Preface

Diabetic retinopathy (DR) is a disease characterized mainly by damage to the blood vessels in the retina. A large body of evidence supports the role of both inflammation and neurodegeneration in the development and progression of DR. Treatments for DR and diabetic macular edema (DME) have made tremendous advances in recent decades, but modalities with better efficacy and longer durability are still needed. Many ongoing trials are aiming to validate new treatment options. These range from new drugs to advances in dosing or administration of established pharmaceuticals to entirely new modalities. This book begins with a description of the mechanisms of development and progression of DME and with the characterization of the early stages of DR. Inflammation appears to be a key player in the pathogenesis of this condition. It has been noted that levels of inflammatory mediators like hypoxia-inducible factor, TNF-α, IL-6, and IL-1B, among others, are elevated in the diabetic's vitreous gel. Furthermore, oxidative stress-mediated lipid and protein-derived biomolecules not only add important mediators in the pathogenesis of DR, but also accelerate the progression and severity of microangiopathy.

Multimodal imaging represents a new diagnostic tool in the field of ophthalmology. Imaging tools such as optical coherence tomography and optical coherence tomography angiography are used for screening this pathology, but a new diagnostic advantage derived from the possibility of obtaining high-resolution retinal images of photoreceptors and retinal vessels by adaptive optics faces new perspectives in retinal physiology and pathophysiology.

This book also discusses standards and novel approaches, as well as current surgical options and treatment techniques. Anti-VEGF therapies such as ranibizumab, aflibercept, and off-label bevacizumab have become a first-line treatment for DME, however new therapeutic approaches are becoming more interesting as alternative pathways, such as the Tie-2 angiopoietin pathway, that may address unmet needs, with potential for greater efficacy or durability when compared to monotherapy or combination treatment. The book concludes with chapters on the latest concepts of vitreoretinal surgical approaches for both the DME with and/or without internal limiting membrane peeling and for proliferative DR.

> **Giuseppe Lo Giudice** San Antonio Hospital, University of Padua, Padua, Italy
