[Etiopathogenesis in macular edema and therapeutic approach].

Macular edema is one of the most frequent cause of low vision with very different causes. It is a non-specific response to the change in the permeability of blood-ocular barrier. The tendency of the retina to form cistoid macular edema is little understood. There are situations where it is associated with leakage of the small perifoveolar capillaries as there are situations, such as diabetic macular edema, where the leakage is a diffuse thickening of the posterior pole with or without cistoid changes in macula.