Cold air in laser therapy: first experiences with a new cooling system.

BACKGROUND AND OBJECTIVE Analgesic cooling technologies are firmly established in dermatologic laser therapy. We present cold air as a novel method of cooling and compare it with those methods that are already in use. STUDY DESIGN/MATERIALS AND METHODS We treated 166 patients with the diagnoses hypertrichosis, port wine stains, hemangioma, essential telangiectasias, and tattoos with different laser systems (long-pulsed alexandrite laser [LPIR], pulsed dye laser, Q-switched Nd:YAG laser, Q-switched ruby laser). In a prospective study, we collected data about the analgesia of the cooling method and the thermal protection of the epidermis (reduction of the extent and duration of erythema, purpura, blisters, hyper-/hypopigmentations, edemas, crusting), compared with the cooling method with ice gel. Additionally, we measured air and skin temperatures with an infrared thermometer at different application modalities. RESULTS Three percent of the treated patients refused the cold air therapy altogether. Eleven percent found that it was as good as the other cooling methods; 86% clearly preferred the cold air therapy. Leaving out the perinasal area, the percentage rises to 97%. On average, the analgesic effect was by 37% better than through cooling with ice gel. The increased thermal protection of the epidermis made it possible to use laser energy levels that were higher by 15-30% and, at the same time, to reduce the rate of side effects (in 63% of the patients erythema persisted for a shorter period, in 70% the purpura was reduced, 83% had less crusting). CONCLUSION In dermatologic laser therapy, the use of cold air in analgesia can be considered as an effective, inexpensive, and well-accepted (by both patients and doctors) alternative to currently applied cooling methods. Nevertheless, further prospective studies are necessary to determine whether treatment results can really be improved by using higher laser energy levels.