The patient, a woman from Los Angeles in her late 60s, visited the doctor with an odd complaint: Every time she opened her right eye, she heard a clicking sound.
Cosmetic surgeon Allan Wu thought she might have been imagining the strange sound, but he noticed she also had considerable swelling around the drooping eyelid, according to Scientific American. After several hours of surgery, Wu was surprised to find several small pieces of bone around the woman's right eye.
The bone fragments and swelling were the result of a botched facelift the woman had received three months earlier from a different doctor: He injected stem cells derived from the woman's abdominal fat directly into the area around her eyes.
Apparently, her first doctor also injected a calcium-based compound as a filler to smooth out some wrinkles. The reaction between the stem cells and the calcium caused bone tissue to start growing beneath her skin.
And the mysterious clicking sound? That was caused by the tiny pieces of bone near the woman's eye grinding against one another each time she opened or blinked her eyes.
Cosmetic procedures involving stem cells tend to be expensive — the patient paid more than $20,000 for her botched operation — but the procedures are largely unregulated by the FDA and have not been subject to rigorous testing. As a result, a number of unapproved stem cell-based therapies, creams, pills, oils and surgical procedures are flooding the market — and putting patients' health (and bank accounts) at risk, according to Scientific American.
Stem cells have the ability to differentiate into special types of cells like skin or bone, and have been touted as ushering in a brave new world of medicine, including plastic surgery. But because stem cell treatments are so new, and regulations are so lax, the long-term effects of stem cell procedures are unknown.
"Many of us are super-excited about stem cells, but at same time we have to be really careful," Paul Knoepfler, a cell biologist at the University of California, Davis, told Scientific American.
"These aren't your typical drugs. You can stop taking a pill and the chemicals go away," Knoepfler said. "But if you get stem cells, most likely you will have some of those cells or their effects for the rest of your life. And we simply don't know everything they are going to do."
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