London: U2 frontman Bono has revealed that the reason he always sports sunglasses is because he has glaucoma.
Bono, 54, was on 'The Graham Norton Show' alongside his fellow band members and actors Robert Downey Jr, Robert Duvall and Stephen Fry, reported Daily Mirror. Bono was asked by Norton about his sunglasses when Norton was showing photos of the group in the early stage of their career, when Bono was notably without his glasses.
Norton asked "Do you ever take them (the glasses) off?" To which Bono replied "I have glaucoma. For the last 20 years."
Bono further explained his vision is slightly impaired as he sees some objects and lights accompanied by rings and cloudiness, both of which are typical signs of Glaucoma.
Glaucoma is usually caused by the build up of pressure in the eye as the fluid (called aqueous humour) contained in the eye is unable to drain properly.
This build up of pressure can cause damage to the optic nerve and, if left untreated, can cause permanent visual impairment.
Bono explained he is receiving treatment and it is a manageable condition.