Hairy eyeball caused by rare tumor

This tumor caused a 19-year-old Iranian man to sprout hair from his right eyeball.

Talk about an eye-popping discovery.

Doctors in Iran removed a rare tumor that caused hair to sprout from the right eyeball of a 19-year-old man, according to a report published Thursday in the New England Journal of Medicine.

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The tumor had been present since birth, but recently grew several black hairs and impaired the man's vision, The Daily Mail reported.

"He did not have pain, but the mass caused vision defects, mild discomfort on blinking, and the intermittent sensation of the presence of a foreign body," the journal reported.

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Doctors had to surgically remove the hairy pustule, which measured less than a quarter inch in diameter.

Called a limbal dermoid, such tumors are extremely rare, Fox News reported.

In fact, they're so rare that an optometrist is likely to see only one or two cases in their career, Dr Mark Fromer, director of Fromer Eye Centers in New York City and an ophthalmologist at Lenox Hill Hospital, told Live Science.