Have you ever seen a speck or thread-like strand float across your field of vision? Many times these spots or floaters in your eyes are just an irritating consequence of aging. However, if these symptoms are new or get worse, it’s time to call your eye doctor. Read more about the symptoms, causes, and management of this common eye condition.
What are eye spots, flashes, and floaters?
Floaters are transparent spots, specks, or lines that seem to move or "float" across your field of vision. They are actually small, semi-transparent, or cloudy particles within the vitreous (the jelly-like fluid filling the back of the eye). They come in different shapes and sizes and can look like insects, raindrops, dark spots, cobwebs, thread-like strands, or hair. Some move around more and others seems to be much less mobile.
What causes spots and floaters?
Floaters are flecks of protein or other matter trapped in the back cavity of the eye. New or large floaters are frequently caused when the vitreous gel detaches from the back wall of the eyeball. Although this sounds a bit scary, this typically happens as part of the normal aging process. Certain eye diseases or injuries can also cause floaters.
Are spots and floaters serious?
Most spots and floaters are normal, but sometimes they can indicate a more serious problem, especially if there is a sudden increase in their number or if they are accompanied by flashes of light.
What are the flashes?
Flashes are brief, lightning-like streaks or arcs of light seen in your side, or peripheral, vision that may or may not appear with spots and floaters. They are similar to what you see when a flash goes off on a camera. Each flash only lasts for a split second. They are typically white and are more visible in the dark. Flashes occur when the vitreous gel tugs on and pulls away from the retina (the back lining of the eye like the film in the back of a camera that receives visual images and sends them to the brain). Every time the vitreous pulls on the retina, you will see a flash of light. After the vitreous completely separates, flashes tend to become less prominent and usually completely stop over a period of several weeks.
Another cause of flashes might be migraines. Flashes related to migraines usually last for about 15-30 minutes, tend to be colorful, shimmering, appear in both eyes simultaneously, and may slowly move across your vision. They then completely stop and may or may not be followed by a headache.
Is a vitreous detachment serious?
Vitreous detachment is very common. The vitreous detaches over several weeks, and the floaters and flashes tend to become less prominent. Sometimes, however, a vitreous detachment can cause tears in the retina. These tears can progress and cause vision loss if left untreated.
What should I do if I see spots, floaters, or flashes?
If you suddenly see new spots, floaters, or flashes, if they get worse, or if you see a dark curtain progressing over your side vision, you should contact your eye doctor immediately. You will need a dilated examination. Drops are used to make the pupil larger so the doctor can see the entire retina. The dilated exam will make your eyes light sensitive and your vision blurry for several hours. This examination allows your eye doctor to determine if you have a vitreous detachment or a more serious problem like a retinal tear or retinal detachment.
In most cases, a sudden increase in spots, floaters, or flashes requires no treatment other than careful monitoring by your eye doctor. However, a dilated exam is extremely important to make sure it is a vitreous detachment and not a more serious problem such as a retinal tear or retinal detachment which must be treated quickly.
Updated October 2022
About The Author
Vandhana Sharda, OD, MS, FAAO
Dr. Vandhana Sharda joined Atrius Health in 2013 as chief of optometry. She received her degree from the New England College of Optometry in Boston, where she later served as clinical faculty while completing her research on myopia development in the chick model. Dr. Sharda sees patients at our Kenmore and Medford practices.