Who is at risk?

Flashes and floaters are very common. Almost everyone experiences them at one time or another. They become more frequent as we age. In rare cases, a doctor’s exam may reveal a more serious problem called a retinal tear or retinal hole. Hence, it’s important to get regular eye exams and inform your doctor if you’re experiencing flashes or floaters.

Causes of flashes and floaters

Most flashes and floaters are caused by age-related changes in the gel-like material, called vitreous, that fills the back of the eye. When you are born, the vitreous is firmly attached to the retina. In the very young, the vitreous is rather thick, like firm gelatin. Within the vitreous, there may be clumps of gel or tiny strands of tissue debris leftover from the eye’s early development. These clumps or strands are firmly embedded in the thick, young vitreous and cannot move around much.

As you get older, the vitreous gradually becomes thinner or more watery. By the time you are in your twenties or thirties, the vitreous may be watery enough to allow some of the clumps and strands to move around inside the eye. This material floating inside the eye can cast shadows on the retina, which you see as small floating spots.

Sometime after about age 55, you may experience the onset of larger, more bothersome floaters or flashes of light. By this age, the vitreous gel has usually become much more watery. It jiggles around quite a bit when you move your eye, making flashes and floaters much more common.

Eventually, the aging vitreous can pull away from the retina and shrink into a dense mass of gel in the middle of the eyeball. Shadows cast onto the retina by the detached vitreous can cause you to see large floaters.