Intralesional cryotherapy for hypertrophic scars and keloids: a review

Emerging biomedical technologies for scarless wound healing

Complete wound healing without scar formation has attracted increasing attention, prompting the development of various strategies to address this challenge. In clinical settings, there is a growing preference for emerging biomedical technologies that effectively manage fibrosis following skin injury, as they provide high efficacy, cost-effectiveness, and minimal side effects compared to invasive and costly surgical techniques. This review gives an overview of the latest developments in advanced biomedical technologies for scarless wound management. We first introduce the wound healing process and key mechanisms involved in scar formation. Subsequently, we explore common strategies for wound treatment, including their fabrication methods, superior performance and the latest research developments in this field. We then shift our focus to emerging biomedical technologies for scarless wound healing, detailing the mechanism of action, unique properties, and advanced practical applications of various biomedical technology-based therapies, such as cell therapy, drug therapy, biomaterial therapy, and synergistic therapy. Finally, we critically assess the shortcomings and potential applications of these biomedical technologies and therapeutic methods in the realm of scar treatment.

Losartan in Situ Forming Gel as a New Treatment for Hypertrophic Scars

Hypertrophic scars are defined as visible lesions formed by excessive wound healing that cause cosmetic and, in some cases, functional challenges in patients. This study aimed to assess the efficacy of intralesional injections of losartan-loaded in situ forming gel and compare it with the common treatment (triamcinolone) in preventing scar formation. The formulation was prepared using a thermosensitive PLGA-PEG-PLGA triblock copolymer. Ear scar tissue in rabbits represented the hypertrophic scar, and the animals were treated with three treatments in three groups. Nine weeks following the single treatment, images of the scars were obtained and quantitatively analyzed using ImageJ and light microscopy was used to evaluate the fibroblast cell number, vascularization, inflammation and collagen deposition and fibrosis in H&E-stained sample tissue. According to the results based on the ImageJ and the Vancouver criteria, the losartan in situ forming gel (F-LG) indicated significantly higher improving effects on decreased vascularity and pigmentation in comparison with triamcinolone (F-TA) and placebo as a control (F-Ctl), although the effect F-LG was almost similar to F-TA on pliability and scar height, and they were better than the control. Histological findings showed F-LG and F-TA have less inflammatory and fibroblast cells compared to F-Ctl. Also, results indicated the dermal layers of the F-TA and F-LG groups' scar were thinner, and the deposition of collagens was reduced compared to the control. Consequently, F-LG was found to be an effective treatment in reducing scarring and promoting wound healing.No Level Assigned This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. 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 .

Post-surgical Hypertrophic Scar in a Patient With Unilateral Temporomandibular Joint Ankylosis

Wound healing is nature's response to injury. It is a complex and dynamic process involving multiple biological systems aimed at restoring the integrity of damaged tissue. The temporomandibular joint (TMJ) is a critical anatomical structure that facilitates jaw movement and function. TMJ ankylosis is a pathological condition characterized by fusion of the mandibular condyle to the glenoid fossa resulting in severe restriction in mouth opening and significantly reduced mandibular movements. This condition affects the patient's quality of life by deteriorating major functions such as mastication, speech, oral hygiene, breathing, facial growth, and esthetics. Gap arthroplasty is the mainstay of treatment. There are various surgical approaches to TMJ such as Al-Kayat Bramley, Popowich's modification, Blair's inverted hockey stick, Dingman's, Thoma's, endaural, postauricular, and rhytidectomy incisions. Wound healing in the TMJ region poses unique challenges due to its complex anatomy and the high level of mechanical stress it endures. Following trauma to TMJ, hematomas are organized by fibrous granulation tissues and mesenchymal stem cells are recruited from adjacent bone by cytokines and chemokines such as bone morphogenetic proteins, transforming growth factor-beta and stromal cell-derived factor 1. These recruited mesenchymal cells differentiate into osteoprogenitors and osteoblasts to form new bone and fibroblasts to form a scar. In humans, scarring is the final outcome of the wound healing process, which has evolved to rapidly repair injuries. Scarring from injuries, surgeries, and burns places a significant burden on the healthcare system. Patients with major scars, especially children and adolescents, often experience long-term functional and psychological issues. This article aims to present a case of post-surgical hypertrophic scar in a patient after gap arthroplasty through Al-Kayat Bramley incision and the role of a multi-professional team to treat such wounds.

Selective therapy (cryo or scalpel) combined with multimodal therapy for treating keloids

Background

Keloids are less responsive to any single treatment modality; hence, there is a need for combination therapy that can yield satisfactory outcomes.

Objective

The present study assessed efficacy and safety of combination therapy-surgical excision or cryotherapy and intralesional corticosteroids along with 5-fluorouracil [IL (S + 5-FU)] injection, followed by silicone gel sheet (SGS) under compression therapy in the treatment of keloids.

Materials and Methods

This was a retrospective, observational study comprising 21 clinically diagnosed keloid patients. All patients were treated with the stated combination therapy. Data about demographic, lesions, procedural characteristics, and treatment outcomes were reported.

Results

Of 21, 11 (52.4%) patients were treated with liquid nitrogen (LN2) cryotherapy, and 10 (47.6%) patients were treated with surgical excision. Mean age was 30.8 ± 7.6 (range: 14-44) years with slight male (52.4%) predominance. A mean surface area of keloid lesion was 96.8 ± 170.5 cm3. The most frequently involved site was auricle (8 [38.1%] patients). Patients received the following types of treatments: intralesional LN2 cryotherapy (6 [28.6%]), intralesional excisional surgery (6 [28.6%]), surface LN2 cryotherapy (5 [23.8%]), and extralesional excisional surgery (4 [19.0%]). Complications of recurrence (2 [9.5%]), secondary infections (2 [9.5%]), persistent postinflammatory hypopigmentation (1 [4.8%]), and atrophic scarring with postinflammatory hyperpigmentation (1 [4.8%]) were reported. After a study period of 2.5 years, 100% cure rate was achieved.

Conclusion

Combination therapy of surgical excision or cryotherapy and IL (S + 5-FU), followed by SGS under compression, was safe and effective in treating keloids.

Progress in the clinical treatment of keloids

Keloid is a pathological scar that is higher than the skin surface following skin damage. Its lesion range often extends beyond the original damage boundary and does not naturally subside over time. Its pathogenesis is very complex, currently the main causes include fibroblast excessive proliferation, collagen and extracellular matrix (Extracellular matrix, ECM) excessive deposition, excessive angiogenesis, and so on. The traditional treatment method primarily involves surgical intervention, but it is associated with a high recurrence rate post-surgery. Consequently, many treatment methods are derived according to the different clinical characteristics of keloid. This paper will review the therapeutic progress in recent years from surgical treatment, physiotherapy, drug therapy, and biological therapy, with the goal of offering valuable insights for the clinical treatment of keloids.

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.

Evidence-based management of keloids and hypertrophic scars in dermatology

While normal, controlled wound-healing results in scars that are nearly imperceptible, hypertrophic scars (HTS) and keloids are the result of an abnormal wound-healing process that can leave unsightly, difficult-to-treat lesions. While such scars are classically associated with surgical incisions, they may also result from burns or accidental trauma to the skin. Several different measures can be taken to prevent the formation of scars or treat those that have already formed. Prevention focuses on reducing inflammation during the wound-healing process, and minimizing tension in the lesion when appropriate. Treatments range from non-invasive modalities such as pressure therapy, topicals, and symptom management, to invasive methods such as injections, lasers, and even surgery. While some treatments, such as corticosteroid injections, have been used in the treatment of HTS and keloids for decades, other newer therapies have only been described in case reports or are still in early phases of clinical trials. Because optimal scar management will not be the same for every patient, further investigation of newer agents and methods is warranted and may benefit a great number of patients. This paper will review the evidence-based management of scars, including current widely used treatment options and promising newly emerging therapies.

Reducing Risks of Facial Scarring

Risk factors for the formation of facial scars include skin type, ethnicity, scar location, and certain medical conditions that contribute to poor or delayed healing. Risk of scar can be reduced with appropriate surgical planning, including proper placement and design of incisions, meticulous skin closure, aseptic technique, and wound care to improve healing. Common pathologic scars include hypertrophic scars and keloid scars, each of which has unique approaches to surgical revision and medical treatment due to their respective risks of recurrence. Topical scar therapies, medical therapies, and surgical revision techniques for improvement in final scar appearance are discussed.

Hypertrophic Scars and Keloids: Advances in Treatment and Review of Established Therapies

Hypertrophic scars and keloids can have significant detrimental effects on patients both psychosocially and functionally. A careful identification of patient risk factors and a comprehensive management plan are necessary to optimize outcomes. Patients with a history of dystrophic scarring should avoid unnecessary procedures and enhance the wound-healing process using various preventive strategies. As there is no single, fully efficacious treatment modality, prevention remains the best approach in reducing aberrant scar formation. When prevention therapies fail, keloids have been shown to be respond to a variety of therapies including topical and injectable corticosteroids, 5-fluorouracil, radiotherapy, lasers, and surgical excision, all with varying efficacies. As such, management should be tailored to the individual patient's risk factors with the use of combination therapies to reduce recurrence rates. Still, keloid and hypertrophic scar therapies are widely diverse with novel treatment modalities providing alternatives for recurring lesions. Laser-assisted drug delivery, skin priming, and novel topical therapies may provide alternative options for the management of hypertrophic scars and keloids.

Relevant Dermatoses Among U.S. Military Service Members: An Operational Review of Management Strategies and Telemedicine Utilization

Despite skin being the largest and most exposed organ of the human body, skin issues can be challenging to diagnose in deployed military service members. Common reasons deployed soldiers seek dermatological evaluation include infections, inflammatory skin conditions, and skin growth. Due to limited access to specialized care in deployed settings, dermatological conditions are undertreated and underdiagnosed. As a result, dermatological conditions are a leading contributor to decreased combat effectiveness among deployed medical forces. To lessen the burden of dermatological diseases, military providers should promptly identify operational skin diseases and alleviate modifiable barriers faced by service members. In a post-pandemic era with novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and monkeypox infections, the duty to effectively treat operational skin lesions is ever important. The need for military dermatologists continues to rise as the global landscape continues to evolve with unprecedented infections and increased bioterrorism threats. Teledermatology offers many solutions to mitigate the high demand for dermatologists during pandemics. Dermatological consultations account for the highest number of telemedicine visits in the US Military Health System (MHS). As such, increased utilization of teledermatology will reduce infection-related dermatological sequelae and prevent the medical evacuation of service members from military operations. This review collates and categorizes relevant dermatological conditions encountered among deployed personnel. This report outlines the standard of care and modified treatments recommended according to potential barriers faced in operational settings.

Keloid Therapy: A Neoteric Comparative Study

BACKGROUND

Keloids are considered disorders of fibroproliferation characterized by accumulation of collagen fibers in hypodermis and dermis, caused by inflammation, surgery, and trauma.

OBJECTIVES

The main goal of the study was to approach a better modality for the treatment of keloids by comparing the effects and the side effects of intralesional cryotherapy and intralesional injection of bleomycin.

METHODS

This interventional, comparative clinical trial was conducted on 60 cases and were divided equally into the group (A) combined group where who were subjected to intralesional bleomycin followed by cryotherapy in the same session, group (B) who were subjected to intralesional injection of bleomycin, and group (C) intralesional cryotherapy. All cases were subjected to clinical examination, complete history taking, dermatological examination, examination, and evaluation of scar lesion using the Vancouver scar scale.

RESULTS

There was a statistically significant decrease in pliability among the combined group. Also, pliability decreased in the bleomycin group and cryotherapy, but this decrease wasn't statistically significant. Our results revealed that there was a statistically significant decrease in lesion height among all the studied groups, but the decrease was more among the combined group.

CONCLUSION

Intralesional cryotherapy was effective as Intralesional bleomycin. Combined therapy was a valid and more effective technique with few adverse effects than either alone for keloids as it achieved a decrease in volumes of scars or accompanied symptoms.

Israeli Innovations in the Field of Plastic Surgery

Numerous innovations within the field of plastic surgery have been developed in Israel over the last few decades. Many of these therapeutic devices and techniques have been established globally with demonstrable efficacy and respectable safety profiles. This article offers an overview of recent Israeli cutting-edge medical therapeutic solutions contributing to the global practice of plastic surgery.

The Most Current Algorithms for the Treatment and Prevention of Hypertrophic Scars and Keloids: A 2020 Update of the Algorithms Published 10 Years Ago

BACKGROUND

In 2010, this Journal published my comprehensive review of the literature on hypertrophic scars and keloids. In that article, I presented evidence-based algorithms for the prevention and treatment of these refractory pathologic scars. In the ensuing decade, substantial progress has been made in the field, including many new randomized controlled trials. To reflect this, I have updated my review.

METHODS

All studies were evaluated for methodologic quality. Baseline characteristics of patients were extracted along with the interventions and their outcomes. Systematic reviews, meta-analyses, and comprehensive reviews were included if available.

RESULTS

Risk factors that promote hypertrophic scar and keloid growth include local factors (tension on the wound/scar), systemic factors (e.g., hypertension), genetic factors (e.g., single-nucleotide polymorphisms), and lifestyle factors. Treatment of hypertrophic scars depends on scar contracture severity: if severe, surgery is the first choice. If not, conservative therapies are indicated. Keloid treatment depends on whether they are small and single or large and multiple. Small and single keloids can be treated radically by surgery with adjuvant therapy (e.g., radiotherapy) or multimodal conservative therapy. For large and multiple keloids, volume- and number-reducing surgery is a choice. Regardless of the treatment(s), patients should be followed up over the long term. Conservative therapies, including gel sheets, tape fixation, topical and injected external agents, oral agents, and makeup therapy, should be administered on a case-by-case basis.

CONCLUSIONS

Randomized controlled trials on pathologic scar management have increased markedly over the past decade. Although these studies suffer from various limitations, they have greatly improved hypertrophic scar and keloid management. Future high-quality trials are likely to improve the current hypertrophic scar and keloid treatment algorithms further.

Intralesional Agents in Dermatology: Pros and Cons

Since introduced in 1961, intralesional (IL) agent has become an essential part of the dermatological practice. The term IL referred to the direct delivery of agent percutaneously into skin lesions. This therapeutic approach is relatively safe, easy to perform and applicable for a broad range of dermatological conditions. On the other hand, immediate side effects, including pain during administration, bleeding, high risk of infection and allergic reaction, and subsequent side effects involving skin changes such as atrophy, telangiectasia, pigmentary changes, and striae are usually associated with this modality. This review paper highlights the pros and cons of IL agents in modern dermatology practice.

Current Advances in Hypertrophic Scar and Keloid Management

Hypertrophic scars and keloids are caused by excessive tissue response to dermal injury due to local fibroblast proliferation and collagen overproduction. This response occurs because of pathologic wound healing due to dysregulation in the inflammatory, proliferative, and/or remodeling phase. Patients with hypertrophic scars or keloids report reduced quality of life, physical status, and psychological health. Hypertrophic scars or keloids will develop in 30 to 90% of individuals, and despite their prevalence, treatment remains a challenge. Of the treatments currently available for hypertrophic scars and keloids few have been adequately supported by studies with appropriate experimental design. Here, we aim to review the available literature to provide up-to-date information on the etiology, epidemiology, histology, pathophysiology, prevention, and management options available for the treatment of hypertrophic scars and keloids and highlight areas where further research is required.

Treatment of keloids and hypertrophic scars. Position statement of the Brazilian expert group GREMCIQ

Keloids (K) and hypertrophic scars (HS) are abnormal responses to wound healing that occur as the result of dermal inflammation. Despite the advances on their treatment, many patients still suffer from the negative effects of excessive scarring; its approach is impaired by the lack of objective data on different treatments and the large genetic variability among patients and the difficulties in producing multicentre studies. Their incidence among the Brazilian population is high, as the result of an admixture of Amerindians, Europeans and Africans ancestral roots. With the aim of producing multicentre studies on K and HS, a panel of senior Brazilian dermatologists focused on their treatment was invited to contribute with the K and HS Treatment Brazilian Guidelines. In the first part of this study, different treatment modalities for keloids and HS are fully reviewed by the panel. The second part of the study presents a consensus recommendation of treatment for different types of lesions. More than a literature review, this article aims to show the pitfalls and pearls of each therapeutic option, as well as a therapeutic approach by the Panel of Experts on keloids and Scars on a highly mixed population, providing simple guidelines.

Subcutaneous emphysema after intralesional cryotherapy: An unusual complication

BACKGROUND

Intralesional cryotherapy (ILC) is a safe and well tolerated by the patient. Subcutaneous emphysema (SE) cases after spray and contact cryotherapy have been described; however, this complication has not been previously reported after ILC.

AIM

Our aim is to discuss the possible causes of SE development after ILC.

METHOD

We present a young patient that developed SE after ILC applying by insertion of an open-ended needle to the tip of the cryotherapy gun.

RESULTS

The development of SE following ILC may have been caused by inward clefting from the ear hole, the usage of an open-ended needle and a lack of safety system.

CONCLUSION

It will be safer to apply special methods involving the usage of sealed distal type to prevent SE development.

A novel experimental model for studying efficacy of cryosurgery in keloids

BACKGROUND

Intralesional cryosurgery is effective in the treatment of keloids; however, clinical studies have presented diversified results.

OBJECTIVE

A novel, reproducible model for biophysical studies on intralesional cryosurgery of keloids is presented.

METHODS

Triplicate studies with a cryosurgical needle on 37°C-heated potatoes, which exhibit identical specific heat and similar heat conductivity with human skin, were performed.

RESULTS

No complete potato freezing resulted through a cryosurgical needle. The limited tissue damage achieved had a double concave form. The needle induced lower temperature and stronger tissue damage at the distal exit than the proximal entrance site. The concave form of tissue damage flattened with time at the area under the needle. Needle freezing with puncture distances of 0.5, 1.0 and 1.5 cm from the potato surface only revealed freezing temperatures within the 0.5 cm range. At any needle depth, tissue damage was detected at only an area to about 1 cm under the needle.

CONCLUSION

Clinical extrapolation of these experimental findings indicates a proper needle positioning towards the keloid basis, shows keloid volume freezing limitations by a single needle and corroborates the observations of minor epidermal and deep dermal damage induced by intralesional cryosurgery.

Keloids: A Review of Etiology, Prevention, and Treatment

Keloids are abnormal scars that cause significant emotional and physical distress in patients when inadequately treated. Keloid formation is theorized to occur as a result of an imbalance between an increased synthesis of collagen and extracellular matrix and decreased degradation of these products. Inflammatory mediators- namely, transforming growth factor beta-have been proposed to influence the dysregulation of collagen remodeling in the scar healing process. Though limited, current knowledge of keloid pathophysiology has guided clinicians to explore novel therapies for keloid prevention and treatment. In addition to conducting research refining the use of common therapies, such as steroids and radiation, clinicians have evaluated the potential of anti-inflammatory and chemotherapeutic molecules to suppress keloid recurrence. Procedural focused therapies, such as cryotherapy and lasers, have also found a role in reducing keloid symptomatology. The purpose of this report is to examine the current literature and review the mechanisms of action, efficacy, and side effects of different keloid therapies. Despite the growing literature investigating reliable methods for keloid management, there are no standardized guidelines or treatment protocols supported by academic governing bodies. Stronger evidence with high-fidelity randomized clinical trials will be needed to determine the optimal therapy regimens for keloids.

Keloids: Current and emerging therapies

Keloids are pathological scars that grow over time and extend beyond the initial site of injury after impaired wound healing. These scars frequently recur and rarely regress. They are aesthetically disfiguring, can cause pain, itching, discomfort as well as psychological stress, often affecting quality of life. Many treatment modalities, including surgical and non-surgical, have been explored and have been reported to be beneficial; however, none have been absolutely satisfactory or optimal for the treatment of all keloid subtypes to date. This poses a major challenge to clinicians. Often, a combinational therapeutic approach appears to offer the best results with higher patient satisfaction compared to monotherapy. The aetiopathogenesis of keloids is not fully elucidated; however, with recent advances in molecular biology and genetics, insight is being gained on the complex process of scar formation and hence new therapeutic and management options for keloids. In this paper, we explore the literature and summarise the general concepts surrounding keloid development and review both current (corticosteroids, surgical excision, silicone-based products, pressure therapy, radiotherapy, cryotherapy, laser therapy, imiquimod and 5-fluorouracil) and emerging (stem cell therapy, mitomycin C, verapamil, interferons, bleomycin, botulinum toxin type A and angiotensin-converting enzyme inhibitors) treatments. Increased knowledge and understanding in this area may potentially lead to the discovery and development of novel therapeutic options that are more efficacious for all keloid types.

LAY SUMMARY

Keloids are problematic scars that are difficult to treat and manage. The aetiopathogenesis of keloids is not clear; however, recent advances in molecular biology and genetics are beginning to shed light on the underlying mechanisms implicated in keloid scar formation which will hopefully lead to the development of treatment options for all keloid types. This review summarises current and emerging therapies.

Z-plasty and Postoperative Radiotherapy for Upper-arm Keloids: An Analysis of 38 Patients

Therapies for upper arm keloids include surgical excision followed by postoperative radiotherapy, silicone tape stabilization, and steroid plaster. However, a universally accepted therapeutic strategy for upper-arm keloids is lacking.

Intralesional cryotherapy for hypertrophic scars and keloids: a review

Introduction

Hypertrophic and keloid scarring remain notoriously troublesome for patients to tolerate and frustratingly difficult for clinicians to treat. Many different treatment modalities exist, signifying the failure of any method to achieve consistently excellent results. Intralesional cryotherapy is a relatively recent development that uses a double lumen needle, placed through the core of a keloid or hypertrophic scar, to deliver nitrogen vapour, which freezes the scar from its core, outwards.

Methods

This article provides a comprehensive review of the literature on intralesional cryotherapy for hypertrophic scars and keloids. A systematic review or meta-analysis was not possible, since the existing articles did not permit this.

Results

A search of English language, peer-reviewed literature was carried out. The evidence base was found to be low (level 4). In addition, much of the published evidence comes from a very few groups. Despite this, consistent findings from case series suggest that the technique is safe and achieves good scar reduction with very few treatments. Adverse effects include depigmentation, recurrence and pain. Pain and recurrence appear to be uncommon and depigmentation may be temporary.

Discussion

Well-constructed, prospectively recruited comparative trials are absent from the literature. These are strongly encouraged, in order to strengthen general confidence in this technique and in the repeatability of outcomes reported thus far.