RAPID COMMUNICATIONS HISTOLOGICAL CORRELATION IN LASER SKIN RESURFACING

Modern CO2 systems can be programmed to emit high power density short pulses to produce instantaneous conversion of cutaneous tissue to a ga seous state. Tissue ablation occurs so quickly that there is minimal t hermal conduction to the adjacent structures. The limits of thermal in jury can be minimized to the order of only 50 mu thick and, in spite o f the limited effects of heat conduction, coagulation in vessels can b e obtained as well, since small blood vessels are immediately sealed b y the laser. Collimated handpieces deliver a fixed beam diameter for m ore uniform vaporization at a constant energy density, as the handpiec e is steadily moved over lesions situated on uneven facial contours. T he fluence used is about 250 mJ for a 3 mm spot size and these paramet ers can be used for clean, repeatable and predictable ablation of tiss ue, taking advantage of the concept of the known thermal relaxation ti me of soft tissue.