Diabetic retinopathy early patients do not have obvious symptoms, common changes are as follows: 1, frontal mosquitoes: flashing sensation or redness, blackness, darkness; 2, rapid vision loss: rapid in a short period of time vision loss, and can not be corrected with lenses, the patient adjusted vision are a blurred feeling. This situation should immediately check the fundus, early fundus lesions are very obvious, mainly venous filling and dilatation. After venous filling and dilatation, exudation and even neovascularization will continue to appear. In the early stage, if the macula is not invaded, there is no change in vision. If the macula is invaded, there will be vision loss or even difficulty in seeing in the early stage, and this condition will easily attract the attention of patients. If the macula is not invaded, the fundus lesion is also very serious. Patients often come to the clinic only when they have very blurred vision, at which time the blood sugar is very high, and only then they know it is diabetes complicated by fundus lesion.