior hyaloid. The vitreous will be removed by a high-speed vitrectomy surgical system (Constellation Vision System, Alcon Laboratories, Fort Worth, Texas, USA). The ILM stained with indocyanine green (ICG) will be peeled up to the vascular arcades. In case of need, panretinal photocoagulation (PRP) can be performed during surgery. The vitreous cavity will be filled with balanced salt solution (BSS) at the end of the procedure.
Patients will receive three monthly intravitreal injections of 0.5 mg Conbercept (Chengdu Kanghong Biotech Co.) with a 30-gauge syringe needle approximately 3.5-4 mm posterior to the corneal limbus under topical anesthesia.