What to know about eye floaters and flashes

Most people will experience eye floaters in their lifetime, especially as they get older. They’re those tiny spots or lines that look like they’re in front of the eye, but they are actually

floating inside it. Flashes, which look like streaks of lightning, are more common with age, too. Most of the time, neither floaters nor flashes are cause for worry. But under certain

circumstances, they require immediate medical attention. Here’s what you need to know to protect your vision. WHAT THEY ARE Floaters can be disconcerting. “They can appear as rings, whips,

sheets, squiggles or other patterns,” says Ming Wang, M.D., founding director of Wang Vision 3D Cataract and LASIK Center in Nashville, Tenn. Sometimes they’re in the peripheral vision,

other times they’re at the center, or both. Floaters tend to move as the eye moves — for example, moving up when the eye moves up and settling downward when the eyes are still. They’re

easier to see on a uniform background (a white wall or a blue sky), or after doing activities that require frequent and quick side-to-side or up-and-down movements, such as driving or

reading. Flashes are different. Wang describes them as “split-second bright white disturbances in the vision” that people often describe as a lightning bolt. They can look like arcs or small

streaks, and come and go very quickly, sometimes just at the corner of the eye. They’re more noticeable in the dark, so people may not be aware of them during the day. CAUSES Most of the

time, both floaters and flashes are due to normal age-related changes in the vitreous, the gel structure that fills the back of the eye and keeps the eye round. When we're young, the

vitreous has a gel-like consistency. Later it becomes more liquid, Wang says, and “strands form together and move through the light pathway in front of the retina.” These are perceived as

floating spots, and many people just learn to live with them.   The occurrence of flashes is related to the interaction of the vitreous with the retina. “At younger ages, the vitreous is

fully adhered to the retina,” Wang says. “As the vitreous begins to separate from the retina, it can pull on it slightly.” This produces the appearance of a flash in the vision — “as you

would see from a camera,” explains Sean Ianchulev, M.D., professor of ophthalmology at the Icahn School of Medicine at Mount Sinai in New York City. Because the pulling force is quick and

fleeting, the flash will last only a split second.