layer is in part exposed and is readily healed with fresh tissue either of the commercially available ultransonic surgical tools is effective i e 23 000 hertz and 37 000 hertz power output of 20 watts is effective higher power output of 35 to 50 watts appears to result in more rapid healing of the treated skin after the skin 22 has healed the freshly formed tissue as shown in fig3 tends to be relatively smooth and flat the resulting skin as shown in fig3 has fewer wrinkles and skin surface irregularities are less apparent lidocaine is a preferred local anaesthesic which presents few side reactions and few lingering effects yet is effective in reducing pain lidocaine customarily is provided with epinephrine solutions which have a low ph effective solutions of lidocaine contain about 1 ml lidocaine in 10 000 ml aqueous saline solution vaso constrictors function to contract blood vessels and retard the free release of blood in the affected region epinephrine is a preferred vaso constrictor the epinephrine can be combined with the lidocaine solution in a single injection dose the solution of epinephrine or other vaso constrictor preferably is about 1 200 000 epinephrine aqueous saline solution a spreading factor functions to cause subcutaneous fluids.