Treatment of Macular Edema in Vascular Retinal Diseases: A 2021 Update

Abstract

Macular edema (ME) is associated with various conditions; however, the main causes of ME are retinal vein occlusion (RVO) and diabetes. Laser photocoagulation, formerly the gold standard for the treatment of ME, has been replaced by anti-vascular endothelial growth factor (anti-VEGF) intravitreal injections. Despite its efficiency, this treatment requires frequent injections to preserve the outcomes of anti-VEGF therapy, and as many patients do not sufficiently respond to the treatment, ME is typically a chronic condition that can lead to permanent visual impairment. Generalized recommendations for the treatment of ME are lacking, which highlights the importance of reviewing treatment approaches, including recent anti-VEGFs, intravitreal steroid implants, and subthreshold micropulse lasers. We reviewed relevant studies, emphasizing the articles published between 2019 and 2021 and using the following keywords: macular edema, diabetic macular edema, retinal vein occlusion, laser photocoagulation, anti-VEGF, and intravitreal injections. Our results revealed that a combination of different treatment methods may be beneficial in resistant cases. Additionally, artificial intelligence (AI) is likely to help select the best treatment option for patients in the near future.

Review: The Development of Risk Factors and Cytokines in Retinal Vein Occlusion

“…The mechanism of RVO is complex includes VEGF and inflammation, as a consequence, anti-VEGF is not effective on all patients. Patients who do not respond to anti-VEGF therapy are recommended other therapies such as: Intravitreal injection of cortisol ( 184 – 188 ); anti-adiponectin improves angiogenesis in vivo ( 25 ); Laser photocoagulation combined with anti-VEGF intravitreal injections ( 184 ). Alternatively, another important approach is to improve risk factors such as through ambulatory blood pressure monitoring and metformin blood glucose control ( 189 ).…”

Risk Factors and Treatment Strategy for Retinal Vascular Occlusive Diseases

“…A certain number of patients with retinal vein occlusion show resistance to anti-VEGF therapy [ 24 ]. Therefore, several clinical studies and animal experiments have been conducted to find new approaches and potential targets [ 150 , 151 ]. Anti-VEGF-resistant patients may be improved by an intravitreal dexamethasone (DEX) implant.…”

Subthreshold Micropulse Laser for Diabetic Macular Edema: A Review

“…Intravitreal injections have a high efficacy and safety profile, however, on the other hand, the therapy is expensive, needs to be repeated, and can very rarely lead to endophthalmitis [7]. To preserve the therapeutic effect, frequent visits and injections are required [8].…”

“…As a second line treatment, in the case of chronic, persistent edema, intravitreal steroid administration can be performed. The therapy was approved for a DME that is resistant to anti-VEGF treatment and is preferred for ineligible patients (e.g., those who experienced cardiovascular events in the last 6 months, pregnancy, and hypersensitivity) [8]. A biodegradable intravitreal implant with dexamethasone was approved for use in DME therapy.…”