(Photo: University Medical Center Utrecht)
A Dutch woman had a rare bone disorder that caused her skull to grow from 1.5 centimeters thick to 5 centimeters thick. Among other problems, this disorder gave her terrible headaches and reduced her eyesight. Eventually, it would kill her. So surgeons led by Dr. Bon Verweij at the University Medical Center Utrecht replaced her skull with a plastic one produced by a 3D printer.
Dr. Verweij had worked with skull implants before, but never as large as this one. The operation was nonetheless tremendously successful. The patient has regained her sight and recovered enough to return to work. You can read more about her case at Wired.
-via Popular Science