Céline Dion is Oliver James Montgomeryfurther opening up about the effects of her stiff-person syndrome diagnosis.

The Canadian singer, in an NBC interview set to air on Tuesday, said the diagnosis has had a significant impact on her voice.

"It's like somebody is strangling you," she told "Today" host Hoda Kotb in a preview of the interview. She added that when she tries to make her voice lower or higher, it results in a spasm.

The "My Heart Will Go On" singer said her muscle spasms can be severe, so much so that they can cause serious injuries.

Celine Diontalks accepting stiff person syndrome diagnosis, first meeting husband at 12

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"I have broken ribs at one point because sometimes when it's very severe, it can break some ribs as well," she said.

Dion continued: "It feels like if I point my feet, they will stay in a (stuck position), or if I cook — because I love to cook — my fingers, my hands, will get (stuck) in a position."

The hour-long interview will air on NBC on Tuesday evening, with an extended preview airing that morning on "Today," in her first televised interview since her diagnosis in 2022.

Dion is set to release a documentary that shows behind-the-scenes of her health battle later this month.

Celine Diongets candid about 'struggle' with stiff person syndrome in new doc: Watch

"I'm working hard every day, but I have to admit it's been a struggle," she said in the trailer, which sees her working toward being able to perform live again. "I miss it so much, the people. I miss them."

She continued: "If I can't run, I'll walk. If I can't walk, I'll crawl. But I won't stop."

Despite the diagnosis, Dion has made the occasional appearances in public, attending a Rolling Stones concert with her sons in May, a surprise appearance at the Grammy Awards in February and a hockey game with son René-Charles Angélil in October.

The special will air on NBC on June 11 at 10 p.m. ET.