Why is U2's Bono always wearing sunglasses? He finally revealed the answer...

Has anyone every seen U2's Bono without his glasses? Our guess would probably be no.

He has been known for wearing sunglasses throughout his career.

Bono explained during a recent appearance on British talk show The Graham Norton Show that he was diagnosed with glaucoma more than two decades ago.

He revealed: "This is a good place to explain to people that I've had glaucoma for the last 20 years."

Glaucoma is caused by a build-up of pressure in the eyeball when the fluid in the eye cannot drain properly. And this can damage the optic nerve.

It can lead to blindness, if let untreated.

Bono said that he never expected a diagnosis like glaucoma because he had perfect vision.

He said: "So I would go to do these eye tests and I would say, 'But I don't really need one because I got perfect vision and I can read the bottom line.' And they would go, 'Oh…have you ever had sort of strange visions of steam coming into the room and rings around lights?' And I went, 'Oh, yeah, and it's not from anything exotic.'"

Source: E Online, Mail Online

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