Diabetes can cause damage to various organs of the body, including the heart, brain and kidney, and can also cause a variety of eye diseases, such as diabetic retinopathy, diabetic macular edema, cataract, neovascular glaucoma, optic neuropathy, uveitis, and ocular muscle paralysis diplopia. Among them, diabetic retinopathy is one of the most common blinding eye diseases. The disease can be non-sensitive in the early stages, with varying degrees of visual impairment as the lesion progresses, and in severe cases, complete blindness. Diabetic patients often ignore the potential danger of this disease due to incomplete treatment or only intermittent treatment, coupled with mild symptoms. In addition, there are some “healthy” people who have been undetected for a long time because of their mild symptoms, and then have their diabetes detected in the ophthalmology department years later when they develop eye lesions. Many of these patients have already missed the best time for treatment by the time they are seen. Early detection and early formal treatment can help maintain visual function, while late treatment has a poor prognosis. Clinical manifestations and prognosis: Diabetic patients often already have obvious fundus changes such as retinal microangioma, hemorrhage, exudation and vascular changes before the appearance of vision loss. Once the sudden vision loss due to vitreous hemorrhage indicates that the lesion has entered an advanced stage, if not previously treated with regular fundus laser therapy, although conservative treatment such as drugs can make the hemorrhage partially absorbed and vision improve, it often cannot avoid Repeated vitreous hemorrhage that eventually progresses to an involved retinal detachment within weeks or months. Vitreoretinal surgery can remove the accumulated blood, reset the retina, and save the visual function to some extent. However, there may still be recurrent postoperative hemorrhage, progression of fundus ischemia, neovascular glaucoma, and optic nerve atrophy. Some patients may need to undergo multiple surgical procedures. Diagnostic tests: Routine eye examinations including visual acuity, intraocular pressure, slit lamp, and fundoscopy can diagnose most diabetic eye diseases. Dilated pupils help the doctor examine the fundus in more detail, but are not indicated for patients with closed-angle glaucoma. Fundus photography helps patients understand their condition and monitor changes in their condition. If fundus lesions progress, a fundus fluorescence angiogram (FFA) may be necessary to determine if laser treatment of the fundus is needed, as long as systemic conditions allow. Other special tests such as ultrasound, OCT and electrophysiology may also be required depending on the condition. Prevention and treatment: Fundus pathology is a late complication of diabetes. Strict glycemic control can reduce the risk and progression of diabetic retinopathy. This includes proper diet, exercise, medication control, monitoring and self-education. Smoking can aggravate ischemia and hypoxia in the body, and patients diagnosed with diabetic eye disease should avoid smoking and alcohol. Healthy individuals should also have regular checkups after a certain age to avoid missing the diagnosis of diabetes. Early lesions can remain stable and unchanged for several years, while advanced lesions may progress rapidly within weeks. Patients with diabetes should have annual eye and fundus exams, or three to six month exams if blood glucose control is not optimal or if they already have eye changes such as vision loss, or closer follow-up as recommended by their doctor. Standard treatment includes total retinal photocoagulation at the appropriate time, usually done in several sessions and supplemented by laser therapy as appropriate depending on the progression of the lesion. Patients who miss treatment may need to receive intraocular laser treatment as part of the procedure. If there has been recurrent vitreous hemorrhage, or if vitreous hemorrhage persists without resorption, or if the retina is detached, then vitreoretinal surgery will be required provided that the systemic condition is stable. Eventual causes of complete blindness in patients include ischemic retina, optic neuropathy, and neovascular glaucoma.