Plastic surgery today involves grisly incisions, painful recovery, and scar tissue that can last forever. Now, a chemist and a physician have come up with a way to take the knife out of some surgeries—a new method that uses mild electric pulses to soften tissue so it can be reshaped without cutting.
This week at the semiannual national meeting of the American Chemical Society here, they reported that the technique works on rabbit cartilage as well as the fibrous tissue in the cornea of the eye. In people, it might one day inspire procedures for fast, pain-free nose jobs or corrective vision repair.
“It’s simple, rather elegant, and important,” says Michael Carron, chief of plastic and reconstructive surgery at Wayne State University in Detroit, Michigan, who was not involved with the work. The technique has the potential to be applied widely, he says, treating everything from damaged windpipes to rib deformities.
Brian Wong, a head and neck surgeon at the University of California, Irvine, wanted a less invasive way of reshaping cartilage, a key step in many ear and nose surgeries. He originally tried to use an infrared laser to heat the cartilage and make it more flexible. That approach worked, but the heat also damaged—and killed—some of the tissues. Then he tried to apply an electrical current. That worked better—but he didn’t know how.
To find out what was going on, Wong teamed up with Michael Hill, a chemist at Occidental College in Los Angeles, California. Hill delved into the chemistry of cartilage, which is made of spaghettilike collagen fibers surrounded by negatively charged proteins and positively charged sodium ions. The greater the density of charges, the stiffer the cartilage. Hill’s group found that passing current at as little as 2 volts through the tissue electrolyzes water molecules, splitting them into oxygen and hydrogen ions, or protons. The positive charges on the protons cancel out the negative charges on the proteins, making the cartilage more malleable. “Once the tissue is floppy, you can mold it into whatever shape you want,” Hill says.
At the meeting, Hill reported that he and his colleagues have now shown the approach works in the cornea, the collagen-rich transparent outer covering of the eye. They 3D printed a rigid contact lens that they then patterned with electrodes, placed on a rabbit’s eye, and briefly shot through with current, which softened the cornea and reshaped it to the mold of the contact. The procedure worked so well that it even transferred to the cornea tiny imperfections in the contact lens that had been created by the 3D printer.
Hill says the technique is unlikely to pop up in your doctor’s office any time soon. “It’s still really early,” he says. But in the future, he thinks, remolding the cornea could substitute for procedures now used to correct vision, such as laser eye surgery. Laser surgery doesn’t work for some people, and isn’t reversible; in contrast, corneal remolding could be repeated if a patient’s vision changes. Carron says he’s hopeful the procedure will be used even more widely, because collagen-rich tissues are found throughout the body. “I think there are a lot of applications,” he says.
Source:
Sciencemag.com
