Management of Tracheostomy Scar by Autologous Fat Transplantation: A Minimally Invasive New Approach

Effectiveness of Autologous Fat Grafting in the Treatment of Scars: A Systematic Review and Meta-Analysis

BACKGROUND

Autologous fat transfer (AFT) has been proposed as a possible treatment for scar tissue and its associated symptoms. Its effectiveness's evidence is yet unidentified though. The aim of this meta-analysis is to evaluate the currently available evidence on the efficacy and safety of autologous fat transfer in treating post-burn and post-traumatic scars using a validated scar measurement tool.

METHODS

This study performed a systematic literature review in November 2023 using the following electronic databases: MEDLINE, SCOPUS, Directory of Open Access Journals (DOAJ), PUBMED, and Google Scholar. The following key terms were included: (Fat grafting OR Autologous fat transfer) AND (body scars OR body burns OR body wounds) AND (Efficacy OR Safety OR satisfaction). We evaluated articles according to predefined quality criteria. The following data were included during the extraction period: patient demographics, indications for AFT, the number of AFT sessions, follow-up periods, and changes in the Patient and Observer Scar Assessment Scale (POSAS) scores, which contain both the patient and observer components.

RESULTS

This study included 1326 patients and 23 published articles. A total of 14 prospective studies, 7 retrospective studies, and 2 Randomized clinical trials studies were evaluated. These 23 articles came from diverse global locations; the earliest was published in 1992, and the most recently published in 2022.

CONCLUSION

Our findings demonstrated significant enhancements in scar characteristics from both patient and observer perspectives. Overall, AFT holds promise as a valuable treatment option for scar-related conditions as it enhances scar quality ,contributing to improved patient outcomes and satisfaction.

LEVEL OF EVIDENCE III

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 Table of Contents or the online Instructions to Authors www.springer.com/00266.

Investigating the Efficacy of Modified Lipoaspirate Grafting to Improve the Appearance of Atrophic Acne Scars: A Pilot Study

BACKGROUND

Processed lipoaspirate grafting describes several techniques theorized to leverage the inflammatory and regenerative capacities of mechanically processed adipocytes to rejuvenate and correct skin pathology. Although lipoaspirate grafting is typically leveraged to fill visible defects such as depressed scars and dermal lines, additional fat processing allows grafts to stimulate mechanisms of wound healing, including the promotion of fibroblast activation, neovascularization, and neocollagenesis.

OBJECTIVES

This study intends to assess the efficacy and tolerability of processed lipoaspirate grafting monotherapy to improve the clinical appearance of atrophic acne scars.

METHODS

Patients underwent a single autologous processed lipoaspirate grafting procedure at the site of atrophic acne scars. Objective and subjective scar analysis was performed at 3 and 6 months posttreatment. Scars were assessed with standard photography, topographic analysis, and noninvasive skin measurements. In addition, microbiopsies were obtained before and after treatment to assess histological or genetic changes. Clinical improvement was assessed with patient and clinician Global Aesthetic Improvement Scales (GAIS) and blinded photographic evaluation.

RESULTS

Ten patients between ages 18 and 60 completed the study. Clinical evaluation demonstrated that fat grafting improved the appearance of atrophic acne scars. Clinician GAIS and patient GAIS scores showed clinical improvement at both 3- and 6-month follow-up compared with baseline (P < .05). Blinded clinician GAIS scores also showed statistically significant improvement when clinicians compared clinical photographs taken at 6-month follow-up to baseline (P < .0001). The attenuation coefficient increased at 6-month follow-up, suggesting collagen remodeling and reorganization over the study period. Patients experienced anticipated posttreatment symptoms including transient erythema and edema; however, no unexpected adverse events were reported.

CONCLUSIONS

Micronized lipoaspirate injection is a viable and effective option to improve the appearance of facial acne scarring. Favorable improvements in atrophic acne scarring were captured by objective analysis of skin ultrastructure as well as improvement in subjective assessments of scarring.

LEVEL OF EVIDENCE: 4

Stromal vascular fraction-enriched fat grafting as treatment of adherent scars: study design of a non-randomized early phase trial

Background

In the last decades, autologous fat grafting has been used to treat adherent dermal scars. The observed regenerative and scar-reducing properties have been mainly ascribed to the tissue-derived stromal vascular fraction (tSVF) in adipose tissue. Adipose tissue’s components augment local angiogenesis and mitosis in resident tissue cells. Moreover, it promotes collagen remodeling. We hypothesize that tSVF potentiates fat grafting-based treatment of adherent scars. Therefore, this study aims to investigate the effect of tSVF-enriched fat grafting on scar pliability over a 12-month period.

Methods and design

A clinical multicenter non-randomized early phase trial will be conducted in two dedicated Dutch Burn Centers (Red Cross Hospital, Beverwijk, and Martini Hospital, Groningen). After informed consent, 46 patients (≥18 years) with adherent scars caused by burns, necrotic fasciitis, or degloving injury who have an indication for fat grafting will receive a sub-cicatricic tSVF-enriched fat graft. The primary outcome is the change in scar pliability measured by the Cutometer between pre- and 12 months post-grafting. Secondary outcomes are scar pliability (after 3 months), scar erythema, and melanin measured by the DSM II Colormeter; scar quality assessed by the patient and observer scales of the Patient and Observer Scar Assessment Scale (POSAS) 2.0; and histological analysis of scar biopsies (voluntary) and tSVF quality and composition. This study has been approved by the Dutch Central Committee for Clinical Research (CCMO), NL72094.000.20.

Conclusion

This study will test the clinical efficacy of tSVF-enriched fat grafting to treat dermal scars while the underlying working mechanism will be probed into too.

Trial registration

Dutch Trial Register NL 8461. Registered on 16 March 2020

Evaluation of post-tracheostomy scars and their impact on persons' quality of life: A case-control study

Tracheostomy is one of the more commonly performed procedures in critically ill patients under mechanical ventilation. Postoperative scarring is one of the bothersome sequelae of tracheostomies. Scars distort physical appearance, especially when found on the head and neck, which could have a negative impact on quality of life. The aim of this study was to evaluate and assess the impact of post-tracheostomy scars on quality of life according to the tracheostomy method. A prospective, single-center, observational, case-control study was conducted. One hundred fifty-six persons with a post-tracheostomy surgical scar for more than four months were observed using the Patient and Observer Scar Assessment Scale and Dermatology Life Quality Index questionnaire. Persons were divided into two groups depending on the method of tracheostomy, and the duration of the cannulated period was considered in both groups. Statistical analyses were performed using SPSS ver. 16.0 (SPSS Inc., Chicago, IL, USA), and P values of <0.05 were considered significant. The patients who had a tracheostomic tube cannulation period of fewer than 15 days had better cosmetic results than those who had tracheostomic tubes for more than 15 days, regardless of the tracheostomy method: 6.64 ± 0.082 versus 16.15 ± 0.096 (P < 0.001) in the surgical tracheostomy group and 7.26 ± 0.211 versus 14.17 ± 0.379 (P < 0.05) in the percutaneous dilatational group. The Dermatology Life Quality Index scores had a mean value of 0.6 ± 0.01, which means that post-tracheostomy scarring in the present study had no effect on the person's quality of life. The aesthetic outcomes of post-tracheostomy scars after the open surgical tracheostomy technique did not significantly differ from those of the percutaneous dilatational technique in the present study. Persons with a long duration of tracheostomic tube ventilation showed worse aesthetic outcomes than those with short-term tracheostomic cannulation, which was not dependent on the tracheostomy technique. The Dermatology Life Quality Index showed that post-ttracheostomy scarring in the present study had no effect on the person's quality of life.

Effectiveness of Autologous Fat Transfer in the Treatment of Scar-Related Conditions: A Systematic Review and Meta-analysis

BACKGROUND AND AIM

Autologous fat transfer (AFT) has been introduced as a potential treatment option for scar-tissue and its related symptoms. However, the scientific evidence for its effectiveness remains unclear. This meta-analysis aims to evaluate the available evidence regarding the effectiveness of autologous fat transfer for the treatment of scar-tissue and its related conditions.

METHODS

PubMed/Medline database was queried from its inception till the end of November 2021. All the relevant studies assessing the effect of autologous fat transfer in the treatment of scar-related conditions were pooled in using a random-effects model.

RESULTS

9 studies (n=179) were included in the meta-analysis. Pooled analysis demonstrates significant improvement in all subscales of the POSAS patient score with most prominent in color 2.4 points (95% CI 1.78-3.041), stiffness 2.9 points (95% CI 2.33-3.45), irregularity 2.2 points (95% CI 1.093-3.297) and thickness 1.8 points (95% CI 0.804-2.719), respectively. Pain and itch improved relatively lesser, 1.3 points (95% CI 0.958-1.674) and 0.6 points (95% CI 0.169-1.215), respectively. The POSAS observer scale showed a relatively lower improvement with the least in vascularity 0.5 points (95% CI 0.098-0.96), pigmentation 0.8 points (95% CI 0.391-1.276) and surface area 0.8 points (95% CI 0.34-1.25). Thickness improved by 1.4 points (95% CI 0.582-2.3), relief 1.0 points (95% CI 0.461-1.545) and pliability 1.5 points (95% CI 1.039-2.036).

CONCLUSION

Our findings demonstrate that autologous fat transfer (AFT) is a promising treatment for scar-related conditions as it provides beneficial results in the scar quality. Future research should focus on the long-term effects of AFT and high-level evidence studies such as, randomized controlled trials (RCTs) and cohort studies are required.

LEVEL OF EVIDENCE III

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 .

Autologous Lipofilling Improves Clinical Outcome in Patients With Symptomatic Dermal Scars Through Induction of a Pro-Regenerative Immune Response

BACKGROUND

Autologous lipofilling is an emerging procedure to treat and possibly reverse dermal scars and to reduce scar-related pain, but its efficacy and mechanisms are poorly understood.

OBJECTIVES

The aim of this study was to test the hypothesis that repeated lipografts reverse dermal scars by reinitiation of wound healing.

METHODS

In a prospective, non-placebo-controlled clinical study, 27 adult patients with symptomatic scars were given 2 lipofilling treatments at 3-month intervals. As primary outcome, clinical effects were measured with the Patient and Observer Scar Assessment Scale (POSAS). Scar biopsies were taken before and after treatments to assess scar remodeling at a cellular level.

RESULTS

Twenty patients completed the study. Patients' scars improved after lipofilling. The total POSAS scores (combined patient and observer scores) decreased from 73.2  [14.7] points (mean [standard deviation]) pretreatment to 46.1 [14.0] and 32.3 [13.2] points after the first and second lipofilling treatment, respectively. Patient POSAS scores decreased from 37.3 [8.8] points to 27.2 [11.3] and 21.1 [11.4] points, whereas observer POSAS scores decreased from 35.9 [9.5] points to 18.9 [6.0] and 11.3 [4.5] points after the first and second treatment, respectively. After each lipofilling treatment, T lymphocytes, mast cells, and M2 macrophages had invaded scar tissue and were associated with increased vascularization. In addition, the scar-associated epidermis showed an increase in epidermal cell proliferation to levels similar to that normal in skin. Moreover, lipofilling treatment caused normalization of the extracellular matrix organization towards that of normal skin.

CONCLUSIONS

Autologous lipofilling improves the clinical outcome of dermal scars through the induction of a pro-regenerative immune response, increased vascularization, and epidermal proliferation and remodeling of scar tissue extracellular matrix.

LEVEL OF EVIDENCE: 4

A critical review on the potential role of adipose-derived stem cells for future treatment of hypertrophic scars

INTRODUCTION

Adipose-derived stem cells (ASCs) have recently gained researchers' interest as a solution to various diseases and conditions, including hypertrophic scar. This literature review aims to elucidate ASCs as a potential solution to alleviate hypertrophic scar in human subjects.

METHODS

Literature search was done in databases which includes PubMed, MEDLINE, and ProQuest using terms 'adipose derived stem cells', 'adipose cells', 'fat graft', 'fat grafting', 'autologous fat graft', 'fat injection', 'lipofilling', 'scar management', 'scar treatment', 'burn scar', and 'wound management'. The included articles which were published during year 2000-November 2020 must describe the use of ASCs or fat grafting or lipofilling as an attempt to alleviate hypertrophic scar.

REMARKS

Clinically, ASCs improve hypertrophic scars in terms of scar color, elasticity, texture, thickness, and size. Histologically, ASCs promotes healthy tissue regeneration, reduction in fibroblasts, and reorganisation of collagen, resembling those of normal skin. In terms of molecular aspects, ASCs alleviates hypertrophic scars through direct differentiation and paracrine mechanisms.

CONCLUSION

Adipose-derived stem cells, emerge to be a potential solution for alleviating hypertrophic scar, as demonstrated in various studies. However, there has been no studies conducted in human subjects to investigate the effect of ASCs on hypertrophic scar.

A new surgical approach in the treatment of tracheostomy scars

The tracheostomy procedure presents some long term complications such as the depressed scar. It can be responsible for a tracheal tug, invaginated scar, inaesthetic scar or all of them. No consensus has emerged in the treatment of this type of pathological scarring. We want to propose a new surgical approach to correct all these three pathological scarring mechanism by a subcutaneous flap in single operation.

A Systematic Review of Autologous Fat Grafting in the Treatment of Acute and Chronic Cutaneous Wounds

There is a growing interest in the regenerative potential of autologous fat. Adipose-derived stem cells, within the stromal vascular fraction of lipoaspirate samples, demonstrate anti-inflammatory, immunomodulatory, and angiogenic properties. This systematic review aimed to determine the efficacy and safety of autologous fat therapies for wound healing, with an evaluation of the quality of evidence provided by the literature.

Regenerative medicine approaches for the management of respiratory tract fistulas

Respiratory tract fistulas (or fistulae) are abnormal communications between the respiratory system and the digestive tract or the adjacent organs. The origin can be congenital or, more frequently, iatrogenic and the clinical presentation is heterogeneous. Respiratory tract fistulas can lead to severely reduced health-related quality of life and short survival. Therapy mainly relies on endoscopic surgical interventions but patients often require prolonged hospitalization and may develop complications. Therefore, more conservative regenerative medicine approaches, mainly based on lipotransfer, have also been investigated. Adipose tissue can be delivered either as unprocessed tissue, or after enzymatic treatment to derive the cellular stromal vascular fraction. In the current narrative review, we provide an overview of the main tissue/cell-based clinical studies for the management of various types of respiratory tract fistulas or injuries. Clinical experience is limited, as most of the studies were performed on a small number of patients. Albeit a conclusive proof of efficacy cannot be drawn, the reviewed studies suggest that grafting of adipose tissue-derived material may represent a minimally invasive and conservative treatment option, alternative to more aggressive surgical procedures. Knowledge on safety and tolerability acquired in prior studies can lead to the design of future, larger trials that may exploit innovative procedures for tissue processing to further improve the clinical outcome.

Autologous fat transfer to treat fibrosis and scar-related conditions: A systematic review and meta-analysis

BACKGROUND

Autologous fat transfer (AFT), also known as lipofilling, has been demonstrated to be more than just a filler. Through both mechanical dissection and local tissue remodelling mediated by stem cells, it is thought to improve scar quality, function and even pain. This paper aims to investigate the evidence regarding its safety and effectiveness for treating fibrosis and scar-related conditions.

METHODS

A literature search was performed in PubMed, Embase and the Cochrane Library to identify relevant studies. Extensive data extraction and standardization allowed conducting a meta-analysis.

RESULTS

Forty-five studies (3033 patients) provided sufficient data for meta-analysis. The AFT treatment resulted in significant increase in satisfaction scores of both patient and surgeon (p  =  0.001). Furthermore, a significant overall scar improvement was also found in the evaluation using the Patient and Observer Scar Assessment Scale, with the most notable effect in the scar stiffness (p<0.001) and pliability (p  =  0.004). In patients with severe pain, AFT resulted in a significant pain reduction of 3.7 points on the Visual Analogue Scale (p<0.001). Last, but not the least, the evidence suggests a significant recovery of radiotherapy-induced tissue damage (p  =  0.003) and function (p  =  0.012). On average, 1.4 procedures were required to achieve the desired result. Minor complications occurred in 4.8% of the procedures.

CONCLUSIONS

AFT is a promising treatment for fibrosis and scar-related conditions. Future research should focus on determining the long-term effects of AFT on fibrosis, pain and function. In addition, it would be crucial to quantify the mechanical and regenerative properties of fat as well as the effect of added supplements or stem cells.

The Impact of Lidocaine on Adipose-Derived Stem Cells in Human Adipose Tissue Harvested by Liposuction and Used for Lipotransfer

The local anesthetic lidocaine, which has been used extensively during liposuction, has been reported to have cytotoxic effects and therefore would be unsuitable for use in autologous lipotransfer. We evaluated the effect of lidocaine on the distribution, number, and viability of adipose-derived stem cells (ASCs), preadipocytes, mature adipocytes, and leukocytes in the fatty and fluid portion of the lipoaspirate using antibody staining and flow cytometry analyses. Adipose tissue was harvested from 11 female patients who underwent liposuction. Abdominal subcutaneous fat tissue was infiltrated with tumescent local anesthesia, containing lidocaine on the left and lacking lidocaine on the right side of the abdomen, and harvested subsequently. Lidocaine had no influence on the relative distribution, cell number, or viability of ASCs, preadipocytes, mature adipocytes, or leukocytes in the stromal-vascular fraction. Assessing the fatty and fluid portions of the lipoaspirate, the fatty portions contained significantly more ASCs (p < 0.05), stem cells expressing the preadipocyte marker Pref-1 (p < 0.01 w/lidocaine, p < 0.05 w/o lidocaine), and mature adipocytes (p < 0.05 w/lidocaine, p < 0.01 w/o lidocaine) than the fluid portions. Only the fatty portion should be used for transplantation. This study found no evidence that would contraindicate the use of lidocaine in lipotransfer. Limitations of the study include the small sample size and the inclusion of only female patients.

Autologous adipose tissue grafting for the management of the painful scar

BACKGROUND AIMS

There is currently no definitive treatment for the painful scar. Autologous adipose tissue grafting (AATG) as a treatment option for scars has become increasingly popular and there is now an abundance of evidence in the literature that supports its application. Some studies suggest that human adipose tissue is a rich source of multipotent mesenchymal stromal cells. To our knowledge, there is currently no systematic literature review to date that examines the effectiveness of AATG for reducing pain in scars. Our novel systematic review aims to examine clinical studies on the use of AATG in the treatment of the painful scar.

METHODS

A literature search was performed using the following databases: PubMed, Cumulative Index to Nursing and Allied Health Literature, Web of Science, Medline, Cochrane library and Embase. The following key words and search terms were used: adipose stem cells, scar, pain, autologous fat grafting, scar management and neuropathic pain. Human interventional studies using autologous adipose tissue grafting for the treatment of painful scars including case series, case-control, cohort studies and randomized controlled trials were reviewed.

RESULTS

A total of 387 studies were found and 18 studies from January 1990 to January 2019 were identified as relevant for the purpose of this systematic review. Two studies were evidence level V, seven were evidence level IV, six were evidence level III, two were evidence level II and one was level I. A total of 337 scars were assessed in 288 patients for improvement in pain after scar treatment using adipose tissue grafting. An improvement in the analgesic effect was recorded in 12 of the 18 studies with adipose tissue grafting. A total of 233 of the 288 treated subjects responded with reduction in pain, whereas the rest did not. We carried out a pooled analysis of the studies and observed an odds ratio of 3.94 (P = 0.00001) when comparing pain reduction to no change in pain.

CONCLUSIONS

We conclude that AATG is a promising and safe modality for the treatment of the painful scar. There is an abundance of low-level evidence to support its use as an alternative treatment but there is a lack of high-level evidence at present to support its standard use. Future long-term randomized controlled trials with analgesic scores as the primary outcome measures are required to assess long-term efficacy.

Adipose-Derived Tissue in the Treatment of Dermal Fibrosis: Antifibrotic Effects of Adipose-Derived Stem Cells

Treatment of hypertrophic scars and other fibrotic skin conditions with autologous fat injections shows promising clinical results; however, the underlying mechanisms of its antifibrotic action have not been comprehensively studied. Adipose-derived stem cells, or stromal cell-derived factors, inherent components of the transplanted fat tissue, seem to be responsible for its therapeutic effects on difficult scars. The mechanisms by which this therapeutic effect takes place are diverse and are mostly mediated by paracrine signaling, which switches on various antifibrotic molecular pathways, modulates the activity of the central profibrotic transforming growth factor β/Smad pathway, and normalizes functioning of fibroblasts and keratinocytes in the recipient site. Direct cell-to-cell communications and differentiation of cell types may also play a positive role in scar treatment, even though they have not been extensively studied in this context. A more thorough understanding of the fat tissue antifibrotic mechanisms of action will turn this treatment from an anecdotal remedy to a more controlled, timely administered technology.

Tracheostomy scar management by repositioning platysma muscle and applying an acellular dermal substitute

BACKGROUND

A depressed tracheostomy scar can be esthetically unacceptable. We describe a new technique for managing tracheostomy scars using platysma muscle repositioning and the application of an acellular dermal substitute.

METHODS

Seventeen patients with depressed tracheostomy scars were identified for scar management. The time between tracheostomy tube removal and scar management was 29 months. Before and after the surgery, the scar was rated using the Vancouver Scar Scale (VSS).

RESULTS

After surgery, tracheal tug was eliminated in all patients and the appearance of the scar was much improved. The mean total VSS score improved from 8.265 to 2.324 (P < 0.0001). The follow-up period was 33.3 months.

CONCLUSIONS

The management of tracheostomy scars by repositioning platysma muscle and applying an acellular dermal substitute is simple and efficient. The technique recovers the lost deep tissue volume, corrects tracheal skin tug, and enables tension-free skin closure to restore the normal contour of the neck.

Therapeutic Effects of Human Adipose-Derived Products on Impaired Wound Healing in Irradiated Tissue

BACKGROUND

Clinical sequelae of irradiation result in tissue devitalization (e.g., ischemia, fibrosis, and atrophy) where wound healing capacity is impaired. Fat-derived products may work to treat such pathology.

METHODS

Nonlethal irradiation at various doses (5, 10, and 15 Gy) and frequencies (one to three times on sequential days) was delivered to dorsal skin of nude mice, and subsequent gross and microscopic changes were evaluated for up to 4 weeks. Cutaneous punch wounds were then created to compare wound healing in irradiated and nonirradiated states. Wounds were also locally injected with vehicle, cultured adipose-derived stem cells, centrifuged fat tissue, or micronized cellular adipose matrix, and the therapeutic impact was monitored for up to 15 days.

RESULTS

Nude mice given total doses greater than 15 Gy spontaneously developed skin ulcers, and radiation damage was dose-dependent; however, a fractionated irradiation protocol was able to reduce the damage. Histologic assessment revealed dose-dependent dermal fibrosis/thickening and subcutaneous atrophy. Dose-dependent (5 to 15 Gy) impairment of wound healing was also evident. At the highest dosage (15 Gy three times), open wounds persisted on day 15. However, wounds injected with cultured adipose-derived stem cells were nearly healed on day 12, and those treated with injection of centrifuged fat or micronized tissue healed faster than untreated controls (p < 0.05). There was no significant differences between treated groups.

CONCLUSIONS

Tissue devitalization by irradiation was dose-dependent, although fractionated protocols helped to reduce it. Adipose-derived stem cells and other fat-derived products harboring adipose-derived stem cells successfully revitalized irradiated tissues and accelerated wound healing.

A New Technique in Management of Depressed Posttracheostomy Scars

BACKGROUND

The goals of tracheostomy scar revision are filling of the depressed area, providing easy sliding of skin over the trachea. There are various techniques described to correct this situation. In this article, a modification of split sternocleidomastoid (SCM) muscle flap used in the correction of posttracheostomy defects is described.

METHODS

Thirteen patients who had depressed scars after tracheostomy are included in this study. The mean patient age was 44 years (range, 27-56 years). All patients who suffered from tracheal tug, dysphagia, and bad appearance are included in the study. The area with the depressed scar is de-epithelialized after incising around the depression. Bilateral SCM muscles are split in the coronal plane toward superior half of the muscle while leaving the posterior part of the muscle attached to the bone. After elevation, both SCM muscle flaps are overlapped in the midline.

RESULTS

The mean follow-up period of the patients was 11 months (range, 5-20 months). Tracheal tug and dysphagia complaints were resolved in all patients. The depressed area due to the scar was either reduced or completely recovered in all the patients. Apart from 1 hematoma case, none of the early or late complications such as infection, wound dehiscence, skin necrosis, seroma, recurrence, or neck contracture was seen.

CONCLUSIONS

We think that this technique, which gives functionally and aesthetically satisfying results, can be used safely in depressed scars formed after tracheostomy and treatment of functional impairment due to this procedure.

Fat Grafting for Burn, Traumatic, and Surgical Scars

Fat grafting provides a reliable modality with expanding usefulness in reconstructive plastic surgery. Owing to its mechanical and theorized regenerative properties, adipose tissue can improve scar qualities and scar related symptoms when grafted adjacent to or within a scar. In this article, the literature describing the effect of fat grafting on various types of scars, current scientific understanding of fat grafting for scars, and our current approach to the management of problematic burn scars are reviewed.

Evidences of autologous fat grafting for the treatment of keloids and hypertrophic scars

Introduction

Since the 1980s, the use of autologous fat grafting has been growing in plastic surgery. Recently, this procedure has come to be used as a treatment for keloids and hypertrophic scars mainly due to the lack of satisfactory results with other techniques. So far, however, it lacks more consistent scientific evidence to recommend its use. The aim of this study was to review the current state of autologous fat grafting for the treatment of keloids and hypertrophic scars, their benefits and scientific evidences in the literature.

Method

A review in the Pubmed database was performed using the keywords "fat grafting and scar", "fat grafting and keloid scar" and "fat grafting and hypertrophic scar." Inclusion criteria were articles written in English and published in the last 10 years, resulting in 15 studies.

Results

These articles indicate that autologous fat grafting carried out at sites with pathological scars leads to a reduction of the fibrosis and pain, an increased range of movement in areas of scar contraction, an increase in their flexibility, resulting in a better quality of scars.

Conclusion

So far, evidences suggest that autologous fat grafting for the treatment of keloids and hypertrophic scars is associated with a better quality of scars, leading to esthetic and functional benefits. However, this review has limitations and these findings should be treated with reservations, since they mostly came from studies with low levels of evidence.

Autologous fat grafting in keloids and hypertrophic scars: a review

Keloid and hypertrophic scars are unique human dermal fibroproliferative disorders of the injured skin and are associated with pain, itch and can cause functional limitations. A number of genetic, systemic and local factors have been identified in the formation of keloids and hypertrophic scars. Studies have shown that adipose-derived stem cells have angiogenic and antiapoptotic properties which has effects on wound healing, soft-tissue restoration and scar remodelling, and thus may have a role in managing keloid scaring. However, this role is not well described in the literature. A systemic review of available literature was thus undertaken, regarding the use of fat grafting in treatment of keloids and hypertrophic scarring. In total, 858 articles were identified, with ten studies ultimately fulfilling inclusion criteria. There were no studies specifically isolating the keloids and hypertrophic group of patients, and thus quantitative data were completely lacking from the literature. There were, however, individual cases described, and qualitatively encouraging clinical results were reported for the use of fat grafting on keloids and hypertrophic scars. Combined with the current theoretical and immunohistochemical understanding through other laboratory and animal studies, fat grafting may play a role in the treatment of keloids and hypertrophic scaring; however, specific evidence is currently lacking. The role for further research is clear.

Keloid and hypertrophic scars are difficult to treat conditions. Some studies have suggested that fat cells may have a role in managing these scars although this role is not well described in the literature. We perform a systematic review of available literature, examining the evidence for this.

The power of fat and its adipose-derived stromal cells: emerging concepts for fibrotic scar treatment

Lipofilling or lipografting is a novel and promising treatment method for reduction or prevention of dermal scars after injury. Ample anecdotal evidence from case reports supports the scar‐reducing properties of adipose tissue grafts. However, only a few properly controlled and designed clinical trials have been conducted thus far on this topic. Also, the underlying mechanism by which lipofilling improves scar aspect and reduces neuropathic scar pain remains largely undiscovered. Adipose‐derived stromal or stem cells (ADSC) are often described to be responsible for this therapeutic effect of lipofilling. We review the recent literature and discuss anticipated mechanisms that govern anti‐scarring capacity of adipose tissue and its ADSC. Both clinical and animal studies clearly demonstrated that lipofilling and ADSC influence processes associated with wound healing, including extracellular matrix remodelling, angiogenesis and modulation of inflammation in dermal scars. However, randomized clinical trials, providing sufficient level of evidence for lipofilling and/or ADSC as an anti‐scarring treatment, are lacking yet warranted in the near future. © 2017 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd

Autologous fat grafting for scars, healing and pain: a review

INTRODUCTION

Current guidelines suggest a multimodal approach to treating scars but there is no gold standard for treatment; however, there is exciting therapeutic potential for the use of autologous fat grafting (AFG). Functional and aesthetic improvements have been reported, including pain relief and scar quality improvement.

AIMS

To explore the current evidence regarding the use of AFG in hypertrophic and painful scars.

METHODS

A systematic review of the literature was conducted using 11 MeSH terms in PubMed, Medline and EMBASE. English studies that used AFG to treat scars in human participants were included.

RESULTS

A total of 746 studies were found and 23 studies (from 2008 to 2016) were included: five studies were evidence level V; nine studies were evidence level IV; eight were evidence level III; and one study was evidence level II. A total of 1158 patients were assessed for improvement in scar characteristics including colour, thickness, volume, pain and restoration of function at affected sites, following treatment. Positive outcomes were noted for all parameters and a significant improvement in AFG's analgesic effect was recorded in 567 out of 966 patients, P < 0.05.

DISCUSSION

AFG is a minimally invasive and safe approach to treating scars, a promising alternative to surgical excision. The technique of blunt cannula insertion optimises the release of scar retraction, which contributes to the analgesic effect of this treatment method. The evidence supports current theories of mesenchymal stem cell's regenerative and anti-inflammatory properties responsible for scar healing. There are limited high quality studies to support its use and future randomised controlled trials should be conducted.

The Effect of Lipoaspirates on Human Keratinocytes

BACKGROUND

One increasingly important trend in plastic, reconstructive, and aesthetic surgery is the use of fat grafts to improve cutaneous wound healing. In clinical practice, lipoaspirates (adipose tissue harvested by liposuction) are re-injected in a procedure called lipofilling. Previous studies, however, mainly evaluated the regenerative effect of isolated adipocytes, adipose-derived stem cells, and excised en bloc adipose tissue on keratinocytes, whereas no study to date has examined the effect of lipoaspirates.

OBJECTIVES

The authors aimed to investigate differences in the regenerative property of en bloc adipose tissue and lipoaspirates on keratinocytes.

METHODS

Human keratinocytes, lipoaspirates, and en bloc adipose tissue from 36 healthy donors were isolated. In vitro proliferation, differentiation, migration, stratification, and wound healing of keratinocyte monolayers were measured. Furthermore, secreted levels of VEGF, bFGF, IGF-1, MMP-9, and MIF were detected by ELISA.

RESULTS

Migration, proliferation, and wound healing of keratinocytes were increased by lipoaspirates. Interestingly, the effect of lipoaspirates on keratinocyte proliferation was significantly higher than by en bloc adipose tissue after 5 days. The differentiation of keratinocytes was equally attenuated by lipoaspirates and en bloc adipose tissue. Stratification of keratinocyte layers was enhanced by lipoaspirates and en bloc fat when compared to controls. Lipoaspirates secrete higher levels of bFGF, whereas higher levels of VEGF and IGF-1 are released by en bloc adipose tissue.

CONCLUSION

We show that lipoaspirates and en bloc adipose tissue have a regenerative effect on keratinocytes. One reason for the higher effect of lipoaspirates on keratinocyte proliferation may be the secretion of different cytokines.

The Use of Autologous Fat Grafting for Treatment of Scar Tissue and Scar-Related Conditions: A Systematic Review

BACKGROUND

Scar tissue can cause cosmetic impairments, functional limitations, pain, and itch. It may also cause emotional, social, and behavioral problems, especially when it is located in exposed areas. To date, no gold standard exists for the treatment of scar tissue. Autologous fat grafting has been introduced as a promising treatment option for scar tissue-related symptoms. However, the scientific evidence for its effectiveness remains unclear. This systematic review aims to evaluate the available evidence regarding the effectiveness of autologous fat grafting for the treatment of scar tissue and scar-related conditions.

METHODS

A systematic literature review was performed using MEDLINE, Cochrane Library, EMBASE, and Web of Science. No language restrictions were imposed.

RESULTS

Twenty-six clinical articles were included, reporting on 905 patients in total. Meta-analysis was not performed because of the heterogeneous methodology demonstrated among the articles. Main outcome measures were scar appearance and skin characteristics, restoration of volume and/or (three-dimensional) contour, itch, and pain. All publications report a beneficial effect of autologous fat grafting on scar tissue. There is statistical significant improvement of the scar appearance, skin characteristics, and pain. Itch and restoration of volume and three-dimensional contour also improved.

CONCLUSIONS

Autologous fat grafting is used to improve a variety of symptoms related to scar tissue. This systematic review suggests that autologous fat grafting provides beneficial effects with limited side effects. However, the level of evidence and methodological quality are quite low. Future randomized controlled trials with a methodologically strong design are necessary to confirm the effects of autologous fat grafting on scar tissue and scar-related conditions.

Micronized cellular adipose matrix as a therapeutic injectable for diabetic ulcer

Background: Despite the clinical potential of adipose-derived stem/stromal cells (ASCs), there are some clinical difficulties due to the regulation of cell therapies. Materials & methods: Micronized cellular adipose matrix (MCAM) injectable was prepared through selective extraction of connective tissue fractions in fat tissue only through mechanical minimal manipulation procedures. Results: It retained some capillaries and ASCs, but most adipocytes were removed. The presence of viable ASCs, vascular endothelial cells was confirmed and ASCs of MCAM kept intact mesenchymal differentiation capacity. In diabetic mice, skin wounds treated with MCAM showed significantly accelerated healing compared with phosphate-buffered saline-treated ones. Conclusion: The proven potential of MCAM to accelerate healing in ischemic diabetic ulcers may offer a simple, safe and minimally invasive means for tissue repair and revitalization.

Intralesional injection treatment of hypertrophic scars and keloids: a systematic review regarding outcomes

Background

The aim of this review was to explore the existing body of literature focusing on the intralesional treatments of keloids and hypertrophic scars.

Methods

A comprehensive systematic review of related articles was conducted across multiple databases. Article selection was limited to those published in the English language between 1950 and 2014. Search terms for the on-line research were “scar(s),” “keloid(s),” “hypertrophic,” “injection,” “intralesional,” and “treatment”.

Results

The initial search returned 2548 published articles. After full text review, the final search yielded 11 articles that met inclusion criteria. A total of 14 patient samples in 11 articles were collected. The most frequent intralesional injection treatment studied was triamcinolone (n = 5), followed by bleomycin (n = 3), 5-fluorouracil (n = 2), verapamil (n = 2), cryosurgery, and collagenase. The scar height reduction for all but one study was demonstrated, with acceptable complication and recurrence rate. Only three articles reported a follow-up period longer than 18 months, and only two studies used standardized outcome criteria with a quantitative scale.

Conclusions

Although many treatment options have already been described in the literature, there is no universally accepted treatment resulting in permanent hypertrophic or keloid scar ablation. The lack of adequately long-term powered randomized controlled trials does not permit to establish definitive conclusions with implications for routine clinical practice.

Level of evidence

III/Therapeutic

Future Perspectives of Fat Grafting

Autologous fat grafting is an exciting part of plastic and reconstructive surgery. Fat serves as a filler and its role in tissue regeneration will likely play a more important role in our specialty. As we learn more about the basic science of fat grafting and the standardized techniques and instruments used for fat grafting, this procedure alone or in conjunction with invasive procedures may be able to replace many operations that we perform currently. Its minimally invasive nature will benefit greatly our cosmetic and reconstructive patients, and may even achieve better clinical outcomes.

The versatility of autologous fat transplantation in correction of facial deformities: a single-center experience

Deformities in the craniofacial region are of great social and functional importance. Several surgical techniques have been used to treat such pathologies often with high morbidity and lacking the ability to address smaller contour defects. The minimally invasive technique of fat transplantation has evolved rapidly within the last few decades. The objective of this paper is to present the versatility and applicability of fat transplantation in a wide range of contour deformities in the craniofacial region. We share our experiences in treating 13 patients with autoimmune disorders, congenital malformations, and acquired defects. Future perspectives of fat transplantation in the field of craniofacial reconstruction are discussed.

Adipose tissue-derived stromal cells inhibit TGF-β1-induced differentiation of human dermal fibroblasts and keloid scar-derived fibroblasts in a paracrine fashion

BACKGROUND

Adipose tissue-derived stromal cells augment wound healing and skin regeneration. It is unknown whether and how they can also influence dermal scarring. The authors hypothesized that adipose tissue-derived stromal cells inhibit adverse differentiation of dermal fibroblasts induced by the pivotal factor in scarring, namely, transforming growth factor (TGF)-β.

METHODS

TGF-β1-treated adult human dermal fibroblasts and keloid scar-derived fibroblasts were incubated with adipose tissue-derived stromal cell-conditioned medium and assessed for proliferation and differentiation, particularly the production of collagen, expression of SM22α, and development of hypertrophy and contractility.

RESULTS

TGF-β1-induced proliferation of adult human dermal fibroblasts was abolished by adipose tissue-derived stromal cell-conditioned medium. Simultaneously, the medium reduced SM22α gene and protein expression of TGF-β1-treated adult human dermal fibroblasts, and their contractility was reduced also. Furthermore, the medium strongly reduced transcription of collagen I and III genes and their corresponding proteins. In contrast, it tipped the balance of matrix turnover to degradation through stimulating gene expression of matrix metalloproteinase (MMP)-1, MMP-2, and MMP-14, whereas MMP-2 activity was up-regulated also. Even in end-stage myofibroblasts (i.e., keloid scar-derived fibroblasts), adipose tissue-derived stromal cell-conditioned medium suppressed TGF-β1-induced myofibroblast contraction and collagen III gene expression.

CONCLUSION

The authors show that adipose tissue-derived stromal cells inhibit TGF-β1-induced adverse differentiation and function of adult human dermal fibroblasts and TGF-β1-induced contraction in keloid scar-derived fibroblasts, in a paracrine fashion.