Vision loss is the most common symptom in clinical ophthalmology diseases. The classification is different and the causes of vision loss are different, mainly divided into the following categories: 1, transient vision loss: common causes are optic papilloedema (lasts for several seconds, often occurs in both eyes), transient ischemic attack (lasts for several minutes, often occurs in one eye), excessive fatigue, hunger, mental stimulation (relieved after rest and diet). (1) Sudden, painless vision loss: retinal artery or vein blockage, ischemic optic neuropathy, vitreous hemorrhage, retinal detachment, optic neuritis, methanol poisoning, central nervous system disease (e.g., stroke), etc. (2) Chronic painless vision loss (weeks, months or years): cataract, refractive error, open-angle glaucoma, chronic closed-angle glaucoma, age-related macular degeneration, diabetic retinopathy, corneal dystrophy, optic nerve atrophy, etc. (3) Painful vision loss: acute closed-angle glaucoma, optic neuritis (painful eye rotation), uveitis, endophthalmitis, corneal edema (cone cornea), etc. 3, loss of vision after trauma: eyelid edema, corneal irregularity, corneal edema, eye rupture, traumatic cataract, lens dislocation, retinal concussion, retinal detachment, retinal hemorrhage or vitreous hemorrhage, traumatic optic neuropathy, cerebral neuropathy, central nervous system injury. Therefore, there are many causes of vision loss. When vision loss is not relieved after rest or diet, prompt medical attention is required.