Laparoscopic surgery with a new tuned high-energy pulsed CO 2 laser.

Although CO 2 lasers have gained popularity in operative laparoscopy, it has been suggested that they do not deliver sufficiently high power density at the distal end of a laparoscope. Heating of the insufflation gas inside the laparoscope by absorption of some of the laser power causes the gas density to change and creates distortion and defocusing, resulting in lower power density at the tissue as the laser power is increased. A new laser uses the carbon-13 isotope in the laser gas mix instead of the carbon-12 isotope, which is used in both conventional lasers and CO 2 insufflation gas. The new laser was found to have no noticeable effect on tissue attributed to distortion or power loss from absorption in the insufflation gas, and it allowed the surgeon to work with minimal thermal side effects, such as the formation of charred tissue. The laser was fitted with separate controls for adjusting pulse energy and average power, allowing the surgeon to control the laser-tissue response at different operating speeds.