Fractional Erbium Research Articles

Combination of Q-Switched Nd:YAG and Fractional Erbium:YAG Lasers in Treatment of Melasma: A Randomized Controlled Clinical Trial.

Introduction: Ablative and nonablative lasers have been used to treat melasma. We aimed to assess and compare the combining Q-switched Nd:YAG laser (QSNYL) and fractional erbium:YAG laser (FEYL) with QSNYL alone in treatment of melasma. Methods: This randomized controlled clinical trial was performed in our Research Center during 2013-2014. Women with melasma and without a history of keloid formation, hypersensitivity to hydroquinone, or pigmentary changes due to laser therapy were randomly allocated to receive four sessions of either QSNYL-FEYL combination or QSNYL alone. All patients received topical treatment with Kligman's formula. Before laser therapy and 4 weeks after the last treatment session, patients' skin was assessed for changes in skin color, melanin content, and erythema intensity of melasma lesions quantitatively. Results: Finally, 21 patients in QSNYL-FEYL and 20 in QSNYL group (mean age, 38.57 [5.60] and 42.60 [8.44] years, respectively) completed study. The skin color had become lighter in both groups (mean [SD] percentage change of 56.95 [40.29] and 29.25 [13.20] in QSNYL-FEYL and QSNYL groups, respectively) with significantly better results in QSNYL-FEYL group (P = 0.006). Percentage of decrease of melanin content was significantly higher in QSNYL-FEYL group (22.01 [10.67] vs. 7.69 [4.75]; P < 0.001). After adjustment for baseline values, the post treatment intensity of erythema was significantly lower in QSNYL-FEYL group (P < 0.001). The patients reported no adverse events. Conclusion: QSNYL-FEYL was significantly more effective in decreasing melanin content of lesions than QSNYL and led to a lighter skin.

Combined Treatment with 1,550-nm Fractional Erbium:Glass Fiber and 2,940-nm Fractional Erbium:YAG Lasers for Atrophic Scars

Combined Treatment with 1,550-nm Fractional Erbium:Glass Fiber and 2,940-nm Fractional Erbium:YAG Lasers for Atrophic Scars

Combination therapy for onychomycosis using a fractional 2940-nm Er:YAG laser and 5% amorolfine lacquer.

Onychomycosis remains difficult to cure by traditional methods. The aim of this study was to evaluate the efficacy of combination therapy with a fractional erbium yttrium aluminum garnet (Er:YAG) laser and 5% amorolfine lacquer on onychomycosis. Nine patients with bilateral nails affected by distal and lateral subungual onychomycosis were included. The bilateral nails of each patient were divided into two groups. The 20 affected nails on one side of each patient as group 1 were treated with a fractional Er:YAG laser once a week and 5% amorolfine lacquer twice weekly, while the 20 nails on the symmetrical side of each patient as group 2 were treated with amorolfine lacquer only. The laser treatment was conducted at weeks 1, 2, 3, 4, 8, and 12 in group 1. The clinical improvement, onychomycosis severity index (OSI), maximum linear clear nail growth (MLCNG), and mycological cure rate were evaluated. At week 24, 18 of 20 (90%) nails in group 1 had achieved obvious clinical responses. The mean OSI score showed a significant decrease (5.24) and the average MLCNG was 3.1mm in group 1. At week 24, 15 of 20 (75%) nails achieved a negative mycological examination in group 1, compared with four of 20 (20%) nails in group 2. The treatments were well-tolerated by most patients. This clinical study suggests that combination therapy of a fractional 2940-nm Er:YAG laser and 5% amorolfine lacquer is an effective, safe, and convenient treatment method for onychomycosis.

Non-ablative fractional laser assists cutaneous delivery of small- and macro-molecules with minimal bacterial infection risk

Use of the ablative laser has been approved to enhance topical drug penetration. Investigation into the usefulness of the non-ablative laser for assisting drug delivery is very limited. In this study, we explored the safety and efficacy of the non-ablative fractional erbium:glass (Er:glass) laser as an enhancement approach to promote drug permeation. Both pig and nude mouse skins were employed as transport barriers. We histologically examined the skin structure after laser exposure. The permeants of 5-aminolevulinic acid (ALA), imiquimod, tretinoin, peptide, dextrans and quantum dots (QD) were used to evaluate in vitro and in vivo skin passage. The fractional laser selectively created an array of photothermal dots deep into the dermis with the preservation of the stratum corneum and epidermis. The barrier function of the skin could be recovered 8–60h post-irradiation depending on the laser spot densities. The application of the laser caused no local infection of Staphylococcus aureus and Pseudomonas aeruginosa. Compared to intact skin, ALA flux was enhanced up to 1200-fold after laser exposure. The penetration enhancement level by the laser was decreased following the increase of permeant lipophilicity. The skin accumulation of tretinoin, an extremely lipophilic drug, showed only a 2-fold elevation by laser irradiation. The laser promoted peptide penetration 10-fold compared to the control skin. Skin delivery of dextrans with a molecular weight (MW) of at least 40kDa could be achieved with the Er:glass laser. QD with a diameter of 20nm penetrated into the skin with the assistance of the non-ablative laser. The confocal microscopic images indicated the perpendicular and lateral diffusions of dextrans and nanoparticles via laser-created microscopic thermal zones. Controlled Er:glass laser irradiation offers a valid enhancement strategy to topically administer the permeants with a wide MW and lipophilicity range.

Skin healing and collagen changes of rats after fractional erbium:yttrium aluminum garnet laser: observation by reflectance confocal microscopy with confirmed histological evidence.

The fractional erbium:yttrium aluminum garnet (Er:YAG) laser is widely applied. Microstructural changes after laser treatment have been observed with histopathology. Epidermal and dermal microstructures have also been analyzed using reflectance confocal microscopy (RCM). However, no studies have compared these two types of microstructural changes in the same subject at multiple time points after irradiation, and it is unclear if these two types of changes are consistent. We use RCM to observe the effect of different laser energies on skin healing and collagen changes in the skin of Sprague-Dawley rats that had been irradiated by fractional Er:YAG lasering at different energies. RCM was used to observe skin healing and detect collagen changes at different time points. Collagen changes were observed using hematoxylin and eosin (H&E) staining and quantitatively analyzed by western blot. RCM showed that, irrespective of laser energy, microscopic treatment zones (MTZs) were larger at 1day after irradiation. The MTZs then reduced in size from 3 to 7days after irradiation. The higher the energy, the larger the MTZ area. The amount of collagen also increased with time from 1day to 8weeks. However, the increase in the collagen amount on both RCM and H&E staining was not influenced by the laser energy. Western blotting confirmed that the amount of type I and type III collagens increased over time, but there were no significant differences between the different energy groups (p > 0.05). In conclusion, RCM is a reliable technique for observing and evaluating skin healing and collagen expression after laser irradiation.

712 Biological effects of non-ablative fractional erbium glass laser treatment and gene regulatory response in human 3D skin models

712 Biological effects of non-ablative fractional erbium glass laser treatment and gene regulatory response in human 3D skin models

Effects of non-ablative fractional erbium glass laser treatment on gene regulation in human three-dimensional skin models.

Clinical experiences with non-ablative fractional erbium glass laser therapy have demonstrated promising results for dermal remodelling and for the indications of striae, surgical scars and acne scars. So far, molecular effects on human skin following treatment with these laser systems have not been elucidated. Our aim was to investigate laser-induced effects on skin morphology and to analyse molecular effects on gene regulation. Therefore, human three-dimensional (3D) organotypic skin models were irradiated with non-ablative fractional erbium glass laser systems enabling qRT-PCR, microarray and histological studies at same and different time points. A decreased mRNA expression of matrix metalloproteinases (MMPs) 3 and 9 was observed 3 days after treatment. MMP3 also remained downregulated on protein level, whereas the expression of other MMPs like MMP9 was recovered or even upregulated 5 days after irradiation. Inflammatory gene regulatory responses measured by the expression of chemokine (C-X-C motif) ligands (CXCL1, 2, 5, 6) and interleukin expression (IL8) were predominantly reduced. Epidermal differentiation markers such as loricrin, filaggrin-1 and filaggrin-2 were upregulated by both tested laser optics, indicating a potential epidermal involvement. These effects were also shown on protein level in the immunofluorescence analysis. This novel standardised laser-treated human 3D skin model proves useful for monitoring time-dependent ex vivo effects of various laser systems on gene expression and human skin morphology. Our study reveals erbium glass laser-induced regulations of MMP and interleukin expression. We speculate that these alterations on gene expression level could play a role for dermal remodelling, anti-inflammatory effects and increased epidermal differentiation. Our finding may have implications for further understanding of the molecular mechanism of erbium glass laser-induced effects on human skin.

Current Status of Fractional Laser Resurfacing.

Fractional lasers were first developed based on observations of lasers designed for hair transplantation. In 2007, ablative fractional laser resurfacing was introduced. The fractionation allowed deeper tissue penetration, leading to greater tissue contraction, collagen production and tissue remodeling. Since then, fractional erbium:YAG resurfacing lasers have also been introduced. These lasers have yielded excellent results in treating photoaging, acne scarring, and dyschromia. With the adjustment of microspot density, pulse duration, number of passes, and fluence, the surgeon can adjust the treatment effects. These lasers have allowed surgeons to treat patients with higher Fitzpatrick skin types (types IV to VI) and greater individualize treatments to various facial subunits. Immunohistochemical analysis has demonstrated remodeling effects of the tissues for several months, producing longer lasting results. Adjuvant treatments are also under investigation, including concomitant face-lift, product deposition, and platelet-rich plasma. Finally, there is a short recovery time from treatment with these lasers, allowing patients to resume regular activities more quickly. Although there is a relatively high safety profile for ablative fractionated lasers, surgeons should be aware of the limitations of specific treatments and the associated risks and complications.

Intense pulsed light, near infrared pulsed light, and fractional laser combination therapy for skin rejuvenation in Asian subjects: a prospective multi-center study in China.

Ablative skin rejuvenation therapies have limitations for Asian people, including post-inflammatory hyperpigmentation and long down time. Non-ablative lasers are safer but have limited efficacy. This study is to investigate the safety and efficacy of a combination therapy consisting of intense pulsed light (IPL), near infrared (NIR) light, and fractional erbium YAG (Er:YAG) laser for skin rejuvenation in Asian people. This study recruited 113 subjects from six sites in China. Subjects were randomly assigned to a full-face group, who received combination therapy, and split-face groups, in which one half of the face received combination therapy and the other half received IPL monotherapy. Each subject received five treatment sessions during a period of 90 days. Subjects were followed up at 1 and 3 months post last treatment. Three months after last treatment, the full-face group (n = 57) had a global improvement rate of 29 % and 29 % for wrinkles, 32 % for skin texture, 33 % for pigment spots, 28 % for pore size, respectively. For patients in the split-face groups (n = 54), monotherapy side had a global improvement rate of 23 % and 20 % for wrinkles, 27 % for skin texture, 25 % for pigment spots, 25 % for pore size, respectively. Both combination therapy and monotherapy resulted in significant improvements at the follow-up visits compared to baseline (P < 0.001). Combination therapy showed significantly greater improvements compared to monotherapy at two follow-up visits (P < 0.05). Combination therapy is a safe and more effective strategy than IPL monotherapy for skin rejuvenation in Asian people.

A full-face study evaluating the safety of a 2940-nm fractional ablative erbium laser for skin resurfacing in Brazilian patients with Fitzpatrick skin types II-VI

A full-face study evaluating the safety of a 2940-nm fractional ablative erbium laser for skin resurfacing in Brazilian patients with Fitzpatrick skin types II-VI

Effect topical hyaluronic acid after ablative fractional erbium laser resurfacing for lip rejuvenation

Effect topical hyaluronic acid after ablative fractional erbium laser resurfacing for lip rejuvenation

Topically applied methotrexate is rapidly delivered into skin by fractional laser ablation

Objectives: Methotrexate (MTX) is a chemotherapeutic and anti-inflammatory drug that may cause systemic adverse effects. This study investigated kinetics and biodistribution of MTX delivered topically by ablative fractional laser (AFXL).Methods: In vitro passive diffusion of 10 mg/ml MTX (1 w/v%) was measured from 0.25 to 24 h through AFXL-processed and intact porcine skin in Franz Cells (n = 46). A 2,940 nm fractional Erbium Yttrium Aluminium Garnet laser generated mid-dermal microchannels at 2.4% density, and 256 mJ/microchannel. HPLC quantified MTX-concentrations in extracts from mid-dermal skin sections, donor and receiver compartments. Fluorescence microscopy of UVC-activated MTX-fluorescence and desorption electro-spray ionization mass spectrometry imaging (DESI-MSI) evaluated MTX biodistribution.Results: AFXL-processed skin facilitated rapid MTX delivery through cone-shaped microchannels of 690 µm ablation depth, lined by the 47 µm thermal coagulation zone (CZ). Quantitatively, MTX was detectable by HPLC in mid-dermis after 15 min, significantly exceeded deposition in intact skin after 1.5 h, and saturated skin after 7 h at a 10-fold increased MTX-deposition versus intact skin (3.08 vs 0.30 mg/cm3, p = 0.002). Transdermal permeation was < 1.5% of applied MTX before skin saturation, and increased up to 8.0% after 24 h. Qualitatively, MTX distributed into CZ within 15 min (p = 0.015) and further into surrounding dermal tissue after 1.5 h (p = 0.004). After skin saturation at 7 h, MTX fluorescence intensities in CZ and tissue were similar and DESI-MSI confirmed MTX biodistribution throughout the mid-dermal skin section.Conclusions: MTX absorbs rapidly into mid-dermis of AFXL-processed skin with minimal transdermal permeation until skin saturation, suggesting a possible alternative to systemic MTX for some skin disorders.

Treatment of dilated pores with 1410-nm fractional erbium-doped fiber laser.

Dilated pores can be an early sign of skin aging and are a significant cosmetic concern. The 1410-nm wavelength is optimal for superficial dermal treatments up to 650 μm deep. The aim of the present study was to evaluate the clinical effectiveness and safety of the fractional erbium-doped fiber 1410-nm laser in the treatment of dilated pores. Fifteen patients with dilated facial pores underwent three laser treatments at 3-week intervals. Posttreatment skin responses and side effects were assessed at treatment and follow-up visits by study physicians. Clinical effectiveness of treatment was assessed by both study physicians and patients 3 months after the final laser treatment using a quartile grading scale. Histological examination was performed using biopsy samples taken at baseline (pretreatment) and 3 months after the last treatment. This study showed that greater than 51 % improvement in dilated pores was demonstrated in 14 of 15 patients after three sessions of laser treatments. Improvements in skin texture, tone, and smoothness were reported in all patients. Treatment was well tolerated in all patients, with no unanticipated side effects. This study demonstrates that the 1410-nm fractional erbium fiber laser is effective and safe for treatment of dilated facial pores in Fitzpatrick skin types III-IV.

Treatment of keloids with laser-assisted topical steroid delivery: a retrospective study of 23 cases.

Topical or intralesional corticosteroids are referred to as gold standard treatments for keloids. Recent studies showed that ablative fractional laser (AFL) treatment facilitates delivery of topical drug deeply into the skin by creating vertical channels. The objective of the present study was to assess the ablative erbium laser in fractionated mode, combined with topical high potent corticosteroid cream for treating resistant keloid scars. We conducted a retrospective study in the laser center of the Department of Dermatology (University Hospital of Nice, France), from January 2010 to June 2012, on patients with keloids who were resistant to a first-line of treatment. A 2940-nm ablative fractional erbium laser was used. Topical betamethasone cream was applied twice a day under occlusion with transparent film dressings. A total of 23 patients with 70 keloids were treated from January 2010 to June 2012. The median percentage of improvement was 50% (range -43 to 84). The mean follow-up was 8 months (range 3-18), and a recurrence was observed for eight lesions (22%). Although this observation warrants a prospective comparative evaluation, it supports the interest of the laser-assisted delivery of steroids for treating keloids scars.

Randomized split-face controlled study to evaluate 1550-nm fractionated erbium glass laser for treatment of acne vulgaris--an image analysis evaluation.

Novel and promising results in acne treatment with infrared lasers have been reported. The 1,550-nm erbium glass laser is one of the infrared lasers that may be useful in the treatment of acne. The aim of this study was to evaluate the efficacy of an erbium glass laser in treatment of active acne and to study the effect of this type of laser on sebaceous glands. Twenty-four patients with active acne lesions were treated using 1,550-nm (30-40 mJ) fractional erbium glass laser. Every patient received 4 sessions with a 2-week interval. Follow-up was done every 3 months for 1 year. The image analyzer computer system was used to measure the sebaceous gland size. A significant reduction (p < .0001) in the mean count of lesions was observed after treatment and in the follow-up period. A significant reduction in the size of sebaceous glands was also evident after laser treatment. Treatment of active acne with the 1,550-nm erbium glass laser is effective. Papules, pustules, and nodules all respond well to therapy. The sebaceous gland size decreased significantly, which accounts for the long remission period.

Histologic comparison of microscopic treatment zones induced by fractional lasers and radiofrequency

Introduction: Fractional photothermolysis induces microscopic, localized thermal injury in the skin surrounded by undamaged viable tissue in order to promote wound healing. Objective: This study evaluated acute histologic changes following each single pass of various fractional lasers and radiofrequency (RF). Methods: Three male domestic swine were used. We used fractional Erbium:glass (Er:glass), Erbium:yttrium-aluminum-garnet (Er:YAG), CO2 lasers, and fractional ablative microplasma RF. We analyzed features and average values of the diameter, depth, and vertical sectional areas treated with each kind of laser and RF. Results: The microscopic treatment zone (MTZ) of fractional Er:glass resulted in separation of dermoepidermal junction with no ablative zone. Fractional Er:YAG provided the most superficial and broad MTZ with little thermal collateral damage. Fractional CO2 resulted in a narrow and deep “cone”-like MTZ. Fractional RF resulted in a superficial and broad “crater”-like MTZ. Conclusions: This study provides the first comparison of MTZs induced by various fractional lasers and RF. These data provide basic information on proper laser and RF options. We think that these findings could be a good reference for information about fractional laser-assisted drug delivery.

Non-ablative fractional laser provides long-term improvement of mature burn scars--a randomized controlled trial with histological assessment.

Non-ablative fractional laser-treatment is evolving for burn scars. The objective of this study was to evaluate clinical and histological long-term outcome of 1,540 nm fractional Erbium: Glass laser, targeting superficial, and deep components of mature burn scars. Side-by-side scar-areas were randomized to untreated control or three monthly non-ablative fractional laser-treatments using superficial and extra-deep handpieces. Patient follow-up were at 1, 3, and 6 months. Primary outcome was improvement in overall scar-appearance on a modified-Patient-and-Observer-Scar-Assessment-Scale (mPOSAS, 1 = "normal skin", 10 = "worst imaginable scar"). Secondary outcomes included histology, patient satisfaction (0-10), patient-assessed improvement, and safety. Study was completed by 17 of 20 randomized patients with normotrophic (n = 11), hypertrophic (n = 5) or atrophic (n = 1) scars. Scar-appearance improved from laser-treatments (P < 0.001 vs. untreated) and histology at 6 months supported collagen-remodeling. Improvement appeared continuously during the post-operative period (mPOSAS baseline: 7 [5-8], 6 months: 4 [3-5] P = < 0.001). At 6 months, patients were satisfied with treatment (6 [3-9]) and 82% reported improved scar-texture. Treatments caused mild to moderate pain (4 [2-7]). Adverse effects decreased during follow-up and at final assessment, discrete erythema, hyperpigmentation or imprints from laser-grid were present in 11 patients. No patients experienced worsening of scar-appearance. Combined superficial and deep non-ablative fractional laser-treatments induce long-term clinical and histological improvement of mature burn scars.

Nonablative fractional laser as a tool to facilitate skin penetration of 5-aminolaevulinic acid with minimal skin disruption: a preliminary study

Effective penetration of a photosensitizer is an essential step in photodynamic therapy (PDT). There have been trials of several methods, including laser treatment, to facilitate prompt and sufficiently deep transdermal drug delivery. To evaluate the effects of nonablative fractional laser pretreatment on 5-aminolaevulinic acid (ALA) penetration of the skin. Twelve treatment areas (1 × 1 cm(2)) on the backs of 10 healthy male subjects were mapped. Test areas received laser treatment followed by incubation with ALA. Laser treatment was performed with a 1550 nm fractional erbium glass laser, and the laser energy was set to 20 or 50 mJ with a spot density of 50 cm(-2). ALA incubation time was 30, 60 or 180 min. Porphyrin fluorescence was measured. Sites pretreated with nonablative fractional laser showed significantly increased porphyrin fluorescence compared with nonpretreated areas. Laser energy strength and ALA incubation time were positively correlated with ALA absorption. Nonablative fractional laser treatment effectively enhanced ALA skin penetration. Pretreatment with a nonablative fractional laser can be used for ALA-PDT to achieve higher ALA uptake and shortened ALA incubation times with minimal skin barrier disruption compared with ablative laser.

Fractional Erbium laser in the treatment of photoaging: randomized comparative, clinical and histopathological study of ablative (2940nm) vs. non-ablative (1540nm) methods after 3 months.

BACKGROUNDFractional non-ablative lasers keep the epidermis intact, while fractional ablative lasers remove it, making them theoretically more effective.OBJECTIVESTo evaluate the clinical and histological alterations induced by fractional photothermolysis for treating photoaging, comparing the possible equivalence of multiple sessions of 1540nm Erbium, to one session of 2940nm Erbium.METHODSEighteen patients (mean age 55.9) completed the treatment with three sessions of 1540nm fractional Erbium laser on one side of the face (50 mJ/mB, 15ms, 2 passes), and one session of 2940nm on the other side (5mJ/mB, 0.25ms, 2 passes). Biopsies were performed before and 3 months after treatment. Clinical, histological and morphometric evaluations were carried out.RESULTSAll patients presented clinical improvement with no statistically significant difference (p> 0.05) between the treated sides. Histopathology revealed a new organization of collagen and elastic fibers, accompanied by edema, which was more evident with the 2940nm laser. This finding was confirmed by morphometry, which showed a decrease in collagen density for both treatments, with a statistical significance for the 2940nm laser (p > 0.001).CONCLUSIONSThree 1540nm sessions were clinically equivalent to one 2940nm session. The edema probably contributed to the positive results after three months, togheter with the new collagen and elastic fibers organization. The greater edema after the 2940nm session indicates that dermal remodeling takes longer than with 1540nm. It is possible that this histological superiority relates to a more prolonged effect, but a cohort longer than three months is needed to confirm that supposition.

Fractional erbium 2940-nm laser and acoustic pressure wave ultrasound module for transepidermal delivery of cosmetic antiaging ingredients for wrinkles and pigment changes: A randomized, split face side by side study

Fractional erbium 2940-nm laser and acoustic pressure wave ultrasound module for transepidermal delivery of cosmetic antiaging ingredients for wrinkles and pigment changes: A randomized, split face side by side study