Macular Perfusion Changes After Anti-VEGF Versus Targeted Retinal Photocoagulation in Proliferative Diabetic Retinopathy

Summary

Diabetic retinopathy (DR) is the most common microvascular complication of diabetes mellitus (DM), while proliferative diabetic retinopathy (PDR) is the principal cause of severe visual loss in patients with diabetes. Since 1981, Panretinal photocoagulation (PRP) has been a standard of treatment for PDR. However, PRP can be associated with adverse effects, including visual field constriction, decreased night vision, and worsening of coexisting diabetic macular edema (DME). For this reason, some authors have advocated targeted treatment with PRP. Targeted retinal laser photocoagulation (TRP) is designed to treat areas of retinal capillary non-perfusion and intermediate retinal ischemic zones in PDR that may spare better-perfused tissue from laser-induced tissue scarring.

Protocol S by Diabetic Retinopathy Clinical Research Network (DRCR.net) has shown that patients that receive ranibizumab as anti-vascular endothelial growth factor (anti-VEGF) therapy with deferred PRP are non-inferior regarding improving in visual acuity to those eyes receiving standard prompt PRP therapy for the treatment of PDR.

Retinal ischemia is an important factor in the progression and prognosis of diabetic retinopathy. Regarding the effect of anti-VEGF drugs on macular perfusion, several studies have shown mixed results with an increase, decrease, or no effect on perfusion in response to anti-VEGF treatment. In many of these studies, however, patients with more ischemic retinas were not included. Fluorescein angiography (FA) was the method used to assess changes in macular perfusion after anti-VEGF injections in most of the clinical trials. Despite its clinical usefulness, however, FA is known to have documented risks. Optical coherence tomography angiography (OCTA) in macular perfusion evaluation in these cases was recommended by some investigators. Several studies have proved the reliability of OCTA in detecting and quantifying macular ischemia in diabetics.

The investigators aim to compare changes in the macular perfusion in patients with PDR after treatment with anti-VEGF therapy versus TRP versus Standard PRP using OCTA.

Conditions

• Proliferative Diabetic Retinopathy
• Vascular Endothelial Growth Factor Overexpression
• Diabetic Retinopathy

Interventions

DRUG

Bevacizumab Injection

Bevacizumab will be intravitreally injected every 4 weeks through 12 weeks then pro re nata thereafter for 12 months.

PROCEDURE

Targeted retinal photocoagulation

Targeted retinal photocoagulation will be administered to nonperfused areas detected on fundus fluorescein angiography at baseline and repeated every 3 months as needed for 12 months.

PROCEDURE

Standard pan-retinal photocoagulation

Standard pan-retinal photocoagulation will be applied to perfused and nonperfused areas of the retinal periphery at baseline and every 3 months as needed for 12 months.

Sponsors & Collaborators

• Cairo University

  lead OTHER

Principal Investigators

• Mohamed A Eldaly, MD, PhD · Cairo University

• Ayman G Elnahry, MD, PhD · Cairo University

• Wael A Yussuf, MD, MSc · Cairo University

• Ahmed A Abdel-Kader, MD, PhD · Cairo University

• Ahmed A Mohalhal, MD, PhD · Cairo University

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2021-03-30

Primary Completion

2023-03-15

Completion

2023-03-15

FDA Drug

Yes

Countries

• Egypt

Study Locations