Story highlights Barr has macular degeneration and glaucoma, eye diseases that get progressively worse and can steal vision

The risk for both diseases goes up for everyone after age 60

Sun exposure can up the risk for glaucoma and macular degeneration

(CNN) Roseanne Barr revealed earlier this week that she is going blind. In an interview with The Daily Beast, the 62-year-old comic talked about her struggle with macular degeneration and glaucoma — two eye diseases that get progressively worse over time and can steal vision.

Barr's doctors haven't provided a timeline, but her symptoms are worsening: "My vision is closing in now," she said. "I just try and enjoy vision as much as possible. Y'know, living it up."

Macular degeneration is a breakdown of the part of the retina that allows us to see fine details in the center of vision; while glaucoma damages the nerve that connects the retina to the brain, and is often caused by fluid build-up and pressure in the eyes. (Barr said in the interview that she helps relieve the pressure by using marijuana, which is known to temporarily lower pressure inside the eye.)

"It's somewhat unusual that Roseanne Bar has both, but not unheard of," explains ophthalmologist Steven A. Shanbom, MD, of Shanbom Eye Specialists in Berkley, Mich. Though there are some controllable risk factors, certain people are genetically predisposed to these diseases, so Barr may simply be prone to both. "Certainly it's sad. The combination of the two is terrible. Macular degeneration takes away her central vision, and glaucoma is taking away her peripheral vision," Dr. Shanbom adds. (He is not treating Roseanne Barr, and does not know the specifics of her case.)

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