Micropulse laser treatment for new and refractory center-involved diabetic macular edema

Comparative Evaluation of Micropulse Laser in Treatment of Initial and Refractory Cases of Center-Involved Diabetic Macular Edema

This project will test whether a subthreshold 577 nm micropulse laser helps adults with new or treatment-resistant center-involved diabetic macular edema reduce retinal swelling and improve vision.

Quick facts

• Study type: Observational
• Enrollment: 50 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: The General Authority for Teaching Hospitals and Institutes (Research network)
• Locations: 1 site (Cairo)
• Trial ID: NCT07295704 on ClinicalTrials.gov

What this trial studies

This observational protocol follows adults with center-involved diabetic macular edema who receive subthreshold 577 nm micropulse laser photocoagulation, comparing outcomes in initial versus refractory cases. Treatment uses short duty-cycle pulses to deliver energy below the visible thermal endpoint, aiming to limit tissue heating while stimulating retinal repair. Key outcomes include changes in central macular thickness measured by spectral-domain OCT and best-corrected visual acuity over scheduled follow-up visits. Eligible patients have CMT between 250 and 700 µm and BCVA of 20/400 or better, with exclusions for tractional causes or recent intraocular surgery.

Who should consider this trial

Good fit: Adults (≥18) with type 1 or 2 diabetes, center-involved DME (CMT >250 and <700 µm) and BCVA ≥20/400, without active high-risk proliferative disease or recent ocular surgery, are ideal candidates.

Not a fit: Patients with vitreomacular traction, epiretinal membrane, monocular eyes, high-risk proliferative diabetic retinopathy, severe glaucoma, recent intraocular surgery, or very poor systemic control (HbA1c >10%) are unlikely to benefit.

Why it matters

Potential benefit: If successful, the approach could reduce macular swelling and improve or stabilize vision with less retinal thermal damage than conventional laser.

How similar studies have performed: Previous studies of subthreshold micropulse laser for DME have reported modest reductions in retinal thickness and occasional vision gains, though results have been mixed and evidence is less robust for refractory cases.

Eligibility criteria

Inclusion Criteria:

* Age ≥18 years.
* Both sexes.
* Patients with type 1 or 2 diabetes mellitus (DM), best-corrected visual acuity (BCVA) of 20/400 or better, and center-involved DME \[defined as a central macular thickness (CMT) of \>250 but \<700µm measured by spectral-domain optical coherence tomography\].
* Patients with any level of non-proliferative diabetic retinopathy or proliferative diabetic retinopathy with adequate panretinal photocoagulation (PRP) and no signs of disease activity determined by fluorescein angiography (FA).

Exclusion Criteria:

* Monocular eyes.
* Chronic renal failure or renal transplant because of diabetic nephropathy.
* Glycated hemoglobin (HbA1c) of more than 10%.
* Vitreomacular traction syndrome.
* Epiretinal membrane.
* PRP within 4months before the treatment.
* Intraocular surgery within 6months, including cataract or vitreoretinal operation.
* Rubeosis iridis.
* Severe glaucoma.
* High-risk proliferative diabetic retinopathy.
* Poor dilation.
* Increased foveal avascular zone.
* Any condition that could interfere with optical coherence tomography (OCT) measurement or visual acuity.

Where this trial is running

Cairo

• the General Authority for Teaching Hospitals and Institutes — Cairo, Egypt (Recruiting)

Study contacts

• Study coordinator: Hossam A Hassan, MD

Conditions Micropulse Laser; Treatment; Initial; Refractory; Center-Involved Diabetic Macular Edema