Photobiomodulation CME part II: Clinical applications in dermatology.

Photobiomodulation (PBM) is an emerging treatment modality in dermatology with increasing office and home-based use. PBM is the use of various light sources in the red light (620-700 nm) and near-infrared (700-1440 nm) spectrum as a form of light therapy. PBM is often administered through low-level lasers or light-emitting diodes. Studies show that PBM can be used effectively to treat conditions secondary to cancer therapies, alopecia, ulcers, herpes simplex virus, acne, skin rejuvenation, wounds, and scars. PBM offers patients many benefits compared to other treatments. It is noninvasive, cost-effective, convenient for patients, and offers a favorable safety profile. PBM can be used as an alternative or adjuvant to other treatment modalities including pharmacotherapy. It is important for dermatologists to gain a better clinical understanding of PBM for in-office administration and to counsel patients on proper application for home-use devices to best manage safety and expectations as this technology develops. PBM wavelengths can induce varied biological effects in diverse skin types, races, and ethnicities; therefore, it is also important for dermatologists to properly counsel their skin of color patients who undergo PBM treatments. Future clinical trials are necessary to produce standardized recommendations across conditions and skin types.

A 595 nm pulsed dye laser as an adjuvant intervention for post-comedone extraction erythema and comedone reduction: A randomized, split-face controlled trial.

BACKGROUND: Comedone extraction provides greater satisfaction for acne treatment than conventional treatment alone; however, post-comedone extraction erythema (PCEE) remains a concern for patients. OBJECTIVES: To evaluate the efficacy of pulsed-dye laser (PDL) in PCEE and comedone reduction. METHODS: Mild-to-moderate acne patients were randomly allocated in split-face fashion. Three comedones were extracted on each facial side. On the PDL-treated side, 595-nm PDL was delivered to the entire side with an additional shot on three comedone-extracted sites. Erythema index (EI) and total acne lesion counts (TALC) were evaluated at baseline, week 2 and 4. The comprehensive acne severity scale (CASS) was assessed by three blinded independent pediatric dermatologists. Participant satisfaction surveys were completed at the end of the study. RESULTS: Thirty-five participants (age 12.9-24.2 years) showed no differences in the EI and TALC at baseline on both sides. At weeks 2 and 4, the EI on the PDL-treated side was significantly lower (p < 0.001) with a greater EI reduction (p < 0.001) when compared to the control side regardless of gender and menstruation. There was significantly lower TALC on the PDL-treated side at week 2 (p < 0.001) and week 4 (p = 0.02). No complications were noted with high participant satisfaction reported (median 8; IQR 7-9). PDL remained significantly associated with EI improvements after controlling for gender, menstruation cycle, and examination stress. CONCLUSION: PDL can be an adjunctive intervention for the treatment of PCEE and comedone reduction due to its effectiveness and high participant satisfaction.

Fractional CO2 laser versus 1064-nm long-pulsed Nd:YAG laser for inflammatory acne vulgaris treatment: a randomized clinical trial.

Acne vulgaris is challenging to treat for several individuals. Laser therapy may be a desirable alternative to traditional therapies with limited success. This study aimed to assess efficacy of fractional CO2 laser versus Nd:YAG laser for acne vulgaris therapy. Thirty cases with acne vulgaris underwent both fractional CO2 laser and Nd: YAG laser treatments in a randomized split face design at a 14-day interval for four sessions. The clinical efficacy was evaluated by counting acne lesions and utilizing the Global Acne Severity Scale (GEA Scale). GEAs decreased significantly after both fractional CO2 and Nd:YAG modalities after treatment and at a 3-month follow-up; fractional CO2 demonstrated significant more decrease in GEAs with (P = 0.006, 0.00 (respectively. Moreover, fractional CO2 showed a significantly higher satisfaction level (P = 0.004) and a better clinical improvement percentage regarding inflammatory and noninflammatory acne lesions (P = 0.007 and 0.000, respectively) after 3 months of follow-up. Apart from transient erythema, there were insignificant adverse effects concerning both treated sides. Fractional CO2 and Nd:YAG lasers are efficient physical modalities of acne treatment. However, fractional CO2 laser was more effective and more satisfying to the patients.

Optimal blue light irradiation conditions for the treatment of acne vulgaris in a mouse model.

BACKGROUND: Although blue light is one of the therapeutic approaches used to treat acne vulgaris (AV), there is no consensus on its effectiveness. As a result, it is not recommended in the major acne vulgaris treatment guidelines. OBJECTIVE: The goal of this study was to look into the mechanism, safety, and efficacy of blue light therapy. We achieved this by examining the pathological response, inflammation, and depth of light penetration in a mouse model of cystic AV. METHODS: The aims of the study were addressed by exposing the mice to light with a wavelength of 415 nm under four different irradiation conditions. The exposure was done for five consecutive days followed by a no irradiation period of 72 h. RESULTS: Blue light treatment was most effective when irradiation was performed at 100 mW/cm2 for 20 min for five consecutive days. Inflammatory responses emerged 72 h after the final irradiation dose was administered. These responses were not associated with apoptosis as cleaved caspase-3 staining revealed no significant increases in apoptosis in the skin under any of the tested conditions. Blue light reached the superficial layer of the acne cyst at 5% of the total irradiation power and was attenuated by half for every 50 µm of progress through the cyst. CONCLUSION: In conclusion, blue light could control severe dermatologic inflammatory responses; therefore, it can be used to irradiate AV with high inflammation levels on a daily basis until improvement is observed. In addition, porphyrin, a metabolite of Cutibacterium acnes, and reactive oxygen species generated by the surrounding skin tissue may have essential roles in AV treatment.

Narrow Band Ultraviolet B Versus Red Light-Emitting Diodes in the Treatment of Facial Acne Vulgaris: A Randomized Controlled Trial.

Background: One of the most common dermatological conditions affecting most teenagers is acne. Phototherapy was described as a therapeutic modality with low-side effects of acne vulgaris (AV). Hence, we examined the effects of narrow band ultraviolet B (NBUVB) versus red light-emitting diodes (LEDs) on facial AV. Methods: Forty-five subjects suffering from facial AV mild to a moderate degree were randomly assigned into three groups, 15 subjects within every group. Group A was equipped to NBUVB with 311-313 nm and an initial dose of 250 mJ/cm2, thrice a week for 8 weeks, Group B was equipped red LED with wavelengths 633 ± 6 nm and power density of 80 mW/cm2, thrice a week for 8 weeks, whereas group C had received the only erythromycin as a control group. Outcome measures included measurement of acne lesion count and degree of severity. Measures at three-time intervals were assessed: baseline, 4 weeks (post I), and 8 weeks (post II). Results: Acne numeral findings revealed a significant variance among groups A, B, and C in favor of group A (p < 0.001). Notable improvements were observed across all three groups (p < 0.001). The degree of adjustment effects indicated a greater increase in group A in comparison with group B (p < 0.01), whereas no statistical variance was detected between group B and group C (p > 0.05). Conclusions: Both NBUVB and red LED were effective in acne treatment; NBUVB, however, revealed a highly efficient treatment than red LED in decreasing the acne lesions count and the improved degree of AV severity as measured by the global investigator's assessment scale. Clinical Trial Registration No. NCT04254601.

Effectiveness of CO2 laser therapy in treating acne depressed scar: A protocol of systematic review.

BACKGROUND: This study is to assess the effectiveness of CO2 laser therapy (COLT) in treating patients with acne depressed scar (ADS). METHODS: Relevant randomized controlled trials will be checked by search the electronic databases of Cochrane Library, PUBEMD, EMBASE, Web of Science, Allied and Complementary Medicine Database, VIP Database, CBM database, and China National Knowledge Infrastructure. All potential randomized controlled trials of COLT for patients with ADS will be identified by 2 independent authors by searching all sources from inception to present. Two authors will independently undertake literature selection, data collection and study quality assessment. Any divergences between 2 authors will be settled down by a third author through discussion. RevMan 5.3 software will be used for statistical analysis. RESULTS: This study will assess the effectiveness of COLT for patients with ADS. CONCLUSIONS: This study may provide helpful evidence to determine whether COLT is an effective intervention for patients with ADS. STUDY REGISTRATION: OSF (osf.io/m9ghv).

Visible light. Part I: Properties and cutaneous effects of visible light.

Approximately 50% of the sunlight reaching the Earth's surface is visible light (400-700 nm). Other sources of visible light include lasers, light-emitting diodes, and flash lamps. Photons from visible light are absorbed by photoreceptive chromophores (e.g., melanin, heme, and opsins), altering skin function by activating and imparting energy to chromophores. Additionally, visible light can penetrate the full thickness of the skin and induce pigmentation and erythema. Clinically, lasers and light devices are used to treat skin conditions by utilizing specific wavelengths and treatment parameters. Red and blue light from light-emitting diodes and intense pulsed light have been studied as antimicrobial and anti-inflammatory treatments for acne. Pulsed dye lasers are used to treat vascular lesions in adults and infants. Further research is necessary to determine the functional significance of visible light on skin health without confounding the influence of ultraviolet and infrared wavelengths.

Acne Treatment With Light Absorbing Gold Microparticles and Optical Pulses: An Open-Label European Multi-Centered Study in Moderate to Moderately Severe Acne Vulgaris Patients.

BACKGROUND AND OBJECTIVE: Recently, a novel acne treatment based on selective photothermolysis of pilosebaceous units with follicular delivery of inert gold microparticles as an exogenous chromophore and diode laser pulses has been developed. To evaluate the efficacy and safety of a single monotherapy treatment regimen with gold microparticles and diode laser exposure in patients with moderate and moderately severe acne. Further, to evaluate the added benefit of a second treatment regimen combined with pharmaceutical acne treatment in patients with inadequate initial response. MATERIALS AND METHODS: Patients with moderate and moderately severe facial acne were recruited in this open-label, pilot study. A single treatment regimen consisted of three weekly facial treatments with topically applied gold microparticles and diode laser pulses. Outcome measures were the proportion of patients with ≥40% improvement in number of acne lesions (weighted lesion count [WLC]) at 12 weeks (single treatment regimen, primary outcome measure), 24, and 36 weeks from baseline (two treatment regimens), safety, and patient satisfaction. RESULTS: A total of 28 patients were enrolled in the study (18 males, 10 females, 19 patients with moderate acne severity, 9 with moderately severe, mean age: 19.8 years). Twenty-five patients underwent analysis for outcome measures. After a single monotherapy treatment regimen, 76% patients (19/25) achieved ≥40% reduction in WLC (mean WLC reduction: 63%; SD: 13%). Of the patients undergoing two treatment regimens (n = 9 patients), 56% experienced a reduction in acne lesion burden (WLC) ≥40% at 24 weeks and 89% 36 weeks post-baseline. Mean pain score was 4.0 (SD: 1.3), and transient erythema and perifollicular edema were commonly noted after treatment. Most patients (81%) were either "satisfied" or "very satisfied" with the treatment. CONCLUSION: Acne therapy based on selective photothermolysis with gold microparticles shows promise and may be used in treatment of moderate to moderately severe acne. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Terapia láser de baja potencia en el acné vulgar / Low potency laser therapy in Acne vulgaris

RESUMEN Introducción: el acné es una enfermedad multifactorial que afecta en estructura y función a la unidad pilosebácea. Se presenta en los adolescentes y se padece mundialmente. En los casos más severos, puede involucrar al grupo familiar en su esfera afectiva y económica. La terapia láser de baja potencia se ha empleado como opción de procedimiento médico alternativo para el tratamiento de esta enfermedad; por su acción antibacteriana, antiedematosa y estimulante del sistema inmunitario. Objetivo: determinar el comportamiento del acné vulgar en pacientes con terapia láser de baja potencia. Materiales y métodos: se realizó un estudio descriptivo, prospectivo, en pacientes con formas clínicas leves y moderadas de acné vulgar que acudieron a la consulta de Dermatología del Hospital Universitario Comandante "Faustino Pérez Hernández", provincia Matanzas, entre junio del 2015 a junio del 2016. Se estudiaron las variables: edad, sexo, color de la piel, nivel de escolaridad, clasificación del acné, número de lesiones inflamatorias por hemicara, su tamaño, respuesta al tratamiento y grado de satisfacción. Se procesaron en el paquete estadístico SPSS para Windows, versión 16.0. Resultados: la mayor frecuencia de presentación fue de 18-25 años, sexo femenino y raza blanca. Respuesta satisfactoria independiente a su clasificación, con 15 sesiones, dos veces por semana. Conclusiones: el láser de baja potencia mejora y acorta el tiempo de evolución del acné vulgar (AU).

ABSTRACT Introduction: acne is a multifactor disease that affects the structure and function of the pilosebaceous unit. It is a global condition that starts during adolescence. It can involve the family in its affective and economic sphere in the most severe cases. Low-power laser therapy is used as an alternative medical procedure for the treatment of this disease due to its antibacterial, antiedematous and immune-stimulant action. Objective: to determine the behavior of acne vulgar in patients under low potency laser therapy. Materials and methods: a descriptive, prospective study was carried out in patients suffering mild and moderated clinical forms of acne vulgaris who assisted the Dermatology consultation of the University Clinico-surgical Hospital "Faustino Perez Hernandez"¨, Matanzas province, from June 2015 to June 2016. The studied variables were age, sex, race, scholarship, acne classification, number of inflammatory lesions per hemiface, lesson size, answer to treatment and satisfaction level. Data were processed with the SPSS statistical package, 16.0 version for Windows. Results: the highest presentation frequency was in people aged 18-25 years, of the female sex and white race. The answer was satisfactory independently to classification with 15 sessions, twice a week. Conclusion: low potency laser improves and reduces acne vulgaris evolution time (AU).

Terapia láser de baja potencia en el acné vulgar / Low potency laser therapy in Acne vulgaris

RESUMEN Introducción: el acné es una enfermedad multifactorial que afecta en estructura y función a la unidad pilosebácea. Se presenta en los adolescentes y se padece mundialmente. En los casos más severos, puede involucrar al grupo familiar en su esfera afectiva y económica. La terapia láser de baja potencia se ha empleado como opción de procedimiento médico alternativo para el tratamiento de esta enfermedad; por su acción antibacteriana, antiedematosa y estimulante del sistema inmunitario. Objetivo: determinar el comportamiento del acné vulgar en pacientes con terapia láser de baja potencia. Materiales y métodos: se realizó un estudio descriptivo, prospectivo, en pacientes con formas clínicas leves y moderadas de acné vulgar que acudieron a la consulta de Dermatología del Hospital Universitario Comandante "Faustino Pérez Hernández", provincia Matanzas, entre junio del 2015 a junio del 2016. Se estudiaron las variables: edad, sexo, color de la piel, nivel de escolaridad, clasificación del acné, número de lesiones inflamatorias por hemicara, su tamaño, respuesta al tratamiento y grado de satisfacción. Se procesaron en el paquete estadístico SPSS para Windows, versión 16.0. Resultados: la mayor frecuencia de presentación fue de 18-25 años, sexo femenino y raza blanca. Respuesta satisfactoria independiente a su clasificación, con 15 sesiones, dos veces por semana. Conclusiones: el láser de baja potencia mejora y acorta el tiempo de evolución del acné vulgar.

ABSTRACT Introduction: acne is a multifactor disease that affects the structure and function of the pilosebaceous unit. It is a global condition that starts during adolescence. It can involve the family in its affective and economic sphere in the most severe cases. Low-power laser therapy is used as an alternative medical procedure for the treatment of this disease due to its antibacterial, antiedematous and immune-stimulant action. Objective: to determine the behavior of acne vulgar in patients under low potency laser therapy. Materials and methods: a descriptive, prospective study was carried out in patients suffering mild and moderated clinical forms of acne vulgaris who assisted the Dermatology consultation of the University Clinico-surgical Hospital "Faustino Perez Hernandez"¨, Matanzas province, from June 2015 to June 2016. The studied variables were age, sex, race, scholarship, acne classification, number of inflammatory lesions per hemiface, lesson size, answer to treatment and satisfaction level. Data were processed with the SPSS statistical package, 16.0 version for Windows. Results: the highest presentation frequency was in people aged 18-25 years, of the female sex and white race. The answer was satisfactory independently to classification with 15 sessions, twice a week. Conclusion: low potency laser improves and reduces acne vulgaris evolution time.

Propionibacterium acnes susceptibility to low-level 449 nm blue light photobiomodulation.

BACKGROUND AND OBJECTIVE: Recent advances in low-level light devices have opened new treatment options for mild to moderate acne patients. Light therapies have been used to treat a variety of skin conditions over the years but were typically only available as treatments provided by professional clinicians. Clinical application of blue light has proven to be effective for a broader spectral range and at lower fluences than previously utilized. Herein, we tested the hypothesis that sub-milliwatt/cm2 levels of long-wave blue light (449 nm) effectively kills Propionibacterium acnes, a causative agent of acne vulgaris, in vitro. MATERIALS AND METHODS: Two types of LED light boards were designed to facilitate in vitro blue light irradiation to either six-well plates containing fluid culture or a petri plate containing solid medium. P. acnes. Survival was determined by counting colony forming units (CFU) following irradiation. P. acnes was exposed in the presence and absence of oxygen. Coproporphyrin III (CPIII) photoexcitation was spectrophotometrically evaluated at 415 and 440 nm to compare the relative photochemical activities of these wavelengths. RESULTS: 422 and 449 nm blue light killed P. acnes in planktonic culture. Irradiation with 449 nm light also effectively killed P. acnes on a solid agar surface. Variation of time or intensity of light exposure resulted in a fluence-dependent improvement of antimicrobial activity. The presence of oxygen was necessary for killing of P. acnes with 449 nm light. CPIII displayed clear photoexcitation at both 415 and 440 nm, indicating that both wavelengths are capable of initiating CPIII photoexcitation at low incident light intensities (50 uW/cm2 ). CONCLUSION: Herein we demonstrate that sub-milliwatt/cm2 levels of long-wave blue light (449 nm) effectively kill P. acnes. The methods and results presented allow for deeper exploration and design of light therapy treatments. Results from these studies are expanding our understanding of the mode of action and functionality of blue light, allowing for improved options for acne patients. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

A Novel Combined Light-Based Treatment of Acne Vulgaris With 1,450-nm Diode Laser and 450-nm Blue Light.

BACKGROUND: Nonablative 1,450-nm diode laser (DL) and visible blue light (BL) have been effectively used for acne with superior safety profiles. OBJECTIVE: To evaluate synergistic effects of sequential DL and BL application for acne. METHODS: A 20-week, randomized split-face study was conducted to compare clinical courses between 2 facial sides either receiving sequential application of DL and BL or BL alone in 24 patients with mild to moderate facial acne vulgaris. Patients were scheduled to receive 3 consecutive sessions at 4-week intervals. Objective assessments, including revised Leeds grades, lesion counts, and sebum output measurements, and patients' subjective satisfaction were investigated. RESULTS: Both combination and BL sides demonstrated steady improvement of inflammatory acne lesions with 62.3% and 35.2% decreases at the 12-week follow-up visit compared with baseline respectively. For noninflammatory lesions and seborrhea, only combination regimen demonstrated improvement. Patients' subjective assessments paralleled objective findings. For safety profiles, no severe adverse effect was observed on both sides, and mild symptoms resolved spontaneously within a day. CONCLUSION: The combination regimen demonstrated synergistic efficacies for acne and seborrhea, with satisfactory safety profiles. Therefore, a few sessions of these light-based applications would be a viable option for acne treatments.

Integrated Cooling-Vacuum-Assisted Non-Fractional 1540-nm Erbium:Glass Laser: A New Modality for the Simultaneous Effective Treatment of Acne Lesions and Scars

Introduction: Acne vulgaris is a common skin disorder with a significant impact on patients' quality of life. There is currently no treatment designated to treat acne lesions and scars concurrently. However, mid-infrared lasers may promote neocollagenesis within atrophic scars, while exerting a beneficial effect on acne lesions. Objectives: To determine the safety and efficacy of an integrated cooling-vacuum-assisted non-fractional 1540-nm Erbium:Glass laser for the treatment of acne lesions and scars. Patients and Methods: Twenty-two patients (8 male, 14 female) with mild-to-moderate acne and moderate-to-severe acne scars were included. Patients were treated using a non-fractional 1540-nm Er:Glass laser (Harmony XL™, Alma Lasers Ltd.). Acne lesions and scars were exposed to 3-4 stacked pulses emitted at a rate of 3Hz for up to two passes per treatment session (spot size, 4 mm; fluence, 400-600 mJ/pulse), receiving overall 3-7 treatments with 2-3-week intervals. Patients were followed-up one and three months following their last treatment. Clinical evaluation including (i) overall aesthetic appearance, (ii) acne lesions, and (iii) acne scars, assessed independently by two dermatologists and graded on a scale of 0 (exacerbation) to 4 (76-100 percent improvement); and (iv) pain perception, adverse effects and patients' satisfaction. Results: All but one patient completed treatment and follow-up and had moderate-to-significant improvement in all outcomes (overall aesthetic appearance, mean 3.9 [1 month] and 3.75 [3 month] improvement; acne lesions, 3.5 [1 month] and 2.3 [3 month] improvement; scarring 4 [1 month] and 4.2 [3 month] improvement). Pain and adverse effects were mild and transient. Patients' mean satisfaction was 4.2. Conclusion: Cooling-vacuum-assisted 1540 nm laser is a safe and effective modality for the simultaneous treatment of acne lesions and scars.

Low-dose blue light irradiation enhances the antimicrobial activities of curcumin against Propionibacterium acnes.

Propionibacterium acnes (P. acnes) is an opportunistic infection in human skin that causes acne vulgaris. Antibiotic agents provide the effective eradication of microbes until the development of drug-resistant microbes. Photodynamic inactivation (PDI) is a non-antibiotic therapy for microbial eradication. In this study, the visible blue light (BL, λmax = 462 nm) was used to enhance the antimicrobial activities of curcumin, a natural phenolic compound. Individual exposure to curcumin or BL irradiation does not generate cytotoxicity on P. acnes. The viability of P. acnes was decreased significantly in 0.09 J/cm2 BL with 1.52 µM of curcumin. Furthermore, the low-dose blue light irradiation triggers a series of cytotoxic actions of curcumin on P. acnes. The lethal factors of photolytic curcumin were investigated based on the morphology of P. acnes by SEM and fluorescent images. The membrane disruption of microbes was observed on the PDI against P. acnes. Chromatography and mass spectrometry techniques were also used to identify the photolytic metabolites. Curcumin could be photolysed into vanillin through BL irradiation, which presents a strong linear relationship in quantitation. Because the safety of blue light in mammalian cell has been proven, the photolytic curcumin treatment could support non-antibiotic therapy to eradicate P. acnes on clinical dermatology.

Lasers, Light, and the Treatment of Acne: A Comprehensive Review of the Literature.

INTRODUCTION: Acne vulgaris is common dermatologic condition with an estimated prevalence of 70 to 87%. Acne has been shown to have a significant impact on patient quality of life and mental health, especially as inflammatory lesions typically occur on cosmetically sensitive areas with the potential for permanent scarring. There have been numerous advances in the treatment of inflammatory acne with light-based and laser devices. OBJECTIVE: To review the current evidence for light-based and laser treatments in the management of inflammatory acne. METHODS: An analysis was conducted of PubMed indexed English language literature regarding management of inflammatory acne using light-based and laser treatments. RESULTS: Evidence for the utilization of laser and light-based therapy for acne was summarized in a comprehensive review. Laser and light-based treatment holds the advantages of improved patient compliance and safety profiles in comparison to pharmacologic therapy. Efficacy of device based treatment varied in comparison to standard topical treatment regimens, often more effective when used in combination therapy. Adverse effects reported were generally self-limited. DISCUSSION: These treatments do and will continue to play an important and enlarging role in the management of acne. Larger scale studies with standardization of treatment protocols are warranted.

J Drugs Dermatol. 2017;16(11):1095-1102.

Fractional carbon dioxide (CO2) laser combined with topical tretinoin for the treatment of different forms of cystic acne.

Nodulocystic acne is prone to scarring and difficult to treat with treatments other than oral isotretinoin. The aim of this article is to discuss the role of a single session of a fractional carbon dioxide (CO2) laser combined with a topical treatment with a tretinoin and antibiotic gel for a month as a successful treatment to improve nodulocystic acne and chronic microcystic acne. Two cases were involved: the first with nodulocystic acne lesions that persisted after oral retinoids and the second with chronic microcystic acne resistant to topical treatments. After only one session of treatment with the CO2 laser and the topical treatment, a complete healing of the nodulocystic acne lesions was observed with minimal secondary effects. The microcystic acne showed great improvement. No other topical or oral treatment was needed. This treatment could be a safe and effective treatment for nodulocystic acne lesions and microcystic acne when other treatments fail. More studies should be performed to confirm our results.

Randomized, controlled trial split-faced study of 595-nm pulsed dye laser in the treatment of acne vulgaris and acne erythema in adolescents and early adulthood.

The high prevalence of acne vulgaris in teenagers has increased comorbidities. Lasers offer alternative options for acne treatment because they have rapid action, low systemic adverse effects, and do not require everyday treatment. To study the efficacy and patients' satisfaction of 595-nm pulse dye laser (PDL) treatment of acne vulgaris and acne erythema in adolescents and early adulthood, we designed a blocked-randomized, split-faced 595-nm PDL (fluence 8 J/cm3 pulse duration 10 ms, spot size 7 mm, 2 session every 2 weeks) study in patients with mild to moderate acne by comparing the laser-treated and non-treated side. The acne lesion counts, acne erythema grading, and acne severity grading were evaluated at baseline and 2, 4, and 8 weeks. Thirty patients were recruited. The results showed no statistically significant difference except the papule count at week 4 which was -1.828 on the treated side and 0.103 on the non-treated side of the face, P-value 0.0018. There was no statistically significant difference of acne severity grading and acne erythema grading between both sides of the face. The mean scores of patients' satisfaction on the laser-treated side were 75, 81, and 81%, respectively. The PDL treatment in this study reveals no significant improvement in acne therapy; however, the patients were satisfied with this laser treatment.

Delivery of light to the skin through ablated conduits.

BACKGROUND AND OBJECTIVES: Non-invasive laser skin treatment modalities are generally designed to protect the epidermis by cooling and limiting the laser energy deposition in accordance with skin type. We explore a treatment modality that uses a 2,940 nm Er:YAG laser with high tissue absorption to ablate an array of channels through the epidermis and upper dermis, and then deliver laser energy from a 1,320 nm Nd:YAG laser with lower tissue absorption through the ablated channels. Treatment through ablated conduits offers a unique capability to deliver laser radiation to a deeper level in the dermis or beyond the dermis and the delivered energy to be deposited in a nearly uniform distribution. The ablated channels represent a relatively small surface and volume fraction of the epidermis and upper dermis, and heal very fast. A pilot study was performed to explore the benefits of treatments through ablated conduits for skin tightening, cellulite, and acne scarring. MATERIALS AND METHODS: A custom-built laser from Cynosure Inc. was designed to deliver to the epidermis up to 3 J/cm2 at 2,940 nm from an Er:YAG laser followed in less than 10 ms by up to 20 J/cm2 at 1,320 nm from a Nd:YAG laser. Both laser sources were delivered to the skin through a diffractive lens array. The spatial intensity modulation created by the diffractive lens array on the skin surface consisted of a low energy density background that did not damage the epidermis and a superimposed array of much higher energy density regions where the Er:YAG laser ablated the channels, and most of the 1,320 nm laser energy was delivered through the channels. Various fluence combinations of the ablative and non-ablative lasers were tested on ex vivo human skin samples to evaluate tissue effects and parameters for a clinical test. A limited clinical study was performed to evaluate tissue response and healing effects. RESULTS: Histology confirmed the presence of ablative channels through the epidermis and upper dermis as well as the absence of epidermal damage apart from the channels. Three days posttreatment there was complete skin healing with no evidence of channel ablation or coagulation in the skin biopsies. Limited clinical testing for facial treatments showed mild improvement for acne scarring and skin laxity. CONCLUSIONS: Laser skin treatment through ablated conduits can be performed safely with fast subsequent healing of the channels ablated through the skin. Further refinement of the treatment parameters and variation of the wavelength of the non-ablative laser source may bring improved treatment efficacy. Lasers Surg. Med. 49:69-77, 2017. © 2016 Wiley Periodicals, Inc.

Fractional resurfacing in the Asian patient: Current state of the art.

BACKGROUND AND OBJECTIVE: Fractionated photothermolysis (FP) has revolutionized modern laser technology. By creating selective columns of microthermal damage, fractionated devices allows for greater treatment depths to be achieved without the prolonged downtime and risk of complications seen in traditional fully ablative laser resurfacing. Fractional resurfacing is a proven method to treat a variety of cutaneous conditions. In the Caucasian patient, a wide range of devices and treatment settings can be utilized safely and effectively. However, ethnic skin requires special consideration due to its unique pigmentary characteristics and clinical presentations. In this review article, we detail the current indications and strategies to optimize results and mitigate complications when utilizing fractional resurfacing for the Asian patient. METHODS: A review of the MEDLINE English literature was conducted on fractionated laser devices studied in the Asian population. Articles included describe non-ablative devices including fractionated erbium glass, thulium fiber, diode, and radiofrequency devices; and ablative devices including fractionated carbon dioxide (CO2 ) laser, erbium yttrium aluminum garnet and yttrium scandium gallium garnet (YSGG) laser. These data were integrated with the expert opinion of the authors. CONCLUSION: Taking into account the unique characteristics and cosmetic concerns of the Asian population, fractional resurfacing can be considered a safe and effective option for the treatment of atrophic and hypertrophic scarring, and photorejuvenation in ethnic skin types. Select cases of melasma may be treated with fractionated non-ablative devices, but utilized with caution. The predominant complication associated with fractional resurfacing for these conditions is post-inflammatory hyperpigmentation (PIH) and rebound worsening of melasma. A greater number of treatments at lower density settings and wider treatment intervals typically produce the lowest risks of PIH without compromising treatment efficacy. Lasers Surg. Med. 49:45-59, 2017. © 2016 Wiley Periodicals, Inc.