By Jonathon Dornbush
October 17, 2014 at 07:16 PM EDT

Bono is rarely, if ever, seen without his trademark sunglasses, but the U2 frontman hasn’t worn them to make a fashion statement or define his look—he has been treating his glaucoma.

Speaking on The Graham Norton Show on BBC1, Bono told the show’s host that for the last two decades he has worn dark-tinted glasses because he suffers from glaucoma. which can make eyes overly sensitive to light.

Bono went on to explain that he has been receiving treatment and will be fine. “You’re not going to get this out of your head now and you will be saying, ‘Ah, poor old blind Bono,’” he joked.

Glaucoma can lead to blindness if not treated properly, though thanks to Bono’s 20-year treatment method, that may not be an immediate concern for the singer.

The episode will air tonight on BBC1. A representative for The Graham Norton Show did not immediately respond to a request for comment.

Bono and the rest of U2 appeared to promote Songs of Innocence, and the band remains quite aware of the album’s controversy. Many iTunes users were angered by the inability to delete the album, which appeared in every iTunes user’s library last month. Bono took the publicity hit in stride, however, saying on the show that “all those people who were uninterested in U2 are now mad at U2. As far as we are concerned, it’s an improvement.”

This isn’t the first time Bono has apologized for the album’s marketing, but the continued press tour shows the band is fully behind their latest production. For more thoughts on Songs of Innocence, find out what two EW critics had to say about the album.