United Kingdom, March 13 -- Billy Joel is "doing great" amid his battle with a brain disorder, his daughter Alexa Ray Joel has revealed.

The Piano Man artist, 76, was forced to cancel his tour dates last year after being diagnosed with Normal Pressure Hydrocephalus - a neurological condition that impacts balance, vision and hearing - but Alexa Ray is encouraged by her father's efforts to improve his health.

Alexa Ray told The Hollywood Reporter: "He's doing physical therapy regularly and he's doing great. He's lost weight as he's on a diet.

"I'm so proud of him. He's such a trooper, so resilient and so committed to being healthy and proactive. He's a fighter. He's always been a fighter and talks in his documentary (Billy Joel: And So I...