Efficacy and safety of Nd:YAG laser alone compared with combined Nd:YAG laser with intralesional steroid or botulinum toxin A in the treatment of hypertrophic scars

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

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Current Research of Botulinum Toxin Type A in Prevention and Treatment on Pathological Scars

BACKGROUND

Dermatologists have been looking for ways to improve wound healing and postoperative scar appearance. The safety and efficacy of botulinum toxin type A (BTXA) in the prevention and treatment on pathological scars have become the current research hotspot since it was approved by the US FDA in medical cosmetology in 2002.

PURPOSE

This article aims to provide an overview of the clinical research, limitations, and application prospects of BTXA in the prevention and treatment of traumatic or postoperative pathological scars, which can provide a reference and better understanding of relevant studies.

METHODS

The current research progress was summarized and discussed, with new problems and research ideas being proposed ranging from the molecular mechanism of BTXA in preventing and treating pathological scars to its clinical application via investigation and reference research.

RESULTS

BTXA is effective in relieving itching and pain associated with pathological scars, limiting scar hyperplasia along with preventing scar contracture, but the specific mechanism is still not clear.

CONCLUSION

Most of the clinicians have confirmed the clinical effectiveness of BTXA in the prevention and treatment of pathological scars, yet its mode of action and combination therapy need more research.

Pain Reduction With AbobotulinumtoxinA for the Treatment of Hallux Valgus in Adult Participants: Results of a Randomized and Placebo-Controlled Phase 2 Trial

AbobotulinumtoxinA (aboBoNT-A, Dysport® [Ipsen, Paris, France]) inhibits acetylcholine release at the neuromuscular junction and may modulate pain signaling in hallux valgus (HV). This randomized study (NCT03569098) included a double-blind phase (aboBoNT-A 300U, 500U or placebo injections into forefoot muscles) and an open-label aboBoNT-A treatment period in participants with an HV diagnosis and no HV surgery. The primary endpoint was change from baseline in numeric pain rating scale (NPRS) score at week 8. Secondary endpoints included change in NPRS (other time points) and proportion of participants with ≥20% reduction from baseline NPRS (responders). Post-hoc analyses assessed number of days in a 7-day evaluation period that participants spent in a lower pain state than at baseline. Participants received aboBoNT-A 300U (n = 63), 500U (n = 60) or placebo (n = 63). Superiority to placebo was not observed with either aboBoNT-A dose at week 8, thus the primary endpoint was unmet. At week 12, a trend toward efficacy was observed with aboBoNT-A 500U versus placebo and the proportion of participants with ≥20% reduction from baseline NPRS was greater with aboBoNT-A 500U versus placebo (p = .006). Participants in the aboBoNT-A 500U group spent more days with lower NPRS than their lowest baseline score, and with NPRS ≥2 points lower than their mean baseline NPRS at weeks 8 and 12 versus placebo (all p < .05; post-hoc). AboBoNT-A was well tolerated. Although the primary endpoint was unmet, other endpoints showed a nominal advantage for aboBoNT versus placebo for treatment of HV-related pain, particularly at week 12. Further clinical evaluation is needed to establish whether botulinum toxins represent a viable non-operative treatment option for HV-associated pain. PLAIN LANGUAGE SUMMARY: Hallux valgus is the medical name for a bunion, a foot deformity that can worsen over time. Patients with bunions experience pain and walking can become difficult, which can affect their quality of life. Foot support aids (e.g., braces, splints and inserts) are available, but surgery is the standard treatment. This study looked at how injections of a specific type of botulinum toxin, called abobotulinumtoxinA or "aboBoNT-A", into the foot may help to reduce pain in patients with bunions. The study included 186 patients aged 18 to 75 years who had not had surgery on their bunion. The researchers looked at how well the injections worked using scales that measure the pain levels the patient experienced. The main outcome was whether patients who had aboBoNT-A injections had less pain after 8 weeks than they did before treatment. The study included patients who were injected with saltwater (no treatment) to check that any treatment effect was real. Researchers also looked at the results after 12 weeks, as well as how many patients had less pain after treatment than before and how many days in a given week patients experienced less pain after treatment than they did before. There was no reduction in pain levels with aboBoNT-A injections after 8 weeks compared with no treatment. However, the other study outcomes suggested that aboBoNT-A resulted in a small benefit compared with no treatment, especially after 12 weeks. Further medical research is needed to establish whether botulinum toxins represent an alternative treatment to surgery for the pain associated with bunions.

Laser-Assisted Drug Delivery in the Treatment of Scars, Rhytids, and Melasma: A Comprehensive Review of the Literature

Although broad reviews on laser-assisted drug delivery (LADD) have been published in the past, an updated focused examination of its utility in the context of common, treatment-resistant, dermatologic conditions has not been published. This article reports a comprehensive scoping review of the potential benefits of LADD compared to laser or drug monotherapy for the treatment of 3 such conditions: scars, rhytids, and melasma. A PubMed (National Institutes of Health; Bethesda, MD) search was conducted for keywords including "laser-assisted drug delivery," "scar," "rhytid," and "melasma." Out-of-scope studies were excluded. To evaluate the efficacy of LADD for the treatment of scars, relevant articles were categorized by scar type: hypertrophic/keloid, atrophic, and hypopigmented. LADD, with both ablative and nonablative laser types, was studied in combination with corticosteroids, botulinum toxin-A (BTX-A), 5-fluorouracil, 5-aminolevulinic acid photodynamic therapy, stem cells, platelet-rich plasma, and prostaglandin analogs for the treatment of scars. Some randomized controlled trials demonstrated the efficacy of LADD, whereas others showed no significant differences in clinical outcomes but demonstrated reduced adverse effects. Regarding rhytids, laser treatment has been combined with various cosmeceuticals, including poly-L-lactic acid, topical retinaldehyde, and topical BTX-A. The studies reviewed supported the use of LADD with these drugs over monotherapy. Some studies showed that LADD was effective for the absorption of drugs such as poly-L-lactic acid and BTX-A which are often not effective topically. For melasma treatment, LADD with tranexamic acid and hydroquinone was superior in some studies, but not significantly different than monotherapy in other studies. LADD with certain drugs could be considered to treat scars, rhytids, and melasma.

LEVEL OF EVIDENCE: 5

Traditional Chinese medicine for hypertrophic scars—A review of the therapeutic methods and potential effects

Hypertrophic scar (HS) is a typical pathological response during skin injury, which can lead to pain, itching, and contracture in patients and even affect their physical and mental health. The complexity of the wound healing process leads to the formation of HS affected by many factors. Several treatments are available for HS, whereas some have more adverse reactions and can even cause new injuries with exacerbated scarring. Traditional Chinese Medicine (TCM) has a rich source, and most botanical drugs have few side effects, providing new ideas and methods for treating HS. This paper reviews the formation process of HS, the therapeutic strategy for HS, the research progress of TCM with its relevant mechanisms in the treatment of HS, and the related new drug delivery system of TCM, aiming to provide ideas for further research of botanical compounds in the treatment of HS, to promote the discovery of more efficient botanical candidates for the clinical treatment of HS, to accelerate the development of the new drug delivery system and the final clinical application, and at the same time, to promote the research on the anti-HS mechanism of multiherbal preparations (Fufang), to continuously improve the quality control and safety and effectiveness of anti-HS botanical drugs in clinical application.

A systematic review of randomised controlled trials investigating laser assisted drug delivery for the treatment of keloid and hypertrophic scars

The objective of this article is to study the clinical efficacy and adverse events of laser-assisted drug delivery in the treatment of hypertrophic and keloid scars. We searched the following databases up to 22 October 2020: the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials (Clinical Trials) in The Cochrane Library, MEDLINE, EMBASE, and reference lists of articles for randomised clinical trials (RCTs) of laser-assisted drug delivery for the treatment of hypertrophic and keloid scars. We also searched online trials registries for ongoing trials and contacted trial authors where appropriate. Our outcomes of interest were objective clinical evaluation of scars, participant satisfaction, and adverse effects of the treatments. Two authors independently extracted data and assessed trial quality using Cochrane Risk of Bias 2. Two authors independently abstracted data. We included 10 RCTs involving a total of 329 participants: six trials utilised parallel-arm RCTs whilst four employed split-scar design. Three trials had high risk of bias with the remaining seven rated as having some concerns. The interventions and outcomes were too varied to be combined statistically. High-quality randomised controlled trials assessing laser-assisted delivery for drugs in the context of hypertrophic and/or keloid scarring are needed. Studies with a larger number of participants, with longer follow-up times, and standardised evaluation of outcome and adverse effects are warranted.

Laser Resurfacing for the Management of Periorbital Scarring

Laser (light amplification by the stimulated emission of radiation) skin resurfacing is currently one of the most widely adopted technologies in facial rejuvenation. While most often used for aesthetic purposes, lasers also have applications in the management of scars. Since the introduction of the CO₂ laser for skin rejuvenation in the 1990s, the last three decades have seen significant growth in the number of laser devices available to the physician. More recently, promising alternatives to light-based resurfacing technologies have emerged that include radiofrequency and intense focused ultrasound. To help the physician navigate the most current laser technologies as they apply to periocular scars, this review discusses the available treatment modalities, pre-treatment assessment of periorbital scars, treatment selection, and reported outcomes and complications. The recommendations described herein are based on published literature and the authors' experience in an academic oculoplastics practice.