COMPARATIVE STUDY BETWEEN THE PDL AND THE EXCIMER LASERS IN TREATMENT OF PSORIASISAshraf Badawi, MD, PhD, Hisham Shokeir, MD, Mona Soliman, MD, Klaus Fritz, MD, Dermatology Unit, Laser Institute, Cairo University, Egypt, Landau, Germany

Ashraf Badawi, ashrafbadawi@hotmail.com No potential conflict of interest relationships with regard to my presentation exist.

The xenon chloride (XeCl) excimer laser is able to deliver high-energy monochromatic UVB at 308nm, and is effective in the treatment of plaque psoriasis. The pulsed dye laser (PDL) is widely used for treating vascular ectatic disorders such as port wine stains (PWS). The hypothesis that selective laser ablation of dermal papillary vasculature may lead to resolution of plaque psoriasis is supported by immunohistochemical studies, confirming changes in the superficial capillary bed in psoriatic lesions, with reductions in endothelial surface area and proliferation, accompanied by reduction in T-lymphocyte infiltrate. Studies of PDL in psoriasis report response rates between 57% and 82% with complete clearance in a proportion of patients. Remission after PDL may extend to 15 months. The aim of this study was to provide a comprehensive and practical clinical comparative study between the Excimer and the Pulsed Dye Lasers in treatment of Psoriasis.

Background and Objectives Study Design and Methods Results and Conclusions

Before PDL 4 WEEKS AFTER 1 PDL TTT

60 patients with mild to moderatemild to moderate plaque type psoriasis affecting less than 20% of the body surface were included in the study after obtaining ethical approval and informed consent. Topical antipsoriasis agents (excluding emollients) were prohibited on studied plaques 2 weeks prior to first laser treatment, and for the duration of treatment and follow-up period. Patients were divided into two equal groups. The first group was treated using the Excimer laser (308nm, PhotoMedex Inc, Carlsbad, CA, U.S.A.) The other half of the patients (2nd group) were treated using the PDL (585nm, V Star, Cynosure, Westford, MA, U.S.A.) with a pulse duration of 0.5 msec. A plaque was left untreated in each patient of both the 2 study groups to serve as a control. The two groups were compared regarding the number of sessions needed, and the percentage of patients remained in remission at the end of the study period.

The clearance rate after the Excimer laser treatment reported in our study was 37% and with the PDL it was 33%. Hyperpigmentation was the most common complication. It was seen in 45% of Excimer-treated plaques and 20% of PDL-treated plaques. Although this was rather more persistent, it had generally resolved in patients followed up to 1 year. Although there was discomfort associated with PDL, all patients tolerated this without topical anaesthetic. Purpura was a complication which occurred in all the patients treated with PDL but it was usually well tolerated in most of the patients. In conclusion, Although we observed a similar remission rate and duration in our 2 study groups, many patients favoured the PDL treatment as it is once a month treatment compared with biweekly sessions of the Excimer laser. The PDL should be considered for treatment of localized plaque psoriasis, even in cases resistant to conventional or Excimer treatment.

Hyperpigmentation after Excimer laser test dose with different fluences.

Hyperpigmentation after 5 sessions of PDL treatment “Fluence=7.5J/cm2; Spot size=7mm; Pulse duration =0.5msec”