Clinical experience in skin rejuvenation treatment in Asians using a long‐pulse Nd:YAG laser

Skin rejuvenating effect of a combined triple-wavelength (755 nm, 810 nm, and 1064 nm) laser: a preliminary study

With an increasing demand for noninvasive skin rejuvenation techniques, several light-based devices have been introduced. Due to its ability to deliver thermal energy from the superficial to deeper levels of the dermis, a combined triple-wavelength laser (755 nm, 810 nm, and 1064 nm) can be used for skin rejuvenation. The objective of this study was to assess the effectiveness and safety of a combined triple-wavelength laser for skin rejuvenation. A total of 28 female patients seeking skin rejuvenation treatment were included. All patients underwent five consecutive treatment sessions at a two-week interval. Clinical improvement of aging-related cutaneous change was noted by the treating dermatologists and patients. Biopsies were performed on the faces of consenting patients before and two weeks after the final treatment. Significant clinical improvements were observed by both patients and evaluating dermatologists. Based on the patient satisfaction questionnaire, 78% of patients reported a self-assessed improvement of more than 25%. Additionally, 86% of patients showed an improvement of more than 25% on objective assessment by dermatologists. Histopathological findings revealed increased collagen and elastic bundles throughout the dermis. Except for transient pain during treatment, no serious adverse effects were reported. The findings of this study suggest that the combined triple-wavelength laser may be an effective and safe nonablative option for skin rejuvenation.

Split-face comparison of grid fractional radiofrequency vs 1064-nm Nd-YAG laser treatment of periorbital rhytides among Filipino patients

Despite multiple individual studies proving efficacy of grid fractional monopolar radiofrequency (Grid RF) and near-infrared irradiation 1064-nm long-pulsed neodymium:YAG laser (Laser Genesis), there is a lack of controlled comparative trials between these devices. This study aims to compare the efficacy and safety of Grid RF versus Laser Genesis in the treatment of periorbital rhytides. This is a randomized, single-blind, split-face, prospective study. Eight patients with moderate to severe periorbital rhytides were treated with either Grid RF or Laser Genesis on each side of the face. Photographic and live assessment with the Lemperle Wrinkle Assessment grading scale was compared after 2 months. Difference in scores between Grid RF vs Laser genesis groups after 2 months was not statistically significant (P = 0.244). Each group showed statistically significant improvement months post-procedure (P < .05). Immediate adverse effects and satisfaction scale were similar for both groups (P > .05). At 2 months follow-up, no adverse effects were seen. Grid monopolar radiofrequency (Grid RF) vs near-infrared radiation 1064 nm long-pulsed Nd-YAG laser (Laser Genesis) were equally efficacious, safe, and well-tolerated among patients in the treatment of periorbital wrinkles (P > .05).

Histological and molecular analysis of the long-pulse 1,064-nm Nd:YAG laser irradiation on the ultraviolet-damaged skin of hairless mice: In association with pulse duration change

BACKGROUND

Nonablative lasers have been widely used to improve photodamaged skin, although the mechanism underlying dermal collagen remodeling remains unclear.

OBJECTIVE

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.

MATERIAL AND METHODS

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.

RESULTS

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.

CONCLUSION

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.

Can persistent toenail fungus be successfully treated with a laser?

Onychomycosis is a common disease seen in dermatology practice. Most patients with onychomycosis opt for treatment due to the social stigma attached to the unsightly appearance, as well as the pain that can at times make walking difficult. However, in many cases, onychomycosis is resistant to oral antifungal medication, which is the first-line therapy for this disease. In recent years, we have attempted a new treatment method using a long-pulsed 1,064nm Nd :YAG laser (Cutera Inc., Brisbane, CA, USA) in refractory cases with onychomycosis. Using 1) a laser beam with a spot size of 5.0 mm and 2) sequential irradiation at low fluence, we 3) applied the laser to the infected lesions in a motion similar to showering, while maintaining a distance of several centimeters from the skin (Laser Genesis(TM)). Treatment efficacy was assessed using nail turbidity scores on a five-point scale. Improvement in onychomycosis was noted in more than 68.8% of all cases, thus demonstrating the high efficacy of this method. No major adverse reactions were observed during the treatment period. Since its mechanism of action clearly differs from that of antifungal agents, it can be considered a useful treatment option for cases with onychomycosis resistant to antifungal therapy. Future studies should examine "combined therapy" with oral / topical antifungal agents and this laser treatment, which may provide a significant improvement in the level of satisfaction among patients with onychomycosis.

Exploring the role of a nonablative laser (1320 nm cooltouch laser) in skin photorejuvenation

BACKGROUND

Nonablative laser has been used for the treatment and prevention of skin aging for many years. Although the mechanism has not been elucidated, histological evaluation showed that the dermal fibroblasts and its collagen production should be the main target for this rejuvenation. In order to determine the effects of a 1320 nm nonablative laser on the human dermal fibroblasts, the two main secretion factors, basic fibroblast growth factor (bFGF) and transforming growth factor β1(TGF-β1), in vitro were detected.

METHODS

The human dermal fibroblasts were cultured and irradiated with a 1320 nm laser at the dose of 15, 20, and 24 J/cm(2) respectively. The number of fibroblasts was counted and the levels of bFGF and TGF-β1 were detected by enzyme-linked immunosorbent assay at the time points of 0, 24, 48, and 72 h after irradiation.

RESULTS

The results showed that both the number of fibroblasts and the secretion of bFGF increased after the irradiation at the dose of 20 and 24 J/cm(2) (P<0.05) compared with that of the control cells. The bFGF secretion in the group exposed to 20 J/cm(2) was more significant than that of 24 J/cm(2), and the peak level was 24 h after irradiation. The level of TGF-β1 secretion decreased after irradiation in a dose-dependent manner (15 and 20 J/cm(2), both P<0.05; 24 J/cm(2), P<0.01), and reached a nadir at 24 h.

CONCLUSION

Our results suggested that the 1320 nm nonablative laser accelerates the vitality of fibroblasts, promotes the secretion of bFGF, and inhibits TGF-β1 secretion by fibroblasts.