Dr. Frank Ryan, 50, whose other clients included Gene Simmons, Vince Neil, Adrianne Curry and Shauna Sand, was killed Monday afternoon when his Jeep went off the side of the Pacific Coast Highway and smashed into boulders, according to TMZ.
Ryan suffered major head injuries and died at the scene. Just before the accident, Ryan had been hiking near Malibu with his Border Collie, Jill, and shared a photo on Twitter.
"After 25 years of driving by, I finally hiked to the top of the giant sand dune on the pch west of malibu," he wrote. "Much harder than it looks! Whew!"
Montag, whose dramatic transformation drew condemnation as an example of the wrecthed excess of Hollywood plastic surgery, tweeted after learning of Ryan's death.
"I am devastated to hear the news of Dr. Frank Ryan's death," the reality TV star wrote. "He was the most amazing person I have ever known. He was an angel and changed my life and the lives of everyone he met. He was the most brilliant talented surgeon who will ever exist. Dr. Frank Ryan changed the world."