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Sensors (Basel, Switzerland) Aug 2021In this report, using two-dimensional photonic crystals (PhC) and a one-dimensional PhC nano-beam cavity, we realized the development of all-polymeric dye-lasers on a...
In this report, using two-dimensional photonic crystals (PhC) and a one-dimensional PhC nano-beam cavity, we realized the development of all-polymeric dye-lasers on a dye-doped, suspended poly-methylmethacrylate film with a wavelength-scale thickness. In addition to the characterization of basic lasing properties, we also evaluated its capacity to serve as an attachable strain sensor. Through experimentation, we confirmed the stable lasing performances of the dye-laser attaching on a rough surface. Moreover, we also theoretically studied the wavelength responses of the utilized PhC resonators to stretching strain and further improved them via the concept of strain shaping. The attachability and high strain sensing response of the presented thin film PhC dye-lasers demonstrate their potential as attachable strain sensors.
PubMed: 34450773
DOI: 10.3390/s21165331 -
Journal of Cosmetic Dermatology Jun 2023Different devices are currently used for treating facial vascular lesions (FVL). This paper presents the aesthetic outcomes using different light-based and laser...
OBJECTIVE
Different devices are currently used for treating facial vascular lesions (FVL). This paper presents the aesthetic outcomes using different light-based and laser devices, including narrow band spectrum intense pulsed-light dye (NB-Dye-VL), Pulsed dye laser (PDL)-neodymium-doped yttrium-aluminum-garnet (Nd:YAG) dual-therapy, and either PDL or LP Nd:YAG for treating FVL in a clinical setting.
METHODS
A retrospective and single-center study conducted on subjects ≥18 years with FVL. Patients underwent treatment with either PDL + LP Nd:YAG dual-therapy, NB-Dye-VL, PDL, or LP Nd:YAG, according to the patient and lesion characteristics. The primary outcome was the weighted degree of satisfaction.
RESULTS
The cohort consisted of fourteen patients, nine women (64.3%) and five men (35.7%). The most prevalent FVL types treated were rosacea (28.6%; 4/14) and spider hemangioma (21.4%; 3/14). Seven patients underwent PDL + Nd:YAG (50.0%), three were treated with NB-Dye-VL (21.4%), and PDL or LP Nd:YAG was performed in two patients each (14.3%). Eleven patients rated their treatment outcome as excellent (78.6%), and three as very good (21.4%). Practitioners 1 and 2 classified treatment results as excellent in eight cases (57.1%) each. No serious or permanent adverse events were reported. Two (14.3%) patients, one treated with PDL and the other with PDL + LP Nd:YAG dual-therapy, had post-treatment purpura, which was successfully resolved with topical treatment after 5 and 7 days, respectively.
CONCLUSIONS
NB-Dye-VL and the PDL + LP Nd:YAG dual-therapy devices achieve excellent aesthetic outcomes for treating a wide range of FVL.
Topics: Female; Humans; Lasers, Solid-State; Retrospective Studies; Rosacea; Face; Treatment Outcome; Lasers, Dye
PubMed: 37318787
DOI: 10.1111/jocd.15772 -
Journal of Biomechanics Dec 2021Laser therapy has been widely used in the treatment of hypertrophic scars (HPS), but whether the mechanical properties of HPS tissue after laser treatment can be...
Laser therapy has been widely used in the treatment of hypertrophic scars (HPS), but whether the mechanical properties of HPS tissue after laser treatment can be restored to those of normal skin remains unclear. In this paper, the relationship between the evolution of compressive mechanical properties and histological changes of HPS tissues following three successive combined pulsed dye laser (PDL) and fractional CO laser (CO) treatments was investigated by compression tests and histological analysis. The early HPS model of rabbit ear was established by CO laser ablation. The loading-unloading tests and strain creep tests under the compression forces of 1 N, 2 N, and 3 N were carried out for normal skin, untreated HPS and HPS after different treatment times, respectively. The results showed that the compression ratio λ of all tissues revealed force dependence and rose with the increasing compression force, which was similar to the trend of most biological soft tissues. The histological changes of HPSs following laser treatment have a significant influence on the compressive mechanical response. Compared with the normal skin, the toughness and anti-deformation ability of HPS reduced due to the proliferation of collagen fibers and the destruction of elastic fibers, resulting in higher energy dissipation, compression ratio λ, and stable creep rate D, and lower elastic modulus. After three successive combined PDL/ CO laser treatments, the compressive mechanical properties and creep properties of HPS gradually approached that of the normal skin owing to the gradual restoration of the amount and distribution of collagen and elastic fibers in HPS. The results provide a new method for evaluating the clinical efficacy of laser therapy for treatment of HPS tissue.
Topics: Animals; Cicatrix, Hypertrophic; Lasers, Dye; Lasers, Gas; Low-Level Light Therapy; Rabbits; Treatment Outcome
PubMed: 34662757
DOI: 10.1016/j.jbiomech.2021.110783 -
Burns : Journal of the International... Aug 2014The purpose of this review is to investigate the use of Pulsed Dye Laser (PDL) as a therapeutic tool for hypertrophic burns scarring. The difference between keloids and... (Review)
Review
The purpose of this review is to investigate the use of Pulsed Dye Laser (PDL) as a therapeutic tool for hypertrophic burns scarring. The difference between keloids and hypertrophic scars is first described. The review then outlines the progress and assessment of hypertrophic scars for burns patients and the problem of their clinical management. The assessment using both objective and subjective measurements for complete account of hypertrophic scars is explained. The efficacy of PDL for both prevention and treatment is summarised for all hypertrophic scarring and the various laser treatment protocols in previous research is studied. The differentiation between prevention and treatment is discussed in relation to scar duration and the need for prevention rather than treatment is then proposed for intervention using PDL. The paper concludes with recommendations for future research through a prospective randomised, controlled study using 595 nm PDL in the prevention of scars with less than 6 month duration.
Topics: Burns; Cicatrix, Hypertrophic; Humans; Lasers, Dye; Low-Level Light Therapy
PubMed: 24439925
DOI: 10.1016/j.burns.2013.12.017 -
Lasers in Medical Science Dec 2019Light-based modalities appear to be effective for ameliorating surgical scar appearance; however, protocols for achieving such outcomes have yet to be established. We... (Randomized Controlled Trial)
Randomized Controlled Trial
Early intervention with pulse dye and CO ablative fractional lasers to improve cutaneous scarring post-lumpectomy: a randomized controlled trial on the impact of intervention on final cosmesis.
Light-based modalities appear to be effective for ameliorating surgical scar appearance; however, protocols for achieving such outcomes have yet to be established. We studied the safety and efficacy of a combination of pulsed dye laser (PDL) and fractional ablative CO laser (FACL) for the attenuation of post-lumpectomy scarring. We conducted a prospective, evaluator-blinded, comparative split-scar study in post-lumpectomy patients. One-half of the scar was treated with three sessions of 595-nm PDL and FACL at 1-month intervals, starting within 6 weeks after suture removal. The entire scar was also treated with standard moisturizers and silicone gels. Six months after the last treatment, the two halves of the scar were assessed by three uninvolved physicians who used the Observer Scar Assessment Scale as well as by the patients who used the Patient and Observer Scar Assessment Scale. Eighteen female patients (mean age, 51.3 years) with a mean scar length of 7.8 cm completed the treatment and follow-up. Six months after the last treatment, both the physician evaluators and the patients noted significant improvements for all assessed scar parameters in the laser-treated scar area compared with the untreated scar area. The treatment was well tolerated, and no remarkable adverse events were reported. All 18 participants were satisfied with the treated scar areas. A combination PDL and FACL protocol starting up to 6 weeks after suture removal is a safe and effective method for the attenuation of post-lumpectomy scar formation.
Topics: Cicatrix; Female; Humans; Lasers, Dye; Lasers, Gas; Mastectomy, Segmental; Middle Aged; Observer Variation; Prospective Studies; Treatment Outcome
PubMed: 31025209
DOI: 10.1007/s10103-019-02788-3 -
Spectrochimica Acta. Part A, Molecular... Dec 2022Water is being considered as an economical, safe and environmental friendly alternative solvent for dye lasers. However, the use of water in dye laser is restricted due...
Water is being considered as an economical, safe and environmental friendly alternative solvent for dye lasers. However, the use of water in dye laser is restricted due to the formation of non-emissive aggregates of dye molecules. In the present study we have explored the possibility of the use of commercially available surfactant molecules for the water based laser of Pyrromethene 597 (PM597) dye, which has emerged as an alternative for more commonly used Rhodamine dyes in dye laser systems. Our studies show that in water, PM597 forms non-emissive aggregates which can be dissociated into monomeric dye molecules by adding common surfactants. Further, the high microviscosity in the micellar media retarded energy wasting ring puckering process in the excited state of the dye leading to the increase in its emission yield and excited state lifetime to a significant extent. It has been demonstrated that the emission yield and excited state lifetime in surfactant solution is relatively higher than in ethanol, the most commonly used organic solvent for dye lasers. Lasing action has been demonstrated in the aqueous solution of dye and lasing efficiency is found to be comparable to ethanol.
Topics: Ethanol; Fluorescent Dyes; Lasers, Dye; Porphobilinogen; Solvents; Surface-Active Agents; Water
PubMed: 35901541
DOI: 10.1016/j.saa.2022.121642 -
Scientific Reports Aug 2016Intensity fluctuations in lasers are commonly studied above threshold in some special configurations (especially when emission is fed back into the cavity or when two...
Intensity fluctuations in lasers are commonly studied above threshold in some special configurations (especially when emission is fed back into the cavity or when two lasers are coupled) and related with their chaotic behaviour. Similar fluctuating instabilities are usually observed in random lasers, which are open systems with plenty of quasi-modes whose non orthogonality enables them to exchange energy and provides the sort of loss mechanism whose interplay with pumping leads to replica symmetry breaking. The latter however, had never been observed in plain cavity lasers where disorder is absent or not intentionally added. Here we show a fluctuating lasing behaviour at the lasing threshold both in solid and liquid dye lasers. Above and below a narrow range around the threshold the spectral line-shape is well correlated with the pump energy. At the threshold such correlation disappears, and the system enters a regime where emitted laser fluctuates between narrow, intense and broad, weak peaks. The immense number of modes and the reduced resonator quality favour the coupling of modes and prepares the system so that replica symmetry breaking occurs without added disorder.
PubMed: 27558968
DOI: 10.1038/srep32134 -
Journal of Cosmetic Dermatology Jan 2021The objective of this study was to investigate the clinical effects of laser therapy in treating cicatricial ectropion.
INTRODUCTION
The objective of this study was to investigate the clinical effects of laser therapy in treating cicatricial ectropion.
METHODS
Seven patients with cicatricial ectropion were entered into this clinical study. The ectropions were pretreated with the 595-nm pulsed dye laser if the scar color was red. If there was no red, the UltraPulse fractional CO laser was used and parameters were adapted according to the height of scar. MEBT/MEBO was used after laser treatment for wound healing. The degree of ectropion was measured for changes before and after treatment, and the scars were evaluated for changes in melanin, height, vascularity, and pliability using the Vancouver Scar Scale (VSS) before and after treatment.
RESULTS
All seven patients with cicatricial ectropion entered into this protocol were completely corrected after 1-2 treatment sessions. The total VSS score, as well as the score for melanin and pliability in 7 patients, showed a decrease following the treatments, and this was statistically significant (P < 0.05). The scores for height and vascularity showed a decrease following the treatments, but there was no significant difference by statistical analysis (P ≥ 0.05). There were no adverse reactions reported.
CONCLUSIONS
The treatment of cicatricial ectropion with laser therapy can not only correct the ectropion, but also improve the scars in the treatment area. Compared with the traditional repair of cicatricial ectropion, the use of fractional CO laser provides surgical precision and the advantage of a timely treatment without the need to wait for the scar to stabilize.
Topics: Cicatrix; Ectropion; Humans; Laser Therapy; Lasers, Dye; Lasers, Gas; Low-Level Light Therapy; Treatment Outcome
PubMed: 33124092
DOI: 10.1111/jocd.13821 -
Journal of Cosmetic and Laser Therapy :... Nov 2016
Topics: Cosmetic Techniques; Humans; Laser Therapy; Lasers, Dye; Minimally Invasive Surgical Procedures; Rejuvenation
PubMed: 27845619
DOI: 10.1080/14764172.2016.1242189 -
Lasers in Medical Science Jun 2024Previous clinical studies have shown that pulsed dye laser (PDL) and intense pulsed light (IPL) are effective for treating erythematotelangiectatic rosacea(ETR). This... (Randomized Controlled Trial)
Randomized Controlled Trial Comparative Study
Previous clinical studies have shown that pulsed dye laser (PDL) and intense pulsed light (IPL) are effective for treating erythematotelangiectatic rosacea(ETR). This article aims to compare the efficacy and safety of PDL and IPL at three different wavelength bands (broad-band, single-narrow-band, and dual-narrow-band) in treating ETR. Sixty subjects with ETR were randomly categorized into four groups and received one of the following laser treatments: PDL (595 nm), IPL with Delicate Pulse Light (DPL, 500-600 nm), IPL with M22 590 (590-1200 nm), or IPL with M22 vascular filter (530-650 nm and 900-1200 nm). Four treatment sessions were administered at 4-week intervals, with one follow-up session 4 weeks after the final treatment. The efficacy of the four lasers was evaluated by comparing the clinical symptom score, total effective rate, VISIA red area absolute score, and RosaQoL score before and after treatment. The safety was evaluated by comparing adverse reactions such as pain, purpura, erythematous edema, and blister. All 60 subjects completed the study. Within-group effects showed that the clinical symptom score, VISIA red area absolute score, and RosaQoL score of all four groups were significantly reduced compared to before treatment (p < 0.001). Between-group effects showed no statistically significant difference among the four laser groups. Safety analysis showed that all four lasers were safe, but the incidence of blister was higher in the M22 vascular group. Nonpurpurogenic PDL, DPL, M22 590, and M22 vascular were equally effective in treating ETR and were well-tolerated. ClinicalTrial.gov Identifier: NCT05360251.
Topics: Humans; Lasers, Dye; Female; Rosacea; Adult; Male; Middle Aged; Intense Pulsed Light Therapy; Treatment Outcome; Low-Level Light Therapy
PubMed: 38822948
DOI: 10.1007/s10103-024-04098-9