Undulating like strands of kelp drifting on a minuscule ocean, "eye floaters" can be annoying. Sooner or later 70 percent or so of us will endure eye floaters or their pesky cousins, eye flashes.
Although a variety of medical conditions can cause floaters and flashes, the most common culprits are iffy connections between the back of the eye and the vitreous, the eye's Jell-O-like core.
Sometimes — especially as we age and our vitreous thins — little patches of the wobbly thing can pull free from the back of the eye. As the vitreous yanks on the touchy retina nerves, sparks fly and flashes appear. And sometimes strings of vitreous cells are torn free. These cells bobbing about in the vitreous cast shadows on the retina, which we see as floaters. The sudden appearance of bursts of flashes or large floaters can indicate serious medical conditions, such as a detaching retina, and warrant a trip to an ophthalmologist.
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