ORLANDO, FLORIDA-Today's plastic surgery involves hair-raising incisions, painful recovery and scar tissue that can last forever. Now, a chemist and a doctor have found a way to remove the knife from some surgeries, a new method that uses light electrical pulses to soften the tissue so that it can be remodeled without cutting. This week at the biannual national meeting of the American Chemical Society here, they reported that the technique works on rabbit cartilage and fibrous tissue of the cornea of the eye. In people, one day it could inspire procedures to make quick repairs without pain in the nose or to correct vision.
"It's simple, quite elegant and important," says Michael Carron, head of plastic and reconstructive surgery at Wayne State University in Detroit, Mich., Who was not involved in the work. The technique has the potential to be widely applied, he says, treating everything from the damaged tracheas to the deformities of the ribs.
Brian Wong, a head and neck surgeon at the University of California, Irvine, wanted a less invasive way to remodel cartilage, a key step in many nose and ear surgeries. Originally he 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 electric current. That worked better, but I did not know how.
To discover what was happening, Wong joined Michael Hill, a chemist at Occidental College in Los Angeles, California. Hill delved into the chemistry of cartilage, which is made of spaghetti-like collagen fibers surrounded by negatively charged proteins and positively charged sodium ions. The greater the load density, the more rigid the cartilage. Hill's group discovered that the current that pbades only 2 volts through the tissue electrolyzes the water molecules, dividing them into oxygen and hydrogen ions, or protons. The positive charges on the protons cancel out the negative charges on the proteins, which makes the cartilage more malleable. "Once the fabric is flexible, you can mold it into any shape you want," says Hill.
At the meeting, Hill reported that he and his colleagues have now shown that the approach works on the cornea, the collagen-rich transparent external coating of the eye. They printed in 3D a rigid contact lens that they then modeled with electrodes, placed in the eye of a rabbit and fired briefly with the current, which softened the cornea and reformed it into the contact mold. The procedure worked so well that even small imperfections in the contact lens that the 3D printer had created were transferred to the cornea.
Hill says it is unlikely that the technique will appear in your doctor's office soon. "It's still very early," he says. But in the future, he thinks, reshaping the cornea could replace the procedures now used to correct vision, such as laser eye surgery. Laser surgery does not work for some people and is not reversible; On the other hand, the remodeling of the cornea could be repeated if a patient's vision changes. Carron says he expects the procedure to be used even more widely, because collagen-rich tissues are found throughout the body. "I think there are many applications," he says.