A sudden loss of vision in one eye, even without pain, can indicate an eye stroke. This is a medical emergency that should never be ignored.
A sudden loss of vision in one eye, without any pain, may seem surprising. However, this symptom is far from harmless. Often overlooked, an eye stroke is a genuine medical emergency that can lead to irreversible vision loss if treatment is delayed. Here are the signs to recognize and the right steps to take.
A stroke can also affect the eye
An eye stroke, also called a retinal artery or vein occlusion, occurs when blood flow is suddenly interrupted in the vessels of the retina. This interruption is usually caused by a blood clot or a significant decrease in oxygen supply. As with a cerebral stroke, every minute counts, because the retina is particularly sensitive to oxygen deprivation.
There are several forms of eye stroke, the consequences of which vary depending on the vessel involved.
The most serious type is central retinal artery occlusion. Often compared to a heart attack, it occurs when the main artery supplying blood to the retina suddenly becomes blocked. The result is a sudden, painless, and almost total loss of vision in one eye. Vision becomes extremely blurry or disappears completely. Without rapid restoration of blood flow, the damage can become irreversible in just a few hours.
The most common form is central retinal vein occlusion. In this case, it is the drainage of blood that is disrupted. The decrease in vision can appear suddenly or more gradually. It is sometimes less severe than in the arterial form, but it remains serious. It can be accompanied by retinal hemorrhages and edema that can lead to lasting damage.
Finally, some occlusions only affect one arterial or venous branch. These cause the loss of part of the visual field, creating a blind spot called a scotoma.
