Sudden deterioration of vision is commonly seen in clinical conditions such as transient vision loss, vitreous hemorrhage, ocular inflammation, glaucoma, retinopathy, intracranial tumors, and ocular trauma. 1. Transient vision loss. This is often caused by insufficient blood supply to the vertebral basilar artery or a transient ischemic attack. 2. Vitreous hemorrhage. Often caused by retinal hemorrhage due to trauma, retinopathy, etc. Blood breaks through the inner border membrane and enters the vitreous cavity. 3. Ocular inflammation. Keratitis, uveitis and other lesions can cause sudden loss of vision. 4. Acute attack of glaucoma. When the intraocular pressure rises sharply, it can lead to a sudden loss of vision. 5. Retinopathy. Sudden loss of vision can be caused by hemorrhage, edema, atrophy, detachment of retina due to systemic diseases such as diabetes mellitus, hypertension, etc., or local lesions in the eye. 6. Intracranial tumor. When the tumor compresses the optic nerve, it will cause damage to the optic nerve and sudden vision loss. 7. Eye trauma. Localized trauma to the eye may cause damage to the refractive medium of the eye, resulting in sudden vision loss. It is recommended to go to the hospital as soon as possible to consult the doctor to find out the cause of the sudden vision loss and follow the doctor’s instructions.