Low osmolality and shear stress during liposuction impair cell viability in autologous fat grafting

Fat Grafting the Male Face

There are many developmental sexual dimorphisms of the human face, and thereby differences in aging based on sex. Sensitivity regarding the nature of the changes that are unique to the male face as well as understanding men's unique aesthetic goals will allow the skilled practitioner to tailor rejuvenating treatments accordingly. Fat grafting of the male face has not been extensively described but is an excellent tool for facial rejuvenation either as an adjunct or a stand-alone procedure. Each treatment area demands different techniques and special attention to avoid unintentional feminization.

Effects of epinephrine, lidocaine, and prilocaine on viability and differentiation capacity of human adipose stem cells

INTRODUCTION

Local anesthetics (LAs) are routinely administered in plastic and reconstructive surgery, e.g., as tumescent anesthesia adjunct in liposuction. Historically, these substances were assumed to act cytotoxically. Thus, the application of LA was avoided when handling adipose stem cells (ASCs). We recently determined that most LAs are not cytotoxic when ASCs are exposed to concentrations used for tumescent liposuction. However, there is limited information when combining LA with epinephrine and about the effects of prilocaine on ASCs.

METHODS

We analyzed the effects of prilocaine or lidocaine in co-exposure with epinephrine on the viability of primary human ASCs, i.e., proliferation, metabolic activity, and cytotoxicity, using crystal violet-staining, PrestoBlue®-, and WST-1 assay. We quantified the impact of short-term incubation of lidocaine and epinephrine on the differentiation of ASCs into the adipogenic, chondrogenic, and osteogenic lineage.

RESULTS

After 2 h, prilocaine (10 mM) significantly reduced metabolic activity and cell numbers, whereas lidocaine only inhibited metabolic activity. After 6 h, prilocaine (10 mM) and lidocaine significantly decreased metabolic activity as well as cell numbers. The application of high concentrations of epinephrine did not affect cell numbers but diminished metabolic activity. Combining lidocaine with epinephrine had no additional cytotoxic effect. Differentiation into the chondrogenic lineage was significantly inhibited by epinephrine.

CONCLUSIONS

Deducing from our data, neither lidocaine combined with epinephrine nor prilocaine has a cytotoxic impact on ASCs in vitro at concentrations equivalent to those in tumescent anesthesia and has no long-lasting effect on the differentiation capacity of ASCs into the osteogenic and adipogenic lineage.

Quality and Vitality of Autologous Fat Grafts Harvested by Different Techniques: A Clinical Comparison Study

BACKGROUND

Unpredictable outcomes with autologous fat grafting due to reabsorption processes present a major challenge for healthcare providers and patients. A higher number of viable adipocytes is considered to result in a higher volume being retained. Although various adverse factors have been extensively researched, other potential parameters have been less investigated or even neglected.

OBJECTIVE

The aim of this study was to investigate the harvesting process of adipose tissue as the primary cause of cell damage and to determine the risk factors associated with low cell survival.

METHODS

Thirty-nine male and female subjects undergoing planned elective liposuction or abdominoplasty were enrolled. Forty-seven lipoaspirates harvested by different liposuction techniques were analyzed. RNA isolation and real-time polymerase chain reaction was performed to elucidate differences in the expression of various adipocyte markers. Furthermore, scanning electron microscopy was performed on various samples to determine the cell damage caused by the different techniques.

RESULTS

A statistically significant lower expression of peroxisome proliferator-activated receptor γ was detected in subjects with a higher BMI. A trend towards a lower expression of perilipin 1 in lipoaspirates harvested by a super wet + ultrasound technique, compared with dry and super wet techniques, was shown. The lowest level of cell damage determined from scanning electron microscopy images was in lipoaspirates harvested by the super wet + ultrasound technique, and this level was statistically significantly different from those obtained by the 2 other techniques.

CONCLUSIONS

Optimization of the outcome in autologous fat grafting may be feasible by targeting and optimizing the harvesting process as a main risk factor for impaired adipocyte viability. Ultrasound-assisted liposuction might be considered a suitable harvesting technique.

LEVEL OF EVIDENCE: 5

Modern Fat Grafting Techniques to the Face and Neck

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand age-related changes to the face and neck and pertinent anatomy and discuss important aspects of fat graft harvesting, processing, and infiltration. 2. Recognize key differences between common techniques for fat processing and infiltration and develop a plan for patients based on site-specific facial anatomical zones. 3. Appreciate the utility of fat grafting as an adjunct to other facial rejuvenating procedures such as face lift and blepharoplasty procedures and list the potential complications from fat grafting to the face and neck.

SUMMARY

Fat grafting to the face and neck aids in volume restoration, thereby addressing soft-tissue atrophy associated with the aging face, acquired conditions, or congenital malformations. Often, fat grafting may sufficiently restore facial volume alone or in conjunction with other facial rejuvenation procedures. Facial/neck fat grafting requires a systematic and thoughtful approach, with special care to atraumatic technique. This CME article covers the principles and techniques for modern facial fat grafting to the face and neck. Increasing data support the ability of autologous fat to produce significant and sustainable appearance-related changes. The authors follow the general principles of the Coleman technique for facial fat grafting and have observed tremendous success over the years. Other techniques for facial fat grafting are also discussed including microfat and nanofat processing. As the understanding of facial fat compartments continues to evolve, the authors may better predict fat grafting outcomes following augmentation. Finally, the technique described as "lipotumescence" has been successfully used in the breast and other regions of the body that have radiation damage and is discussed in this article specifically for the face and neck.

European Survey Study Among Plastic/Breast Surgeons on the Use of and Opinion Toward Autologous Fat Transfer: With Emphasis on Breast Surgery

Objective. The aim of this study is to examine the experience of European surgeons on autologous fat transfer (AFT) and highlight differences between countries and levels of experience. Background Data. The popularity of AFT causes an increase in sophisticated scientific research and clinical implementation. While results from the former are well-documented, important aspects of the latter are far less recognized. Methods. An international survey study about surgeon background, besides AFT familiarity, technique, and opinion, was distributed among surgeons from 10 European countries. The differences between countries and levels of experience were analyzed using a logistic regression model. Results. The mean respondent age, out of the 358 completed questionnaires, was 46 years. Ninety-seven percent of the respondents were plastic surgeons, who practiced AFT mostly in breast surgery and considered themselves experienced with the technique. The thigh and abdomen were less favored harvest locations by the Belgium and French respondents, respectively, and both the French and Austrian respondents preferred manual aspiration over liposuction in harvesting the fat. Despite minor differences between countries and experience, the intraglandular space was injected in all subgroups. Conclusions. The expanding use of AFT in Europe will lead to more experience and heterogeneity regarding the technique. However, despite an obvious adherence to Coleman's method, deviations thereof become more apparent. An important example of such a deviation is the ongoing practice of intraglandular AFT despite being a contraindication in various European guidelines. These unsafe practices should be avoided until scientific clarification regarding oncological safety is obtained and should therefore be the focus of surgeon education in Europe.

Uncultivated stromal vascular fraction is equivalent to adipose-derived stem and stromal cells on porous polyurethrane scaffolds forming adipose tissue in vivo

OBJECTIVES/HYPOTHESIS

To find an alternative approach to contemporary techniques in tissue augmentation and reconstruction, tissue engineering strategies aim to involve adipose-derived stem and stromal cells (ASCs) harboring a strong differentiation potential into various tissue types such as bone, cartilage, and fat.

STUDY DESIGN

Animal research.

METHODS

The stromal vascular fraction (SVF) was used directly as a cell source to provide a potential alternative to contemporary ASC-based adipose tissue engineering. Seeded in TissuCol fibrin, we applied ASCs or SVF cells to porous, degradable polyurethane (PU) scaffolds.

RESULTS

We successfully demonstrated the in vivo generation of volume-stable, well-vascularized PU-based constructs containing host-derived mature fat pads. Seeded human stem cells served as modulators of host-cell migration rather than differentiating themselves. We further demonstrated that preliminary culture of SVF cells was not necessary.

CONCLUSIONS

Our results bring adipose tissue engineering, together with automated processing devices, closer to clinical applicability. The time-consuming and cost-intensive culture and induction of the ASCs is not necessary.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:E206-E213, 2018.

Autologous Fat Transfer for Facial Rejuvenation: A Systematic Review on Technique, Efficacy, and Satisfaction

Background

Parallel to the steady decline in surgical aesthetic procedures to the face, dermal fillers seem to have gained a more prominent place in facial rejuvenation over the last couple of years. As a dermal, facial filler, autologous fat transfer (AFT) seems to have real potential because of the biocompatibility of adipose tissue besides being a procedure with few and primarily minor complications. This systematic review aims to evaluate the available evidence regarding the safety and effectiveness of AFT for facial rejuvenation.

Method

A systematic review after the Preferred-Reporting-Items-for-Systematic-Reviews-and-Meta-Analysis (PRISMA) statement was conducted. MEDLINE, Embase, and Cochrane Library were searched up to December 2016, with no language restrictions imposed. Case series, cohort studies, and randomized controlled trials (RCTs) reporting on relevant outcomes were included.

Results

Eighteen clinical articles were included, reporting on 3,073 patients in total over a mean follow-up period of 13.9 months. Meta-analysis showed an overall complication rate of 6% (95% CI 3.0-14.0), with hematoma/ecchymosis (5%), fat necrosis/oil cysts (2%), and irregular fat distribution and scars (both 2%) being among the most reported. No major complications were reported, and the overall patient satisfaction rate was 81%.

Conclusion

Although the evidence in this systematic review is still limited and plagued by heterogeneity between studies, AFT seems to be a promising method in facial rejuvenation with fewer complications than other fillers and high patient satisfaction rates. Further large-cohort, preferably multicenter, RCTs should substantiate these results through quantifiable volumetric assessment tools and validated patient questionnaires, while adhering to predetermined nomenclature in terms of complications.