Hypertrophic Burn Scars Research Articles

Efficacy of Cybele Scagel Phonophoresis on Post-Burn Hypertrophic Scar

Background: Hypertrophic scar (HTS) formation after burn remains a major issue for burned patients and is considered a huge problem for clinicians because the hypertrophic scar is painful, reddish, elevated, pruritic, and aesthetically unacceptable. Objective: To evaluate the therapeutic efficacy of Cybele Scagel phonophoresis on the treatment of hypertrophic scar post burn cases. Patients and methods: Thirty patients who had hypertrophic scar after wound closure with ages ranged from 20 to 45 years were selected randomly and divided into two equal groups in number (15 patients each). Group A (study group): received Cybele scagel phonophoresis, 3 sessions per week for 8 weeks (24 sessions), while patients in group B (control group): received topical cybele scagel for 8 weeks. Methods of assessment before and after the study included Modified Vancouver scar scale (VSS) to assess hypertrophic scar characteristics (height, vascularity, pigmentation and pliability) and digital imaging for visual assessment of the scars. Results: the results of the study showed that between groups comparison, there was no significant difference in VSS between both groups pre-treatment (p > 0.05). Comparison between group A and group B post-treatment revealed a significant decrease in VSS of the group A compared to that of group B (p > 0.05). Conclusion: It could be concluded that Cybele Scagel phonophoresis is an effective and safe modality that can be used for improving appearance of post burn hypertrophic scar.

The Effectiveness of Laser Therapy for Hypertrophic Burn Scars in Pediatric Patients: A Prospective Investigation

Abstract Laser therapy has become a valuable treatment option for hypertrophic burn scars. Improvements in scar symptoms have been achieved using the ablative fractional carbon dioxide laser as well as the pulsed dye laser. However, research regarding the use of laser therapy among pediatric patients remains limited. Thus, the aim of this study was to investigate the effectiveness of using laser therapy to improve hypertrophic burn scars in a pediatric population using a comprehensive scar assessment protocol. A pragmatic, single-center, prospective observational study was conducted at a tertiary pediatric hospital. Twenty participants with hypertrophic burn scars were included. Laser procedures were administered at approximately two month intervals and scars were evaluated at five time points over one year using the Vancouver Scar Scale, the Patient and Observer Scar Assessment Scale, conventional ultrasound, ultrasound elastography, and a multi-probe skin analysis device. Seventy-one laser procedures were performed with most participants receiving treatment with both the ablative fractional carbon dioxide laser and the pulsed dye laser at the same session (83%). From baseline to study completion, significant improvements in all scar measures were observed (p < .05). In particular, improvements in overall scarring and in specific scar properties including thickness, stiffness, and color were found (p < .05). To the best our knowledge, this is the most comprehensive study to date to evaluate the effect of laser treatment on hypertrophic burn scars in a pediatric population. Our findings suggest that laser therapy is a beneficial treatment for burn-injured children as evidenced by the improvements in subjective and objective scar assessment measures.

Early intervention by Z-plasty combined with fractional CO2 laser therapy as a potential treatment for hypertrophic burn scars

The aim of this study is to determine whether Z-plasty combined with fractional CO2 laser therapy can be a potential management option for hypertrophic burn scars in the proliferation stage. A total of 105 patients (46 male and 59 female patients) diagnosed with hypertrophic scars under tension but without any functional limitations were enrolled in this study. The Vancouver Scar Scale (VSS) score and scar height were analyzed and compared. The VSS scores for all scars were improved in all groups after treatment. The scar height was also significantly decreased in each group after treatment (P < 0.05). In the C group, the scar height decreased significantly to 2.62 ± 0.21 mm, which was the maximum extent at the ≦ 6 month time point compared to the decrease in the other groups. Compared to the > 12 month time point for the C group, there was a significant difference between the ≦ 6 month time point for the L group and the > 12 month time point for the Z group. The proportion of satisfied patients was highest at 89.47% at the ≦6 month time point in the C group and lowest at 65.52% at the > 12 month time point in the L group. Six representative cases are presented. Z-plasty can decrease the thickness of a hypertrophic burn scar, which not only reduces the scar tension but also makes it easy to treat the scar with a fractional CO2 laser. Subsequent treatment with a fractional CO2 laser can better improve the color and texture of the scar.

37 Analysis of the Utility of CO2 and Pulse-Dye Lasers in the Treatment of Hypertrophic Burn Scars

Abstract Introduction Despite advances in burn care, hypertrophic burn scars (HTBS) remain a significant source of morbidity. Treatment often involves use of CO2 lasers to reduce thickness and pulse-dye lasers (PDL) to reduce erythema. Despite frequent utilization, little quantitative data exists. This study seeks to objectively determine the effects of these laser treatments on burn scars. Methods Patients found to have HTBS undergoing laser treatments were approached for enrollment. Following enrollment, an area of HTBS outside of the treatment area was divided into 4 equal 3x3cm squares which were randomized to receive either CO2, PDL, CO2+PDL, or no treatment. Patients underwent a total of 3 treatments, 4–6 weeks apart, and were seen for follow-up over 3–6 months. Scar assessments occurred at each visit prior to treatment and consisted of digital photographs, ultrasound assessment for scar thickness, colorimetry, and the Patient and Observer Scar Assessment Score (POSAS). Results Twenty-five patients were enrolled at our institution. To date, 12 (48%) have completed all 3 treatments and the remainder are still in their follow-up period. Median initial scar thickness (ST) was 0.3cm. Mean time since injury was 9 months. Overall, there was a significant decrease in ST over time (p=0.0246) but not between treatment groups. There were no significant changes seen in melanin, erythema, or POSAS scores (p=0.9030, 0.6470, and 0.1495, respectively). When separated by ST before initiation of treatment, thin scars (&amp;lt; 3cm) appeared to be overall less erythematous in groups treated with PDL and CO2+PDL and untreated groups (p=0.0358, 0.0027. 0.0118, respectively) as compared to thick scars (≥3cm). Thin scars treated with PDL and CO2+PDL were also less pigmented than thick scars (p=0.0127, 0.0213, respectively). Erythema significantly decreased between the last treatment and the final visit for PDL and CO2+PDL groups (p&amp;lt; 0.0001). Older scars (≥9 months prior to treatment) tended to have a greater reduction in thickness as compared to newer scars but the difference was not significant to date. Conclusions Laser therapy is often employed in the treatment of HTBS. However, few studies have determined their objective benefits. Based on a preliminary analysis of our data, we have shown an overall decrease in scar thickness, less pigmentation, and less erythema in thin scars treated with PDL or CO2+PDL. Further analysis will be performed after additional follow-up information is collected.

29 The Effectiveness of Laser Therapy for Hypertrophic Burn Scars in Pediatric Patients: A Prospective Investigation

Abstract Introduction Laser therapy has emerged as a valuable treatment option for hypertrophic burn scars over the past decade. Improvements in scar symptoms have been found using the ablative fractional carbon dioxide laser (AFCL) as well as the pulsed dye laser (PDL). However, research regarding the use of laser therapy among pediatric burn patients remains limited. Thus, the aim of this study was to investigate the effectiveness of using laser therapy to improve hypertrophic burn scars in a pediatric population using a comprehensive set of subjective and objective scar assessment tools. Methods A single-center, prospective observational study was carried out at a tertiary pediatric hospital. Twenty participants with hypertrophic burn scars that had not received previous laser treatment were included. Laser procedures were administered at approximately two-month intervals and each participant attended five study visits over the course of one year. A comprehensive set of scar assessment tools including the Vancouver Scar Scale, the Patient and Observer Scar Assessment Scale, conventional ultrasound, ultrasound elastography, and a multi-parameter skin analysis device were used to evaluate scar properties at each study visit. Results Seventy-one laser procedures were carried out with most participants receiving treatment with both the AFCL and the PDL at the same session (83%). All participants underwent at least three laser procedures with no complications noted. From baseline to study completion, statistically significant improvements in all scar measures, both subjective and objective, were observed (p &amp;lt; 0.05). More specifically, improvements in overall scarring and in specific scar properties including thickness (p &amp;lt; 0.05), stiffness (p &amp;lt; 0.05), and color (p &amp;lt; 0.05) were found. Conclusions To our knowledge, this is the most comprehensive study to date to evaluate the effect of laser treatment on hypertrophic burn scars in a pediatric population. Our findings suggest that laser therapy is a highly beneficial treatment for burn-injured children that should be integrated into current scar treatment practices. In addition to obtaining strong evidence to support the use of laser therapy, we utilized rigorous scar assessment and laser treatment protocols that can be easily adopted by other clinicians.

143 Galunisertib Exerts Targeted Anti-Fibrotic Effects in In Vitro Models of Burn Wound Healing

Abstract Introduction Inhibition of TGF-β has shown promising in vitro and in vivo results for reduction of hypertrophic scarring after burn injury. However, TGF-β regulates diverse cellular pathways apart from fibrosis, including physiologic wound healing, cell cycle control, and homeostasis. Galunisertib, a novel small molecular tyrosine kinase inhibitor of TGF-beta receptor type 1, specifically targets downstream pro-fibrotic pathways of TGF-β signaling, has an excellent adverse effect profile, and minimal off-target effects. We hypothesized that galunisertib diminishes fibrotic phenotypes in a targeted fashion, making it a promising candidate drug for prevention of hypertrophic burn scar and contracture. Methods Commercially available fibroblasts were treated with TGF-β at concentrations typical of burn wounds to induce fibrotic phenotype fibroblasts (FPF). FPF cells were treated with galunisertib for 0, 1, 2, 3, and 7 days at concentrations ranging from 0.01 μM to 100 μM. FPF viability and proliferation were assessed with MTT assay. Modulation of FPF cell fibrotic gene and was analyzed using quantitative real-time PCR (qRT-PCR) of COL1A1, COL3A1, FN1, αSMA, CTGF, DCN, MMP1, and MMP13. Analysis of phenotype modulation was performed by western blotting of P-Smad2/3, collagen-1, fibronectin, and αSMA. Statistical analysis performed with students t-test and ANOVA. Results TGF-β treated FPF cells had significantly increased proliferation relative to commercially available fibroblasts, which was attenuated by treatment with 2.5–10 μM galunisertib at 2 or 3 days after treatment in a concentration dependent manner (p &amp;lt; 0.05) while also not causing a relative decrease in proliferation. Expression of FPF downstream pro-fibrotic genes underwent significant fold changes (FN1, αSMA, CTGF: p &amp;lt; 0.05). Protein expression showed decrease in both SMAD2/3 phosphorylation and fibrotic protein expression. Scratch assay analysis is ongoing. Conclusions Galunisertib exerts targeted dose-dependent inhibition of fibrotic gene expression and phenotypes in vitro without hindering cellular proliferation.

34 Rete Ridges are Decreased in Dyschromic Burn Hypertrophic Scar: A Histological Study

Abstract Introduction Dyschromic hypertrophic scar (HTS) with areas of hyper- and hypo-pigmentation is a common sequelae of burn injury. The mechanism behind the development of dyschromia has not been elucidated. In this study, we provide a histological analysis of these scars with a focus on rete ridge presence. Rete ridges occur in epithelial tissues such as oral mucosa and skin and can be described as undulating “pegs” that are interdigitated with dermal papillae. Rete ridges enhance adhesion of the epidermis to the dermis. We hypothesize that rete ridge presence is important for normal skin physiology, and their absence or presence may hold mechanistic significance in post-burn HTS dyschromia. Methods Subjects with post-burn dyschromic HTS were consented and enrolled (n=27). Punch biopsies of hyper-, hypo-, and normally pigmented scar and skin were collected and stored in formalin. Biopsies were paraffin embedded, sectioned, stained with H&amp;E, and imaged. The number of rete ridges were investigated by calculating a rete ridge ratio from the length of the basement membrane and the length of the epidermis. Results The patient population was predominantly female (55.5%), black (70.4%), and had Fitzpatrick skin Type V (51.9%). The injuries were primarily as a result of flame (37%) and scald (33.3%) and resulted in a median TBSA burn of 7%. The median age of the scar at the time of sample acquisition was 12.2 months. The rete ridge ratio of normally pigmented, un-injured skin was above 1 (1.31 ± 0.04), indicating that normal skin’s basement membrane is longer than its epidermal length due to the presence of rete ridges. HTSs resulting from burn wounds that healed without split thickness autografts were first investigated. The number of rete ridges was higher in normal skin compared to HTS that was either hypo- or hyperpigmented (1.31 ± 0.04 vs. 1.13 ± 0.05 and 1.14 ± 0.04 vs, p&amp;lt; 0.05). This difference was similar despite pigmentation phenotype. When hyper-pigmented scars resulting from wounds that were treated with split thickness autografts (Hyper(+)) were investigated, rete ridge number was significantly higher than in Hyper(-) (1.89 ± 0.23, p&amp;lt; 0.01). Patient age showed a weak correlation (R=-0.33) with rete ridge ratio where older patients had lower rete ridge ratios in normal, un-injured skin. Hyper(+) showed a weak correlation between rete ridge ratio and age of scar (R=-0.38). Conclusions Post-burn HTS that is dyschromic has fewer rete ridges than normal skin. This finding may explain the decreased epidermal barrier function that is associated with HTS.

Hypopigmented burn hypertrophic scar contains melanocytes that can be signaled to re-pigment by synthetic alpha-melanocyte stimulating hormone in vitro.

There are limited treatments for dyschromia in burn hypertrophic scars (HTSs). Initial work in Duroc pig models showed that regions of scar that are light or dark have equal numbers of melanocytes. This study aims to confirm melanocyte presence in regions of hypo- and hyper-pigmentation in an animal model and patient samples. In a Duroc pig model, melanocyte presence was confirmed using en face staining. Patients with dyschromic HTSs had demographic, injury details, and melanin indices collected. Punch biopsies were taken of regions of hyper-, hypo-, or normally pigmented scar and skin. Biopsies were processed to obtain epidermal sheets (ESs). A subset of ESs were en face stained with melanocyte marker, S100β. Melanocytes were isolated from a different subset. Melanocytes were treated with NDP α-MSH, a pigmentation stimulator. mRNA was isolated from cells, and was used to evaluate gene expression of melanin-synthetic genes. In patient and pig scars, regions of hyper-, hypo-, and normal pigmentation had significantly different melanin indices. S100β en face staining showed that regions of hyper- and hypo-pigmentation contained the same number of melanocytes, but these cells had different dendricity/activity. Treatment of hypo-pigmented melanocytes with NDP α-MSH produced melanin by microscopy. Melanin-synthetic genes were upregulated in treated cells over controls. While traditionally it may be thought that hypopigmented regions of burn HTS display this phenotype because of the absence of pigment-producing cells, these data show that inactive melanocytes are present in these scar regions. By treating with a pigment stimulator, cells can be induced to re-pigment.

Comparison between the portable pressure measuring device and PicoPress® for garment pressure measurement on hypertrophic burn scar during compression therapy

PurposeThe current standard treatment for hypertrophic scars following burn injury is pressure garment therapy. The experimenters developed the novel portable pressure measuring device using silicon piezoresistive sensors. As PicoPress® is the most accurate (i.e., lowest variation and error) manometric sensor for pressure measurement, we sought to compare and examine the accuracy of the novel device regarding in vitro pressure measurements at the hypertrophic scar–pressure garment interface. MethodsThe novel device was designed to operate in non-corrosive media, such as air. The device can use up to six pressure sensing points and was developed to adjust the number of pressure sensors according to the size of the scar. Pressure measurements were acquired through a readout circuit consisting of an analog-to-digital converter, a microprocessor, and a Bluetooth transmission module for wireless data transmission to an external device. All signals were converted into mean pressure expressed in millimeters of mercury (mmHg). The mean pressure values measured by the sensors were compared to those obtained from PicoPress®. 55 garment pressures recordings were obtained from the sensors over this study conducted in 2018–February 2020. We then analyzed the test–retest reliability using the intraclass correlation coefficients (ICC). PicoPress® was also employed in the same pressure garments for obtaining similar measurements. A two way random effects model ICC with 95% confidence intervals was used to compare the mean pressure values obtained from the silicon piezoresistive sensors to the PicoPress® measurements. ResultsThe test–retest reliability of the pressure sensors was close to the acceptable level for clinical use regarding stationary interface pressure measurement (ICC = 0.99, 95% CI 0.990−0.997). The mean pressure obtained from the silicon piezoresistive pressure sensors showed an accordance with the measurements from PicoPress® (ICC = 0.97, 95% CI 0.947−0.985). ConclusionThe novel device may present a viable alternative to PicoPress® for garment pressure measurements. In addition, the novel device improves adaptability to the hypertrophic scar shape and size. Complementary characteristics such as wireless transmission to an external device may allow burn patients to continuously wear the device for real-time measurements during pressure garment therapy, thus improving existing devices including PicoPress®.

A retrospective study to identify the optimal parameters for pulsed dye laser in the treatment of hypertrophic burn scars in Chinese children with Fitzpatrick skin types III and IV.

For over several decades, 595-nm pulsed dye laser (PDL) has been used effectively, reducing erythema and improving the pliability and texture of burn scars. Children usually tolerate PDL treatment as it is non-invasive and causes only mild pain compared to other laser treatments. However, currently, there are limited data on scar management in children who underwent PDL treatment, especially for Fitzpatrick skin types III and IV. The objective of the study was to identify the optimal parameters for the PDL treatment that induce inhibitory effects on scar tissue in children with Fitzpatrick skin types III and IV. Besides, the study assessed the usefulness of high-frequency ultrasound (20 MHz) and laser Doppler flowmetry in assessing these lesions. A total of 165 (79 males and 86 females) children with hypertrophic scars treated by PDL were assessed by the Vancouver scar scale (VSS), high-frequency ultrasound (20 MHz), and laser Doppler flowmetry. The parameters used for the 595-nm PDL treatment were pulse duration of 0.45 ms, fluence between 5 and 9 J/cm2, a spot size of 7 mm, and treatment intervals from 3 to 8 weeks. There were no significant differences between pretreatment and post-treatment in terms of the distribution of sex, type of skin color, and low and high fluences. While the mean scores of all scar parameters based on VSS, except thickness and pliability between pre and post-treatment, showed significant differences in ≤3-year-old children vs. to >3-year-old children, except for the subscore, a significant improvement was observed when PDL was initiated within 4 to 6 months of the scar age. In Chinese children with Fitzpatrick skin types III and IV, early intervention, appropriate treatment intervals, and low fluence of PDL were optimal parameters in treating hypertrophic burn scars. The combined high-frequency ultrasound and laser Doppler flowmetry assessment of scars helped assess these lesions and compare the efficacy of different treatment modalities.

Combination of ablative fractional carbon dioxide laser and platelet-rich plasma treatment to improve hypertrophic scars: a retrospective clinical observational study.

BackgroundHypertrophic scars are one of the main complications that affect the quality of life of patients after burns. Many methods have been shown to be effective in the treatment of hypertrophic scars, such as ablative fractional CO2 laser (AFCL) and platelet-rich plasma (PRP). However, there are few studies on the effect of the combined application of these measures. The purpose of this study was to explore the therapeutic effect of AFCL combined with PRP on hypertrophic burn scars.MethodsA retrospective clinical observation study was conducted on 50 patients with hypertrophic burn scars. The AFCL+PRP group included 31 patients who received AFCL combined with PRP treatment; the AFCL group included 19 patients who received AFCL treatment only. The University of North Carolina 4P Scar Scale (UNC4P) and the Vancouver Scar Scale (VSS) scores that were collected before each treatment were used as indicators of the effectiveness of the previous treatment. The scores recorded at the second, fourth and seventh months were analysed.ResultsThe demographic data of the 2 groups were not significantly different. Before treatment, there was no difference in the UNC4P and VSS scores between the 2 groups. There was a significant decline in the UNC4P and VSS total scores over 6 months in both groups (p < 0.05) and scores in the 2 groups were comparable after 3 and 6 months (p < 0.05). UNC4P scores in the AFCL+PRP group decreased from a mean of 8.26 to 2.61 (p < 0.05) with a concomitant drop in VSS scores from a mean of 11.74 to 6.06 (p < 0.01). In the AFCL group UNC4P and VSS scores decreased from 7.68 to 4.63 (p < 0.05) and from 10.89 to 8.16 (p < 0.05), respectively. The sub-items of these 2 assessments were analysed and the results suggest that AFCL combined with PRP can comprehensively improve scarring.ConclusionsThis study shows that PRP is an effective adjunct for AFCL in the treatment of hypertrophic burn scars and that the combination of PRP and AFCL proved to be more useful than AFCL alone. This combination may be a new and effective clinical practice for the treatment of scars. However, larger and higher-level clinical studies are still needed to determine its efficacy and possible mechanisms.

Effects of combined Pulsed Dye Laser and Fractional CO2 Laser treatment of burn scars and correlation with plasma levels of collagen type I, MMP-2 and TIMP-1

Hypertrophic burn scars remain a significant burden for patients and a challenge for clinicians. The aimAssessement of the efficacy of combined Pulsed Dye Laser and Ablative Fractional CO2 Laser therapy on hyperthophic scars and correlation with plasma levels of MMP-2, TIMP-1 and alpha-1 type I collagen. Patients and methodsTwenty five pediatric subjects were enrolled into the study. Control group consisted of age-matched subjects admitted for surgical repair of inguinal hernia. For the assessment of the results of laser treatment we used the Vancouver scar scale (VSS), and Patient-Observer Scar Assessment Scale (POSAS). We also correlated clinical results with plasma levels of MMP-2, TIMP-1 and alpha-1 type I collagen. ResultsAll subjects reported the laser treatment resulted in improvement and were somewhat satisfied or very satisfied with their experience. No adverse events were reported. The levels of MMP-2, TIMP-1 and alpha-1 type I collagen in our patients with scars before laser threatment were higher in comparison to controls. We also found statistically significant decrease in the levels of MMP-2, TIMP-1 and alpha-1 type I collagen after laser treatment of burn scars ConclusionsOur study clearly shows that combined CO2-AFL treatment for burn scars improve texture, colour, function and alleviate pruritus. We believe that decrease in the levels of MMP-2, TIMP-1 and alpha-1 type I collagen after laser treatment of burn scars, reflects reduced dynamic of scar.

Combination treatment utilizing fractional ablative and continuous wave CO2 lasers for hypertrophic burn scars

BackgroundHypertrophic scars are devastating outcomes of severe burn injuries, producing physical and mental burdens. Adequate treatment is of benefit to relieve these burdens. Laser therapy has shown scar reducing effects. In this study, we compared outcomes after combination of two different lasers or single laser treatment to treat severe hypertrophic burn scars. MethodsForty patients with hypertrophic burn scars were included in one of two therapeutic groups: continuous wave CO2 laser and fractional ablative CO2 laser group (group 1, n = 20) or fractional ablative CO2 laser alone group (group 2, n = 20). Hypertrophic scars were evaluated by the observer-rated Vancouver Scar Scale (VSS) before and after treatment and by patient-completed questionnaires after treatment. Comparative analyses were performed before and after treatment, and time-dependent improvement was also analyzed. ResultsForty patients (54 hypertrophic scars) completed the laser treatment protocols. Group 1 exhibited significantly more improvement in VSS vascularity, pliability, and height indices than group 2 (p < 0.05). Time-dependent analysis of total VSS scores suggested that group 1 experienced more improvement during a shorter treatment period (p < 0.05). For patient-reported outcomes, group 1 noted better grades than group 2 in four indices, namely scar appearance, scar thickness, pain, and pruritus (p < 0.05). ConclusionEffective scar reduction was achieved using combination laser treatment, with significant improvement in multiple observer- and patient-reported outcomes. The shorter treatment period of the combination method can be a merit, as prolonged hypertrophic scars may increase morbidity. Nonetheless, cautious treatment protocols are necessary to avoid undesirable sequelae related to laser application.

Early Treatment Effects of Nonablative Fractional Lasers (NAFL) on Hypertrophic Scars in an Animal Model.

Recently, there have been several attempts to apply the laser therapy to hypertrophic scars (HTS). In particular, the fractional laser is in the spotlight for its usefulness in rapid wound healing and dermal remodeling. However, most previous studies have focused on the ablative fractional laser (AFL), and there are no studies on the mechanism of the nonablative fractional laser (NAFL) effect in HTS treatment. In this study, we aimed to evaluate the changes in histology and molecular chemistry to provide scientific evidence for the early treatment of HTS with NAFL. A total of 40 hypertrophic burn scars were made on the abdomens of two female pigs. After epithelialization, the HTS were randomly subdivided into four groups-control, AFL, NAFL (low energy), and NAFL (high energy). Laser treatment was initiated 1 week after the crust fell and the epithelium became covered, and it was repeated for six sessions over an interval of 2 weeks. Five excisional biopsies were obtained for histologic analysis and biomarker assessment. Histologically, dermal remodeling with thin coil-shaped collagen fibers was observed in the NAFL groups. It also showed a significant increase of matrix metalloproteinase-2 (MMP-2) and Decorin at 16 weeks in an enzyme-linked immunosorbent assay. The reverse-transcription polymerase chain reaction analysis showed a tendency that high-pulse energy of NAFL led to higher messenger RNA expression than did the low-energy group. The NAFL-treated groups showed characteristic collagen re-arrangement and a significant increase in MMP-2 and Decorin. These molecular changes suggest that MMP-2 and Decorin play a significant role in dermal remodeling. Early NAFL treatment for HTS could be supported with both histological and molecular evidence. Lasers Surg. Med. © 2020 Wiley Periodicals, Inc.

Hypertrophic Scars: A Retrospective Review of Etiologies, Treatments, and Outcomes

PURPOSE: We conducted the current study to review our clinical experience managing hypertrophic scars. Our primary aim was to investigate the outcomes of nonsurgical and surgical treatments intended to remove or reduce hypertrophic scars. The secondary aim was to investigate anatomical locations and nonsurgical and surgical treatments between burn and nonburn etiologies of hypertrophic scars. Tertiary aims were to assess responses to therapy and recurrence rates associated with different laser settings. METHODS: A retrospective analysis of a consecutive cohort of patients whose hypertrophic scars were managed and followed up in clinic from January 1, 2017 to January 1, 2019. Patients were included if they were ≥18 years of age and had a documented diagnosis of a hypertrophic scar. Patients were excluded if they did not follow-up after hypertrophic scar treatment or if they had a keloid scar diagnosis. Primary outcomes measured were hypertrophic scar treatment modalities and corresponding changes in pain scores, changes in pruritus scores, and recurrence rates following treatments. Secondary outcomes measured were scar locations, previous treatments, previous surgery in scar location, subsequent treatments, and postsurgical adjuvant therapy between burn and nonburn etiologies. Tertiary outcomes measured were responses to therapy and recurrence rates associated with laser types, settings and handpiece options. RESULTS: One hundred forty-two patients (mean age, 40.6 ± 15.9 years) had 595 hypertrophic scars. Median length of follow-up was 10.1 months (interquartile range, 7.3–14.8 months). Surgery or lasers were associated with significant changes in pruritus scores compared to corticosteroid injections or topical steroids alone (P = 0.01). Lasers or corticosteroid injections were associated with significantly lower recurrence rates compared to surgery or topical corticosteroids alone (P = 0.03). Lasers significantly increased the odds of decreased pain scores (odds ratio, 1.03; 95% CI, 0.1–1.9; P = 0.023) and no changes in pruritus scores. Lasers significantly reduced the odds of scar recurrence (odds ratio, 0.12; 95% CI, 0.04–0.41; P = 0.001). Burn scars were more commonly located on the face/head (15% versus 7.5%; P < 0.001), upper arm/forearm (40.5% versus 12.3%; P < 0.001), posterior torso (6.5% versus 1.9%; P = 0.005), and thigh/leg (15% versus 1.9%; P < 0.001) compared to nonburn scars. Nonburn scars were more commonly located at the hands compared to burn scars (14.1% versus 7%; P = 0.007). Burn scars were more commonly treated with lasers compared to nonburn scars (98.8% versus 19.9%; P < 0.001). Nonburn scars were more commonly treated with surgery (18.8% versus 10.2%; P = 0.03) and corticosteroid injections (75.5% versus 0.8%; P < 0.001) compared to burn scars. Different laser handpiece options were significantly associated with successful responses to therapy (DeepFX = 100%, SCAAR FX = 65.8%, and ActiveFX = 48%; P = 0.014). CONCLUSIONS: Lasers increased the odds of decreased pain scores and no changes in pruritus scores for all etiologies of hypertrophic scars. Laser use reduced the odds of scar recurrence for all etiologies of hypertrophic scars. Hypertrophic burn scars were more commonly located on the face/head, upper arm/forearm, posterior torso, and thigh/leg, whereas hypertrophic nonburn scars were more commonly located on the hands. Hypertrophic burn scars had the greatest response rates with the laser handpiece DeepFX.

Ablative fractional laser treatment of hypertrophic burn and traumatic scars: a systematic review of the literature.

Hypertrophic scars (HTS) following burns and other trauma and are associated with significant functional and psychosocial impairment. Ablative fractional lasers (AFLs) are increasingly being applied in the treatment of HTS supported by a rapidly expanding multidisciplinary base of literature. The multidisciplinary authors sought to evaluate existing literature, provide context and identify gaps, and make recommendations for a path forward. A systematic review was conducted to identify literature pertinent literature through September 2019. Retrospective cohort, randomized controlled trials, quasi-randomized controlled trials, observational prospective cohort, or case series with five or more subjects with hypertrophic scars incurred from burns and related trauma were considered. Twenty-two of the 23 evaluated studies documented statistically significant and/or meaningful qualitative improvements in nearly all outcome measures. Adverse events were generally infrequent and minor. Significant heterogeneity was observed among the studies included in this systematic review, precluding metaanalysis of pooled data. There is abundant existing literature on the use of AFLs in the management of HTS but study heterogeneity limits generalizability. Future studies should prioritize standardized protocols including assessments of function and quality of life.

Fractionated Ablative Carbon Dioxide Laser Therapy Decreases Ultrasound Thickness of Hypertrophic Burn Scar: A Prospective Process Improvement Initiative.

Carbon dioxide (CO2) laser treatment is routinely used to treat hypertrophic burn scars (HBS). Although prior research has documented subjective improvement in HBS after treatment, there is little data evaluating objective changes in scar characteristics after therapy. The aim of our process improvement project was to evaluate changes to scar thickness (ST) using high-frequency ultrasound in patients with HBS undergoing CO2 laser therapy. Ultrasound measurements of ST were obtained from patients with HBS before initial and at each subsequent treatment. ST, reduction in ST per treatment, and percentage reduction in ST from baseline were tabulated. Post hoc analyses examining the effect of initial ST and scar maturity on outcome were performed. First, patients were grouped by baseline ST into thicker (group 1, initial ST ≥ median value) and thinner (group 2, initial ST < median value) scar groups. Second, patients were divided into quartiles based on time from injury to treatment. Outcomes at each time point were compared with either Mann-Whitney U or Kruskal-Wallis tests, with Bonferonni corrections performed for post hoc subgroup analyses. Significance was set at P < 0.05. Twenty-one consecutive patients with HBS treated with CO2 laser were included. All patients completed 1 or more treatment, 48% completed 2 or more treatments, and 28% completed 3 treatments. Median initial ST was 0.71 cm (0.44-0.98 cm), and median scar maturity was 7.5 months (4.9-9.8 months). Overall, ST decreased over the treatment course (P < 0.001), with post hoc analysis demonstrating that 2 treatments were required to achieve a significant ST reduction (P < 0.01). On subgroup analysis comparing initial ST, ST decreased significantly in group 1 (thicker scars) overall (P < 0.001) but not in group 2 (P = 0.109). ST reduction was greatest after 1 treatment in group 1 (P = 0.022) and group 2 (P = 0.061). Percent reduction was greater in group 1 relative to group 2 after 1 treatment (P = 0.016). On subgroup analysis of scar maturity, there were no significant differences in either baseline ST or ST at any subsequent visit. Fractionated ablative CO2 laser treatment improved ST after 1 to 2 treatments. Patients with thicker scars demonstrated greater ST reduction than those with thinner scars. Ultrasound adequately assessed treatment response.

Hypertrophic Scar Improvement by Early Intervention With Ablative Fractional Carbon Dioxide Laser Treatment.

Ablative fractional laser treatment has been used to improve the color and texture of hypertrophic scars with safe and effective results. However, no consensus on the optimal time to initiate fractional laser treatment is available. The effect on early-stage scars remains controversial. This study was designed to assess the efficacy and safety of ablative fractional carbon dioxide (CO2 ) laser treatments for hypertrophic burn scars and to analyze the efficacy and safety in the early period within 3 months after injury. We performed a retrospective study of 221 hypertrophic scar patients. According to the time of the first laser treatment after injury, patients were divided into five subgroups, including less than 1 month, 1-3 months, 3-6 months, 6-12 months, and more than 12 months postinjury. One month after the last laser treatment, the scars were assessed by photography, the Vancouver Scar Scale (VSS), durometry, and spectrocolorimetry. The patients included 118 males and 103 females. The average age was 33.6 years. Fire/flame was the primary injury source. Thirty-six percent of the patients underwent at least one fractional CO2 laser treatment. All the included patients, including those treated within 1 month after injury, had significantly decreased VSS scores after laser treatment. We also noted that hardness and redness scores were decreased after treatment for both scars treated within 3 months and those treated more than 12 months after injury. Seepage (17.6%), bleeding (22.2%), and swelling (9.0%) were the main adverse events after laser treatment. This study demonstrated the safety and efficacy of ablative fractional CO2 laser treatment applied to early-stage burn scars. The optimal time for laser application for burn patients can be within 1 month after injury. Durometry and spectrocolorimetry were effective for assessing scars as objective modalities. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Commentary on Treatment of Hypertrophic Burn and Traumatic Scars With 2940 mm Fractional Ablative Er: YAG.

Commentary on Treatment of Hypertrophic Burn and Traumatic Scars With 2940 mm Fractional Ablative Er: YAG.

Within-Patient, Single-Blinded, Randomized Controlled Clinical Trial to Evaluate the Efficacy of Triamcinolone Acetonide Injections for the Treatment of Hypertrophic Scar in Adult Burn Survivors

Intralesional corticosteroid (triamcinolone acetonide [TAC]) injections have become one of the cornerstone treatments of hypertrophic scar (HSc). However, the evidence is of limited-quality, and published investigations have almost exclusively been performed in linear scars rather than hypertrophic burn scars. Thus, the aim of this study was to perform an appropriately powered, single-blinded, randomized controlled trial to evaluate the impact of TAC injections on burn HSc compared with patient-matched usual care control scars. Fifty burn survivors with two scars (separated by nonscarred skin preferably on the contralateral side or an anatomically similar site) were selected based on high-frequency ultrasound thickness (>2.034 mm to ensure that the site was outside of the range of normal scar). Pretreatment thickness measurements of the two sites were within 0.5 mm of each other, to ensure homogeneity and an erythema index >300 to establish they were immature HSc. The sites were randomly assigned to treatment or control. The treatment HSc received a 10 mg/ml TAC. When necessary, the injection was repeated after 6 weeks and a third final injection 6 weeks later. Objective evaluation of thickness, elasticity, erythema, and melanin was obtained at the treatment and control sites at pretreatment, posttreatment, and follow-up 6 weeks after the last injection. Thirty participants completed the study, reaching the required number for an adequately powered sample based on pilot study data analyses. Ten participants received only one injection, 27 received only two injections, and 13 received three injections of TAC. Analysis of covariance comparing the treatment vs control HSc posttreatment, controlling for pretreatment values and Fitzpatrick skin type, revealed a significant decrease in thickness and increase in elasticity of the treated compared with control HSc (P = .0003), but no significant difference in erythema or melanin. Pretreatment to posttreatment comparisons using paired t-tests revealed a significant decrease in thickness of both the treated and control HSc, an increase in elasticity of the treated HSc during the treatment period, but no significant change in the control HSc elasticity or erythema of either site, and a significant increase in melanin of both the treated (P < .001) and control (P = .02) HSc. A regression model for repeated measures, controlling for pretreatment values and skin type, revealed no significant change in thickness, elasticity, erythema, or melanin during the 6-week follow-up. Although thickness decreased at both the treated and control HSc across time, there was a significantly greater reduction at the TAC injected HSc and a significantly greater increase in elasticity. Melanin significantly increased at both the treatment and control site. There was no significant change during the follow-up period of any of the HSc characteristics.