To Your Health

A. Floaters are bits of debris in the vitreous (the clear material that fills the eyeball) large enough to be seen as a tiny dark speck in your field of vision when you look at a piece of white paper, a blue sky, or any other uninterrupted, light-colored area. They may be relatively transparent but cast a shadow on the retina that looks like cobwebs, strings, rings, or specks. Eye movement usually makes floaters more visible as they swirl about in the vitreous, and the closer they are to the retina the bigger they appear.

They come and go without treatment and more than 70% of the population will experience this problem.

Some floaters are red blood cells or blood clots. Such blood cells would occur with a retinal tear but do not necessarily indicate a tear. Flashes of light followed by a sudden onset of many new floaters should be evaluated by your ophthalmologist. Occasionally, floaters result from inflammation within the eye or from crystalline deposits that form in the vitreous. Only an ophthalmologist can determine whether floaters are serious or not.

More commonly floaters are normal and harmless, caused by a clumping of pre-existing particles left in the vitreous after the growth of the eye was completed. The vitreous in children is very firm, like jelly. In older folks the vitreous thins and becomes watery. Floaters tend to become more abundant with age, because the vitreous separates from the retina, creating small shreds of debris.

Floaters are suspended in the vitreous, which means they move around some. Floaters in your peripheral vision tend to go unnoticed, but sometimes floaters can interfere with reading. If so, try looking up and down, and from side to side, to swish the vitreous and move the floater out of the way. Or, you may find that over time your brain becomes accustomed to floaters and may decide not to "inform" you of their presence. Surgery to remove a floater has a 98% success rate but is done very rarely. It is sort of like killing a gnat with a sledgehammer.

Some people claim that the same nutrients that are well documented to prevent age-related macular degeneration have also reduced the number of their floaters, but there is no solid research to back this up. Most people find these nutrients do not affect their floaters, although they may find benefits unrelated to eyes (better sleep, fewer headaches, etc.). The nutrients most commonly tried are vitamin A and its relatives (lutein, zeaxanthin, alpha- and beta-carotene, etc), vitamin C, vitamin E, zinc, selenium, and alpha lipoic acid. These are all antioxidants, often insufficient in the American diet, and safe to try for a few months at the level you would find in the formulas designed to prevent AMD. The herbal remedies – bilberry, eyebright, and many others – are often rich in these same nutrients.

Occasional floaters are nothing to worry about. Most go away over time as the chunks settle to the bottom of the eye or your brain learns to simply ignore them. If you suddenly see a large number of floaters and flashes of light, consult your ophthalmologist immediately. Delaying treatment might have serious consequences.