The front man for Irish rock band U2, Paul David Hewson, best known as Bono, is identified by his signature trademark: his tinted sunglasses. The U2 singer wants the world to know he’s not an aloof rock star who wears shades indoors just because — he wears them to protect his eyes from glaucoma. The 54-year-old revealed on The Graham Norton on BBC One, he’s had glaucoma for 20 years and now is the time to tell his fans about the eye disease.

Bono revealed the mystery behind his shades when host Graham Norton started teasing the band about their accessories. “You didn’t wear sunglasses, and then when you found them, you were like ‘I love sunglasses,’” Norton said as the crowd laughed. “Do you ever take them off?"

"This is a good place to explain to people," Bono said. "I have had glaucoma for the last 20 years.” However, the U2 front man emphasized, "I have good treatments, and I am going to be fine."

Sunglasses are commonly used by glaucoma patients as an easy solution to dealing with light and glare while outdoors. The debilitating eye disease can make eyes highly sensitive to the sun’s ultraviolet (UV) rays, making it critical for patients to seek protection from the sun. According to the Glaucoma Research Foundation, long-term exposure to UV rays can damage the eye’s surface as well as its internal structures, and can sometimes even contribute to cataracts, the clouding of the lens, and macular degeneration, the breakdown of the macula.

Although glaucoma can result in vision loss and blindness due to damage of the eye’s optic nerve, with early detection and treatment, like Bono, patients can protect their eyes against serious vision loss. Without treatment, people with glaucoma will slowly lose their peripheral (side) vision and miss objects to the side or out of the corner of their eye. Straight-ahead (central) vision can decrease until no vision remains if still left untreated.

“Now that you have this information, you’re never going to be able get it out of your head,” Bono said, after explaining the ailment. In good humor, the U2 front man foresaw and mimicked everyone’s reaction as “Ah, poor old blind Bono.” The musician made these statements a few days after he admitted in a Facebook Q&A the band’s plan to drop its new album onto Apple users' iTunes accounts was a bit shortsighted.

Other pop culture idols, like Whoopi Goldberg, have also come out talking about the eye disease and how it has impacted their careers. In her debut column for the Denver Post's The Cannabist, The View co-host admits to using marijuana to curb headaches she suffers from having glaucoma.

"These glaucoma-induced headaches come on like freight trains — like, BOOM, my head starts hurting, my eyes start bugging, my whole body starts to tense up. But then I find [Sippy, the vape pen], and it relaxes everything and calms everything. It helps my head stop hurting, and with glaucoma your eyes ache, and she takes the ache out. It’s wonderful,” Goldberg wrote.

She prefers vape pens after smoking a joint hurt her lungs. Goldberg prefers tetrahydrocannabinol (THC) oil cartridges with her favorite oil Platinum OG. She emphasizes she’s not looking for a high but for relief.

Perhaps Bono was trying to tell his fans something with his song “City of Blinding Lights,” in 2004 before Goldberg revealed her diagnosis in April of this year.