The detection of anatomical structures of fundus image like the OD, fovea and the retinal vessels is very significant in the automated detection of DR. This review outlines the principles, methods and algorithms used in the automated detection of diabetic eye diseases. The recent methods used to detect fundus image features like the optic disc (OD), fovea and retinal blood vessels, pathologies like hemorrhages, Micro aneurysms (MA), cotton wool spots and retinal exudates are discussed. We discuss the automated detection of diabetic eye diseases using image processing methods. We present the quantitative evaluation of different methods. We also discuss methodologies used by the researches in analyzing their results.