Macular edema

Macular edema occurs when fluid collects within the retinal layers of the macula secondary to abnormal perifoveal retinal capillary permeability caused by the release of inflammatory mediators and/or the presence of tractional forces. The swelling is responsible of severe visual acuity impairment and distortion of central vision, as the macula holds tightly packed cones that provide sharp and clear central vision. Macular edema is a common finding in the course of many pathologic conditions and it is classified according to its etiology. The diagnose and classification of macular edema has deeply improved thanks to the wide diffusion of new imaging techniques. Causes of macular edema include diabetes, macular degeneration, uveitis, retinal vascular occlusion and other entities such as iatrogenic, tumor and genetic ocular diseases. Effective management of macular edema is based on recognizing the pathogenic factors that are operative in a given disease setting. A variety of pharmacologic agents targeting inflammatory and vasoactive molecules, such as vegf, have been shown to reduce macular edema and improve visual function. Vitreoretinal surgical procedures are used to reduce the tractional components of macular edema, where present. Although treatment options are expanding with the development of new drugs, laser photocoagulation remains the gold standard of treatment in several cases and long-term efficacy and safety of most new approaches have yet to be established in controlled clinical trials.