After 30 days, the laser bonding scars (bottom) are smaller than those from needle and thread

Tel Aviv University physicist Abraham Katzir and colleagues have developed a laser-based wound-closure device with a feedback loop that prevents it from overheating tissues. Their early research hunted for the temperatures at which flesh will bond to itself and heat without damage. (It’s between 60 and 70C.) Then the group designed a pen-sized tool that combines optic fibers with channels for the laser and one for an infrared sensor to measure, monitor, and control the temperature. Surgeons need only move the pen’s tip along a cut, bonding with proteins in the tissue. Compared to traditional needle-and-thread sutures, laser bonding promotes faster healing, lower risk of infection, and less scarring.

The first human trials have been successfully completed. The method has a wide range of applications, from delicate surgeries on blood vessels to procedures, such as cornea transplants, in which sutures cause discomfort and inflammation.