CO2 laser resection by freehand or microscopic technique versus laser vaporization were compared in a series of 136 consecutive surgical operations. Forty-nine lesions of the vulva, 61 of the oral cavity, and 19 of the penis were classified as dysplastic, in situ, or initially invasive lesions, ranging from 0.9 to 4.5 cm of maximum extension in width and from 0.4 to 4 mm in thickness (exophytic lesions). Twenty-two lesions were vaporized, whereas 114 were resected. An average of 12% discordance was found between pre-and postoperative histologic diagnosis among the resected group, thus indicating that the laser vaporization procedure is unsuitable for those lesions because it does not offer the entire surgical specimen. More constant depth of tissue removal, reduction of operating time, and safer use were also recognized as further advantages of the excisional technique. Resection under microscopic magnification (6 to 40 x ) with the aid of the micromanipulation of the beam was used in 91 of the 114 resected lesions. This led to the optimal intraoperative resolution of the lesion borders, minimized the tissue burning effects because of the direction of the incision orthogonal to the tissue surface, and provided an 81 O/ o satisfactory histologic report of radicality, whereas the freehand-resected group reached only 40%.
In conclusion, the maximum obtainable surgical precision can be achieved for the studied lesions with proper spot, focal length, and power density of the laser beam delivered through microscopic instrumentation.