Eye floaters are a common visual experience, appearing as small specks, threads, or cobwebs that drift across one’s field of vision.
Understanding Eye Floaters
Eye floaters are tiny clumps of cells or protein within the vitreous humor, the jelly-like substance that fills the space between the eye’s lens and retina. As light enters the eye, these clumps cast shadows onto the retina, which are then perceived as floaters. Floaters can appear in various forms, such as small black dots, squiggly lines, or cobweb shapes.
The vitreous humor is primarily composed of water and collagen fibers. As a natural part of aging, typically after age 50, the vitreous can liquify and contract, a process known as vitreous syneresis. This change causes the microscopic collagen fibers to clump together, leading to the formation of floaters. While floaters are generally harmless and often become less noticeable over time as the brain adapts, they can sometimes indicate more serious eye conditions.
The Connection Between COVID-19 and Eye Floaters
While eye floaters are not a primary symptom of COVID-19, emerging research suggests a potential link between the virus and their appearance or worsening. For instance, one survey indicated that flashes or floaters were reported by 11.8% of individuals testing positive for COVID-19.
Reports of new or increased floaters after a COVID-19 infection have prompted investigations into whether the SARS-CoV-2 virus impacts the vitreous body or retinal structures. This connection is an area of ongoing research, as scientists continue to investigate the virus’s full effects on the body.
Why COVID-19 Might Lead to Floaters
The mechanisms through which COVID-19 could contribute to eye floaters are thought to involve the body’s systemic response to the infection. One hypothesized factor is widespread inflammation. The virus can trigger an exaggerated inflammatory response throughout the body, and this inflammation might extend to ocular tissues, potentially leading to changes in the vitreous humor that result in floaters. Uveitis, an inflammation within the eye, has been observed in some COVID-19 patients and can cause floaters.
Another proposed mechanism relates to vascular changes and microclots. COVID-19 can cause blood clots to form, which may travel to the eye’s blood vessels. These microclots could block nutrients from reaching the retina or cause bleeding within the vitreous, leading to floaters. Research indicates that SARS-CoV-2 can affect retinal vascularity and perfusion, potentially leading to changes in the eye’s microvascular structure. Direct viral effects on the eye’s internal structures are also being explored, as the virus can bind to ACE2 receptors present in the retina and vascular endothelium, potentially causing localized damage.
When to Consult an Eye Doctor
While many eye floaters are harmless, certain symptoms warrant immediate medical attention from an eye care specialist. A sudden increase in the number of floaters, especially if accompanied by flashes of light, is a concerning sign. These symptoms can indicate a serious condition such as a retinal tear or retinal detachment.
Other red flag symptoms include a dark curtain or shadow appearing across part of one’s vision, or any associated vision loss. Retinal detachment is an emergency situation where the retina pulls away from its supporting tissue, which can lead to permanent vision loss if not treated promptly. If any of these symptoms occur, it is important to seek an urgent eye examination to determine the cause and receive appropriate care.