Everyone experiences those annoying shadowy fibers and dots that float across the field of vision. Or perhaps you see flashes of light or starbursts when you move your head quickly or while exercising. Eye floaters and flashers are common, and tend to increase with age. Usually harmless, floaters and flashers are caused by the jelly-like liquid, called the vitreous humor, that fills the center of the eye.
Description
Eye floaters appear as cobwebs, dots, strands or threads that move across the field of vision, explains the website AboutFloaters. Floaters are inside your eye, suspended in the vitreous humor. The vitreous humor is a clear, thick gel-like liquid that fills the center of the eyeball. As the floaters move through the vitreous, they cast shadows on the retina, the thin light-sensitive membrane covering the back of the eyeball. The shadows are what you see as floaters. Floaters may be accompanied by flashers, which may appear as stars, circles or light bursts.
Cause
Floaters are causes by small clumps of protein or cells in the vitreous. Simple aging is the most common cause of floaters, notes EyeCareBasics.com. With age, the vitreous becomes thinner and pulls away from the inside of the eye. As the vitreous changes from a thick gel to a more liquid form, specks of proteins form and remain floating in the vitreous. The specks are clear but cast shadows on the retina as light enters the pupil. Floaters may also result from broken capillaries in the eye.
Flashers
Flashers are caused by the action of the vitreous, states the American Academy of Ophthalmology. The vitreous pulls away from the inside of the eye as it thins. As the vitreous slides, the gel sometimes tugs at the retina. The pressure on the retina stimulates the photoreceptors on the membrane, which are perceived as flashes of light. In some cases, the tugging of the vitreous tears a hole in the retina.
Exercise
Flashers are commonly seen during exercise or when you move your head or eyes quickly, says the Academy. Trauma to your head or eyes can also cause flashers. Sudden movements may also jostle floaters. Floaters often settle at the bottom of the eye, moving out of sight until the vitreous is agitated. Exercise may cause you to see floaters and flashers, but exercise does not affect the vitreous itself or cause retinal detachments, says ophthalmologist Ray T. Oyakawa, M.D., of Cedars-Sinai Medical Center.
Cautions
Floaters and flashers are usually harmless, although they could signal retinal detachment, warns the Academy. See an eye care professional if you notice a sudden increase in the number of floaters or flashers you see, or if the floaters hamper your vision. Also seek medical attention if an increase in floaters is accompanied by headaches or follows a blow to your head.
