1, traumatic vitreous hemorrhage: closed eye trauma not combined with retinal detachment can wait 2 to 3 months, and then vitrectomy when not absorbed. When combined with retinal detachment, surgery should be performed as soon as possible. In patients with posterior scleral rupture injury combined with vitreous detachment, vitreous hemorrhage should be operated as early as possible, which is often combined with vitreoretinal inlay. When retinal detachment is superficial and combined with vitreous hemorrhage, the reliability of ultrasound diagnosis is affected, and ultrasound follow-up should be performed continuously. Patients with vitreous hemorrhage after intra-spherical foreign body removal should be highly alert to the possibility of retinal detachment, and vitrectomy should be performed when retinal detachment is suspected, and retinal detachment reset surgery should be performed when retinal detachment is found intraoperatively. 2. Diabetic retinopathy combined with vitreous accumulation of blood: The purpose of surgery is to remove the cloudy vitreous, cut off the traction of retinal detachment in the anterior and posterior directions within the vitreous, and peel off the retinal surface and retinal adhesions of fibrovascular diaphragm. If the vitreous hemorrhage is not absorbed for 6-8 weeks, vitrectomy and total retinal photocoagulation are feasible for those who have not undergone total retinal photocoagulation. Those who have undergone photocoagulation may wait longer. In patients with type I diabetes, vitreous hemorrhage is followed by rapid formation of retinal detachment, and surgery should be performed as soon as possible. Vitrectomy combined with total retinal photocoagulation has reduced the risk of severe vision loss from 60% to less than 2% in patients with proliferative diabetic retinopathy. 3. Other vascular disorders combined with vitreous hemorrhage: such as retinal perivasculitis, venous obstruction, etc. The principle is the same as diabetic vitreous hemorrhage. When the amount of bleeding is small, it can be absorbed spontaneously. After the absorption of vitreous hemorrhage, laser should be performed urgently, and regular follow-up should be done after photocoagulation until all the neovascularization or abnormal blood vessels have subsided, otherwise, vitreous hemorrhage will occur again. In patients with vitreous hemorrhage in both eyes, the timing of surgery can be advanced with one eye.