Diabetic retinopathy is a chronic microvascular complication of diabetes mellitus and is characterized as a global epidemic. Diabetic macular edema may occur at any stage of diabetic retinopathy and is considered the leading cause of visual impairment in patients with diabetes mellitus. Although the understanding of both diabetic retinopathy and diabetic macular edema has advanced, their exact pathogenetic mechanisms remain complex and elusive.

In recent years, there have been various advances in the diagnosis and treatment of diabetic retinopathy, including diabetic macular edema. In fact, new diagnostic equipment and new medications/surgical machines for the treatment of diabetic retinopathy are of special interest. The use of optical coherence tomography-angiography (OCT-angiography) for the detection of early changes in retinal microvasculature in patients with diabetes mellitus, as well as for the prediction of treatment response has gained interest. In addition, the use of anti-vascular endothelial growth factor (anti-VEGF) agents has revolutionized the treatment of proliferative diabetic retinopathy, although the gold standard laser photocoagulation also has its role. Furthermore, new drugs have been developed and others are in the pipeline for the treatment of diabetic retinopathy/diabetic macular edema, based on different pathophysiological pathways.

The aim of this Special Issue is to collate original research, clinical studies, experimental studies and review articles on diabetic retinopathy, covering all aspects from pathophysiology to treatment. We are particularly interested in articles concerning newly developed techniques of imaging, diagnosis and treatment of diabetic retinopathy and diabetic macular edema.

Potential topics include but are not limited to the following:

• New pathophysiological pathways in diabetic retinopathy
• Epidemiology of diabetic retinopathy
• Advances in the techniques of imaging (Wide-field optical coherence tomography-OCT, Swept source OCT, OCT Angiography) of diabetic retinopathy/diabetic macular edema
• New insights into the treatment of diabetic retinopathy/diabetic macular edema, based on clinical trials, as well as real-life data
• Biomarkers in treatment response for patients with diabetic retinopathy/diabetic macular edema
• The role of glycaemic control or systemic disorders management in the treatment of diabetic retinopathy/diabetic macular edema