Healthy Vision: What Causes Dark Floaters?

It can be frightening to see tiny specks of flood your field of vision. Those specks are known as eye floaters and a relatively common phenomenon particularly in older people and those who are near-sighted. They are usually dark in color and may resemble black spots. When people experience them, they’re sometimes concerned that they’re having a stroke or have a serious disease. Are dark floaters a cause for concern?

What Causes Eye Floaters?

You may be surprised to learn that eye floaters aren’t an optical illusion. When you see dark floaters you’re seeing actual specks of material suspended in the vitreous humor, the jelly-like fluid that fills the interior of the eye. Sometimes these deposits are remnants remaining from when the eye was formed, but more commonly they represent debris that accumulates over time as the eye ages. This debris can move through the vitreous humor casting a shadow on the retina which makes the debris appear as gray or dark specks in the field of vision. Some people with dark floaters also experience jagged lines, specks, or squiggles of light. Dark floaters are so visible, and annoying, because they’re suspended in a liquid media and can move across the retinal field.

Are White Floaters a Sign of a More Serious Problem?

In most cases, eye floaters are not a sign of disease or serious illness. In rare cases, they can indicate a retinal detachment or tear. With a retinal tear or detachment, red blood cells leak out of vessels into the vitreous humor causing the appearance of large numbers of floaters along with flashes of light, and decreased vision. Usually floaters related to a retinal detachment appear suddenly with little warning. This is a true medical emergency that needs immediate treatment to save vision. The sudden appearance of large numbers of floaters should always be seen by a doctor.

There are a few other eye problems that can cause floaters, but most dark floaters are merely an annoyance without any real significance in terms of overall health. New onset floaters and floaters associated with other symptoms such as blurred vision, eye pain, or double vision, should be evaluated by an eye doctor to rule out underlying eye problems. Serious causes of floaters can usually be ruled out with a dilated eye exam to more closely examine the back of the eye, or retina.

What Can You Do About White Floaters?

Unfortunately, there’s not a lot you can do about floaters with the exception of a surgery known as a vitrectomy which has a high complication rate. This is usually reserved for severe cases. The good news is, the dark floaters may come and go or become less bothersome over time. Most people are able to adjust to this problem once they’re reassured that they aren’t serious.

References:

Merck Manual of Medicine