The role of lasers and intense pulsed light technology in dermatology

The therapeutic effect of IPL on children with refractory seasonal allergic conjunctivitis

OBJECTIVE

To observe the effectiveness of intense pulsed light(IPL) treatment as an adjuvant treatment of refractory seasonal allergic conjunctivitis in children.

METHODS

A total of 31 patients with refractory seasonal allergic conjunctivitis who did not respond well to anti-allergic drug treatment were randomly selected to receive drug therapy combined with IPL treatment (17 patients) and drug treatment alone (14 patients) for 1 week, and the ocular surface symptom questionnaire and ocular surface sign score were performed before and after treatment, respectively.

RESULT

After treatment, the IPL group had significantly lower scores in eye rubbing, blinking, eye itching, discharge, tearing, and total scores than before treatment (P < 0.05), while there was no significant difference in foreign body sense scores before and after treatment (P > 0.05). There were no significant differences in eye rubbing, blinking, eye itching, discharge, foreign body sensation, tearing, and total score between the control group after treatment (P > 0.05). After treatment, the scores of ocular signs in the IPL group and the control group were lower than those before treatment, and the difference was statistically significant (P < 0.01).

CONCLUSION

IPL therapy is effective in improving ocular surface symptoms in children with refractory seasonal allergic conjunctivitis, especially in suppressing eye itching, with good results.

Use of a fractional 1570-nm diode laser scanner for nonablative face and neck rejuvenation

BACKGROUND

The use of non-ablative fractionated lasers for skin rejuvenation has been proven to be effective in improving skin texture, and has become popular due to minimal wounding, significantly shorter recovery times and decreased adverse effects.

OBJECTIVE

To retrospectively analyze improvement in skin texture in healthy women aged over 18 years with Fitzpatrick skin type II-IV.

METHODS

Participants received 3 facial and/or neck treatments with the 1570-nm fractional scanning diode laser at one-month intervals. Three months after the last treatment session two blinded evaluators assessed skin improvement using before and after photos. Pain and patient satisfaction were recorded.

RESULTS

Sixteen women with a mean age of 45.4 ± 4.1 years (range 35-50 years) and skin type II-IV were included in the analysis. All 16 participants received facial treatments and seven (43.8%) also received neck treatments. Three months follow-up evaluation showed that the majority of participants had at least a visible change in the treated areas. Mean pain score was low and decreased with each treatment session.

CONCLUSION

Skin treatment using fractional scanning 1570-nm diode laser improves skin laxity in women with skin types II-IV. Larger studies are warranted to further clarify the efficacy and safety of this modality.

Laser-Induced Koebner-Related Skin Reactions: A Clinical Overview

The Koebner phenomenon (KP), also known as the isomorphic response, describes the process by which new lesions that are clinically and histologically identical to a patient's existing skin disease develop following trauma. Many skin diseases exhibit this characteristic, with variations that include possible, questionable, and pseudo-Koebner reactions, with the latter category occurring due to infectious agents seeding at a trauma site. Laser application, a type of controlled skin injury used for improving cutaneous lesions and skin rejuvenation, is also considered a form of trauma. This raises the question of whether controlled thermal injury can be regarded as a type of mechanical trauma capable of producing Koebner-related reactions. We conducted a literature review of cases or studies to identify laser-induced dermatoses that correspond to Koebner-related or pathergy reaction categories. As a whole, we identified nine case reports on true KPs, two cases on possible KPs, seventeen cases on laser-induced questionable KPs comprising cases of vasculitis, eczema or Meyerson reactions, and eruptive squamous atypia cases (ESA) as well as two pseudo-Koebner cases involving wart occurrences at laser application sites. Laser-induced Koebner reactions highlight several aspects of the KP. Firstly, the type of mechanical damage influences disease promotion, as different lasers are associated with different KPs. For example, hair removal lasers are linked with true and questionable KPs such as vasculitis while resurfacing lasers were found to be more connected with ESA occurrence. Secondly, the laser target is significant, with vascular laser application for port-wine stains tending to result in eczematous reactions, while hair follicle destruction can frequently lead to true KPs. Thirdly, the number of sessions matters; true KPs and eruptive squamous atypia questionable KPs typically appear after one to two sessions, whereas eczematous reactions require more sessions (at least four). Additionally, skin phototype is crucial, with darker phototypes showing a higher KP frequency as laser treatment for hypertrichosis relies on melanin absorption in the hair bulge or bulb for follicle destruction, as chromophore competes with the abundant melanin in the epidermis. Further research with larger-scale studies into trauma-specific Koebner reactions is vital for refining treatment protocols, minimizing post-laser adverse effects, and improving dermatological care outcomes.

Use of a fractional 1570-nm diode laser scanner for non-ablative face and neck rejuvenation

BACKGROUND

The use of non-ablative fractionated lasers for skin rejuvenation has been proven to be effective in improving skin texture, and has become popular due to minimal wounding, significantly shorter recovery times and decreased adverse effects.

OBJECTIVE

To retrospectively analyze improvement in skin texture in healthy women aged over 18 years with Fitzpatrick skin types II-IV.

METHODS

Participants received three facial and/or neck treatments with the 1570-nm fractional scanning diode laser at 1-month intervals. Three months after the last treatment session two blinded evaluators assessed skin improvement using before and after photos. Pain and patient satisfaction were recorded.

RESULTS

Sixteen women with a mean age of 45.4 ± 4.1 years (range 35-50 years) and skin type II-IV were included in the analysis. All 16 participants received facial treatments and seven (43.8%) also received neck treatments. Three months follow-up evaluation showed that the majority of participants had a visible change in the treated areas. Mean pain score was low and decreased with each treatment session.

CONCLUSION

Skin treatment using fractional scanning 1570-nm diode laser improves skin laxity in women with skin types II-IV. Larger studies are warranted to further clarify the efficacy and safety of this modality.

Intense Pulsed Light (IPL) for the treatment of vascular and pigmented lesions

BACKGROUND

IPL devices emit a wide range of wavelengths that can be absorbed by different chromophores in the skin. Selective destruction of a specific chromophore with minimal side effects is controlled by wavelength, pulse duration, and fluence.

AIM

This study aims to evaluate the treatment of vascular and pigmented lesions using narrow-band Intense Pulsed Light (IPL) with Advanced Fluorescence Technology (AFT), which offers more efficient energy usage per pulse to increase safety, and improve clinical outcomes.

METHODS

A retrospective analysis of data from 100 patients treated with narrow-band IPL for vascular and pigmented lesions. Efficacy was measured by the Global Aesthetic Improvement Scale (GAIS) and Patient Satisfaction Scale (0-10). Safety was assessed by evaluating pain levels and adverse events.

RESULTS

Mean GAIS scores were 8.02 ± 0.84 for vascular and 8.14 ± 0.9 for pigmented lesions with no significant difference between groups (p=0.49, α=0.05). Patient satisfaction correlated with GAIS scores (correlation coefficient 0.8). No pain was reported and two patients experienced temporary and transient side effects.

CONCLUSION

Overall, the advanced IPL treatments provided favorable outcomes for vascular and pigmented lesions.

A Preliminary Study on Quantitative Analysis of Collagen and Apoptosis Related Protein on 1064 nm Laser-Induced Skin Injury

To investigate the associated factors concerning collagen and the expression of apoptosis-related proteins in porcine skin injuries induced by laser exposure, live pig skin was irradiated at multiple spots one time, using a grid-array method with a 1064 nm laser at different power outputs. The healing process of the laser-treated areas, alterations in collagen structure, and changes in apoptosis were continuously observed and analyzed from 6 h to 28 days post-irradiation. On the 28th day following exposure, wound contraction and recovery were notably sluggish in the medium-high dose group, displaying more premature and delicate type III collagen within the newly regenerated tissues. The collagen density in these groups was roughly 37-58% of that in the normal group. Between days 14 and 28 after irradiation, there was a substantial rise in apoptotic cell count in the forming epidermis and granulation tissue of the medium-high dose group, in contrast to the normal group. Notably, the expression of proapoptotic proteins Bax, caspase-3, and caspase-9 surged significantly 14 days after irradiation in the medium-high dose group and persisted at elevated levels on the 28th day. During the later stage of wound healing, augmented apoptotic cell population and insufficient collagen generation in the newly generated skin tissue of the medium-high dose group were closely associated with delayed wound recovery.

Autologous Nanofat Injection Combined with Fractional CO2 Laser in the Treatment of Atrophic Acne Scars

Background

Atrophic acne scarring is a widely prevalent condition and one of the most distressing complications of acne vulgaris. Numerous options with variable outcomes are available for the treatment of acne scarring. Laser is considered a first-line therapy for acne scars, and recently there has been a growing interest in using stem cells and their derivatives for treating acne scars. In addition, combined therapeutic modalities often achieve more satisfactory results than a single treatment.

Objective

We tried to evaluate the role of nanofat and fractional CO2 laser as a combined treatment approach for atrophic acne scarring.

Methods

Twenty-five patients with atrophic acne scarring were enrolled. They received a single session of intradermal nanofat injection, at different points 1 cm apart, for acne scars. Two weeks later, they were treated with three sessions of fractional CO2 laser at monthly intervals. Patients were evaluated three months after the last session using the quantitative Goodman and Baron scoring system. Pain, side effects, and patients' satisfaction were also evaluated.

Results

There were two males and 23 females with a mean age of 25.96 years. Their skin type ranged between Fitzpatrick skin type III, IV, and V. Boxcar scars were the most common scar type in 13 patients (52%). After treatment, there was a significant reduction (p <0.05) in the quantitative Goodman and Baron scores. The improvement was more evident in rolling scars. Seven patients reported significant improvement, and 12 reported marked improvement.

Conclusion

This study showed that combining nanofat and fractional CO2 laser is a safe and effective treatment modality for atrophic acne scars.

Therapeutic effect of intense pulsed light on different types of chalazion in children

This study aims to investigate the effectiveness of Intense Pulsed Light (IPL) therapy for chalazion treatment while also exploring potential variations in sensitivity among different types of chalazion. A total of 149 patients were selected to receive tobramycin combined with IPL treatment and tobramycin combined with hot compress. The treatment groups were divided into cystic type and granulomatous type according to different clinical manifestations. The course of treatment was 3 weeks. The improvement was based on the ultrasound measurement of the masses reduction of more than 50% or disappearance. In the IPL group, 17 (22.67%) cases were cured, 39 (52.00%) were effective, and 19 (25.33%) were ineffective. This includes: cystic type was cured in 3 (15.79%), effective in 5 (26.32%) cases, ineffective in 11 (57.89%) cases; granulomatous type was cured in 14 (25.00%) cases, effective in 34 (60.71%) cases, ineffective in 8 (14.29%) cases. In the hot compress group, 5 (6.76%) cases were cured, 16 (21.62%) cases were effective and 53 (71.62%) cases were ineffective. The cystic type was cured in 2 (8.00%) cases, effective in 3 (12.00%) cases and ineffective in 20 (80.00%) cases; the granulomatous type was cured in 3 (6.12%) cases, effective in 13 (26.53%) cases and ineffective in 33 (67.35%) cases. The cure rate and efficacy rate of IPL treatment is higher than that of hot compress treatment, the treatment effect of IPL treatment on granulomatous chalazion is better than that on cystic type.

Interaction of the AKT and β-catenin signalling pathways and the influence of photobiomodulation on cellular signalling proteins in diabetic wound healing

The induction of a cells destiny is a tightly controlled process that is regulated through communication between the matrix and cell signalling proteins. Cell signalling activates distinctive subsections of target genes, and different signalling pathways may be used repeatedly in different settings. A range of different signalling pathways are activated during the wound healing process, and dysregulated cellular signalling may lead to reduced cell function and the development of chronic wounds. Diabetic wounds are chronic and are characterised by the inability of skin cells to act in response to reparative inducements. Serine/threonine kinase, protein kinase B or AKT (PKB/AKT), is a central connection in cell signalling induced by growth factors, cytokines and other cellular inducements, and is one of the critical pathways that regulate cellular proliferation, survival, and quiescence. AKT interacts with a variety of other pathway proteins including glycogen synthase kinase 3 beta (GSK3β) and β-catenin. Novel methodologies based on comprehensive knowledge of activated signalling pathways and their interaction during normal or chronic wound healing can facilitate quicker and efficient diabetic wound healing. In this review, we focus on interaction of the AKT and β-catenin signalling pathways and the influence of photobiomodulation on cellular signalling proteins in diabetic wound healing.

Evaluating the efficacy of Nd:YAG fourth harmonic (266 nm) in comparison with ArF excimer (193 nm) in laser corneal reshaping: ex vivo pilot study

PURPOSE

Laser corneal reshaping is a common eye surgery utilized to overcome many vision disorders. Different UV laser wavelengths can be effective in the treatment. However, the ArF excimer laser (193 nm) is the most commonly used due to its high absorption in the cornea. In the current study, we investigate the efficacy of applying a solid-state laser (Nd:YAG fourth harmonic at 266 nm) for the corneal reshaping procedure.

METHODS

The utilized laser is generated using an optical setup based on a BBO nonlinear crystal which converts the Q-switched laser (532 nm) to its fourth harmonic (266 nm). Different pulse energies were applied with the same number of the shoots on ex vivo rabbit corneas, and the histological effect is studied. Moreover, the possible thermal damage on the treated corneal tissues was inspected via electron microscope. Additionally, the DNA damage on the corneal cells due to the application of the proposed laser was examined and compared with the existing technology (ArF Excimer laser at 193 nm) using the comet assay.

RESULTS

The histological examination revealed an appropriate ablation result with the minimum thermal effect at 1.5 mJ and 2.0 mJ. The overall results show that applying 50-shoots of the 1.5-mJ pulse energy using the proposed 266-nm solid-state laser produces the optimum ablation effect with the minimum thermal damage, and almost the same DNA damage occurred using the commercial 193-nm ArF excimer laser.

CONCLUSION

Solid-state laser at 266 nm could be a good alternative to the common 193-nm excimer laser for corneal reshaping procedures.

Deep learning-based optical approach for skin analysis of melanin and hemoglobin distribution

SIGNIFICANCE

Melanin and hemoglobin have been measured as important diagnostic indicators of facial skin conditions for aesthetic and diagnostic purposes. Commercial clinical equipment provides reliable analysis results, but it has several drawbacks: exclusive to the acquisition system, expensive, and computationally intensive.

AIM

We propose an approach to alleviate those drawbacks using a deep learning model trained to solve the forward problem of light-tissue interactions. The model is structurally extensible for various light sources and cameras and maintains the input image resolution for medical applications.

APPROACH

A facial image is divided into multiple patches and decomposed into melanin, hemoglobin, shading, and specular maps. The outputs are reconstructed into a facial image by solving the forward problem over skin areas. As learning progresses, the difference between the reconstructed image and input image is reduced, resulting in the melanin and hemoglobin maps becoming closer to their distribution of the input image.

RESULTS

The proposed approach was evaluated on 30 subjects using the professional clinical system, VISIA VAESTRO. The correlation coefficients for melanin and hemoglobin were found to be 0.932 and 0.857, respectively. Additionally, this approach was applied to simulated images with varying amounts of melanin and hemoglobin.

CONCLUSION

The proposed approach showed high correlation with the clinical system for analyzing melanin and hemoglobin distribution, indicating its potential for accurate diagnosis. Further calibration studies using clinical equipment can enhance its diagnostic ability. The structurally extensible model makes it a promising tool for various image acquisition conditions.

Successful Treatment of Minocycline-Induced Facial Hyperpigmentation with a Combination of Chemical Peels and Intense Pulsed Light

Minocycline is a tetracycline derivative antibiotic commonly used to treat acne, rosacea, and other inflammatory skin conditions. Taking minocycline risks inducing skin pigmentation. If minocycline-induced hyperpigmentation is not treated, it may take months to years for the symptoms to subside after discontinuation of the drug, or the hyperpigmentation may never disappear completely, which can lead to cosmetic anxiety and affect people's quality of life. Previous treatment options for hyperpigmentation were mainly q-switched nd: YAG, ruby, and alexandrite lasers. This article reports a case of facial hyperpigmentation caused by minocycline using a combination of chemical peel and intense pulsed light in a patient with eosinophilic cellulitis (Wells syndrome) who was taking oral minocycline. This case suggests combining chemical peel and intense pulsed light is an effective treatment option for minocycline-induced hyperpigmentation.

Assessment of the Effectiveness of Treatment of Vascular Lesions within the Facial Skin with a Laser with a Wavelength of 532 nm Based on Photographic Diagnostics with the Use of Polarized Light

Aesthetic medicine is a dynamically developing field of medicine. It has an impact not only on the improvement of the external appearance, but also on health and quality of life. Currently, vascular changes affect many patients and significantly diminish the condition of the skin. The development of modern laser therapy has contributed to the successful management of multiple skin conditions, among them vascular lesions. The aim of our study was to show the efficacy of repetitive 532 nm laser therapy in reducing vascular skin lesions located on the facial area. Observations were possible due to the implementation of System of Skin Analysis. We retrospectively analyzed the records of 120 patients (100 women and 20 men) using "VISIA" Skin Analysis System after 532 nm laser therapy. Treatment with the use of the 532 nm vascular laser turned out to be effective in reducing vascular changes in both women and men. The skin phototypes did not significantly affect the therapy efficacy. Neither the age of patients nor number of laser sessions affect therapy efficacy. 532 nm laser therapy is effective in reducing vascular skin lesions located in the face area.

A retrospective study of the efficacy of intense pulsed light delivered by the Lacrystim® for meibomian gland dysfunction therapy

Background

Meibomian gland dysfunction is the most common etiology of dry eye disease worldwide and intense pulsed light appears to be a promising treatment with encouraging results. Lacrystim® is a new IPL device (CE marking in 2019) and no studies have yet been published on it. We propose the first study on this device with an objective assessment of its efficacy and an extended follow-up over 6 months.

Methods

Patients presenting with a dry eye disease (DED) with stable mild to moderate MGD and having received Lacrystim® treatment between june 2019 and june 2020 were included. 3 IPL sessions were performed at D0, D15 and D45 with 4 shots per side at a fluence of 8 mJ/cm2. DED clinical evaluation was performed at D0, D15, D45, 3rd month and 6th month: Oxford scale and break up time, Schirmer test and Ocular Surface Disease Index (OSDI) questionnaire. Lacrydiag® imaging device carried out an objective examination of tear film: interferometry, meibography, tear meniscus height and non-invasive break up time (NIBUT). The primary endpoint was the evolution in NIBUT between the first visit D0 and 3rd month. Data collection was done retrospectively. Statistical analysis was done using a linear mixed-effects model and a non-parametric linear mixed-effects model (R software).

Results

Forthy five consecutive patients were included. NIBUT significantly increased between D0 and 3rd month: mean difference of 1.63 seconds, IC95% [0.51; 2.62], (p = 0.002) with a prolonged effect at 6th month. OSDI and OXFORD scores and interferometry were also significantly improved at 3rd month and 6th month. There was no significant change in BUT, Schirmer test and tear meniscus height. No adverse event was noted.

Conclusions

IPL delivered by Lacrystim® appears effective and safe to treat MGD although a randomized controlled trial is needed to validate its results.

Trial registration

This work was approved by a local ethics committee “Terre d’éthique” (institutional review board number: IRBN672019/CHUSTE) and registered on the clinicaltrial.gov website (NCT04147962, 01/11/2019).

Lasers for the treatment of erythema, dyspigmentation, and decreased elasticity in macular acne scars: a systematic review

Scarring is one of the most esthetically challenging and psychologically burdening aspects following inflammatory acne. While "macular" disease is the scar subtype with the least complicated outcome, its phase can be regarded as the most defining in the ultimate scar appearance. Moreover, with lasers recently gaining much popularity in the scientific community for managing several dermatologic conditions, we aimed to evaluate whether they would lead to significant benefits. For this systematic review, four databases consisting of PubMed, Scopus, Embase, and Web of Science were searched using a comprehensive string, with the data from the relevant yet eligible identified records qualitatively synthesized. After investigating the data obtained from the nine included studies, we found the utilized lasers, namely neodymium-doped yttrium aluminum garnet, fractional carbon dioxide, pulsed dye, erbium:glass, pro-yellow, and high-power optically pumped semiconductor, to be highly effective in managing the erythematous or dyspigmented appearance with the reduced elasticity also significantly improving. Moreover, the adverse events were both bearable and minimal, and transient. However, the degree of improvement each type of scar demonstrated following laser therapy varied based on the laser used. Neodymium-doped yttrium aluminum garnet, fractional carbon dioxide, and pulsed dye are the most commonly investigated lasers for managing macular acne scars, demonstrating eye-catching capabilities in managing either erythema or dyspigmentation. However, we still recommend that further comparative interventional studies be carried out, while the intended outcomes also assessed with objective measures for further clarification.

Laser Management and Safety in Dermatology

Lasers have acquired a wide application in dermatology due to the demand for more precise and less invasive treatments. Their indications are multiple, with proven effectiveness. Nevertheless, their use has some risks. The objective of our review is to summarize the technical and practical characteristics related to the use of lasers to ensure their management, effectiveness, and safety.

Effects of 445 nm, 520 nm, and 638 nm Laser Irradiation on the Dermal Cells

Background: The invention of non-ionizing emission devices revolutionized science, medicine, industry, and the military. Currently, different laser systems are commonly used, generating the potential threat of excessive radiation exposure, which can lead to adverse health effects. Skin is the organ most exposed to laser irradiation; therefore, this study aims to evaluate the effects of 445 nm, 520 nm, and 638 nm non-ionizing irradiation on keratinocytes and fibroblasts. Methods: Keratinocytes and fibroblasts were exposed to a different fluency of 445 nm, 520 nm, and 638 nm laser irradiation. In addition, viability, type of cell death, cell cycle distribution, and proliferation rates were investigated. Results: The 445 nm irradiation was cytotoxic to BJ-5ta (≥58.7 J/cm²) but not to Ker-CT cells. Exposure influenced the cell cycle distribution of Ker-CT (≥61.2 J/cm²) and BJ-5ta (≥27.6 J/cm²) cells, as well as the Bj-5ta proliferation rate (≥50.5 J/cm²). The 520 nm irradiation was cytotoxic to BJ-5ta (≥468.4 J/cm²) and Ker-CT (≥385.7 J/cm²) cells. Cell cycle distribution (≥27.6 J/cm²) of Ker-CT cells was also affected. The 638 nm irradiation was cytotoxic to BJ-5ta and Ker-CT cells (≥151.5 J/cm²). The proliferation rate and cell cycle distribution of BJ-5ta (≥192.9 J/cm²) and Ker-CT (13.8 and 41.3 J/cm²) cells were also affected. Conclusions: At high fluences, 455 nm, 520 nm, and 638 nm irradiation, representing blue, green, and red light spectra, are hazardous to keratinocytes and fibroblasts. However, laser irradiation may benefit the cells at low fluences by modulating the cell cycle and proliferation rate.

Light-Based Devices for the Treatment of Facial Erythema and Telangiectasia

Facial erythema is one of the most common outpatient complaints in dermatology. There are various causes of facial erythema and several devices are available for its treatment. Pulsed dye laser (PDL) and intense pulsed light (IPL) are the two common light devices used for these conditions. In this review, we evaluated the literature to assess efficacy of IPL versus PDL in facial erythema and telangiectasia. We searched published articles including clinical trials or reviews articles, case series, and case reports. Electronic databases (MEDLINE and PubMed) were searched to retrieve the articles. Reference lists of selected articles were also considered for the review. Articles published in English language until June 2021 were considered for this review.

Laser Therapy for the Treatment of Morphea: A Systematic Review of Literature

Morphea, also known as localized scleroderma (LoS), comprises a set of autoimmune sclerotic skin diseases. It is characterized by inflammation and limited thickening and induration of the skin; however, in some cases, deeper tissues might also be involved. Although morphea is not considered a life-threatening disease, the apparent cosmetic disfigurement, functional or psychosocial impairment affects multiple fields of patients’ quality of life. Therapy for LoS is often unsatisfactory with numerous treatments that have only limited effectiveness or considerable side effects. Due to the advances in the application of lasers and their possible beneficial effects, the aim of this study is to review the reported usage of laser in morphea. We present a systematic review of available literature, performed with MEDLINE, Cinahl, Central, Scopus, Web of Science, and Google Scholar databases. We identified a total of twenty relevant studies (MEDLINE n = 10, Cinahl n = 1, Central n = 0, Scopus n = 2, Web of Science n = 5, Google Scholar n = 2) using laser therapy for LoS. Eight studies were focused on the use of PDL, six on fractional lasers (CO₂ and Er:YAG), four on excimer, and two on either alexandrite or Nd:YAG.

Home-based devices in dermatology: a systematic review of safety and efficacy

There is increasing demand for home-based devices for the treatment of dermatologic conditions and cosmesis. Commercially available devices include intense pulsed light, laser diodes, radiofrequency, light-emitting diodes, and ultraviolet B phototherapy. The objective of this report is to evaluate the current evidence regarding the efficacy and safety of home-based devices for the treatment of skin conditions. A systematic search of PubMed, Embase, and Cinahl was conducted on November 9, 2020 using PRISMA guidelines. Original research articles that investigated the efficacy and safety of home-based devices for dermatologic use were included. Bibliographies were screened for additional relevant articles. Strength of evidence was graded using the Oxford Centre for Evidence-Based Medicine guidelines. Clinical recommendations were then made based on the quality of the existing literature. After review, 37 clinical trials were included—19 were randomized controlled trials, 16 were case series, and 2 were non-randomized controlled trials. Ultimately, from our analysis, we recommend the home-based use of intense pulsed light for hair removal, laser diodes for androgenic alopecia, low power radiofrequency for rhytides and wrinkles, and light-emitting diodes for acne vulgaris. Trials investigating ultraviolet B phototherapy for psoriasis revealed mixed evidence for home treatments compared to clinic treatments. All devices had favorable safety profiles with few significant adverse events. Limitations to our review include a limited number of randomized controlled trials as well as a lack of data on the long-term efficacy and safety of each device.

Effect of Different Wavelengths of Laser Irradiation on the Skin Cells

The invention of systems enabling the emission of waves of a certain length and intensity has revolutionized many areas of life, including medicine. Currently, the use of devices emitting laser light is not only an indispensable but also a necessary element of many diagnostic procedures. It also contributed to the development of new techniques for the treatment of diseases that are difficult to heal. The use of lasers in industry and medicine may be associated with a higher incidence of excessive radiation exposure, which can lead to injury to the body. The most exposed to laser irradiation is the skin tissue. The low dose laser irradiation is currently used for the treatment of various skin diseases. Therefore appropriate knowledge of the effects of lasers irradiation on the dermal cells’ metabolism is necessary. Here we present current knowledge on the clinical and molecular effects of irradiation of different wavelengths of light (ultraviolet (UV), blue, green, red, and infrared (IR) on the dermal cells.

Mechanistic aspects of photobiomodulation therapy in the nervous system

Photobiomodulation therapy (PBMT) previously known as low-level laser therapy (LLLT) has been used for over 30 years, to treat neurological diseases. Low-powered lasers are commonly used for clinical applications, although recently LEDs have become popular. Due to the growing application of this type of laser in brain and neural-related diseases, this review focuses on the mechanisms of laser action. The most important points to consider include the photon absorption by intracellular structures; the effect on the oxidative state of cells; and the effect on the expression of proteins involved in oxidative stress, inflammation, pain, and neuronal growth.

Assessment of Effects of Laser Light Combining Three Wavelengths (450, 520 and 640 nm) on Temperature Increase and Depth of Tissue Lesions in an Ex Vivo Study

Background: Lasers are widely used in medicine in soft and hard tissue surgeries and biostimulation. Studies found in literature typically compare the effects of single-wavelength lasers on tissues or cell cultures. In our study, we used a diode laser capable of emitting three components of visible light (640 nm, red; 520 nm, green; 450 nm, blue) and combining them in a single beam. The aim of the study was to assess the effects of laser radiation in the visible spectrum on tissue in vitro, depending on the wavelength and pulse width. Methods: All irradiations were performed using the same output power (1.5 W). We used various duty cycles: 10, 50, 80 and 100% with 100 Hz frequency. Maximum superficial temperature, rate of temperature increase and lesion depth were investigated. Results: Maximum superficial temperature was observed for 450 + 520 nm irradiation (100% duty cycle). The highest rate of increase of temperature was noted for 450 + 520 nm (100% duty cycle). Maximum lesion depth was observed in case of three-wavelength irradiation (450 + 520 + 640 nm) for 100, 80 and 50% duty cycles. Conclusions: The synergistic effect of two-wavelength (450 + 520 nm) irradiation was observed in case of maximum temperature measurement. The deepest depth of lesion was noted after three-wavelength irradiation (450 + 520 + 640 nm).

Generic outcome set for the international registry on Laser trEAtments in Dermatology (LEAD): a protocol for a Delphi study to achieve consensus on what to measure

INTRODUCTION

While laser technology has expanded the armamentarium of treatment for various skin diseases during the past years, heterogeneity in study outcomes hampers comparability and appropriate evidence synthesis. Part of these issues can be addressed by developing a generic outcome set. Using the Delphi method, this study aims to seek consensus between key stakeholders on relevant generic outcomes (what to measure) for implementation in the international registry on Laser trEAtments in Dermatology (LEAD). The registry is focused on collecting research data on various laser treatments for skin disorders.

METHODS AND ANALYSIS

By reviewing the literature and involvement of key stakeholder groups and adult patients in need or after laser surgery and health professionals, a preliminary list of outcomes will be generated and categorised into domains. Using these outcomes, an international three-round Delphi study will be performed to rate the importance of outcomes in the selection of a generic outcome set. Participants are allowed to provide new outcomes to the preliminary list for revisions during the first Delphi round. Finally, results will be discussed during a consensus meeting to agree on generic outcomes to be used in the LEAD registry.

ETHICS AND DISSEMINATION

An ethics approval was not applicable (W19_290 # 18.336). The study is registered with the Cochrane Skin Core OUtcome Set INitiative) and the Core Outcome Measures in Effectiveness Trials initiative. Procedures will be conducted according to the Declaration of Helsinki. The findings will be disseminated through peer-reviewed publications and conference presentations.

Improved telangiectasia and reduced recurrence rate of rosacea after treatment with 540 nm-wavelength intense pulsed light: A prospective randomized controlled trial with a 2-year follow-up

The aim of the present study was to evaluate the clinical efficacy and safety of 540 nm-wavelength intense pulsed light (IPL) for the treatment of telangiectasia in late-stage rosacea. Between July 2013 and January 2016, patients with rosacea who tested positive for Demodex folliculorum were recruited. Patients received anti-mite therapy and were then randomly apportioned to receive either three 540 nm-IPL treatments at 4-week intervals (IPL group), or no treatment (control group). Telangiectasia was assessed by the same clinician at baseline and at follow-up intervals over 2 years, where ≥90% clearance of telangiectasia was considered to indicate effective treatment. The rates of effective treatment, improvement (≥30% clearance) and recurrence (original or neo-location) were compared in both groups. After 33 patients were lost during follow-up, the IPL and control groups were comprised of 107 and 120 patients for the final analysis, respectively. The rates of effective treatment and total efficacy in the IPL group (66.36 and 95.33%, respectively) were found to be significantly higher compared with those of the control group (0 and 30.83%, respectively). By contrast, the rates of recurrence were found to be lower in the IPL group (8.41%) compared with the control group (48.33%). Redness-to-blisters associated with IPL treatment (9.7% of analyzed patients) subsided within one week and hyperpigmentation (1.9%) within 3 months. To conclude, treatment with 540 nm-IPL improved facial telangiectasia in late-stage rosacea that remained after sequential anti-mite therapy and effectively reduced the recurrence of rosacea. The present study was registered into the Chinese Clinical Trial Registry under the title ‘Sequential therapy for mites folliculitis’ (Trial registration number: ChiCTR-IPR-15006451; approved May 27, 2015).

Laser-induced vapor nanobubbles improve diffusion in biofilms of antimicrobial agents for wound care

Being responsible for delayed wound healing, the presence of biofilms in infected wounds leads to chronic, and difficult to treat infections. One of the reasons why antimicrobial treatment often fails to cure biofilm infections is the reduced penetration rate of antibiotics through dense biofilms. Strategies that have the ability to somehow interfere with the integrity of biofilms and allowing a better penetration of drugs are highly sought after. A promising new approach is the use of laser-induced vapor nanobubbles (VNB), of which it was recently demonstrated that it can substantially enhance the penetration of antibiotics into biofilms, resulting in a marked improvement of the killing efficiency. In this study, we examined if treatment of biofilms with laser-induced vapor nanobubbles (VNB) can enhance the potency of antimicrobials which are commonly used to treat wound infections, including povidone-iodine, chlorhexidine, benzalkonium chloride, cetrimonium bromide and mupirocin. Our investigations were performed on Pseudomonas aeruginosa and Staphylococcus aureus biofilms, which are often implicated in chronic wound infections. Pre-treatment of biofilms with laser-induced VNB did enhance the killing efficiency of those antimicrobials which experience a diffusion barrier in the biofilms, while this was not the case for those compounds for which there is no diffusion barrier. The magnitude of the enhanced potency was in most cases similar to the enhancement that was obtained when the biofilms were completely disrupted by vortexing and sonication. These results show that laser-induced VNB are indeed a very efficient way to enhance drug penetration deep into biofilms, and pave the way towards clinical translation of this novel approach for treatment of wound infections.

Concomitant Use of Hyaluronic Acid and Laser in Facial Rejuvenation

BACKGROUND

Facial aging is a process that involves many different changes. Therefore, in many patients, it may be necessary to perform a combined treatment. Botulinum toxin A and dermal fillers are the two most popular nonsurgical cosmetic procedures performed globally to treat age-associated changes. However, there are not many studies reporting the concomitant use of dermal fillers and laser technology for facial rejuvenation. This review aims to assess the concomitant use of dermal hyaluronic acid (HA) fillers and laser technology for facial rejuvenation.

METHODS

The present updated consensus recommendations are based on the experience and opinions of the authors and on a literature search.

RESULTS

If a combined procedure (HA and light treatments) is to be performed, on the same day, the panel recommends starting always with the light treatments, avoiding skin manipulations after having injected HA. To customize the therapeutic management, it is crucial to establish a precise diagnosis of the photodamage and loss of volumes suffered by the patients.

CONCLUSIONS

The currently available scientific evidence about the combined use of HA fillers and laser-radiofrequency-intense pulsed light (laser/RF/IPL) is limited and encompasses mainly small and nonrandomized studies. Nevertheless, most of these studies found that, on average, the concomitant use (same day) of laser and HA fillers for facial rejuvenation represents an effective and safe strategy which improves clinical results and patient's satisfaction. Future well-designed clinical studies are needed regarding the effectiveness and safety of combination filler/laser treatments.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Utilizing 808 nm laser for sensitizing of melanoma tumors to megavoltage radiation therapy

Melanotic melanoma has high content of melanin and laser can destroy melanin-containing cells through thermal effect. In this study, the therapeutic effect of 808 nm laser therapy was investigated on B16-F10 melanoma tumor growth and tumor-bearing mice survival time. In addition, as laser can destroy melanin as the main cause of melanoma radioresistance, the effect of laser administration to enhance radiation therapy efficacy at B16-F10 cancer cells was evaluated in vitro and in vivo. Laser therapy (1 W/cm² × 4 min) could cause significant (P < 0.05) inhibition of melanoma tumors' growth (~ 61%) and about three times increase of the tumor-bearing mice survival time in comparison with no-treatment group. In addition, the mice which were treated with 1 W/cm² × 4 min laser administration plus 6 Gy megavoltage radiation therapy exhibited ~ 68% lesser tumors' volume and 27 days increase of survival time in comparison with 6 Gy irradiated tumor-bearing mice. Also, significantly higher (P < 0.05) tumor necrosis percentage was observed at the histopathological slides of 1 W/cm² × 4 min laser + RT treated mice tumors (57 ± 12%) in comparison with radiation therapy group (31 ± 10%). Therefore, not only laser therapy can inhibit melanoma tumors' growth per se but also its combination with radiation therapy can cause a significant enhancement of radiation therapy efficacy. The laser administration can be used as a radiosensitizing method for melanotic melanoma radiation therapy.

Numerical Modeling and Clinical Evaluation of Pulsed Dye Laser and Copper Vapor Laser in Skin Vascular Lesions Treatment

Introduction: Different yellow lasers have been successfully used for the treatment of vascular lesions. This study is aimed to ascertain the role and efficiency of copper vapor lasers (CVLs) and pulsed dye lasers (PDLs) for the treatment of vascular lesions using numerical modeling and to compare results with our clinical experience. In this study we aimed to develop criteria for the choice of more efficient laser exposure mode, investigate more relevant modes of laser irradiation to ensure selective photothermolysis of target vessels, and compare the CVL and PDL efficiency in the course of patients with skin vascular lesions (SVL) treatment. Methods: We performed numerical simulation of the processes of heating a vessel with CVL and PDL to temperatures at which its coagulation could occur. Calculated fluencies were compared with clinical results of laser therapy performed on 1242 patients with skin hemangiomas and vascular malformations (SHVM), including 635 patients treated with CVL and 607 patients treated with PDL. PDL and CVL provided excellent results in 40 and ten days after treatment. The treatment was not painful. Patients did not need anesthesia. Postoperative crusts were greater with PDL than with CVL. Results: Results of computer simulation of a selective vessel heating using PDL and CVL radiation are presented. By results obtained, depth of the location and sizes of vessels that could be selectively heated to more than 75°C are determined. Conclusion: Based on calculated and clinical data, the heating mode for dysplastic vessels using a series of CVL micropulses could be regarded to be safer and more efficient than the mode of a PDL short, powerful pulse.

Laser-induced vapour nanobubbles improve drug diffusion and efficiency in bacterial biofilms

Hindered penetration of antibiotics through biofilms is one of the reasons for the alarming increase in bacterial tolerance to antibiotics. Here, we investigate the potential of laser-induced vapour nanobubbles (VNBs) formed around plasmonic nanoparticles to locally disturb biofilm integrity and improve antibiotics diffusion. Our results show that biofilms of both Gram-negative (Burkholderia multivorans, Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus) bacteria can be loaded with cationic 70-nm gold nanoparticles and that subsequent laser illumination results in VNB formation inside the biofilms. In all types of biofilms tested, VNB formation leads to substantial local biofilm disruption, increasing tobramycin efficacy up to 1-3 orders of magnitude depending on the organism and treatment conditions. Altogether, our results support the potential of laser-induced VNBs as a new approach to disrupt biofilms of a broad range of organisms, resulting in improved antibiotic diffusion and more effective biofilm eradication.

A prospective study of the safety and efficacy of a combined bipolar radiofrequency, intense pulsed light, and infrared diode laser treatment for global facial photoaging

The clinical features of photoaging include: skin texture changes, laxity, rhytides, pigmentary changes, and vascular changes such as erythema and telangiectasias. In order to meet patients' increasing demands for improving all aspects of photoaging at one office visit, employing a multi-modality treatment for all aspects of photoaging has become increasingly desirable for the physician and patient alike. We examine a novel device that employs bipolar radiofrequency (RF), intense pulsed light (IPL), and infrared diode laser. These laser and light source treatments are performed sequentially. This study aims to evaluate the clinical efficacy and safety of this device (i.e., ELOS Triniti™). Twenty-six subjects received four ELOS Triniti™ treatments at 1-month intervals. They were followed up 1, 3, and 6 months after completing the treatments. Two blinded dermatologists used a comprehensive grading scale to evaluate the degree of the photoaging in terms of rhytides, laxity, dyschromia, erythema, telangiectasias, and texture. Subjects used a 0-10 grading scale for self-assessment of photoaging. Additionally, we measured the Erythema Index (EI), Melanin Index (MI), transepidermal water loss scores (TEWL), stratum corneum moisture scores (SC), and dermis moisture scores (D) before treatment and 1, 3, and 6 months after treatment. There was a statistically significant improvement in all five aspects of the comprehensive grading scale. Overall, it had excellent efficacy for improving erythema, telangiectasias, and skin texture. It also had a relatively long effect on improving skin laxity; however, it had only a limited ability to improve rhytides and dyschromia. It can mildly to moderately improve the global photoaging. This global effect can be noted 1 month after treatment and becomes most clinically apparent 3 months after treatment. This is maintained at least 6 months after treatment. MI index and SC and D values increased while EI index and TEWL values decreased after the treatment. The subjects' self-assessment improved by 2.7 ± 1.2 points. The overall satisfaction rate was 88%. The degree of pain measured 2.5 ± 1.9 points on average. There was no downtime and no severe side effects reported. The sequential implementation of bipolar radiofrequency based optical combination devices (IPL, IR, diode laser) is effective and safe for global facial photoaging.

Noninvasive Facial Rejuvenation. Part 3: Physician-Directed-Lasers, Chemical Peels, and Other Noninvasive Modalities

A proper knowledge of noninvasive facial rejuvenation is integral to the practice of a cosmetic surgeon. Noninvasive facial rejuvenation can be divided into patient- versus physician-directed modalities. Patient-directed facial rejuvenation combines the use of facial products such as sunscreen, moisturizers, retinoids, α-hydroxy acids, and various antioxidants to both maintain youthful skin and rejuvenate damaged skin. Physicians may recommend and often prescribe certain products, but patients are in control with this type of facial rejuvenation. On the other hand, physician-directed facial rejuvenation entails modalities that require direct physician involvement, such as neuromodulators, filler injections, laser resurfacing, microdermabrasion, and chemical peels. With the successful integration of each of these modalities, a complete facial regimen can be established and patient satisfaction can be maximized. This article is the last in a three-part series describing noninvasive facial rejuvenation. Here the authors review the mechanism, indications, and possible complications of lasers, chemical peels, and other commonly used noninvasive modalities.