Eye floaters are small moving spots that appear in your field of vision. They can sometimes appear like squiggly lines or black or gray dots, or even have a ring or cobweb shape. They are usually caused by a protein called collagen (you wouldn't want to inject this collagen into your lips, though … not that I’m judging).

Behind the eye is a gel-like substance called vitreous humor, often referred to as simply "vitreous." Made up of collagen, the substance starts to break into fine shreds as we age, building up in the vitreous and changing the way light hits our retina. Because of this change, eye floaters may appear. That’s why eye floaters most commonly occur in people ages 50-75. They are also more common in people with nearsighted vision. (I have it on good authority that they look very much like the photo below.)

eye floatersThough they can be very annoying, eye floaters are generally benign and don’t require medical treatment. When this is the case, flicking your eyes up and down or side to side helps to move them out of your field of vision since this causes the fluid in the back of your eyes to move. Eye floaters can become less noticeable over the course of months or years, but once you have them, you generally have them forever.

Once in a while, an eye doctor will consider a surgical procedure called a vitrectomy if the floaters are so numerous or dense that they seriously affect the patient’s vision. During a vitrectomy, all of the vitreous and floating debris are removed and replaced with a salt solution. There are high risks associated with the procedure, including retinal detachment and cataracts. Another treatment for eye floaters is laser therapy, in which a laser is pointed at the fine shreds in the vitreous in an attempt to break them up. Some report improved vision after laser therapy, but it’s largely experimental and many eye doctors will not perform the procedure. The procedure also comes with risks, as damage to the retina can occur from the laser being pointed incorrectly.

Usually eye floaters are nothing more than annoying. But sometimes they do require urgent medical treatment. If they come on suddenly or increase in number very quickly, it could be a symptom of an underlying condition. Likewise, if the floaters are accompanied with cloudy or blurred vision, pain or flashes of light, something serious could be underfoot (or under eye, as it were). What exactly? Floaters such as these could be a symptom of a retinal tear or retinal detachment that requires immediate medical attention since it could cause permanent vision loss. They could also be a symptom of bleeding within the eye or eye tumors.

Though there’s not much you can do about eye floaters once they do appear, there are some things you can do to protect your eye health as you age. First, make sure you have a comprehensive eye exam (in which your eyes are dilated) once a year to detect any possible vision problems. The earlier detection and treatment occurs, the more likely you can prevent permanent vision loss. Also, wear protective eyewear — this means wearing sunglasses that protect you from UVA rays when you’re outside and also wearing goggles when you’re doing tasks that can cause debris or worse to get in your eye. Finally, prevent eyestrain by blinking and looking away from the screen every so often, especially when you’re at the computer.

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Floaters photo: Wikimedia Commons