Diabetic macular edema (DME) is part of diabetic retinopathy (DR) and a leading cause of central visual loss in people with diabetes . Most patients require pharmacological inhibition using anti-vascular endothelial growth factor (VEGF) agents with multiple monitoring visits that include optical coherence tomography (OCT), visual acuity test, and multiple injections.The substantial visit frequency puts pressure on ophthalmic clinics, and can impose a tremendous burden on both patients and their caregivers. Therefore, self-service examination instruments that can be portable and fast-moving become the key for realizing tele-medicine. Recently, the investigators have developed a portable, self-administrated home OCT machine, which is designed for home-based OCT scanning and monitoring for patients with retinal diseases including DME, age related macular degeneration (AMD) and choroidal neovascularization (CNV) that require multiple anti-VEGF injections. The investigators have confirmed its image quality and validated the retinal thickness measurements obtained from this device by comparing with hospital OCT (staff-administrated and clinic-based).In this study, the investigators will conduct a randomized clinical trial (RCT) to compare the efficacy and cost-effectiveness of a home OCT monitoring model versus standard hospital care model for patients with diabetic macular edema who need anti-VEGF injections.

Inclusion Criteria:

1. Age ≥18 years;

2. Diagnosis of diabetic macular edema:

   • Type 1 or type 2 diabetes mellitus;
   • Center-involved macular edema;

3. Willing to receive anti-VEGF treatment;

4. Media clarity, pupillary dilation, and individual cooperation sufficient for adequate OCT examination;

5. Able to operate self-administratedhome OCT by themselves or with the help of family;

6. Travel time from home to hospital: within 2 hours driving.

7. Able and willing to provide informed consent.

Exclusion Criteria:

1. History of systemic anti-VEGF or pro-VEGF treatment within 4 months prior to randomization. (These drugs should not be used during the study);
2. History of corticosteroid treatment (intravitreal or peribulbar) at any time in the past 4 months;
3. History of macular laser photocoagulation in the past 4 months;
4. Macular edema due to reasons other than diabetes;
5. Coexisting ocular diseases that might alter visual acuity during the course of the study, such as retinal vein or artery occlusion, uveitis or other ocular inflammatory disease, neovascular glaucoma, etc.);
6. Hypertension (systolic blood pressure (BP) above 180 or diastolic BP above 110);
7. History of myocardial infarction, other acute cardiac event requiring hospitalization, stroke, transient ischemic attack, or treatment for acute congestive heart failure within 4 months prior to randomization;
8. Pregnant or lactating;
9. Currently participating in other clinical trials;