These are termed Hollenhorst plaques. They are made up of cholesterol that became lodged in one of the retinal blood vessels (the retina is the back of the eye). The cholesterol comes from a blood vessel that supplies blood to the eyes. Most often, cholesterol plaques can be found in the internal carotid arteries, located in the neck.
When Hollenhorst plaques are seen, the ophthalmologist should ask for a complete physical exam including blood work to check cholesterol levels and a carotid doppler. Carotid doppler is an ultrasound used to look for cholesterol plaques in the internal carotid arteries.
Hollenhorst plaques can cause a decrease in blood flow to certain areas of the eye and ultimately can affect vision permanently. This is the reason that the above testing and proper cholesterol control is quite important.
I hope this is helpful...