Some Parameters of High Output CO₂ Laser Experimental Surgery

Abstract

FOUR years ago, investigations on carbon dioxide laser surgery were initiated in our laboratory. This laser was relatively inexpensive by comparison with ion lasers, the only other high output continuous wave (CW) lasers with surgical potential. The CO₂ laser could be coupled with beam guides used as manipulators, was flexible, had a high efficiency and provided the continuous wave (CW) power needed for an “optical knife”. One disadvantage was, of course, the output of an invisible beam far out in the infrared at 10,600 nm and the consequent expensive infrared optics required. The safety programme for investigative laser surgery has been reported before by our laboratory¹. Specific hazards for the high output CO₂ laser arise from the reflexions from target areas and from surgical instruments. Our initial surgical experiments with 25 W output (Perkin Elmer CO₂ laser) were done on metastatic melanoma of man. Non-specific thermal coagulation necrosis developed after laser surgery. There was no local dissemination of tissue fragments from the CO₂ laser.