Laser therapy for treating hypertrophic and keloid scars

Local adjuncts to minimally invasive endoscopic interventions for benign laryngotracheal stenosis: a meta-analysis

BACKGROUND

Benign laryngotracheal stenosis is widely managed with minimally invasive endoscopic interventions, such as laser incision or excision scar, and dilation. However, various endoscopic treatments are significantly associated with a high recurrence rate. Local auxiliary measures, including inhalation of steroids, injection of steroids, and local topical application of mitomycin C, have been studied in order to increase the success rate.

PURPOSE

To compare the efficacy of endoscopic treatments with and without local adjuncts in patients with benign laryngotracheal stenosis, and analyze their clinical outcomes, recurrence, and complications.

METHODS

In the meta-analysis, databases including PubMed, EMBASE, OVID, and Web of Science were searched for papers comparing the outcomes of adjunct therapy with non-adjunct therapy in patients with laryngotracheal stenosis. The duplicate publications, reviews, comments or letters, conference abstracts, and case reports were excluded. The random effect model was used for assessing the pooled risk estimates.

RESULTS

Eight studies (1204 cases) referring to two prospective randomized controlled studies, two prospective cohort studies, and four retrospective cohort studies were ultimately included in the meta-analysis. Three delivery modes of adjuncts were identified, including intralesion steroid injection (n = 2), inhaled steroid (n = 2), and topical application of mitomycin C (n = 4). The decreased risk estimates of recurrence rate were detected in patients receiving endoscopic treatments with steroid injection or inhaled steroid, compared with endoscopic interventions alone (P < 0.05). Additionally, patients undergoing adjunct therapies had lower risk estimates of recurrence, compared to those receiving endoscopic procedures alone (P < 0.05), based on the subgroup of prospective cohort studies, subglottis, Mayer-Cotton scale of I-II degree, and stenosis length of < 3 cm. The high heterogeneity of the pooling risk estimates perhaps was due to factors of auxiliary drug, clinical characteristics of patients, and methodology. No discernible difference in the incidence of complication was identified.

CONCLUSIONS

Local application of steroids to minimally invasive interventions appear to reduce the recurrence rate of laryngotracheal stenosis. Various adjuncts available, including steroids and mitomycin C, appear to be safe and associated with a low risk estimate of adjuncts-specific complication rate. High quality multi-center randomized controlled studies are needed, with sufficient periods for follow-up and subjective and objective outcome indicators, to properly evaluate the efficacy, safety, and cost-effectiveness of adjuvant drugs.

Laser-mediated Solutions: Breaking Barriers in Transdermal Drug Delivery

Skin diseases pose challenges in treatment due to the skin's complex structure and protective functions. Topical drug delivery has emerged as a preferred method for treating these conditions, offering localized therapy with minimal systemic side effects. However, the skin's barrier properties frequently limit topical treatments' efficacy by preventing drug penetration into deeper skin layers. In recent years, laser-assisted drug delivery (LADD) has gained attention as a promising strategy to overcome these limitations. LADD involves using lasers to create microchannels in the skin, facilitating the deposition of drugs and enhancing their penetration into the target tissue. Several lasers, such as fractional CO2, have been tested to see how well they work at delivering drugs. Despite the promising outcomes demonstrated in preclinical and clinical studies, several challenges persist in implementing LADD, including limited penetration depth, potential tissue damage, and the cost of LADD systems. Furthermore, selecting appropriate laser parameters and drug formulations is crucial to ensuring optimal therapeutic outcomes. Nevertheless, LADD holds significant potential for improving treatment efficacy for various skin conditions, including skin cancers, scars, and dermatological disorders. Future research efforts should focus on optimizing LADD techniques, addressing safety concerns, and exploring novel drug formulations to maximize the therapeutic benefits of this innovative approach. With continued advancements in laser technology and pharmaceutical science, LADD has the potential to revolutionize the field of dermatology and enhance patient care.

A Comprehensive Review of Non-Surgical Treatments for Hypertrophic and Keloid Scars in Skin of Color

Hypertrophic and keloid scars are fibroproliferative growths resulting from aberrant wound healing. Individuals with Fitzpatrick skin types (FSTs) IV-VI are particularly predisposed to hypertrophic and keloid scarring, yet specific guidelines for these populations are still lacking within the literature. Therefore, this comprehensive review provides a list of various treatments and considerations for hypertrophic and keloid scarring in patients with skin of color. We constructed a comprehensive PubMed search term and performed quadruple-blinded screening on all resulting studies to achieve this objective. Our findings demonstrate 1) the lack of efficacious treatments for raised scars within this population and 2) the need to empirically investigate individualized and multimodal therapeutic options for those with skin of color.

Laser Therapy in Hypertrophic and Keloid Scars: A Systematic Review and Network Meta-analysis

BACKGROUND

Laser therapy has emerged as a promising treatment modality for improving the appearance and symptoms associated with hypertrophic and keloid scars. In this network meta-analysis, we aimed to evaluate the efficacy of different laser types in treating hypertrophic and keloid scars.

METHODS

A comprehensive search of four databases was conducted to identify relevant studies published up until July 2023. Data were extracted from eligible studies and pooled as mean difference (MD) for continuous outcomes and risk ratio (RR) for dichotomous data in a network meta-analysis (NMA) model, using R software.

RESULTS

A total of 18 studies, comprising 550 patients, were included in the analysis. Pooling our data showed that fractional carbon dioxide (FCO2) plus 5-fluorouracil (5-FU) was superior to control in terms of Vancouver Scar Scale (VSS), pliability score, and thickness; [MD = - 5.97; 95% CI (- 7.30; - 4.65)], [MD = - 2.68; 95% CI (- 4.03; - 1.33)], [MD = - 2.22; 95% CI (- 3.13; - 1.31)], respectively. However, insignificant difference was observed among FCO2 plus 5-FU compared to control group in terms of erythema, vascularity, redness and perfusion, and pigmentation [MD = - 0.71; 95% CI (- 2.72; 1.30)], [MD = - 0.44; 95% CI (- 1.26; 0.38)], respectively.

CONCLUSION

Our NMA found that the FCO2 plus 5-FU was the most effective intervention in decreasing the VSS and thickness, while FCO2 plus CO2 was the most effective intervention in decreasing the pliability score. Further research is needed to determine the optimal laser parameters and long-term efficacy of laser therapy in hypertrophic and keloid scars.

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 .

Knowledge and Practice of Scar Treatment Among Health Care Physicians in Saudi Arabia

Background The processes of wound healing and scar formation are complex phenomena that are determined by an intricate interplay of molecules and cells. A deviation from the anticipated trajectory of scarring can lead to the formation of hypertrophic scars and keloids. A wide range of therapeutic methodologies have been employed in the treatment of scars. This research paper seeks to enhance patient outcomes and the efficacy of scar repair as a whole by determining the knowledge of scar treatment and implementation in clinical practice in Saudi Arabia and thereby incorporating scientific findings into practical settings. Materials and methods This cross-sectional study, which included 237 participants, aimed to provide descriptive data on the knowledge and common practice of Saudi Arabian healthcare physicians with regard to scar prevention, treatment, and evaluation during the period from November 15, 2023, to December 11, 2023. Results In routine clinical practice, the most commonly employed subjective method for scar assessment is patient and observer scar assessment (162 (68.4%)) while the Modified Vancouver Scar Scale (91 (38.4%)) was commonly used for research purposes. However two-dimensional photography is the most frequently employed objective method in clinical practice (54 (22.8%)) and biomechanical properties (58 (24.5%)) for research purposes. Silicone scar therapy in the form of sheets or gel is the primary preventive measure in the prevention of keloids/hypertrophic scars across various patient populations. Corticosteroid injections and silicone are primary interventions within the initial 18-month period. Conclusion Although significant progress has been made in the field of scar management, standardization of procedures and increased adherence to evidence-based guidelines are still required.

The Effect of Fat Grafting on Scars Hyperpigmentation: A Systematic Review and Meta-Analysis

BACKGROUND

Hyperpigmented scars, particularly in exposed body areas, can be difficult to conceal and may evoke psychological distress. While the precise causes of scar dyschromia are not fully understood, alterations in melanogenic activity appear to hold more significance than changes in melanocyte quantity. Current treatments encompass laser interventions. However, it is essential to consider their costs and potential complications in relation to their limited proven effectiveness. Fat grafting has gained interest as a scar modulation technique due to its regenerative properties, and its efficacy in reducing scar hyperpigmentation is currently under investigation.

METHODS

A systematic review and meta-analysis was reported according to PRISMA guidelines. PubMed, Embase, and Cochrane Library databases were accessed. PROSPERO registration number is CRD42023457778. The primary outcome was a change in scar pigmentation after fat grafting. Pigmentation changes after fat grafting were calculated using the standardized mean difference (SMD) between baseline and postoperative scores according to POSAS and VSS scales. Bias assessment was conducted according to the National Institute for Health and Clinical Excellence quality assessment tool.

RESULTS

A total of 8 articles meeting inclusion and exclusion criteria were identified, involving 323 patients with hyperpigmented scars treated with fat grafting. A significant difference in scar pigmentation was noted after treatment with fat grafting according to observers' ratings, with a SMD of - 1.09 [95% CI: - 1.32; - 0.85], p<0.01. The SMD for patient-reported scar pigmentation after treatment with fat grafting was - 0.99 [96% CI: - 1.31; - 0.66], p<0.01. Four studies provided objective measurements of melanin changes after fat grafting and revealed inconsistent findings compared to subjective observations.

CONCLUSIONS

Fat grafting shows promise in ameliorating hyperpigmented scars based on subjective assessments, but further corroborating evidence from objective measures is required.

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 .

The Comparison of Efficacy and Safety Between General and Topical Anesthesia on Micro-Plasma Radiofrequency Treatment for Hypertrophic Scar: A Retrospective Cohort Study

BACKGROUND

While micro-plasma radiofrequency (MPR) treatment has a significant impact on hypertrophic scars, patients often require anesthesia to alleviate substantial discomfort. Currently, patients with similar degrees of scarring may choose surface anesthesia or general anesthesia based on their personal preferences. Nevertheless, the effectiveness and safety of different anesthesia modalities remain uncertain.

OBJECTIVE

To assess the effectiveness and safety of both general and surface anesthesia in MPR treatment for hypertrophic scars.

METHODS

We conducted a retrospective cohort study involving 101 patients diagnosed with hypertrophic scars who underwent MPR with different anesthesia methods. The primary measures of efficacy included the Vancouver Scar Scale (VSS) scores assessed before the first treatment and six months after the final treatment. Pain relief was evaluated using Visual Analog Scale (VAS) scores. Safety was assessed by comparing the incidence of adverse reactions between the two groups.

RESULTS

Patients in the general anesthesia group showed a significant difference in scar pigmentation 6 months after the treatment and lower pain level than those in the surface anesthesia group in the treatment of MPR. The difference in safety was not statistically significant. After adjusting for confounding factors and propensity score matching, the outcome of VSS and VAS scores was stable.

CONCLUSION

General anesthesia, as opposed to surface anesthesia, appears to enhance both the effectiveness and safety of MPR while reducing postoperative pain in the treatment of hypertrophic scars. For patients with heightened pain sensitivity, general anesthesia may be the preferred treatment option.

LEVEL OF EVIDENCE II

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 http://www.springer.com/00266 .

Evidence-based rehabilitation medicine: definition, foundation, practice and development

To determine the definition, foundation, practice, and development of evidence-based rehabilitation medicine (EBRM) and point out the development direction for EBRM. Retrieve the database of PubMed, Cochrane Library, Embase, China national knowledge infrastructure (CNKI), Wanfang, and China science and technology journal database (CSTJ). The search was conducted from the establishment of the database to June 2023. The key words are "rehabilitation medicine and evidence based" in Chinese and English. After reading the abstract or full text of the literature, a summary analysis is conducted to determine the definition, foundation, practice, and development of EBRM. A total of 127 articles were included. The development of 14 sub majors in EBRM are not balanced, evidence-based musculoskeletal rehabilitation medicine (EBMRM) (31 articles, mainly focuses on osteoarthritis, osteoporosis and musculoskeletal pain), evidence-based neurorehabilitation medicine (EBNM) (34 articles, mainly concentrated in stroke, traumatic brain injury and spinal cord injury) and evidence-based education rehabilitation medicine (EBEDRM) (17 articles, mainly focuses on educational methodology), evidence-based nursing rehabilitation medicine (EBNRM) (2 articles), evidence-based engineering rehabilitation medicine (EBENRM) (7 articles), evidence-based traditional Chinese rehabilitation medicine (EBTCRM) (3 articles), evidence-based internal rehabilitation medicine (EBIRM) (11 articles), evidence-based intensive care rehabilitation medicine (EBICRM) (4 articles), evidence-based oncology rehabilitation medicine (EBORM) (6 articles), evidence-based physical therapy medicine (EBPTM) (3 articles), evidence-based cardiopulmonary rehabilitation medicine (EBCRM) (6 articles), evidence-based speech therapy medicine (EBSTM)/evidence-based occupation therapy medicine (EBOTM)/evidence-based geriatric rehabilitation medicine (EBGRM) (1 article). The EBMRM, EBNM and EBEDRM are relatively well developed. The development of EBNRM, EBENRM, EBTCRM, EBIRM, EBICRM, EBGRM, EBORM, EBCRM, EBPTM, EBSTM and EBOTM is relatively slow, indicating these eleven fields should be pay more attention in future.

Advances and future directions in keloid research: Pathogenesis, diagnosis and personalized treatment strategies

Keloids, which are abnormal manifestations of wound healing, can result in significant functional impairment and aesthetic deformities. The pathogenesis of keloids is multifaceted and complex and influenced by various factors, such as genetics, the environment, and immune responses. The evolution of keloid treatment has progressed from traditional surgical excision to a contemporary combination of therapies including injection and radiation treatments, among others. This article provides a comprehensive review of keloid pathogenesis and treatment, emphasizing the latest advances in the field. Ultimately, this review underscores the necessity for continued research to enhance our understanding of keloid pathogenesis and to devise more effective treatments for this challenging condition.

Scars

Wound healing occurs as a response to disruption of the epidermis and dermis. It is an intricate and well-orchestrated response with the goal to restore skin integrity and function. However, in hundreds of millions of patients, skin wound healing results in abnormal scarring, including keloid lesions or hypertrophic scarring. Although the underlying mechanisms of hypertrophic scars and keloid lesions are not well defined, evidence suggests that the changes in the extracellular matrix are perpetuated by ongoing inflammation in susceptible individuals, resulting in a fibrotic phenotype. The lesions then become established, with ongoing deposition of excess disordered collagen. Not only can abnormal scarring be debilitating and painful, it can also cause functional impairment and profound changes in appearance, thereby substantially affecting patients' lives. Despite the vast demand on patient health and the medical society, very little progress has been made in the care of patients with abnormal scarring. To improve the outcome of pathological scarring, standardized and innovative approaches are required.

Inhibition of keloid by 32P isotope radiotherapy through suppressing TGF-β/Smad signaling pathway

BACKGROUND

Keloid seriously affects the appearance, and is accompanied by some symptoms including pain, burning, itching. Radioactive nuclides such as 32P have been proved to be effective in inhibiting the formation of keloid, but the mechanism remains unclear.

METHODS

The keloid animal model was established through keloid tissues implantation. Hematoxylin-Eosin (HE) and Masson staining were performed to investigate histological changes and collagen deposition. The mRNA and protein expression were assessed using RT-PCR and western blotting, respectively. Cell apoptosis and cycle were evaluated through flow cytometry.

RESULTS

Both 32P isotope injection and skin path significantly reduced the size of keloid, and inhibited TGF-β/Smad signaling pathway. SRI-011381, the agonist of TGF-β/Smad signaling pathway, markedly reversed the influence of 32P isotope on cell proliferation, cell apoptosis, cell cycle of LNCaP cells and TGF-β/Smad signaling pathway.

CONCLUSIONS

32P isotope injection and skin path greatly reduced the size of keloid, and the TGF-β/Smad signaling pathway was remarkably inhibited by 32P isotope treatment. The regulation of dermal fibroblast by 32P isotope was reversed by SRI-011381. 32P isotope might inhibit keloid through suppressing TGF-β/Smad signaling pathway. Our study provides a novel therapeutic strategy for the treatment of keloid.

Characterization of the skin keloid microenvironment

Keloids are a fibroproliferative skin disorder that develops in people of all ages. Keloids exhibit some cancer-like behaviors, with similar genetic and epigenetic modifications in the keloid microenvironment. The keloid microenvironment is composed of keratinocytes, fibroblasts, myofibroblasts, vascular endothelial cells, immune cells, stem cells and collagen fibers. Recent advances in the study of keloids have led to novel insights into cellular communication among components of the keloid microenvironment as well as potential therapeutic targets for treating keloids. In this review, we summarized the nature of genetic and epigenetic regulation in keloid-derived fibroblasts, epithelial-to-mesenchymal transition of keratinocytes, immune cell infiltration into keloids, the differentiation of keloid-derived stem cells, endothelial-to-mesenchymal transition of vascular endothelial cells, extracellular matrix synthesis and remodeling, and uncontrolled angiogenesis in keloids with the aim of identifying new targets for therapeutic benefit. Video Abstract.

Advances in Immunomodulatory Mechanisms of Mesenchymal Stem Cells-Derived Exosome on Immune Cells in Scar Formation

Pathological scars are the result of over-repair and excessive tissue proliferation of the skin injury. It may cause serious dysfunction, resulting in psychological and physiological burdens on the patients. Currently, mesenchymal stem cells-derived exosomes (MSC-Exo) displayed a promising therapeutic effect on wound repair and scar attenuation. But the regulatory mechanisms are opinions vary. In view of inflammation has long been proven as the initial factor of wound healing and scarring, and the unique immunomodulation mechanism of MSC-Exo, the utilization of MSC-Exo may be promising therapeutic for pathological scars. However, different immune cells function differently during wound repair and scar formation. The immunoregulatory mechanism of MSC-Exo would differ among different immune cells and molecules. Herein, this review gave a comprehensive summary of MSC-Exo immunomodulating different immune cells in wound healing and scar formation to provide basic theoretical references and therapeutic exploration of inflammatory wound healing and pathological scars.

GEO data mining identifies potential immune-related genes in hypertrophic scar and verities in a rabbit model

Objective

Hypertrophic scar (HTS), the secondary major abnormal tissue after wound healing, is the most frequent and severe type of skin scar. Dysregulated immune response plays an important role in HTS formation. In this study, we identified the potential immune-related genes in HTS and explored their potential therapeutic significance.

Methods

We first screened out the potential immune-related genes in HTS microarrays via bioinformatics analysis using public datasets. We then constructed a rabbit model of ear scar to investigate the morphological features of HTS and verify the basic expression of potential immune-related genes in HTS tissue. Finally, we used AlphaFold to determine the protein homology between human and rabbit scar tissues.

Results

Bioinformatics analysis revealed 22 differentially expressed genes (DEGs) and a single differential infiltration of immune cells (naïve B cells) in HTS and normal tissues. Six of the DEGs were correlated with naïve B cell numerically. CCL2, PLXDC2 and FOXF2 were expressed in rabbit ear scar model. PLXDC2 and FOXF2 showed relatively high homology between human and rabbit scar tissues.

Conclusions

PLXDC2 and FOXF2, both closely related to immune cell infiltration and specifically expressed in HTS, represent potential therapeutic targets in HTS.