Mary Tyler Moore suffered from significant loss of eyesight for years, her husband has revealed. Photo / Getty Images

Sitcom star Mary Tyler Moore hid the fact that she was almost blind for nearly 30 years before her death.

Her widower, Dr Robert Levine, has revealed “her significant visual loss actually started to be manifest in the late 80s”, and added that she had hidden it “very well” from her fans.

Her visual impairment was the result of a type 1 diabetes diagnosis when she was 34.

Moore, who died in 2017 aged 80, had retinal photocoagulation therapy - a procedure that burns away the peripheral retina to keep the central retina intact - in the late ‘80s.

Levine told Page Six: “So she was able to continue to read and to work but she had like, tunnel vision, where she really couldn’t see below her waist ... [things] got progressively worse.”

Moore’s eyesight continued to fail. When she was presented with a SAG award in 2012, she had to be escorted to the stage off-camera.

“They brought the lights up and she was there,” Levine recalled.

“And the reason for that was she could not walk safely across the stage at that point. It stole her ability to be autonomous and independent and she couldn’t read … her joy was robbed from her. So it was devastating.”

After his wife’s death, Levine established the Mary Tyler Moore Vision Initiative to campaign against diabetic retinal illness.

The pair met when Levine, a cardiologist, was treating Moore’s mother and she asked him if he knew of a cure for “acute loneliness”. They eventually married in 1983 and their love story has now been retold in new HBO documentary Being Mary Tyler Moore.

The doco recaps Moore’s impressive career, from playing Laura Petrie on The Dick Van Dyke Show to appearing as Mary Richards on her own sitcom in the 1970s. It also tackles her difficult personal life - she lost her younger sister Elizabeth to suicide in 1978, she witnessed her mother’s alcoholism and later struggled with alcohol herself, and lost her only child Richie when he was 24.

When Levine met Moore, he became her “safe space”, he recalled.

“I guess that kind of happens when you finally find someone you’re comfortable with and can relax, and who doesn’t judge and allows you to show a little bit more of yourself,” he told the outlet.

“And I’m grateful that I was able to do that with her and she was able to do that for me.”