Ablative Fractional Versus Nonablative Fractional Lasers—Where Are We and How Do We Compare Differing Products?

Prophylactic Antibiotics Are Unnecessary for Routine CO2 Laser Burn Scar Treatment

CO2 ablative fractional laser (CO2 AFL) therapy is a safe and effective procedure when used in the treatment of hypertrophic scars for burn patients. It has a high patient satisfaction rate and a minimal side effect profile, typically consisting of postoperative pain, irritation, surgical site inflammation, and, in rare cases, infection. Although prophylactic antibiotics have historically been recommended, there is a paucity of literature on the topic and recent studies indicate that they may be unnecessary in routine cases. In this retrospective, single-center descriptive study, 230 cases in patients with hypertrophic burn scars treated with CO2 AFL therapy were compared. 28 cases were with the use of prophylactic antibiotics and 201 cases were without the use of prophylactic antibiotics. We found that there was no significant association between the use of antibiotics and the prevention of topical skin infection in cases treated with CO2 AFL therapy (P = 1). Therefore, we conclude that the omission of prophylactic antibiotics is not associated with an increased risk of infection and recommend that prophylactic antibiotics should not be indicated in the setting of routine CO2 AFL therapy for patients with hypertrophic burn scars.

Large area fractional laser treatment of mouse skin increases energy expenditure

Fractional laser (FL) treatment is a common dermatologic procedure that generates arrays of microscopic treatment zones separated by intact tissue, promoting fast wound healing. Using a mouse model, we introduced a large area fractional laser treatment (LAFLT) method to study metabolic effects. Using two laser modalities, ablative FL (AFL) and non-ablative FL (NAFL), and exposing different percentages of mice's total body surface area (TBSA), we followed changes in metabolic parameters in real time using metabolic cages. Additionally, body composition, markers of inflammation, neurohormonal signaling, and browning of adipocytes were investigated. LAFLT, especially in high TBSA groups, had specific metabolic effects such as significantly increased average daily energy expenditure, increased fat mass loss, systemic browning of adipocytes, and inflammatory states, without compromising other organs. The ability of LAFLT to stimulate metabolism in a controlled way could develop into a promising therapeutic treatment to induce positive metabolic changes that replace or augment systemic drugs.

Fractional ablative laser therapy for the treatment of severe burn scars: A pilot study of the underlying mechanisms

Ablative fractional resurfacing is clinically an efficient treatment for burn scar management. The aim of this pilot study was to investigate the poorly understood mechanisms underlying ablative fractional CO2 laser (AFL-CO2) therapy in relation to biomarkers S100 and 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1). S100 stains for Langerhans cells and neuronal cells, potentially representing the pruritus experienced. 11β-HSD1 catalyses the interconversion of cortisol and cortisone in cells, promoting tissue remodelling. Immunohistochemical analysis of S100 and 11β-HSD1 protein expression in the dermis and epidermis of the skin was performed on normal skin, before and after AFL-CO2 therapy. Data assessing outcome parameters was collected concurrently with the skin biopsies. 13 patients were treated with AFL-CO2 therapy. Langerhans cells decreased by 39% after 2nd treatment. Neuronal cells were overexpressed before treatment in the scar tissue by 91% but levels returned to that resembling normal skin. 11β-HSD1 expression in keratinocytes was significantly higher after laser treatment compared to before in scar tissue (p <0.01). No clear correlation was found in dermal fibroblast numbers throughout the treatment course. Whilst the role of the explored mechanisms and their association with clinical outcomes cannot conclusively be stated, this pilot study demonstrates promising trends that encourages investigation into this relationship.

Striae Distensae: Scars without Wounds

SUMMARY

Striae distensae, or stretch marks, are common linear lesions of atrophic skin characterized histologically by epidermal atrophy, absent rete ridges, and alterations in connective tissue architecture. Hormonal excess, mechanical stress, and genetic predisposition are all associated with striae distensae, but their exact pathogenesis remains unknown. Despite a multitude of options, no single treatment has yet proven effective. In this article, the authors describe an up-to-date overview of striae distensae in terms of their etiology, pathophysiology, and therapeutic options. Further research is required to better elucidate their pathophysiology and to develop targeted effective treatments.

Saline in Dermatology: A literature review

BACKGROUND

Saline, with its different concentrations, is the most used crystalloid solution in medicine. In dermatology, no large studies investigated the benefits of saline. The aim of this article is to review the different possible uses of saline in dermatology, in order to give final recommendations based on the literature review and our experience.

METHODS

We performed a literature search based on PubMed, EMBASE, WHO Global Health Library, Virtual Health Library, Web of Science, Scopus, Google Scholar, and Research gate. using the keywords: saline, physiological, hypertonic, isotonic, hypotonic, salt solution, sodium chloride, 0.9% NaCl, solvent, drug delivery, injection mixtures, diluent, sclerosant, intravenous, intralesional, injection, topical, soaks, fomentation, inhalation, alopecia, psoriasis, scars, atopic dermatitis, eczema, bromoderma, iododerma, lipodystrophy, in various combinations with the Boolean operators AND, OR and NOT. We also hand-searched textbooks.

RESULTS

Saline was used as a diluent with intralesional injection of steroids to minimize the risk of steroid-induced atrophy, being safe and free from preservatives that may precipitate steroids at site of injection and maximize their side effects. Saline has also been used after surgery, when atrophic scars take place or anticipated, and through injection in leishmaniasis, granuloma annulare, atrophic acne scars before using other expensive and less tolerated treatment options.

CONCLUSIONS

The saline represents a helpful option as a diluent with intralesional injection of steroids in various dermatologic therapeutic indications. Moreover, the use of saline in this setting could help to minimize the risk of steroid-induced atrophy. We encourage the use of saline after surgery, when atrophic scars take place or anticipated. Also, we encourage a trial of saline injection in leishmaniasis, granuloma annulare, atrophic acne scars before using other expensive and less tolerated treatment options.

A Prospective Study Evaluating the Use of Helium Plasma for Dermal Resurfacing

BACKGROUND AND OBJECTIVES

A novel helium plasma device was evaluated for efficacy and safety for dermal resurfacing (ClinicalTrials.gov Identifier: NCT03286283). The helium plasma device delivers energy in a controlled, bimodal fashion that when compared with the nitrogen plasma predicate device in a porcine animal model demonstrated a more limited depth of thermal effect but a greater skin tissue contraction.

STUDY DESIGN/MATERIALS AND METHODS

Fifty-five eligible subjects seeking improvement in facial rhytids were enrolled for study at one of three investigational sites. Most subjects underwent full-face treatment. Power levels were limited to 20% at peri-oral and peri-orbital areas-a level that correlates to an energy density 40% lower than the highest setting on the predicate device. Three-month post-treatment Fitzpatrick Wrinkle and Elastosis Scale (FWS) scores were compared with baseline scores as determined by blinded independent photographic reviewers (IPRs) and study investigators.

RESULTS

Blinded IPRs observed a ≥1-point FWS improvement in 63.64% of subjects whereas study investigators noted a ≥1-point FWS improvement in 54 of 55 subjects (98.18%) of subjects. 90.9% of subjects indicated "improvement" in appearance utilizing the modified Global Aesthetic Improvement Scale. Subgroup analysis showed 1-point (±0.05) FWS improvement by IPRs and study investigators for Fitzpatrick Skin Types II and III, age≥62, two of three study sites, and post-treatment oral steroid use. Eighty Non-Serious Adverse Events in 39 subjects were reported, most of which resolved within 14 days or less. There were no Serious Adverse Events or Unanticipated Device Effects reported.

CONCLUSION

At the modest power level studied, a significant improvement from a single pass helium plasma dermal resurfacing treatment was observable in most subjects by IPRs and investigators, and no serious adverse events were reported. The discrepancy between IPR and study investigator FWS improvement may be explained in part by the limitations of assessing two-dimensional photographs versus live in-person evaluation of subjects. Studies evaluating higher energy levels and/or multiple treatment passes are ongoing. Lasers Surg. Med. © 2020 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals, Inc.

Application of reflectance confocal microscopy to investigate the non-ablative, micro-ablative, and ablative effects of CO2 fractional laser irradiation on skin

CO₂ fractional laser, as an ablative fractional laser, is commonly used in cosmetic treatment. We applied CO₂ fractional laser irradiation to skin in vitro and used reflectance confocal microscopy (RCM) to image and detect the presence of any non-ablative, micro-ablative and ablative effects, in order to better understand the features of a CO₂ fractional laser. In vitro irradiation of foreskin was performed using a CO₂ fractional laser. Foreskin specimens were divided into 4 groups that received different amounts of irradiation energy, based on the number of irradiation passes they received: 5, 10, 15, and 20 passes, respectively. This corresponds to fluence energy of 16.3, 32.6, 48.9, 65.3 J/cm². Immediately after irradiation, digital microscopy (DM), RCM, and histopathology were performed to observe whether the non-ablative, micro-ablative, and ablative phenomenon occurred, and the injury features of MTZs. Immediately after CO₂ fractional laser irradiation, RCM and DM showed that when the numbers of passes were 5 and 10, a micro-ablative column (MAC) could not be observed or was very small. We mainly observed a thicker thermal coagulation zone (TCZ), representing non-ablative or micro-ablative effects. When the number of passes were increased to 15 and 20, the MAC was significantly enlarged and surrounded by a TCZ of medium thickness, representing ablative effects. For the first time, this study used RCM and DM to demonstrate that a CO₂ fractional laser could achieve non-ablative, micro-ablative, and ablative effects on irradiated skin via different energy levels.

Dual-plane hyaluronic acid treatment for atrophic acne scars

BACKGROUND

Acne is a common condition that affects up to 80% of all adolescents. Scarring may affect some 95% as a function of severity and delay before treatment. The pathogenesis includes enzymatic degradation of collagen fibers and subcutaneous fat.

OBJECTIVE

This study aimed to treat atrophic acne scars using the Dual-Plane injection of Hyaluronic Acid.

METHODS

A total of 12 patients with moderate-to-severe atrophic acne scars were treated with a novel NAHYCO™ based Hyaluronic Acid filler, using a dual-plane technique for two treatment sessions at a 4-week interval. Results were objectively assessed by two blinded Dermatologists and subjectively evaluated by the patients themselves.

RESULTS

A total of 8 out of the 12 patients reported moderate improvement, two indicated marked improvement and two rated minimal improvement. Dermatologists' mean global evaluation score was 2.5 ± 0.43.

LIMITATIONS

The small sample size and regional nature of a single-center study. Nevertheless, both the expert dermatologists' and the patients' evaluations of standardized high-resolution medical photographs were consistent, suggesting that this inherent bias was negligible.

CONCLUSION

The treatment led to impressive improvement in the depth of the scars, suggesting that this technique can result in safe and rapid amelioration of atrophic acne scars in only two sessions.