When most of us see floaters before our eyes -- those strange amoeba-like dark and light shapes that swim around in our field of vision -- we're seeing tiny flecks of a protein called collagen.
They float around the gelatinous part of our eye called vitreous humor and, as we age, both the gel and the collagen shrinks, causing us to see shreds of the protein dancing in our vision.
When a 25-year-old man from eastern India saw floaters, however, the cause turned out not to be benign collagen but a worm known as Loa loa, or the African eye worm.
"Posterior segment examination showed a grade one vitreous haze with a fairly long live worm moving around in a haphazard and relentless manner throughout the vitreous cavity," said the doctors who removed the worm. They reported their work in a paper published online in the journal BMJ Case Reports on January 8.
I don't know about you, but "haphazard," "worm," and "relentless" are certainly words I never hope to hear in relation to my eye.
While the worm has occasionally been found in the back chamber of an eye before, the doctors who worked on this case said they believe it's the first time the creature has been found in the vitreous cavity of the eye.
If you're now wondering if your floaters are actually worms, don't worry. You're probably fine.
The infected man had symptoms beyond floaters, including pain, redness and decreased vision. Before the worm was removed, the eye it called home had 20/160 vision. Two weeks after extraction, the vision returned to 20/40. The man also worked as a fruit vendor, which may have made him more susceptible to the worm because it gets introduced through the bite of the deer fly, also known as a mango fly. The fly is normally found in West and Central Africa, but has also been spotted in other parts of the world, including India.
But how did the worm wind up in the eye?
"The worm in this case, identified as an adult male L. loa, might have, in its larval stage, migrated to the vitreous cavity either from the blood through ciliary vessels or by burrowing through the coats of the eyeball and grown there," the researchers wrote. The coats of the eyeball are a reference to the three layers that protect the eyeball. Nice, huh?
Bet you never look at your floaters the same way again.
(Via Live Science)