Uncertainty in the amount of power delivered by CO2 medical lasers.

Carbon dioxide medical lasers are being used for various clinical applications with considerable success. Despite the bulk of the generating equipment, the use of light, articulated arms to deliver the power beam to either hand-held or microscope-mounted aiming heads allows accurate power placement. In addition, the beam can be focussed to a small spot size, minimizing damage to adjacent tissue provided that the output power and the precise duration of application are known, and the shielding of deeper tissue has been adequate. In an attempt to assess the reliability of the laser beam as a significant surgical tool (particularly suitable for fine cutting functions in microsurgical procedures), we tested the power output of some of the CO2 surgical lasers now available in Australia. An alarming discrepancy was found between the actual power delivered and the higher power value displayed as being delivered. As these medical lasers were tested and passed as fully functioning by their local agents, it is suggested that purchasers of CO2 lasers should be aware of these possible power inadequacies and subject their equipment to frequent power checks. Otherwise much longer applications of the laser beam will be needed to accomplish the cutting action required, with the consequent infliction of more damage to the surrounding tissues.