Update on Retinal Vein Occlusion.

Retinal vein occlusion represents the second leading cause of retinal vascular disorders, with a uniform sex distribution worldwide. A thorough evaluation of cardiovascular risk factors is required to correct possible comorbidities. The diagnosis and management of retinal vein occlusion have changed tremendously in the last 30 years, but the assessment of retinal ischemia at baseline and during follow-up examinations remains crucial. New imaging techniques have shed light on the pathophysiology of the disease and laser treatment, once the only therapeutic option, is now only one of the possible approaches with antivascular endothelial growth factors and steroid injections being preferred in most cases. Nowadays long-term outcomes are better than those achievable 20 years ago and yet, many new therapeutic options are under development, including new intravitreal drugs and gene therapy. Despite this, some cases still develop sight-threatening complications deserving a more aggressive (sometimes surgical) approach. The purpose of this comprehensive review is to reappraise some old but still valid concepts and to integrate them with new research and clinical data. The work will provide an overview of the disease's pathophysiology, natural history, and clinical features along with a detailed discussion on the advantages of multimodal imaging and of the different treatment strategies with the aim of providing retina specialists with the most updated knowledge in the field.