'The fluids had crystallised and had been eating away at my ear': AC/DC singer Brian Johnson reveals a rainstorm triggered sudden hearing loss which led to him being replaced by Guns N' Roses star Axl Rose

Former AC/DC singer Brian Johnson has revealed his sudden hearing loss which forced him to quit touring with the rock band was caused by 'fluid crystals' in his ear.

The English rocker, 68, told US radio station Sirius XM that 'fluids went up into (his) sinuses' after performing an outdoor concert in Canada during a rainstorm.

He was later diagnosed by an ENT specialist in the band's native Australia, who discovered the fluids had 'crystallised' and were 'eating away' at Brian's ear, leaving him partially deaf.

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Partially deaf: Brian Johnson (L), the singer of Australian rockers AC/DC, has revealed how 'fluid crystals' in his 'good' right ear accelerated the hearing loss which forced him to be replaced by Guns N' Roses singer Axl Rose for the band's Rock or Bust world tour last month. Pictured performing with lead guitarist Angus Young (C) and bass player Cliff Williams (R) in Texas back in February

After jetting Down Under following the band's North American tour dates, Brian explained he was concerned that his right ear wouldn't pop.

'I was getting worried because my right ear is my good ear,' he said, adding that his left ear is already 'just about totally deaf' from a New York motor racing event eight years years ago.

'When we got (to Australia), that’s when Dr. Chang found out that the fluids had crystallised and had been eating away at my ear,' he began.

'So my good ear, I lost I don’t know what percentage - but it was enough to make things very difficult. So they worked on me,' concluded Brian.

Out with the old, in with the new: Brian (L) will be replaced for the US and European dates of AC/DC's Rock or Bust tour with Guns N' Roses singer Axl Rose (R)

With the support of AC/DC lead guitarist Angus Young and bass player Cliff Williams he got through the treatment - but the doctor told him the hearing loss was permanent.

Brian also debunked widely-reported rumours that he was 'fired' by Angus, 61, who is currently the band's only remaining original member.

'The boys saw the charts. I’d been getting checked regularly,' he said. 'And they saw there was a massive dip and if I’d have kept on going, there was a possibility I would never hear again.

'Angus and Cliff just said, "Johnno, you’ve got to think of your health,"' he continued.

'And everybody else said, "Brian, your health comes first. You’ve done a whole year on the road. You’ve done everything. We want to finish."

'And that’s what they did. It’s simple. What people don’t understand is it is what it is,' he said.

Kicked out? Brian also debunked rumours that he was 'fired' by Angus (R), who is currently the band's only remaining original member, in favour of Axl (L), saying they pleaded to him: 'You've got to think of your health'

Despite being removed from the AC/DC's sell-out Rock or Bust tour and controversially replaced by Guns N' Rose frontman Axl Rose, Brian remained optimistic.

He added: 'I had so many good times with the boys. And I’ve had such a lucky and great life. And I’m just thankful really that I came out of it in one piece. Now I guess I could rest me socks off.' 

Lats month Brian told ABC he was 'personally crushed' to retire from live performances after he was told he risked becoming deaf if he continued.

'(It was) the darkest day of my professional life,' he said of learning he could not join AC/DC for the European and US dates of their blockbuster world tour. 

'I am personally crushed by this development more than anyone could ever imagine,' the Highway To Hell star continued.

'Being part of AC/DC, making records and performing for the millions of devoted fans this past 36 years has been my life's work.'

Brian, who joined the band in 1980 following the death of original singer Bon Scott, said he had 'no choice' for now but to step down from singing duties.

Rumours had been circulating for weeks that Axl, 54, would be joining AC/DC as touring singer amid concerns Brian risked total deafness if he played more stadium gigs.

In March, Axl was spotted leaving the band's rehearsal space in Atlanta, Georgia - as local news outlets claimed he was also seen in the city when the band were auditioning potential singers.

He was confirmed as touring singer on AC/DC's official website on April 16, as the band thanked Brian 'for his contributions and dedication to the band throughout the years'.

The statement continued: 'We wish him all the best with his hearing issues and future ventures.

Long serving singer: English-born Brian - pictured here performing alongside guitarist Angus Young (right) with AC/DC - joined the Australian rock band in 1980 following the death of original frontman Bon Scott

'As much as we want this tour to end as it started, we understand, respect and support Brian's decision to stop touring and save his hearing. 

'We are dedicated to fulfilling the remainder of our touring commitments to everyone that has supported us over the years, and are fortunate that Axl Rose has kindly offered his support to help us fulfill this commitment'

Meanwhile, fans got a sneak preview of an Axl-fronted AC/DC at the Coachella festival before he joined AC/DC for a string of European dates.

The Aussie rockers' guitarist Angus made a surprise guest appearance during a Guns N' Roses' set in California last month.

Axl belted out AC/DC staples Whole Lotta Rosie and Riff Raff, as he was joined by Slash and Duff McKagan from his band's 'classic era' line-up.

Guest appearance: Fans got a sneak preview of an Axl-fronted AC/DC at the Coachella festival last month before he joined AC/DC full-time for a string of European dates