Floaters and Flashers

What are floaters? People often describe floaters as little dots or lines that appear in their vision.  They can be black, gray, or nearly clear.  They slowly drift across your vision, and move wherever you look.  Looking at light colored backgrounds or at the blue sky makes them easier to see.  These are caused by opacites within the central space of the eye, called the vitreous.  Vitreous is the clear, gel like substance that fills the eye.

Opacities in the vitreous can be caused by the normal aging process of the vitreous, called syneresis. This is due to the gradual loss of water content of the vitreous, which causes the normally clear vitreous to clump together. These clumps can partially block light, and cast a tiny shadow in the eye. You may see this shadow as a floater. Near sighted people tend to develop syneresis at an earlier age and often see a small number of floaters.

However there are much more serious problems that can also cause floaters. Bleeding from diabetic damage to blood vessels in the eye, debris related to a retinal detachment, infections inside the eye, and autoimmune inflammatory diseases of the eye are a few of the serious problems that can cause large numbers of floaters. Many of these diseases, if left untreated, carry the risk of blindness. It is very important to let your eye doctor know if you notice new floaters, or a change in the number of floaters.

What are flashers?
A flasher is a sudden, brief flash of light in your vision that does not come from an actual light source. People often describe them as lightning flashes, strobe lights, arcs of light, or streaks of light. They may also appear repeatedly. Flashers are usually from some sort of stimulation to the retina. The retina is the very thin, delicate lining to the inside of your eye. It is the most important part of the eye for vision.

Sometimes the vitreous in your eye can pull on the retina and cause flashers. This usually occurs with something called a posterior vitreous detachment. A posterior vitreous detachment occurs when the vitreous shrinks from the normal process of syneresis, and then rather quickly separates from the retina. This event creates traction on the retina, and commonly causes flashers and new floaters. If there is enough traction, the retina can be torn. If this tear enlarges, the entire retina can separate from the wall of the eye. This is called a retinal detachment, and if not repaired, causes blindness. A retinal detachment can also cause a dark curtain or veil to come across your vision. If diagnosed early, a retinal tear can often be treated with a laser, while a retinal detachment requires surgical repair.

The appearance of new floaters, flashers, or a curtain are signs of a potentially serious problem, and you should call your doctor promptly.