Have you ever thought you saw something drifting across your vision, only to realize that the something you saw was not there at all? You probably saw a "floater." Though sometimes quite annoying, floaters usually aren't harmful. Nevertheless, keep an eye out for any sudden change, as it could be a sign of something more serious.
Floaters, medically called myodesopsia, are tiny pieces of debris that clump in the clear jelly-like vitreous fluid that fills the back of your eyeball. When light hits the debris, it casts a shadow on the retina that may look like a fly or spider web in your vision. These shadows move as the vitreous jelly drifts about and tend to be more obvious when looking at white backgrounds like a book or wall. Most everyone will experience floaters if they live long enough. Unfortunately, once a floater appears, it usually will not go away.
As you age, the vitreous jelly shrinks and pulls away from the retina, a thin layer of tissue that lines the back of your eye, much like film in a camera. This process, called posterior vitreous detachment, can cause proteins to clump within the vitreous or pull fibers away from the retina the way ink can be lifted off a wet newspaper page. Although usually harmless, a very small number of cases turn out to be something serious.
What makes eye floaters worrisome is that they may represent the beginning of a retinal detachment. Without treatment, retinal detachment can lead to permanent vision loss in the affected eye.
Most people over 50 years of age have a few floaters moving around inside the eye. See an ophthalmologist immediately if you notice any of the following:
- A sudden increase in the number or size of floaters
- Flashing lights
- Partial loss of vision, like a curtain or veil is covering part of your eye
These symptoms could mean that the retina is detaching from the back of the eye, cutting off blood and oxygen. This condition requires urgent attention.
Floaters come with age, but young people can experience them as well. Causes other than age include eye trauma, cataract surgery, nearsightedness and diabetic retinopathy. There is no magic eye drop or therapy to get rid of floaters, but over time, they usually become less bothersome. Floaters tend to settle towards the bottom of the vitreous fluid, often out of your field of vision.
There is a surgical procedure to replace the vitreous fluid with a saltwater solution. It's called a vitrectomy. However, this procedure is rarely recommended for ordinary floaters because it carries its own risks like infection, retinal tears and cataract formation.
If you notice new floaters or a change in your floaters, an ophthalmologist should examine your eyes for danger signs like a minor retinal tear or traction. Early diagnosis can prevent serious problems down the road. Tears can be sealed with a laser or freezing probe that scars the retina to the underlying tissue to prevent further tearing.
If you only experience the occasional floater, it's best to learn to live with them. However, don’t hesitate to consult with your regular health care provider or an ophthalmologist if you have any sudden changes in vision.
Dr. Beadles is an ophthalmologist for the county health department.
Healthy Outlook is written by the professional staff of Contra Costa Health Services, the county health department. Send questions to series coordinator Dr. David Pepper at firstname.lastname@example.org. For more health information, go to www.cchealth.org.