Microinvasive Pars Plana Vitrectomy Combined ILM Peeling Versus Anti-VEGF Intravitreal Injection for Treatment-naïve Diabetic Macular Edema

Tianjin Medical University Eye Hospital

Status: Enrolling

Conditions: Diabetic Macular Edema; Conbercept; Pars Plana Vitrectomy

Treatments: Procedure: Vitrectomy combined with ILM peeling; Drug: Conbercept intravitreal injection

Study type: Interventional

Funder types: Other

Identifiers

NCT05728476

TianjinMUEHhbj111

Details and patient eligibility

About

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.

Enrollment: 102 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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102 participants in 2 patient groups

Vitrectomy group

Experimental group

Description:

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.

Treatment:

Procedure: Vitrectomy combined with ILM peeling

Anti-VEGF group

Active Comparator group

Description:

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.

Treatment:

Drug: Conbercept intravitreal injection