Damage to the retina
The retina is the focusing surface at the back of your eye. Any damage to your retina, such as a detached retina or artery occlusion, is a possible cause of sudden blindness.
A detached retina can cause total loss of vision in the affected eye, or it may only result in partial vision loss, making it seem as if a curtain is blocking part of your vision.
The macula is the central focusing area of the retina at the back of your eye. When a macular problem occurs, it results in a loss of your central vision, while your peripheral or ‘side’ vision remains.
Some eye conditions can cause blood to leak into the vitreous ‘gel’ within the eye. This is known as a vitreous haemorrhage. If this occurs, it can block the light which enters the eye, causing sudden blurred vision if it is not as dense, or the sudden appearance of spots within your vision.
Serious medical conditions
There are some serious medical conditions that can cause sudden blindness, such as a stroke or brain tumour. While these causes are quite rare, it is nonetheless important to seek medical attention as soon as possible.