Updated

Hollywood plastic surgeon Dr. Frank Ryan, best known for performing 10 surgeries on Heidi Montag in one day, died in a car crash Monday in Southern California.

After hiking in Ventura County Monday afternoon, Ryan’s jeep drove off the side of the Pacific Coast Highway. Emergency responders attempted to remove him from vehicle, but were unsuccessful. He was pronounced dead at the scene.

Minutes before his death, Ryan Tweeted: "After 25 years of driving by, I finally hiked to the top of the giant sand dune on the pch west of Malibu. Much harder than it looks! Whew! ... Border collie jill surveying the view from atop the sand dune."

His dog Jill was seriously injured, with emergency responders finding her in the ocean after the crash. She was taken to a local veterinarian for treatment, where she was treated for eye and paw injuries, then released a member of  Dr. Ryan's ranch staff, TMZ reported.

Ryan, 50, was a staple in Hollywood, working on countless celebrities including Janice Dickinson, Adrianne Curry, Shauna Sand and Gene Simmons.

But it was his work with MTV reality star Montag that earned him notoriety; he completely (and publicly) transformed the troubled celebrity's looks. Performing 10 procedures in one day, Ryan gave Montag a mini brow lift, Botox, a nose job, a "back scoop," liposuction and an ear pinning, among other alterations.

SLIDESHOW: Heidi Montag's Plastic Surgery Transformation

But Montag praised him in the hours after his death, calling him “the most brilliant talented surgeon who will ever exist.”

Taking to her Twitter page, Montag wrote, "My thoughts and prayers go out to his mother, family, friends, and anyone who was ever blessed enough to meet him. He is in a better place. I am devastated to hear the news of Dr. Frank Ryan's death. 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."

Other clients mourned his death as well, also expressing their remorse via Twitter.

"Oh my! Friend and plastic surgeon Dr Frank Ryan died yesterday in a terrible car crash. I was supposed to see him Thursday morning," model Caitlyn O’Connor Tweeted.

Public relations expert Lizzie Grubman Tweeted, “Dr. Frank Ryan RIP...you will truly be missed.”

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