Fractional Er Research Articles

Comparison of the effectiveness of nonablative fractional laser versus ablative fractional laser in thyroidectomy scar prevention: A pilot study

A scar is a mark that remains after the healing of a wound or other morbid processes. In the past, treatment was mainly focused on severe scarring, such as the hypertrophic and burn scars. However, scars from relatively minor wounds can also be stressful. The site of an open thyroidectomy is the anterior neck, a prominently exposed part of the body, where postoperative scarring can cause patients distress. The cosmetic outcome of the scar after thyroidectomy is of particular importance to women, who constitute the majority of patients with thyroid disease. Active prevention is more likely to yield better cosmetic results and would require fewer treatment sessions and less expense than scar revision procedures. Many interventions have been proposed, but there is yet no universal consensus on optimal treatment. Recently, focus has been made on ‘laser scar prevention’, where various types of lasers have been used to improve the appearance of scars. The purpose of this study was to improve the appearance of scars, by laser intervention of the wound healing process. In this pilot study, we comparatively examined the effect of non-ablative 1550-nm fractional Er: glass laser and ablative 2940-nm fractional Er: YAG laser on fresh surgical scars of patients with Fitzpatrick skin type III-IV.

Effect of fractional Er:YAG laser on skin collagen proliferation.

Objective To investigate the histological changes of normal human skin after fixed irradiation with multiple-pulse fractional Er:YAG laser.Methods After hair removal,the upper arms of 7 healthy volunteers were consecutively irradiated with multiple-pulse fractional Er:YAG laser.Tissue samples were resected from the irradiated skin at 1,24,48,72 hours,on day 5,7,15,and 30 after the irradiation.Hematoxylin and eosin(HE)staining and Masson staining were performed to observe the histological changes and collagen proliferation respectively.Immunohistochemical staining was used to detect the expression of heat shock protein(HSP)70 and 47.Results The consecutive irradiation with multi-pulse fractional Er:YAG laser generated an array of tapering microscopic treatment zones(MTZs)of gasification and ablation in the upper arm skin.After the irradiation,inflammation developed in the microscopic lesions with the epithelization of epidermal cells within 7 days; local dermal collagen was renewed and remodelled during the 7th to 30th day.HSP70 expression peaked as early as 48 hours after the treatment and maintained until the 7th day,while the high expression of HSP47 persisted from the 15th to 30th day after irradiation.Conclusion The fixed,multiplepulse and fractional Er:YAG laser irradiation can reach the deep dermis,and induce the local proliferation of dermal collagen. Key words: Lasers; Fractional photothermolysis; HSP70 heat-shock proteins; HSP47 heat-shock proteins; Collagen

The effect of a 1550 nm fractional erbium–glass laser in female pattern hair loss

Female pattern hair loss (FPHL) is the most common cause of hair loss in women, and its prevalence increases with advancing age. Affected women may experience psychological distress and social withdrawal. A variety of laser and light sources have been tried for treatment of hair loss, and some success has been reported. The purpose of this study was to determine the efficacy and safety of a 1550 nm fractional erbium-glass laser in treatment of female pattern hair loss. Twenty eight ethnic South Korean patients with varying degrees of FPHL were enrolled in the study. Patients received ten treatments with a 1550 nm fractional Er:Glass Laser (Mosaic, Lutronic Co., Ltd, Seoul, South Korea) at 2-weeks intervals using the same parameters (5-10 mm tip, 6 mJ pulse energy, 800 spot/cm(2) density, static mode). Phototrichogram and global photographs were taken at baseline and at the end of laser treatment, and analysed for changes in hair density and hair shaft diameter. Global photographs underwent blinded review by three independent dermatologists using a 7-point scale. Patients also answered questionnaires assessing hair growth throughout the study. All adverse effects were reported during the study. Twenty seven patients completed a 5-month schedule of laser treatment. One patient was excluded during treatment due to occurrence of alopecia areata. At the initial visit, mean hair density was 100 ± 14/cm(2) , and mean hair thickness was 58 ± 12 μm. After 5 months of laser treatment, hair density showed a marked increase to 157 ± 28/cm(2) (P < 0.001), and hair thickness also increased to 75 ± 13 μm (P < 0.001). Global photographs showed improvement in 24 (87.5%) of the 27 patients. Two patients (7.4%) reported mild pruritus after laser treatment; however, these resolved within 2 h. A 1550 nm fractional erbium-glass laser irradiation may be an effective and safe treatment option for women with female pattern hair loss.

Ablative Fractional Erbium-Doped Yttrium Aluminum Garnet Laser with Coagulation Mode for the Treatment of Atrophic Acne Scars in Asian Skin

The introduction of fractional photothermolysis (FP) for the treatment of atrophic acne scars has been proven to provide satisfactory results. For severe atrophic acne scarring, nonablative FP achieves fair improvement and takes multiple treatment sessions. Ablative fractional resurfacing provides an alternative modality with greater satisfaction. To evaluate the effectiveness and safety of the ablative fractional 2,940-nm erbium-doped yttrium aluminum garnet (Er:YAG) laser with coagulation mode for the treatment of atrophic facial acne scars in Asian skin. Thirty-four patients aged 19 to 44 (mean 34.2) with Fitzpatrick skin types III and IV, received one ablative fractional 2,940-nm Er:YAG laser treatment with an adjustable coagulation mode and were followed for 3 months. Physician evaluation and patient satisfaction were graded on a 4-point scale. Side effects were recorded at each follow-up visit. Almost three-quarters of the patients rated their satisfaction as good to excellent (score of 3 or 4). All patients experienced short downtime, and the incidence of postinflammatory hyperpigmentation was low (3.0%). The ablative fractional Er:YAG laser with coagulation mode is recommended for the treatment of moderate to severe atrophic acne scars, with acceptable downtime and high satisfaction in Asian patients.

A study of multiple full-face treatments with low-energy settings of a 2940-nm Er:YAG fractionated laser

Background and objective: Fractional Er:YAG 2940-nm laser resurfacing is a relatively new approach to the treatment of photodamaged skin. Typically, this approach uses fairly high delivered energies in order to create ‘microscopic wounds’ of tissue coagulation at various dermal depths. The purpose of this study was to evaluate the efficacy, safety and tolerability of low-energy, multiple-treatment, fractional Er:YAG laser resurfacing for the treatment of photoaged skin. Methods: Sixteen subjects with photoaged skin received six, lower-fluence laser treatments with a 2940-nm wavelength Er:YAG laser, using a fractionated handpiece and a maximum energy of 30 mJ per micro-spot. Subject satisfaction, treatment tolerability, and subject outcome assessment were performed. Results: Of the 12 subjects who completed the trial, all recorded improvement in their treated skin; half reported over 50% improvement. Most patients reported none or only mild stinging and burning during and after treatment. There was no downtime associated with the procedure. No adverse events were reported. Patient satisfaction rates were high. Conclusion: Low-energy, multiple treatment, 2940-nm Er:YAG laser resurfacing with this novel device is a safe and well-tolerated method for the treatment of superficial to moderate photoaged skin.

Treatment of Striae Distensae with Nonablative Fractional Laser versus Ablative CO2Fractional Laser: A Randomized Controlled Trial

BackgroundStriae distensae are atrophic dermal scars with overlying epidermal atrophy causing significant cosmetic concern. Although a variety of laser and light sources have been used for the treatment of striae distensae, to date no definite 'gold standard' treatment modality has been determined.ObjectiveTo assess and compare the efficacy and safety of nonablative fractional photothermolysis and ablative CO2 fractional laser resurfacing in the treatment of striae distensae.MethodsTwenty-four ethnic South Korean patients with varying degrees of atrophic striae alba in the abdomen were enrolled in a randomized blind split study. The patients were treated with 1,550 nm fractional Er:Glass laser and ablative fractional CO2 laser resurfacing. Each half of the abdominal lesion was randomly selected and treated three times at intervals of 4-weeks using the same parameters. Digital photography was conducted and skin elasticity and the width of the widest striae in each subject were measured at the baseline and 4 weeks after the final treatment. Clinical improvement was assessed by comparing pre- and post-treatment clinical photographs by two blinded physicians and participant satisfaction rates were evaluated. Skin biopsies were taken from three participants. All adverse effects were reported during the study.ResultsAlthough they do not statistically differ, both treatments with nonablative fractional laser and ablative CO2 fractional laser showed a significant clinical and histopathologic improvement of striae distensae over pretreatment sites.ConclusionThese results support the use of nonablative fractional laser and ablative CO2 fractional laser as effective and safe treatment modalities for striae distensae of Asian skin. However, neither treatment showed any greater clinical improvement than the other treatment.

Comparative study between the Er:YAG and Nd:YAG lasers in treatment of post acne scar

Abstract Background: Acne vulgaris is a very common skin disorder that affects virtually all individuals at least once during life. Acne scarring can have a great impact on the psychosocial life for the young adults. Er:YAG lasers has been used in the treatment of acne scarring. The results, however, produced open wounds with significant downtime. In contrast, nonablative remodeling lasers, (1064-nm Nd:YAG lasers) can reduce acne scarring without significant downtime, but at lower efficacies. Recently, resurfacing with fractional microscopic delivery of high energies to targeted depths in the dermis has made possible significant clinical improvements often approaching that of ablative lasers without any reports of permanent hypo pigmentation or scarring. So the aim of this study was to determine the best modality in treatment of acne scars. Patients and methods: 26 patients with mild to moderate facial acne scarring were included in this study, they were divided into 3 groups using traditional ablative Er:YAG laser, Nd:YAG laser and fractional Er:YAG laser respectively. Histopathological specimen were taken for objective assessment, and subjectively by patient satisfaction, doctor satisfaction. Results: Showed that the use of fractional Er:YAG laser had the greatest clinical improvements in scar treatment, with mild erythema without any downtime. With edema not lasting for more than 1 day. No crusting, scabbing formation, or infection was seen in this group. Conclusion: Er:YAG laser fractional photocoagulation is a promising option for the treatment of atrophic post acne scars, avoiding the adverse effects of ablative laser procedures with improving the limited efficacy of the nonablative ones.

In Vivo Histopathologic Comparison of the Acute Injury Following Treatment With Five Fractional Ablative Laser Devices

Both erbium (Er:YAG) and carbon dioxide (CO(2)) devices are commonly-used, efficient laser systems for aggressive skin resurfacing procedures. The devices each have different adjustable parameters (density, spot size, number of pulses, pattern, etc) and utilize variable energy capabilities to tailor individual treatments depending on the skin pathology and goals of treatment. Overall, the consensus has been that multiple-pass erbium treatments needed for efficacious wrinkle reduction had similar downtime and comorbidity to the traditional CO(2) treatments. Unfortunately, there were limited data comparing the histological differences and changes throughout the wound-healing process over time between the two treatment methods. The authors compare the difference in injury following treatment with five novel fractional ablative laser systems in vivo. Differences in damage pattern, treatment depth, and degree of surrounding cellular injury following treatment with each device at common clinical settings are evaluated in a side-by-side histopathologic comparison. Prior to planned excisional surgery, the panni of 20 abdominoplasty patients were treated with five novel ablative fractional carbon dioxide or Er:YAG laser systems at various clinical parameters, in accordance with the manufacturers' treatment guidelines. After tissue removal two to four hours later, the skin was biopsied and processed for histopathologic evaluation. Specimens were stained with hematoxylin and eosin, along with a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) assay, to highlight the degree of irreversible cellular injury. The acute damage profile differed between the fractional Er:YAG and CO(2) devices with respect to depth of penetration and extension of coagulation surrounding the microcolumns. The damage pattern was dependent on the parameters set with each device (eg, fluence, pulses, density, pulse width). The TUNEL-stained sections demonstrated more collateral cellular injury surrounding the ablated columns with the CO(2) devices than with the Er:YAG systems. Following treatment with the fractional Er:YAG and CO(2) devices, deep tissue injury with various coagulative and ablative properties was observed, and it was confirmed that carbon dioxide and erbium devices result in different patterns of injury. As such, each may be better suited for different clinical situations. It is important for practitioners to understand the limitations of a specific device, as well as the tissue injury following a given treatment pattern or protocol, to appropriately tailor their treatment algorithm for a given patient. This extensive histopathologic evaluation of the acute characterization of injury across devices is helpful in clarifying the differences/similarities in laser-tissue interaction following treatment in an in vivo human model.

Ablative fractional lasers (CO2 and Er:YAG): A randomized controlled double‐blind split‐face trial of the treatment of peri‐orbital rhytides

Ablative fractional lasers were introduced for treating facial rhytides in an attempt to achieve results comparable to traditional ablative resurfacing but with fewer side effects. However, there is conflicting evidence on how well this goal has generally been achieved as well as on the comparative value of fractional CO(2) and Er:YAG lasers. The present study compares these modalities in a randomized controlled double-blind split-face study design. Twenty-eight patients were enrolled and completed the entire study. Patients were randomly assigned to receive a single treatment on each side of the peri-orbital region, one with a fractional CO(2) and one with a fractional Er:YAG laser. The evaluation included the profilometric measurement of wrinkle depth, the Fitzpatrick wrinkle score (both before and 3 months after treatment) as well as the assessment of side effects and patient satisfaction (1, 3, 6 days and 3 months after treatment). Both modalities showed a roughly equivalent effect. Wrinkle depth and Fitzpatrick score were reduced by approximately 20% and 10%, respectively, with no appreciable difference between lasers. Side effects and discomfort were slightly more pronounced after Er:YAG treatment in the first few days, but in the later course there were more complaints following CO(2) laser treatment. Patient satisfaction was fair and the majority of patients would have undergone the treatment again without a clear preference for either method. According to the present study, a single ablative fractional treatment session has an appreciable yet limited effect on peri-orbital rhytides. When fractional CO(2) and Er:YAG lasers are used in such a manner that there are comparable post-operative healing periods, comparable cosmetic improvement occurs. Multiple sessions may be required for full effect, which cancels out the proposed advantage of fractional methods, that is, fewer side effects and less down time.

SPF-RR sequential photothermal fractional resurfacing and remodeling with the variable pulse Er:YAG laser and scanner-assisted Nd:YAG laser

Background and objective: Many different lasers, polychromatic high-intensity light sources (PCLs), and RF devices have claimed clinical efficacy in rejuvenating the skin. In this study, the sequential combination of two different laser wavelengths was evaluated to produce reliably significant clinical improvements optimizing treatment parameters. Methods: The left volar aspects of the forearms of four volunteers were treated with nine different parameter settings using a variable pulsewidth fractional Er:YAG 2940-nm laser with and without air cooling. The pain perception level was recorded on a 0–10 point scale (0=No pain; 10=Most severe pain). Three evaluations were made: during treatment, immediately after treatment, and 5 minutes after treatment. The same investigation was made on the right volar aspects of the same four volunteers using a short-pulse, random pattern, 3-mm spot, scanner-assisted Nd-YAG 1064-nm laser at 0.3 ms pulsewidth at seven different parameter settings. Clinical evaluations were made concerning erythema and edema 3 days after treatment, as well as pre-operative and 60 days postoperative skin texture plus color uniformity. Considering that the majority of cosmetic patients are willing to accept a relatively short and uneventful downtime (2–4 days according to a study we are presently conducting) and do prefer to limit their intra- and postoperative pain to a minimum, the best combination of clinical improvement matching these two important parameters were selected for our study. A treatment strategy combining two sequential passes of long-pulse Nd:YAG laser (Nd:YAG-LP) at 0.3 and 35 ms followed by two passes of long-pulse fractional Er:YAG laser (Er:YAG-FT) at 600 μs was designed to treat the facial regions of 10 volunteers affected by a combination of intrinsic (chrono-) and extrinsic (mostly photo-) aging. The pain perception level was recorded on a 0–10 scale (0=No pain; 10=Most severe pain). Three evaluations were made: during, immediately after, and 5 minutes after treatment. Erythema and edema were evaluated on a 0–3 point scale (0=No clinical signs; 3=Severe Clinical signs) at 7, 15 and 30 days. Improvements were determined by blind evaluation of photographs before, at 4 weeks, and at 8 weeks following treatments. Patient satisfaction was also evaluated on a 0–4 point scale (0=No satisfaction; 4=Excellent perceived improvement, 76–100%). Results: At the 30-day follow-up, participants had clinically detectable improvements of facial telangiectasias (1–25%), lentigines (25–50%), diffuse dyspigmentation (25–75%), fine lines (25–75%), and skin texture (25–75%). Clinical improvements were maintained at the 60-day follow-up, demonstrating the prolonged photothermally induced biological effect on skin function and texture. All volunteers confirmed their willingness to undergo the same procedure again to maintain and possibly improve their clinical results. Further clinical evaluations at 4 and 6 months will therefore be needed to identify a suitably convenient interval between two consecutive procedures. Conclusion: The present study demonstrates objective and subjective improvements in fine lines, skin texture and dyspigmentation of facial skin after one sequential non-ablative and ablative laser treatment combining two different laser sources (Nd:YAG laser + Er:YAG laser).

Correlation of histological findings of single session Er:YAG skin fractional resurfacing with various passes and energies and the possible clinical implications

Ablative fractional resurfacing shows promise for skin resurfacing and tightening and also to improve treatment of epidermal and dermal pigmentary disorders. This study aimed at determining any correlation between epidermal ablation and effects on the dermis when using an Er:YAG laser in ablative fractional resurfacing mode. Ten female subjects participated in the study, mean age 52 years, Skin phototypes: 1 Fitzpatrick type II; 8 type III and 1 type IV. The degree of wrinkles (Glogau scale II or III) was similar in all cases. The laser used was the Pixel Er:YAG system (Alma Lasertrade mark, Israel) which delivers the laser beam via a hand-piece equipped with a beam splitter to divide the 2,940 nm beam into various microbeams of 850 microm in diameter in an 11 mmx11 mm treatment area. Using a constant energy of 1,400 mJ/cm(2), on a test area of 4 cmx2 cm. Two, 4, 6, and 8 passes on the preauricular area of the face were evaluated immediately after treatment. In all cases, the handpiece was kept in the same position, and rotated slightly around its perpendicular axis between passes, then moved on to the next spot. Biopsies were performed and tissue samples were routinely processed and stained with hematoxylin and eosin (H&E). No patient reported any noticeable discomfort, even at 8 passes. The histological findings revealed that, independent of the degree of the wrinkles, more laser passes produced more ablative removal of the epidermis. Residual thermal damage (RTD) with 2 laser passes was not observed but with 4 and 6 passes increased thermal effects and vacuole formation in the epidermal cells were noticed. With 8 laser passes, total epidermal removal was seen together with frank RTD-related changes in the upper part of the papillary dermis. In this study, we have demonstrated that high density fractional Er:YAG laser energy in a single session with multiple passes targeted not only the skin surface with elimination of the epidermis, but could also achieve heat deposition in the upper dermis. When performing ablative fractional resurfacing with an Er:YAG laser, treatment of varying degrees of damage could be achieved by varying the number of passes.