Evaluation of different temperatures in cold air cooling with pulsed-dye laser treatment of facial telangiectasia.

摘要

BACKGROUND AND OBJECTIVES: Cold air cooling is widely used in dermatological laser therapy. We investigated the influence of cold air cooling at different skin temperatures on therapeutic outcome and side effects of pulsed dye laser treatment of facial telangiectasia. STUDY DESIGN/MATERIALS AND METHODS: From September 2002 to February 2003, 17 patients with previously untreated facial telangiectasia underwent a single treatment session with flash-lamp pulsed dye laser (3.5 J/cm(2), 585 nm, 0.45 milliseconds pulse length, 10 mm beam diameter, Cynosure V). The treatment area was divided into three sub-areas: no cooling, cold air cooling to 20 degrees C and to 17 degrees C skin temperature. The skin temperature was monitored by a prototype infrared sensor system which controlled the temperature of the cold air stream (Cryo5). In a prospective study, we collected data on purpura, pain, clearance, and patient satisfaction on numerical analog scales (NAS) from 0 (meaning no pain (2.41), and clearance (2.35) were rated medium to high. Cooling to 20 degrees C reduced purpura (1.12) and pain (1.06), whereas the clearance (2.12) was only slightly affected. Cooling to 17 degrees C reduced purpura (0.88) and pain (0.76) even more, the clearance (2.06) was lowered marginally. Most patients preferred cooling to 20 degrees C skin temperature. CONCLUSION: In dermatological laser therapy of facial telangiectasia, the use of cold air cooling can significantly reduce side effects and increase patient satisfaction while only slightly affecting clearance. Cooling to 20 degrees C skin temperature proved to be a well-balanced middle course. For the practical use of cold air cooling, we thus recommend cooling to a level which the patient can tolerate without problems and to try to increase the energy densities.