Sudden darkening of the eyes is usually seen in fundus diseases, such as retinal artery blockage, retinal vein blockage, vitreous hemorrhage and so on. Only when the specific cause of the problem is clearly identified can symptomatic treatment be given to prevent further vision loss or permanent effects. In the case of retinal artery obstruction, active vasodilatation therapy is needed to prevent ischemic changes in the retina by reopening the blood vessels. In the case of retinal vein obstruction, no specific treatment is usually required in the early stages, and treatment is considered in the event of complications. Vitreous hemorrhage requires a semi-recumbent position in the early stages to allow the hemorrhage to absorb on its own, and vitrectomy is considered in cases where absorption is not possible. In case of retinal detachment, early surgical treatment is required.