Eye floaters are common visual phenomena that appear as small spots, specks, or thread-like shapes drifting across one’s vision. They are often most noticeable when looking at a plain, bright background, such as a clear sky or a white wall. While generally harmless, these disturbances can sometimes signal a more serious eye condition.
Understanding Eye Floaters
The human eye contains a transparent, gel-like substance known as the vitreous humor, which fills the large central cavity between the lens and the retina. This substance, comprising mostly water, also contains a network of collagen fibers, along with small amounts of salts, sugars, and proteins. The vitreous humor plays a role in maintaining the eye’s spherical shape, absorbing shock, and allowing light to pass unobstructed to the retina.
As a person ages, the vitreous humor undergoes natural changes, a process called vitreous syneresis. During this process, the gel begins to liquefy and shrink, causing the collagen fibers within it to clump together. These tiny clumps or strands then cast shadows onto the retina, the light-sensitive tissue at the back of the eye, which are perceived as floaters. The vitreous gel eventually separates from the retina, a condition known as posterior vitreous detachment (PVD), which is a common cause of new floaters.
When Floaters Typically Emerge
Eye floaters are primarily associated with the natural aging process of the eye. For most individuals, floaters begin to appear between the ages of 50 and 70. The prevalence of posterior vitreous detachment, a common cause of new floaters, significantly increases with age, affecting a large percentage of people over 65. While more common in older adults, floaters are not exclusive to this age group.
Floaters can occur earlier in life due to various factors. People who are nearsighted (myopic) have a higher likelihood of developing floaters because their eyeballs are typically longer, which can lead to earlier vitreous changes. Other contributing factors for earlier onset can include eye injury, inflammation within the eye (uveitis), or complications from certain eye surgeries, such as cataract removal.
Recognizing When Floaters Signal a Problem
Certain symptoms can indicate a more serious underlying eye condition that requires immediate medical attention. A sudden increase in the number or size of floaters is a primary warning sign. This sudden change may also be accompanied by flashes of light, known as photopsias, which appear as brief streaks or sparkles in the vision. These flashes occur when the vitreous gel pulls or rubs on the retina.
Other concerning symptoms include the appearance of a dark curtain or shadow obscuring part of the vision, or any sudden loss of vision. These symptoms can signal a serious problem such as a retinal tear or a retinal detachment, where the retina pulls away from its normal position at the back of the eye. If left untreated, a retinal detachment can lead to permanent vision loss. Therefore, anyone experiencing these specific symptoms should seek prompt evaluation from an eye care professional.