Fat injection in severe burn outcomes: a new perspective of scar remodeling and reduction

Autologous Fat Grafting Restores Soft-tissue Contour Deformities after Vascular Anomaly Surgery

Soft-tissue loss is expected after resection of large vascular lesions. Autologous fat transfer improves asymmetries; however, systematic outcomes are not previously described for vascular anomaly reconstruction.

Combined Non-Ablative Laser and Microfat Grafting for Burn Scar Treatment

BACKGROUND

Burn scar treatment persists as an unsolved problem, involving thousands of affected patients disfigured for life.

OBJECTIVES

We sought to present our experience with the use of combined treatments for patients with burn scars.

METHODS

This was a case series report of the senior author's experience during 8 years utilizing the combined treatments of Fraxel Restore (fractional laser) and microfat graft injection for 288 patients with burn scars.

RESULTS

Laser treatment reduced scar intensity and attenuated skin irregularities and hyperpigmentation. All patients demonstrated marked improvement of skin texture and an increase in scar softness after 3 sessions of microfat grafting. However, the degree of improvement varied between patients and was related to the severity of the scar and the type of tissue. Overall, a 40% to 80% improvement was noted in our patients. All patients and their families expressed satisfaction with the results.

CONCLUSIONS

The combined treatment of Fraxel and microfat grafting is an effective technique for improving the appearance of a hypertrophic scar or keloid on burn patients. Fat tissue stem cells may have helped to repair the damaged skin.

LEVEL OF EVIDENCE: 4

The Effects of Adipose-Derived Stem Cell-Differentiated Adipocytes on Skin Burn Wound Healing in Rats

Both adipose-derived stem cells (ADSCs) and fat grafting promote burn wound healing, but whether adipogen-derived cells using various inducers such as 3-isobutyl-1-methylxanthine (IBMX) and insulin affect wound healing is unknown. Herein, ADSC-differentiated adipogenic lineages were used in rat burn wounds to evaluate wound healing potential. ADSCs were cultivated using six different adipogenic differentiation conditions (IBMX ± insulin, IBMX for 5 days, high and low Dulbecco's modified Eagle's medium) and in vitro morphological changes and cell proliferations during adipogenic differentiation were recorded. Intermediate burn wounds were inflicted in 15 Wistar male rats. Afterwards, the rats were divided into five groups for subcutaneous injections under the wounds: control; ADSCs; differentiated adipocytes (-IBMX+INSULIN and +IBMX[D1-5]+INSULIN) and fat prepared by Coleman technique. Macroscopic changes and histology were documented for 3 weeks. Repeated measures analysis of variance was performed to analyze cell growth and wound healing with a statistical level set of P < .05. Induction cocktails significantly reduced proliferation and induced lipid droplet accumulation. Conditioning without insulin induced the least lipid accumulation, while discontinuing IBMX generated larger adipocytes (P < .001). Adipogenic differentiated ADSCs had similar wound healing abilities with ADSC and fat injections, but differentiated adipocytes (+IBMX[D1-5]+INSULIN) and fat grafting accelerated the early healing process relative to ADSC (P < .001). Reduced fibrosis and mild inflammatory infiltration limited to superficial dermis were observed in +IBMX(D1-5)+INSULIN and fat injection groups, while those reactions were mild to moderate in ADSC group. Differentiated adipocytes achieve similar wound healing results compared with ADSC and fat injections, but differentiated adipocytes (+IBMX[D1-5]+INSULIN) and fat grafting accelerate early healing relative to ADSC.

Heterogeneity of mast cells and expression of Annexin A1 protein in a second degree burn model with silver sulfadiazine treatment

Mast cells (MCs) participate in all stages of skin healing and one of their mediators is the Annexin A1 protein (AnxA1), linked to inflammation, proliferation, migration and apoptosis processes, but not studied in thermal burns yet. Therefore, our objectives were to evaluate the behavior of MCs and AnxA1 in a second degree burn model, treated or not with silver sulfadiazine 1% (SDP 1%) and associated to macrophages quantification and cytokines dosages. MCs counts showed few cells in the early stages of repair but increased MCs in the final phases in the untreated group. The normal skin presented numerous tryptase-positive MCs that were reduced after burning in all analyzed periods. Differently, few chymase-positive MCs were observed in the early stages of healing, however, increased chymase-positive MCs were found at the final phase in the untreated group. MCs also showed high immunoreactivity for AnxA1 on day 3 in both groups. In the tissue there was a strong protein expression in the early stages of healing, but in the final phases only in the SDP treated animals. TNF-α, IL-1β, IL-6, IL-10 and MCP-1 levels and macrophages quantification were increased in inflammation and reepithelialization phases. Reduced IL-1β, IL-6 and IL-10 levels and numerous macrophages occurred in the treated animals during tissue repair. Our results indicate modulation in the profile of MCs and AnxA1expression during healing by the treatment with SDP 1%, pointing them as targets for therapeutic interventions on skin burns.

Recipient wound bed characteristics affect scarring and skin graft contraction

The use of autograft skin is essential in the treatment of full thickness burns and large cutaneous defects. Both autograft thickness and condition of the wound bed modulate aesthetic and functional outcomes. Thicker autografts contract less and maintain greater functionality as the scar matures. The presence of hypodermis can also positively affect the eventual appearance and functionality of the wound site by modulating contraction and alleviating inflammation and cellular stress responses. In this study, we characterize wound-site physical and cellular characteristics following split-thickness skin grafting onto hypodermis vs. onto fascia. Compared to autografts grafted onto fascia, identical thickness autografts grafted onto fat demonstrated reduced contraction, enhanced mobility and vascularity, and reduced topographical variability. Grafts onto fat also showed reduced levels of myofibroblasts and leukocytic infiltration. The status of the wound bed prior to engraftment is an important contributor of skin quality outcome. The presence of hypodermis is associated with improved functional and aesthetic qualities of split thickness skin grafts, which are correlated with reduced presence of myofibroblasts and leukocytic infiltration.

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