Q-switched double frequency Nd:YAG 532-nm nanosecond laser vs. double frequency Nd:YAG 532-nm picosecond laser for the treatment of solar lentigines in Asians

Solar lentigines are common pigmentary lesions. Q-switched lasers are effective treatment options but postinflammatory hyperpigmentation (PIH) is common in darker skin. The objective of the study is to compare the efficacy and safety in solar lentigines of Asian skin treated by Q-switched potassium titanyl phosphate (KTP) 532-nm nanosecond laser vs. KTP 532-nm picosecond laser for the treatment of solar lentigines in Asians. Thirty patients with at least 2 solar lentigines on the upper extremities were enrolled. A total of 30 paired lentiginous lesions were randomly treated with a single treatment of either Q-switched KTP 532-nm nanosecond laser vs. KTP 532-nm picosecond laser. In terms of efficacy, mean luminance score was evaluated at baseline, at 6th, and 12th week. Degree of pigment clearance was assessed by a blinded physician and the patients. Satisfaction score was rated by patients using visual analogue scale. Adverse events were also recorded. Twenty-eight patients completed the study. Both lasers showed significant improvement in mean luminance score from baseline (p?<?0.05). Likewise, there was no significant difference in pigment clearance between two lasers either assessed by physician or patients. However, patients’ satisfaction score was significantly higher with the picosecond laser (p?=?0.014). Adverse events and pain were not different between groups. Q-switched KTP 532-nm nanosecond laser and KTP 532-nm picosecond laser are safe and effective for treating solar lentigines in Asians. Based on cost-effectiveness, Q-switched KTP 532-nm nanosecond laser remains the main treatment while KTP 532-nm picosecond laser can be considered as a treatment option.     

1064-nm Q-switched fractional Nd:YAG laser is safe and effective for the treatment of post-surgical facial scars

Lasers in Medical Science - Post-surgical facial scars are often associated with unaesthetic outcome. Treatment of these scars using various lasers could be beneficial; however, the use of the...     

Prospective study of Q-switched Nd:YAG laser treatment of hyperpigmented split-thickness skin grafts

Lasers in Medical Science - Hyperpigmentation of split-thickness skin grafts (STSGs) is commonly found among Asians, and it is also challenging to treat. Although the 1064-nm Q-switched Nd:YAG...     

Split-face comparison of the picosecond 1064-nm Nd:YAG laser using a microlens array and the quasi-long-pulsed 1064-nm Nd:YAG laser for treatment of photoaging facial wrinkles and pores in Asians

Lasers in Medical Science - Skin photoaging manifests deeper wrinkles and larger pore size. Various lasers have been tried for rejuvenation of photoaging skin, and the quasi-long-pulsed 1064-nm...     

Potential role of S100A8 in skin rejuvenation with the 1064-nm Q-switched Nd:YAG laser

The 1064-nm Q-switched Nd:YAG laser is demonstrated to be effective for non-ablative skin rejuvenation, but the molecular mechanism by which dermis responses to laser-induced damage and initiates skin remodeling is still unclear. HaCaT cells and 3T3 skin fibroblasts were irradiated with the 1064-nm Q-switched Nd:YAG laser at the different doses. Then, cells were collected and lysed for PCR and Western blot analysis. Cell viability was detected by Cell Counting Kit-8 (CCK-8) before and after laser irradiation. The expressions of S100A8, advanced glycosylation end product-specific receptor (RAGE) and inflammatory cytokines in two cell lines were markedly upregulated after laser treatments. The PCR, Western blot, and ELISA analysis showed the significant increase of type I and III procollagen in the 3T3 cells treated with the 1064-nm laser. Interestingly, si S100A8 effectively inhibited the expression of cytokines and collagen, while S100A8 treatments significantly increased them. P-p38 and p-p65 levels were also elevated after the 1064-nm laser irradiation, which is positively related with S100A8. Cell viability and reactive oxygen species (ROS) levels were not changed, while the content of superoxidase dismutase (SOD) in two cells was increased after laser irradiation. Our results demonstrated that the overexpression of S100A8 induced by the 1064-nm laser irradiation triggered inflammatory reactions in skin cells. The inflammatory microenvironment and improvement of skin antioxidant capacity contribute to new collagen synthesis in the skin cells. Thus, S100A8 was required for laser-induced new collagen synthesis in skin cells. p38/MAPK and NF-κB signal pathways were involved in S100A8-mediated inflammatory reactions in response to laser irradiation.     

A split-face comparison of Q-switched Nd:YAG 1064-nm laser for facial rejuvenation in Nevus of Ota patients

We aimed to investigate the efficacy and safety of using the 1064-nm Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (QSNYL) for skin rejuvenation in patients with Nevus of Ota. A retrospective, randomized, split-faced, clinical study was conducted. Twenty-nine patients with unilateral moderate to severe Nevus of Ota were enrolled. The participants completed 3–13 sessions of QSNYL treatments 3–6 months apart. Two independent physicians compared the treated and untreated sides of the face to evaluate the clearance of Nevus of Ota, the wrinkle severity rating scale (WSRS), the global aesthetic improvement scale (GAIS), and adverse event reporting. Patients’ satisfaction levels were also considered. Of the 29 patients, 28 (96.6%) achieved nearly complete pigmentation clearance. After an average of 7.76?±?2.99 sessions, statistically significant improvement in wrinkles and skin texture were observed, compared with the untreated side. The degree of skin rejuvenation was positively correlated with the number of treatment sessions. No clinically adverse effects were observed. Repeated QSNYL treatments not only remove the pigment in Nevus of Ota effectively and safely but also improve facial rejuvenation.     

Efficacy and safety of 1565-nm non-ablative fractional laser versus long-pulsed 1064-nm Nd:YAG laser in treating enlarged facial pores

Lasers in Medical Science - Facial pores are visible openings of pilosebaceous follicles, and they are one of the major factors influencing facial skin appearance. This article aims to evaluate and...     

Single-treatment skin tightening by radiofrequency and long-pulsed, 1064-nm Nd: YAG laser compared

BACKGROUND AND OBJECTIVE: To compare single-treatment facial skin tightening achieved with the current radiofrequency (RF) protocol with single-treatment tightening achieved with the long-pulsed, 1064-nm Nd:YAG laser. STUDY DESIGN/MATERIALS AND METHODS: A total of 12 patients were treated with RF energy on one side of the face and laser energy on the other. Results were evaluated on a numerical scale (0-12 with 12 = greatest enhancement) from pre- and posttreatment photographs by a blinded panel. RESULTS: Upper face improvement (posttreatment score minus pretreatment score) was essentially the same on both sides (30.2 and 31.3% improvement for laser and RF, respectively, P=0.89). Lower face improvement was greater in the laser-treated side (35.7 and 23.8% improvement for laser and RF, respectively), but the difference was not significant (P=0.074). Overall face improvement was significantly greater on the laser-treated side (47.5 and 29.8% improvement for laser and RF, respectively, P=0.028). CONCLUSION: A single high-fluence treatment with the long-pulse 1064-nm Nd:YAG laser may improve skin laxity more than a single treatment with the RF device. Further controlled split-face or very large non-self controlled studies are needed to conclusively determine the relative efficacies of the two technologies.     

Efficacy of pulsed Nd:YAG laser in the treatment of patients with knee osteoarthritis: a randomized controlled trial

The purpose of this study was to investigate the effects of pulsed Nd:YAG laser plus glucosamine/chondroitin sulfate (GCS) in patients with knee osteoarthritis (KOA) by examining changes in pain and knee function, as well as synovial thickness (ST) and femoral cartilage thickness (FCT). Sixty-seven male patients participated, with a mean (SD) age of 53.85 (4.39) years, weight of 84.01 (4.70) kg, height of 171.51 (3.96) cm, and BMI of 28.56 (1.22). Group 1 was treated with high-intensity laser therapy (HILT), GCS, and exercises (HILT?+?GCS?+?EX). Group 2 was treated with GCS plus exercises (GCS?+?EX), and group 3 received placebo laser plus exercises (PL?+?EX). The outcomes measured were pain level and functional disability using the visual analog scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), respectively. ST and FCT were measured by ultrasound examination. Statistical analyses were performed to compare differences between baseline and after 6 weeks of treatment and then after 3 months of follow-up. Statistical significance was set at p?<?0.05. VAS and WOMAC were significantly decreased in all groups after 6 weeks, with nonsignificant differences between 6 weeks and 3 months of follow-up. ST was significantly decreased in the HILT?+?GCS?+?EX group posttreatment, with nonsignificant decreases in the GCS?+?EX and PL?+?EX groups, as well as nonsignificant differences to FCT in all groups. Overall, pulsed Nd:YAG laser combined with GCS and exercises was more effective than GCS?+?EX and exercises alone in the treatment of KOA patients.     

Effects of the 532-nm and 1,064-nm Q-switched Nd:YAG lasers on collagen turnover of cultured human skin fibroblasts: a comparative study

Cultured human skin fibroblasts were irradiated twice successively with the 1.5 J/cm² of 532-nm and 1,064-nm lasers, respectively. The mRNA of procollagen, matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), heat-shock protein 70 (Hsp70), interleukin-6 (IL-6) and transforming growth factor beta (TGF-β) were analyzed at 24 and 48 h post-irradiation by using RT-PCR. Both lasers significantly increased the expression of type I and III procollagen, TIMP1, and TIMP2, but decreased MMP1 and MMP2 expression. The 1,064-nm laser initiated TGF-β expression while the 532-nm laser elicited the increase of Hsp70 and IL-6. The increase/decrease rates of procollagen, TIMPs and MMPs for the 1,064-nm laser were higher than that of the 532-nm laser. Thus, both lasers effectively accelerated collagen synthesis and inhibited collagen degradation. Collagen synthesis induced by the 1,064-nm laser might be partly due to the upregulation of TGF-β expression, while the increase of Hsp70 and IL-6 might be partly responsible for collagen synthesis stimulated by the 532-nm laser. With the parameters used in this study, the 1,064-nm infrared laser is more effective in promoting the beneficial molecular activities than the 532-nm visible laser.     

The pulsed dye laser versus the Q-switched Nd:YAG laser in laser-induced shock-wave lithotripsy

To date, there are two fairly well-established alternatives for laser-induced shock-wave lithotripsy in clinical practice. The Q-switched Nd:YAG laser is distinguished by the high-stone selectivity of its coupler systems. The necessity of a coupler system and its fairly small conversion rate of light energy into mechanical energy present serious drawbacks. Furthermore, the minimal outer diameter of the transmission system is 1.8 mm. The pulsed-dye laser can be used with a highly flexible and uncomplicated 200-micron fiber. However, the laser system itself is more complicated than the Q-switched Nd:YAG laser and requires a great deal of maintenance. Biological evaluation of damage caused by direct irradiation shows that both laser systems produce minor damage of different degrees. YAG laser lithotripsy with the optomechanical coupler was assessed in 31 patients with ureteral calculi. The instability and limited effectiveness of the fiber application system necessitated auxiliary lithotripsy methods in 14 cases. Dye-laser lithotripsy is currently being tested in clinical application. Further development, such as systems for blind application or electronic feedback mechanisms to limit adverse tissue effects, have yet to be optimized. Nevertheless, laser-induced shock-wave lithotripsy has the potential to become a standard procedure in the endourologic management of stone disease.     

A split-face,evaluator-blind randomized study on the early effects of Q-switched Nd:YAG laser plus Er:YAG micropeel (combined therapy) versus Q-switched Nd:YAG alone in light solar lentigines in Asians

Solar lentigines are a common sign of aging in Asians, who often asked for treatment. Various lasers, including Q-switched Nd:YAG and Er:YAG, have been adopted, but the results are not always satisfactory, especially for those who are relatively light in color. Our objective was to compare the early effects as well as side effects of Q-switched Nd:YAG laser plus Er:YAG micropeel (combined therapy) with those of Q-switched Nd:YAG laser (QSNY) alone in light solar lentigines in Asians. This was a split-face, evaluator-blind, randomized controlled study. A single session of treatment was performed on Asian patients with light facial lentigines. A combined treatment with QSNY and Er:YAG micropeel was allocated to one half of the face, and QSNY alone to the other half. The response to therapy was evaluated by two independent dermatologists, with standardized photographs taken 2 weeks and 1 month after the laser treatment. Patients’ satisfaction and preference in treatment were also assessed. Fifteen patients completed the study and were analyzed. Overall, a reduction in pigment was observed with both treatment arms during the study period. The degree of pigment reduction following combined therapy and QSNY alone was similar at 2 weeks’ follow-up (P?=?0.433). However, due to the higher incidence of postinflammatory hyperpigmentation (PIH) with combined therapy (73.3 vs 40 %), the degree of pigment reduction in the combined side of the face was found significantly lower than that of the QSNY-alone side at 1-month follow-up (P?=?0.014). Although our study results show that both combined therapy and QSNY alone are capable of reducing pigmentation, QSNY alone is considered to have more favorable qualities than combined treatment for light solar lentigines in Asians.     

Correction to: Efficacy of pulsed Nd:YAG laser in the treatment of patients with knee osteoarthritis: a randomized controlled trial

Lasers in Medical Science - The institutional affiliation of Dr. Aly Elsayed Mohamed Elsayed should be as follow     

Q开关1064nm激光治疗继发性色素沉着临床观察

目的：总结应用Q开关1064nm激光治疗继发性色素沉着的效果和经验。方法：25例面部色素沉着患者采用Q开关1064nm激光治疗,光斑直径6mm,能量2.5～3.5J/cm2,每周一次,共10～15次,以VISIA数字皮肤分析仪和照片评价疗效。结果：经过10～15次治疗,色素沉着均有显著性改善（P〈0.001）,治疗25例,显效16例（64.0%）,有效8例（32.0%）,总有效率为96.0%,患者耐受性好,无明显副作用。结论：Q开关1064nm激光治疗继发性色素沉着安全、有效,为其治疗提供了一种新手段。