This Saturday is World Stroke Day. In France, healthcare professionals have chosen to focus this year on a largely misunderstood pathology: stroke of the eye, more precisely called central retinal artery occlusion (ROAC). What is it about ? The point with a specialist, Benoît Guillon, neurologist at the University Hospital of Nantes, hospital who decided to launch an awareness campaign on the subject.
What exactly is an eye stroke?
Like the brain stroke, it is an accident of the carotid artery with the displacement of a blood clot. Except that this clot will not go up to the brain but migrate to the eye where it will obstruct blood circulation. This will be manifested by a sudden and total loss of vision in that eye. It lasts a few seconds with, sometimes, the feeling of a veil falling. It is, in addition, completely painless and is not accompanied by redness.
How can I be sure it’s not another problem?
This sudden, painless blindness is a specific symptom of eye stroke. There are other causes of blindness, such as acute glaucoma, retinal detachment or hemorrhage, but they are accompanied by pain or redness. Either way, you need to see an ophthalmologist urgently. And as it is complicated to get an appointment quickly, we recommend calling the Samu (15) who will direct you to the right sector.
Can we wait until the next day and hope that the situation improves?
Especially not. Because one of the medical responses, currently being studied, consists in trying to unclog the blood circulation by injecting a drug treatment which aims to dissolve the blood clot. But for the cells of the retina to be able to function again, it is necessary to intervene as quickly as possible, four to five hours maximum after the accident. After this time, the damage is very often irreversible.
So what if we react too late?
There is still a need for medical vigilance because approximately 10% to 15% of people who have an eye stroke will have a brain stroke in the days that follow. Appropriate medical examinations are therefore necessary. Treatment with aspirin, as for ischemic strokes, will reduce the risk of recurrence.
Which people are at risk for strokes of the eye?
Anyone can be affected, with risk factors that are the same as for brain stroke: high blood pressure, diabetes, cholesterol, tobacco and cardiac arrhythmia. Age is also a factor since the majority of cases concern people over 65 years of age. The vascular accident of the eye is however rarer than that of the brain. It is difficult to estimate how many people are affected, perhaps between 5,000 and 10,000 per year. Blindness in one eye is a lesser handicap than hemiplegia but, in the elderly, it can cause a loss of autonomy.
How to fight against this phenomenon?
It is important to learn to spot the symptoms and to react quickly by calling 15. Often, what we observe is that, through ignorance, patients minimize the situation by telling themselves that it is temporary. They wait and start to worry after several hours. But a waste of time is a waste of opportunity. In some cases, the vision returns gradually but it is still necessary to consult because it may be a transient vascular accident signaling a significant risk of occurrence of a stroke.