List six causes of sudden loss of vision?

1. Retinal detachment: This occurs when the retina, the light-sensitive tissue at the back of the eye, becomes separated from its normal position. It can cause sudden and severe vision loss.

2. Macular degeneration: This is a chronic eye disease that affects the macula, the central part of the retina responsible for sharp, central vision. Sudden vision loss can occur if there is a sudden bleeding or fluid accumulation in the macula.

3. Stroke: A stroke occurs when the blood supply to the brain is interrupted, leading to damage in the affected area. If the stroke affects the part of the brain responsible for vision, sudden loss of vision can occur.

4. Acute angle-closure glaucoma: This is a medical emergency where the pressure inside the eye increases rapidly due to a blockage of fluid drainage. It can cause sudden vision loss, along with symptoms like severe eye pain, headache, and nausea.

5. Optic neuritis: This is the inflammation of the optic nerve, which transmits visual information from the eye to the brain. It can cause sudden vision loss, along with pain and changes in color perception.

6. Retinal artery occlusion: This occurs when the blood flow to the retina is blocked, usually due to a blood clot. It can cause sudden and painless vision loss in one eye.