Specks, squiggles or bright flashes in your field of vision are also called flashes and floaters. Unless of course, you’re watching your neighbor’s Christmas light display. You know the one I mean. It starts every year just after Thanksgiving night and has caused a power grid brown-out nearly every evening when it gets turned on; the same one that he got a warning from the FAA for last year because it caused aircraft to divert from the active runway at the airport.
Usually the flashes and floaters come and go quickly, are quite common and more often than not harmless to your vision. Floaters can look like little bugs, stars, threads, or cobwebs. They move when you try to look at them and are most noticeable under high contrast situations such as a light shining off a white page or the sun shining off the snow. Flashes look like streaks of lightening or flashing lights in your side vision.
The vitreous is a gel that fills most of the eye. With aging or after an injury to the eye the vitreous will start to liquefy much like a Jell-O mold left out in the hot sun. When this occurs, the vitreous starts to shrink and pull away from the inside walls of the eye. This causes the fibers in the gel to start to knot or clump up. That is how the floaters typically form. If the vitreous tugs on the retina while it is shrinking the retina is stimulated and you will see flashes of light. As the vitreous finishes detaching from the eye the flashes will become less frequent until they no longer occur. This may take several months to happen. The floaters will always be there but over time your eyes will get us to them and they will seem to disappear most of the time. Since floaters are harmless and only an annoyance and because any treatment could cause more problems than they correct there is no need to treat them.
Rarely the vitreous will tug hard enough on the retina to cause a tear or hole to form in the retina. If this happens fluid can get behind the retina causing a retinal detachment. This is a serious eye condition and requires immediate attention and treatment. Signs of a tear in the retina may include a sudden increase in the number and shape of the floaters or increase in the number or brightness of flashes. Additionally you may experience what appears to be a curtain covering part of the vision. A retinal tear is painless so you won’t feel it when it happens but it must be treated early to protect your vision. In many cases applying laser to the area around the tear can fix the tear. In more serious cases various types of surgery may be required.
Diabetics with diabetic eye disease have a higher risk of developing serious retinal problems. Many times the sudden increase in the number of floaters is caused by bleeding from abnormal or weakened blood vessels in the eye. The retinal detachments that can form in diabetics are also more difficult to treat because of the scar tissue that forms in these eyes.
If you notice any of these signs or symptoms it is important to call your eye physician for an appointment as soon as possible. It is never wise to assume that the problem will go away if you just ignore it. In most cases the vitreous is just undergoing the natural changes of age and a little reassurance is all that is needed. In the rare case where the retina is torn early treatment can make all the difference.
(Editor’s note: If you have questions about your eye health e-mail Dr. Barowsky at firstname.lastname@example.org and we’ll try to answer your questions here at Eye-Q.)