Sir Elton John says the last 15 months have been 'challenging' as he shares update on 'devastating' sight loss

The 78-year-old music icon has opened up about the impact the condition has had

Sir Elton John says the last 15 months have been 'challenging' as he shares update on 'devastating' sight loss

The 78-year-old music icon has opened up about the impact the condition has had