Surgeons can cut tissues without using knives. They use a laser beam which delivers intense heat to the tissue. The beam cuts effortlessly and with total cleanliness. It also seals blood vessels so that the cut does not bleed.
Eye surgery can also be carried out by laser-without cutting open the eye! The retina at the back of the eye can become detached, which causes blindness. Firing a laser beam into the eye can weld the retina back into place and thus restore sight.