What are Eye Floaters?

What are Eye Floaters?

Every weekday, a CNNHealth expert doctor answers a viewer question. On Mondays, it's pediatrician Dr. Jennifer Shu.

Asked by Paul from New York

I'm 39 years old and have had a few floaters in both eyes for as long as I can remember. I go to the eye doctor every year for my glasses but forget to ask about these floaters. What causes them? Do I need to worry?

Expert answer

Thanks for your question. Floaters, or little spots or thread-like objects, can be seen particularly well if your eyes are moving and looking at something bright, such as a page on a computer screen or a blue sky.

Most of the time, they do not cause any problems. For more details, I consulted Dr. Ravi Goel, a board-certified ophthalmologist at Regional Eye Associates in Cherry Hill, New Jersey, and an instructor with the Wills Eye Institute Cataract and Primary Eye Care Service in Philadelphia.

Goel describes the following analogy about floaters: Imagine the central part of the eye (the vitreous gel) as being a solid ball of ice or solid clear gelatinous material when you're born.

As you grow older, that ball of ice starts to turn into a liquid and starts to pull on the retina, the innermost part of the back of the eyeball. This process can lead to flashes (from the tugging of the gel-like material along the nerve layer of the retina) or floaters (cells that float in the central part of the eye and are seen by the central retina, called the macula).

Flashes and floaters may also be a sign of an ophthalmic migraine, which Goel says is similar to an aura of a migraine headache but without the pain.

The retina examination can be completely normal and ophthalmologists will send patients for a medical evaluation. Patients are typically evaluated for underlying headache, which may include cardiac and carotid evaluation.

If the gel-like material tugs too hard, there may be a sudden shower of floaters, which is a sign of a possible retinal detachment. This can happen in patients who have had recent trauma or surgery, are nearsighted (myopic), or who have sudden loss of central or peripheral vision, flashes or hazy vision.

These patients should be evaluated immediately. Goel recommends that anyone with floaters receive an initial ophthalmic consultation that includes pupil dilation - an evaluation that it sounds like you have already had.

Patients should review their symptoms and also possible triggers (such as coffee, chocolate and stress) that might suggest a migraine. It can be helpful to keep a journal of repeat episodes.

When a floater-like episode begins, Goel suggests immediately covering each eye to determine if it occurs in one eye or both, and documenting the time of day, activity and possible stressing events.

If you have any of the concerning symptoms or have further questions, be sure to consult your ophthalmologist. Good luck!