Retinal angiography allows the physician both to analyze intraretinal circulation and to define more completely the interrelationships between the various layers of the retina, RPE complex, and choroid. Angiography is not only documentary and supportive 
of our clinical differential diagnosis but also enables us to make reasoned therapeutic decisions, particularly in the treatment of ARMD and diabetic maculopathy. Although we may suspect a particular clinical diagnosis, angiography allows us to confirm the diagnosis and retain a "hard copy" for analysis throughout the course of the disease. Accurate analysis and meaningful diagnostic conclusions result from the recognition of several important phenomena that occur during the course of an angiographic study.