Sudden and painless vision loss in the elderly should be alerted to central retinal artery blockage: Many elderly people do not take vision loss seriously and feel that it is normal to have poor vision as they get older. However, if the vision loss is sudden and significant, even to the point of not being able to see, it is important to go to the hospital as soon as possible. Because some diseases start rapidly and progress quickly, if not treated in time, the best treatment time will be lost and permanent vision loss may result. Since the central retinal artery is one of the main blood vessels supplying the retina, blockage of the central retinal artery will lead to retinal ischemia and hypoxia, resulting in retinal edema (Figure 1 is the normal fundus; Figure 2 is the fundus of the central retinal artery: the retina becomes “anemic” in appearance), resulting in a dramatic decrease in visual transmission function. This leads to a dramatic decrease in visual transmission. Therefore, if the vision loss is painless, be alert to the occurrence of central retinal artery obstruction. Common clinical risk factors for central retinal artery obstruction include: hypertension, atherosclerosis, and other common age-related diseases; inflammation of the central retinal artery; obstruction of the central retinal artery caused by emboli (e.g., cholesterol emboli, blood clots, etc.) shed from other parts of the body and carried by blood flow to the central retinal artery; and high intraocular pressure in glaucoma, which compresses the wall of the eye from the inside, orbital tumors or hematomas that compress the blood vessels from the outside. In addition, high intraocular pressure in glaucoma can compress the wall of the eye from inside the eye, orbital tumors or hematomas can compress the wall of the eye from outside the eye, resulting in vascular compression. The main manifestations of central retinal artery occlusion include sudden and painless loss of vision in the affected eye, without eye pain, photophobia, redness, tearing and other eye discomfort. Some patients have a history of paroxysmal black dawn before vision loss. Figure 1. Normal fundus Figure 2: Fundus of central retinal artery occlusion