Floaters: Causes, Symptoms, and Treatments

Floaters appear as small gray or black dots, lines, or “cobweb-like” strands in front of the eyes. As your eyes move, floaters also shift. However, they do not precisely follow your eye movements, as they typically drift when the eyes start or stop moving.

Floaters are caused by small clumps of material suspended in the vitreous gel (known as the vitreous humour) that fills the back of the eye. These floaters cast shadows on the light-sensitive retina, which is what you actually see. Floaters can have a variety of causes—some serious, some not.

Many people have floaters. Floaters that have been present for years and remain stable are usually not a concern. However, the sudden onset of one or multiple large floaters may indicate a more serious issue.

Anyone experiencing floaters should be examined promptly by an optometrist. The optometrist will perform a dilated eye exam, using specialized equipment to examine the vitreous and retina after administering eye drops to enlarge the pupils.

Your optometrist will examine the inside of your eye for signs of disease or damage to the vitreous or retina. The sudden onset of floaters or flashes is often caused by a separation of the vitreous from the retina. When this occurs, the retina may tear or detach in approximately 10% of cases. In most cases, the retina remains intact, and your optometrist will schedule a follow-up exam at a later date.

In most cases, floaters gradually diminish over weeks or months. However, they often do not disappear completely. Most people learn to ignore them. Floaters, like flashes, may subside even if a retinal tear or detachment is present. Once again, you should undergo an eye exam even if floaters seem to fade. If a retinal tear or detachment is detected, your optometrist will discuss treatment options with you.