Sudden blindness or severe vision loss in one eye is a medical emergency. Several sight-threatening conditions can cause it.
Vascular and retinal causes
Blocked blood vessels at the retina or optic nerve stop oxygen reaching vital tissues. Vision may go dark or very blurred within seconds.
- Central retinal artery occlusion often causes profound, painless loss
- Central retinal vein occlusion may cause sudden, hazy vision
- Retinal detachment can produce rapid loss with floaters and flashes
- Eye strokes are linked with cardiovascular risk factors
Other urgent causes
Severe optic nerve inflammation, acute glaucoma, or trauma can also lead to sudden blindness. Fast treatment offers the best chance of recovery.
- Optic neuritis may cause pain on eye movements and colour desaturation
- Acute angle-closure glaucoma causes intense pain, haloes, and nausea
- Penetrating injuries can instantly destroy retinal function
- Emergency hospital assessment should never be delayed
