Losing your face isn't pretty. Whether it's the trauma of a tumor or the thrash of a car windshield that causes it, reconstructive plastic surgery can only do so much.
While a nose or ear is more easily faked because those features don't move a whole lot, eyes are a trickier matter. For example, a glass eye can be semi-convincing, but without a working eyelid anyone the patient has contact with is faced with an unblinking eye betraying its artificiality. Fortunately, doctors at Humboldt University in Berlin have engineered an ingenious peeper protector. Dr. Martin Klein and his colleagues have outfitted a 60-year-old patient's silicone facial prosthesis with the world's first bionic eyelid.
First, a latex membrane was fashioned into an eyelid from plaster casts taken of the glass eye. The elasticity of the latex keeps the lid closed until it's pulled open by a tiny thread spooled onto a micromotor rigged with a battery and control circuitry behind the glass eye. The real trick, though, is timing the blink of the artificial eyelid with its natural counterpart. The solution? Use the body's own electrical system as a switch, the same way some prosthetic arms are actuated by amputees' remaining shoulder muscles.
"[The electrical pulse] from muscles of the upper eyelid was tapped with a thin needle electrode," Klein explains. The involuntary blinks were then mimicked by the artificial eyelid.
After 300,000 test blinks, the mechanism showed no signs of wear.
"The new prosthesis gives the patient a more natural appearance so that he can live as normally as possible," says Klein, whose next goal is to add motion to the glass eye itself. After that, he says, it's just a matter of time before surgeons outfit blind patients with micro-cameras jacked directly into the visual cortex.
David Pescovitz is a contributing editor to Wired and co-founder of www.tvultra.com, your daily guide to fringe television.