The 68-year-old 2000 AD veteran discussed the extent of the damage with the Daily Record.
"I've been invited to Dundee for a special screening of [Dredd 3D] and I can't wait to watch Dredd brought to life on the big screen," he said. "However, I don't know how much of the action I will see as I have glaucoma and my vision is quite limited.
"Forget 3D, I will have trouble focusing on it in 2D."
Kennedy has had three operations, which have limited the deterioration. He experiences periods when he can only see in black and white.
"It's frustrating because if I'd had the surgery way back, my whole sight could have been saved," he said. "I'm now stuck with binocular vision."
Kennedy joined 2000 AD in the late '70s, shortly after its inception. He drew Judge Dredd stories for 28 years, and also has credits with Marvel Comics, DC Comics and Dark Horse Comics.
Watch Karl Urban discussing Dredd 3D below: