Explained: Why Roseanne Barr Is Losing Her Eyesight

The former sitcom star revealed she has glaucoma and macular degeneration. (Photo: Grant Lamos IV/Getty Images)

Roseanne Barr has a razor-sharp tongue that’s kept us entertained for nearly four decades, but she recently revealed that it’s her eyes — not her voice — that are her main concern right now.

“I have macular degeneration and glaucoma, “ she told The Daily Beast in an interview published Tuesday.

Barr is not alone — macular degeneration and glaucoma are the top two leading causes of irreversible blindness in the world, according to Quan Nguyen, MD, director of the Stanley M. Truhlsen Eye Institute at the University of Nebraska Medical Center.

"Think of the eye like a camera: You need all of the components of the camera in order for it to work correctly,” he explains to Yahoo Health. Both conditions affect your “camera” in different, but potentially devastating, ways. Macular degeneration typically occurs in Caucasians age 55 and older and affects the central part of the retina responsible for 90 percent of central vision. Glaucoma is caused by increased pressure on the optic nerve located on the back of the eye.

Just because you have one condition doesn’t mean you’ll get the other. Barr said that her father also suffered from eye problems, which is common with macular degeneration, according to Carlo Pelino, OD, director of Optometric Retina Service at The Eye Institute of the Pennsylvania College of Optometry.

“If a person develops macular degeneration, it’s more than likely the person has the genetic predisposition to getting it,” Pelino tells Yahoo Health. However, just because the genetics are there doesn’t mean it’s an absolute that a person will develop the disease — a lot of it has to do with inflammation caused by poor lifestyle choices. “As the patient ages, lifestyle — like a bad diet, no exercise, and obesity — kick those genetics into gear and bring on disease."

There are two different types of macular degeneration: Dry and wet. "Dry” macular degeneration makes up about 80 percent of cases and involves the degeneration of the macula in the center of the retina. The problem? It’s difficult to detect because one of the markers of it – loss of centralized vision – isn’t easy to see when your seeing with both eyes, Pelino explains.

Related: Nine-Year-Old Boy Sees His ‘Bucket List’ Before Going Blind

“Wet” macular denegation is the next step of the disease and happens when abnormal blood vessels leak blood or fluid into the macula. Once it gets to this point, it’s difficult to treat, so doctors focus on preventing the disease from advancing with a course of high-dose vitamins and antioxidants, along with lifestyle changes.

Glaucoma is also genetically influenced, but unlike macular degeneration, it can affect people of all ages and ethnic backgrounds. It’s often associated with increased pressure in the optic nerve.

“The optic nerve is the cable that connects the eye to the brain,” Nguyen tells Yahoo Health, adding that once it’s damaged, there’s no way to change it and blindness will likely occur. “At this moment, we still cannot transplant certain parts of the eye, including the optic nerve.”

Like with macular degeneration, the likelihood of treatment working depends on the stage. “Early on, medication can work to take off some of the pressure,” says Nguyen. Then there are laser therapy and surgical intervention to create different holes in the eye to relieve pressure.

As for how Barr is treating her conditions? The former sitcom star is a vocal proponent of legalizing marijuana because, in part, she says it helps alleviate the symptoms of the diseases. “It’s a good medicine for a lot of things,” she told The Daily Beast.

The medical benefits of marijuana on blinding conditions like macular degeneration and glaucoma aren’t clear, but both Pelino and Nguyen do agree regular eye exams are the key to prevention and early detection.

Glaucoma and macular degeneration “can be a silent eyesight killers,” says Nguyen. “You wouldn’t recognize how bad it is until it’s truly a problem. There are have significant advancements in treatments in the past decade and we’re able to do more to help these conditions. But we emphasize early diagnosis so you can protect yourself.”

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