CNN  — 

Billy Joel’s upcoming tour dates have been canceled as the legendary performer seeks treatment for normal pressure hydrocephalus (NPH), a condition that affects the brain, according to a statement released on said Friday.

The statement, posted on his Instagram page Friday, stated that Joel’s condition “has been exacerbated by recent concert performances, leading to problems with hearing, vision, and balance.”

“Under his doctor’s instructions, Billy is undergoing specific physical therapy and has been advised to refrain from performing during this recovery period,” the statement read. “Billy is thankful for the excellent care he is receiving and is fully committed to prioritizing his health.”

The statement added that Joel “looks forward to the day when he can once again take the stage.”

CNN has reached out to Joel for further comment.

The singer was quoted in the statement, saying he was “sincerely sorry to disappoint our audience.”

Normal Pressure Hydrocephalus is a “very rare condition” that “occurs when a person has too much fluid in the brain,” according to Yale Medicine. Fewer than 3% of adults over the age of 65 are diagnosed with NPH and it affects men and women equally.

It was previously announced in March that Joel was postponing eight tour dates so that he could focus on recovering from recent surgery. A statement posted to his Instagram page at the time that he was set to “undergo physical therapy under the supervision of his doctors.”

“While I regret postponing any shows, my health must come first. I look forward to getting back on stage and sharing the joy of live music with our amazing fans,” Joel wrote, adding that he was “expected to make a full recovery” from the undisclosed medical condition.

The “Piano Man” singer on Friday announced that he was canceling 17 dates total, including the eight rescheduled shows.

Joel’s statement notified ticket holders that they will be automatically refunded the cost of their tickets.