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The histologic responses to varied parameters of 1,927-nm fractional thulium fiber laser treatment have not yet been sufficiently elucidated.This study sought to evaluate histologic changes immediately after 1,927-nm fractional thulium fiber laser session at various parameters.The dorsal skin of Yucatan mini-pig was treated with 1,927-nm fractional thulium fiber laser at varied parameters, with or without skin drying. The immediate histologic changes were evaluated to determine the effects of varying laser parameters on the width and the depth of treated zones.The increase in the level of pulse energy widened the area of epidermal changes in the low power level, but increased the dermal penetration depth in the high power level. As the pulse energy level increased, the increase in the power level under the given pulse energy level more evidently made dermal penetration deeper and the treatment area smaller. Skin drying did not show significant effects on epidermal changes, but evidently increased the depth of dermal denaturation under both high and low levels of pulse energy.These results may provide important information to establish treatment parameters of the 1,927-nm fractional thulium fiber laser for various skin conditions.

Nonablative lasers have been widely used to improve photodamaged skin, although the mechanism underlying dermal collagen remodeling remains unclear.To investigate the effects and the molecular mechanisms of long-pulse neodymium-doped yttrium aluminum garnet (Nd:YAG) laser irradiation on dermal collagen remodeling in association with different pulse durations.Five hairless mice were pretreated with ultraviolet B irradiation for 8 weeks. The dorsal quadrant of each mouse was then irradiated twice at 1-week intervals at a pulse duration of 1 ms, 12 ms, or 50 ms, and a constant fluence of 20 J/cm(2). The levels of dermal collagen, mRNAs of procollagens, matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinases (TIMPs), and various growth factors were analyzed after 4 weeks.Long-pulse Nd:YAG treatment increased the dermal collagen level. A substantial increase in the level of procollagens, MMPs, TIMPs, and various growth factors was also observed irrespective of pulse duration, with a trend toward maximal increase at a pulse duration of 12 ms.Long-pulse 1,064-nm Nd:YAG laser irradiation promotes wound-healing process, which is characterized by the induction of growth factor expression and subsequent increase in MMPs and TIMPs, followed by matrix remodeling as confirmed by new procollagen production.

Hyaluronic acid (HA) fillers are frequently used for the correction of facial soft-tissue defects.To compare the efficacy and safety of a novel monophasic HA filler (mono-HA), and a well-studied biphasic HA filler (bi-HA), in the treatment of moderate to severe nasolabial folds.In this randomized, evaluator-blinded, split-face comparative study, subjects were randomized for injections with mono-HA or bi-HA on the left or right side of the face. Efficacy was determined by calculating the change in the Wrinkle Severity Rating Score (WSRS) relative to baseline. Local safety was assessed on the basis of subject diary entries which recorded erythema, swelling, induration, pruritus, irritation, mass, hematoma, pain, and dryness.At week 24, the mean improvement in the WSRS from baseline was 2.18 ± 0.42 for the mono-HA side and 2.16 ± 0.41 for the bi-HA side. Both fillers were well-tolerated and adverse reactions were mild and transient in most cases.Mono-HA has a non-inferior efficacy to bi-HA in the treatment of moderate to severe nasolabial folds.

Background: The injection of botulinum toxin is now commonly used for many therapeutic and cosmetic purposes but because of its increased use more adverse events are being reported. Objective: To retrospectively evaluate and analyze the safety of botulinum toxin injections in terms of purpose and the type of toxin administered. Materials and methods: Data were collected on 1819 patients who underwent a total of 5310 treatments between 2005 and 2011 at a single tertiary medical center. Information on the dosage, treatment purpose, type of botulinum toxin, and any adverse events associated with these treatments were collected and analyzed. The generalized estimating equation (GEE) with the logistic link function was used to estimate the overall frequencies of adverse events. A multivariable GEE with the logistic link function was used to identifythe factors associated with adverseevents.Results :A mong the 5310 botulinum toxin treatments in our study cohort, 2258 of which (42.5%) were used to treat hemifacial spasm, 184 adverse events (3.73%) were recorded, 114 (2.26%) muscle-related, and 71 (1.47%) muscle-unrelated. The highest number of adverse events (8.29%) was associated with the treatment of blepharospasm and the lowest (1.07%) with masseter hyperplasia. By multivariate analysis, the odds ratio for females was 1.577 (95% confidence interval [CI] = 1.052–2.364; p = 0.027) and for the dose was 1.006 (95% CI = 1.002–1.010; p = 0.005). When compared with upper face wrinkles, the odds ratio was 2.510 (95% CI = 1.400– 4.499; p = 0.002) for blepharospasm, 0.375 (95% CI = 0.202–0.695; p = 0.002) for cervical dystonia, and 0.114 (95% CI: 0.015–0.862; p = 0.035) for masseter hyperplasia. Conclusion: When injecting botulinum toxin for cosmetic purposes, practitioners should be cautious, especially when targeting the areas around the eyes, as these treatments are prone to cause adverse events.

The most characteristic feature of melasma is the hyperpigmentation of facial area, but recent studies revealed that the melasma lesion is more erythematous than the perilesional area (1,2). In add...