Bono Reveals He Has Glaucoma

Joe Pugliese

So that's why he's always wearing sunglasses indoors

Bono's omnipresent sunglasses aren't just part of his rock-star image. He wears them for medical reasons.

Specifically, the U2 frontman told BBC One's Graham Norton that for the past 20 years he's had glaucoma, a condition that can make eyes more sensitive to light.

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Bono revealed his condition when asked by Norton if he ever removes his shades, adding, "I have good treatments, and I am going to be fine," according to various media outlets, including The Guardian, The Telegraph and the Associated Press.

He then indicated that those who may have mocked his shades might feel bad now that they've learned the truth.

"You're not going to get this out of your head now, and you will be saying, 'Ah, poor old blind Bono,' " he said.

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Glaucoma is caused by a buildup of pressure that can damage the optic nerve and lead to vision loss and blindness if not treated. Early diagnosis and treatment can prevent further deterioration of someone's sight.

U2 appeared on Friday's The Graham Norton Show — along with Robert Downey Jr., Robert Duvall and Stephen Fry — as part of the group's ongoing promotion of their new album, Songs of Innocence, the physical version of which was released this week after being given away for free to iTunes customers.

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Regarding iTunes users upset that the album automatically appeared, Bono added that he's happy those who may have been indifferent toward the band are now expressing a stronger emotion.

"As far as we are concerned, it's an improvement," he said.

Watch Bono discuss his need for sunglasses and swap shades with Robert Downey Jr. in a clip from The Graham Norton Show below.