Dion, according to the statement, has patulous eustachian tube, a condition in her middle ear that causes troubles with hearing. That condition “makes it extremely difficult to sing,” her team noted. And though she had been treating it for more than a year with ear drops, that treatment stopped working, making the surgery necessary.

According to the Dallas Ear Institute, the eustachian tube connects the middle ear cavity to the throat. But people with Dion’s condition have an issue where their eustachian tube stays open and doesn’t close when it should. That causes symptoms like muffled hearing, hearing your own voice and feeling your breathing in your ear, and an urge to “clear” your ear all the time.

Dion announced the news on her Facebook page. “My luck hasn’t been very good lately... I’ve been so looking forward to doing my shows again and this happens…. I just can’t believe it!” she said in the statement. “I apologize to everyone who planned to travel to Las Vegas to see my show. I know how disappointing this is, and I’m so sorry."

She’ll be canceling her performances from March 27 through April 18, and return to the Las Vegas stage on May 22. Anyone who has purchased tickets will get refunds.