Despite medicine's inestimable progress over the past century, surgery can still leave scars that look more appropriate to Frankenstein's monster than to the beneficiary of a precise, modern operation. But in the Wellman Center for Photomedicine at Massachusetts General Hospital, Irene Kochevar and Robert Redmond have developed a method that has the potential to replace the surgeon's needle and thread. Using surgical lasers and a light-activated dye, the researchers are prompting tissue to heal itself.

Laser-bonded healing is not a new idea. For years, scientists have been trying to find ways to use the heat generated by lasers to weld skin back together. But they've had a difficult time finding the right balance. Too little heat and a wound won't heal; too much and the tissue dies. Eight years ago, one of Kochevar and Redmond's colleagues was examining pathology slides of cells killed by this kind of thermal healing when it occurred to him that it might be possible to use just the light of a laser, rather than its heat.