Patients with a retinal artery occlusion can be at great risk for having a heart attack and/or stroke. Just as the artery in the eye gets blocked, so too can an artery in the brain or heart. Assessing the heart and major arteries for disease can prevent this from occurring.
Blood leaves the heart via the aorta and then enters the carotid arteries (large vessels that send blood to your head). The central retinal artery supplies all the blood to the retina.
In both a central retinal artery occlusion (CRAO) and a branch retinal artery occlusion (BRAO), the blood vessels becomes blocked, blood flow is stopped and permanent vision loss can occur.
Vision loss is usually sudden and painless. It can be complete and permanent. Sometimes the blockage is temporary and vision is restored after 15-20 minutes. This phenomenon is called “amaurosis fugax.”
Partial loss of sight may occur from a branch artery occlusion where a small portion of the retinal circulation is blocked.
The usual culprit in retinal occlusions is a small piece of cholesterol from the carotid arteries. The actual blockage can be seen when looking directly at the retina. This is best done by having your pupils dilated. A flourescein angiogram may be helpful, too.
Other causes include blood clots or high levels of fats in your blood.
Nothing can be done for your vision when an artery occlusion occurs. Your doctor needs to be on the look out for neovascularization to occur somewhere in your eye. This could cause a painful type of glaucoma. Neovascular glaucoma can be prevented.
Most importantly, your doctor needs to order tests looking for the source of the clots or plaque. This usually entails evaluation of the heart with an echocardiogram and an ultrasound of the carotid arteries. Other tests may be needed.
Patients with diabetes and high blood pressure are at greater risk for these conditions. Also, atrial fibrillation (heart rhythm disorder) and disorders with high blood fats can cause artery occlusions.
What Does This Mean? This is one of the few instances where your eye doctor could literally save your life. While there is really nothing we can do to improve your vision, we can make sure that you are not at risk for a heart attack or stroke.
Sudden painless loss of vision should be evaluated even if your vision returns to normal. While there are other causes of these symptoms, you should be evaluated for systemic disease.
Even if you are not diabetic or do not have high blood pressure, make sure to alert your doctor.