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Purpura-free treatment of lentigines using a long-pulsed 595 nm pulsed dye laser with compression handpiece: a randomized, controlled study.

BACKGROUND
Pulsed dye lasers (PDL) are one of the first, and popular, nonablative lasers for the treatment of rhytids and superficial pigmented lesions. Recent addition of a compression handpiece (CHP) allows treatments with minimal adverse effects.


OBJECTIVES
The purpose of this study was to investigate the efficacy and safety of new parameters of 595 nm PDL in the treatment of lentigines and wrinkles in the darker skin phototypes.


MATERIALS AND METHODS
Ten female subjects with photodamaged skin were enrolled in this study. One side of the face received three monthly treatments with one pass of PDL with the fluence of 6 J/cm2, 6 msec pulse duration followed by a second pass when lentigines were individually treated with CHP 6 J/cm2, 6 msec with CHP. The untreated side served as control. Digital photography was used for global evaluation while the numbers of lentigines and wrinkles were analyzed by VISIA.


RESULTS
All 10 subjects, aged 39-55 years, completed the study. The mean changes in numbers of lentigines at the twelfth week on the treated side was -6.1 (decrease), while that of the controlled side was +2.8 (increase) (P=0.075, paired t test). There was also a statistically significant difference in the degree of improvement of lentigines by global assessment (P=0.008, Wilcoxon signed rank test). No statistically significant difference in the degree of improvement of wrinkles analyzed by VISIA (P=0.490) and global assessment (P=0.157, Wilcoxon signed rank test) was observed. Hyperpigmentation was seen in two subjects.


CONCLUSION
The parameters of 595 nm PDL used in this study are effective and safe in the treatment of facial lentigines. There was no significant improvement in wrinkles in this study. A study limitation may be the relatively small sample size.