Laser surgery is surgery carried out using a laser beam. The
high energy in an extremely narrow laser beam can burn through body tissues
to make a fine "cut". The heat also seals blood vessels, so there is much
less bleeding than when a knife is used. A less powerful laser beam can
removed colored marks, such as tattoos, from the skin. Heat destroys the
pigment because it absorbs much energy from the beam, whereas the surrounding
skin is virtually unaffected, Surgeons also use lasers to treat some forms
of skin cancer and eye problems.