INTRODUCTION: Solar lentigines are among commonest cosmetic problems. There are many topical therapies suggested to treat these lesions including cryotherapy, chemical peeling with tri chloro acetic acid (TCA) and laser therapy with q-switched lasers as well as long pulsed lasers. Considering possible treatment side effects (PIH, scar) with cryotherapy and peeling in Iranian patients (darker skin types) it seems necessary to try to find alternative measures. The aim of the present study was to evaluate effect of long pulsed dye laser (LPDL) on lentigines via an objective method (computerized dermoscopy).
METHODS: Patients with pathologically confirmed lentigines were selected if they agreed to participate in the study,were not treated before, hadn’t history of psoriasis, vitiligo, scar formation and were not pregnant. Letigines were dermoscopied before and after treatment with PDL (V-beam, 595nm, Candela Corp. Wayland, USA) using fluence of 10 joules, without DCD (dynamic cooling device) via extra compress lens provided with laser system. The resulting figures were compared by two academic unrelated dermatologists as well as by computerized analysis. Post laser side effects were treated with topical antibiotics and mild topical steroids. Patients were followed for six months after the end of the study to determine the rate of recurrence via dermoscopy of sites of previous lesions and also delayed side effects.
RESULTS: A total of 21 patients with the same number of lesions, were included in the study. Mean age of patients was 54.2 years (±23.3) ranging from 39 to 71 years. Included patients were 18 females and three males. From 21 treated lesions, 11 were located on the hands and 10 on the face. Comparing before and after photographs taken through dermoscopy system, revealed that approximately 57% of patients had more than 75% improvement. Mean pigment analysis score (calculated by computerized dermoscope software) was respectively 8 and 2 before and after PDL therapy, showing noticeable decrease in pigment density of lesions. Side effects were mild erythema and local irritation responding to topical mild steroids. No hypo or persistent hyper pigmentation or other delayed side effects was seen after six months follow up. One patient experienced transient hyper pigmentation of treatment site after treatment. During six months follow up, no recurrences were seen.
CONCLUSION: In conclusion, PDL is a safe and effective option to treat lentigines if applied properly using compression method, especially in Iranian patients. However, further studies with larger sample size are required to confirm these results.