Treatment of port wine stains with pulsed dye laser: a retrospective study of 848 cases in Shandong Province, People's Republic of China

Background: Currently, 595 nm pulsed dye laser (PDL) therapy is offered as one of the effective treatments of port wine stains (PWSs). However, the efficacy of PDL differs in different populations. Objective: The purpose of the study was to investigate the efficacy, and related factors, of 595 nm PDL in the treatment of PWSs in Chinese patients with skin type III to IV. Methods: A total of 848 cases that were treated with PDL were enrolled and analyzed in this study. An independent dermatologist evaluated these lesions according to the before and after photographs. Results: The response rate (RR) of all the 848 PWS patients was 69.9%, within which the cure rate was 6.3%. The patients aged <= 1 year had the highest RR (93.9%), whereas those treated after age 50 reacted the worst (RR =25%). We analyzed the anatomical distribution of the lesion and found that the temporal region had the highest lesion clearance (RR =75.3%), while the extremities had the lowest clearance (RR =44.5%). Compared with the patients whose lesion size was larger than 80 cm(2), the patients with small lesion size, of 0-20 cm(2), had better clinical effect (RR =73.8% vs 53.2%). The reactions of the patients with hyperplastic lesion were worse than those with red patches (RR =36.4% vs 71.7%). As well, increasing treatment numbers could achieve higher clearance rates (P=0.005). Conclusion: The PDL had a relatively high RR but a low clearance rate in Chinese patients with PWS, although the earlier the intervention, the better was the efficacy. The response of PDL was, not only related to the anatomical area, but also, to the lesion size, type of lesion (ie, the presence of existing hyperplastic lesions), and the number of treatment, all of which are essential for the evaluation of therapeutic effect and acquisition of patients consent before treatment.