The Current State of Fat Grafting: A Review of Harvesting, Processing, and Injection Techniques

Comparing the safety profiles of implants and autologous fat grafting in gluteal augmentation: A systematic review

Gluteal augmentation has become a popular esthetic procedure since its inception. The main methods are augmentation using implants or autologous fat grafting, which is the harvesting and grafting of patients' own fat tissue. The last review comparing the safety of these methods was written 7 years ago, which warrants the writing of a new one. PubMed, Cochrane, and Medline were searched for studies focusing on the methods of gluteal augmentation listed previously. Five search terms were used and 15 studies fulfilled the criteria. The data were cataloged according to the method described and outcomes compared. Seven articles focused on gluteal implants and another seven assessed autologous fat grafting, whereas one detailed both. The most common complications in 524 implant procedures were wound dehiscence (9.16%), excessive implant palpability (5.92%), and seroma (3.82%), with an overall complication rate of 25%. The most common complications in 1788 gluteal fat augmentation procedures were seroma (6.9%), infection (3.0%), and transient sciatic paresthesia (1.0%), with an overall complication rate of 13%. Several articles listed satisfaction figures, but these were not assessed because this article was not powered to assess this outcome. Overall, gluteal augmentation using autologous fat grafting leads to fewer postoperative complications than implants and allows greater contouring of the buttocks and the surrounding areas. However, it can also be a far more dangerous procedure if certain recommendations are not followed.

Current Fat Grafting Practices and Preferences: A Survey from Members of ISPRES

Fat grafting has established its niche in a wide spectrum of aesthetic and reconstructive procedures. A consensus-based method of harvest, processing, enrichment, injection, and assessment is lacking, despite the rising trends in its application. We conducted a survey among plastic surgeons to evaluate and identify trends of fat grafting practices.

An Innovative Surgical Technique to Obtain an Adipose-Derived Stromal Cell-Rich Graft for the Treatment of Osteoarthritis: Technical Note

Osteoarthritis (OA) is one of the main causes of disability worldwide and is caused by the progressive degeneration of joint tissues, ultimately leading to chronic pain and loss of function. Intraarticular delivery of mesenchymal stromal cells, such as adipose-derived stromal cells (ASCs), is being actively investigated due to their trophic properties observed in both preclinical and clinical studies. However, cell expansion and handling involve costly and time-consuming processes that limit their application. Recently, several devices and kits have been developed to isolate and process the stromal vascular fraction (SVF), a high biologically active compound of the adipose tissue, right at the patient’s bedside. In this study, we introduce a novel technique to obtain an SVF graft with a high content of ASCs for intraarticular injection directly from liposuction and with minimal equipment. In this technical note, we describe in detail the steps of the surgical technique as well as strategies to avoid common pitfalls and complications.

Fat Graft Retention: Adipose Tissue, Adipose-Derived Stem Cells, and Aging

SUMMARY

Over the past 30 years, there has been a dramatic increase in the use of autologous fat grafting for soft-tissue augmentation and to improve facial skin quality. Several studies have highlighted the impact of aging on adipose tissue, leading to a decrease of adipose tissue volume and preadipocyte proliferation and increase of fibrosis. Recently, there has been a rising interest in adipose tissue components, including adipose-derived stem/stromal cells (ASCs) because of their regenerative potential, including inflammation, fibrosis, and vascularization modulation. Because of their differentiation potential and paracrine function, ASCs have been largely used for fat grafting procedures, as they are described to be a key component in fat graft survival. However, many parameters as surgical procedures or adipose tissue biology could change clinical outcomes. Variation on fat grafting methods have led to numerous inconsistent clinical outcomes. Donor-to-donor variation could also be imputed to ASCs, tissue inflammatory state, or tissue origin. In this review, the authors aim to analyze (1) the parameters involved in graft survival, and (2) the effect of aging on adipose tissue components, especially ASCs, that could lead to a decrease of skin regeneration and fat graft retention.

CLINICAL RELEVANCE STATEMENT

This review aims to enlighten surgeons about known parameters that could play a role in fat graft survival. ASCs and their potential mechanism of action in regenerative medicine are more specifically described.

Recent advances in surgical techniques for breast reconstruction

Although the number of patients with breast cancer continues to rise worldwide, survival rates for these patients have significantly improved. As a result, breast cancer survivors are living longer, and quality of life after treatment is of increasing importance. Breast reconstruction is an important component that affects quality of life after breast cancer surgery. With the development of silicone gel implants in the 1960s, autologous tissue transfer in the 1970s, and tissue expanders in the 1980s, breast reconstruction has advanced over the decades. Furthermore, the advent of perforator flaps and introduction of fat grafting have rendered breast reconstruction a less invasive and more versatile procedure. This review provides an overview of recent advances in breast reconstruction techniques.

Evaluation of the Effect of Metoprolol Dosage on Fat Graft Survival

AIM

The aim of this study was to evaluate the effect of different metoprolol doses on fat graft survival.

MATERIAL AND METHOD

A total of 10 Sprague-Dawley rats were used in the study. The dorsal regions of the rats were separated into four quadrants: right and left cranial, and right and left caudal. Each quadrant was determined as a separate group. Fat grafts were harvested from the groin areas and incubated in 5 ml solutions containing 0.9% sodium chloride (control group), 1 mg/mL metoprolol (Group 1), 2 mg/mL metoprolol (Group 2), and 3 mg/mL metoprolol (Group 3), respectively. The fat grafts were then placed in pockets dissected in each of the 4 dorsal quadrants. After 3 months all the rats were euthanized. The fat grafts were removed together with the surrounding area to which they had passed. Histopathological examination was made with hematoxylin and eosin (HE) and Masson Trichrome staining, and immunohistochemical examination with fibroblast growth factor-2 and perilipin staining.

RESULTS

In the examinations made with HE and Masson Trichrome staining, the scores of Group 2 and Group 3 were determined to be significantly higher than those of the control group (p < 0.05). The Group 3 scores were significantly higher than those of Group 1 (p < 0.05). In the examinations made with fibroblast growth factor-2 staining, the scores of Group 2 and Group 3 were determined to be significantly higher than those of the control group (p < 0.05). The Group 3 scores were significantly higher than those of Group 1 and Group 2 (p < 0.05). In the examinations made with perilipin staining, the scores in Groups 1, 2, and 3 were higher than those of the control group (p < 0.05).

CONCLUSION

Although metoprolol has previously been shown to prolong the survival of fat grafts, the results of this study demonstrated immunohistochemically that as the metoprolol dose increased, so the quality and vitality of fat graft also increased.

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 .

Three-dimensional Quantitative Standards for Assessing Outcomes of Facial Lipotransfer: A Review

BACKGROUND

Reliable quantitative data are required to address the unpredictability of facial autologous fat grafting (AFG). Facial evaluation by 3D scanning technology is getting popular. However, this process lacks unified standards and the reliability assessments. This study aimed to summarize a set of standards to improve the 3D quantified reliability of AFG outcomes.

METHODS

A systematic review was used to collect the differences in and limitations of 3D assessments and analyze the effect of the quantification process on the AFG outcomes. Healthy subjects undergoing only one facial structural AFG and 3D assessments were included. The revealed specific issues guided the subsequent narrative review that involves 3D measurement and fat volume retention rate (FVRR) analysis. Criteria were formulated based on the narrative review.

RESULTS

The systematic review revealed the quantitative process to be operator-dependent. The intra-group FVRR in the postoperative 11+ month group varied significantly (P=.03). The review identified a set of 3D measurement standards, including two optimal software products, two necessary steps for preprocessing, and four testing criteria. We proposed a new calculation formula and parameter and recommended a segmental area analysis for assessing the outcomes of full-face fat grafting.

CONCLUSIONS

As far as the 3D evaluation of AFG outcomes is concerned, this is the first study to comprehensively analyze the process and set quantitative criteria. These standards would not only guide future research more reliably, but also provide fresh insight into the review of the past research. 3D measurement standards also apply to all face-related studies requiring 3D registration.

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 .

Condensing of Low-Density Fat by Mechanical Process Improves Fat Retention and Reduces Oil Cyst Formation in Breast Reconstruction

BACKGROUND

Although autologous fat grafting is a useful adjunct for breast reconstruction, its indications remain limited as large-volume fat grafting results in high absorption and complication rates. Low-density fat includes small numbers of viable cells and considerable oil, resulting in nodules and oil cysts. This study evaluated the volumization effect and complications with combined fat grafting of condense low-density fat and high-density fat.

METHODS

This retrospective, single-center study included 25 patients who underwent combined grafting of condensed low-density fat and high-density fat (CLDF + HDF) and 20 patients who underwent conventional Coleman fat grafting for breast reconstruction from December 2017 to January 2022. Retention rates and complications were evaluated by magnetic resonance imaging and ultrasound rates. Patient satisfaction was evaluated using a typical Likert scale. Photographs were taken and imageological examinations were performed before and after treatment.

OUTCOMES

Graft retention rate was higher in patients who underwent CLDF + HDF than Coleman fat grafting for breast reconstruction (38.40 ± 4.41% vs. 31.43 ± 5.43%, p <0.05). One patient in the CLDF + HDF grafting group, compared with twelve in the Coleman fat grafting group, developed oil cysts exceeding 1 cm. Patient satisfaction rate was higher in the CLDF + HDF grafting group.

CONCLUSIONS

Mechanical processes can concentrate the cellular content of LDF and remove oil, condensing LDF to the level of HDF. Combined grafting of CLDF optimized by mechanical processing and HDF is effective for breast reconstruction, with a higher retention rate and a lower incidence of complications than conventional Coleman fat grafting.

LEVEL OF EVIDENCE IV

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 .

“Achieving Optimal Clinical Outcomes in Autologous Fat Grafting: A Systematic Review of Processing Techniques”

BACKGROUND

Autologous fat grafting (AFG) is a versatile technique in reconstructive and cosmetic surgery. Graft processing is a key source of variability resulting in unreliable clinical outcomes, with no consensus on the optimal methodology. This systematic review identifies the evidence base supporting different processing paradigms.

METHODS

A systematic literature search was conducted using the PubMed, Scopus and The Cochrane Foundation databases. Studies comparing AFG processing methods and reporting long-term patient outcomes were identified.

RESULTS

Twenty-four studies (2413 patients) were identified. Processing techniques evaluated included centrifugation, decantation, washing, filtration, gauze rolling, as well as commercial devices and adipose-derived stem/stromal cell (ASC) enrichment methods. Objective volumetric and subjective patient-reported outcomes were discussed. There was a variable reporting of complications and volume retention rates. Complications were infrequent; palpable cysts (0-20%), surgical-site infections (0-8%) and fat necrosis (0-58.4%) were the most reported. No significant differences in long-term volume retention between techniques were found in AFG in the breast. In head and neck patients, greater volume retention was documented in ASC enrichment (64.8-95%) and commercial devices (41.2%) compared to centrifugation (31.8-76%).

CONCLUSIONS

Graft processing through washing and filtration, including when incorporated into commercial devices, results in superior long-term outcomes compared to centrifugation and decantation methods. ASC enrichment methods and commercial devices seem to have superior long-term volume retention in facial fat grafting.

Analysis of Fat Graft Survival and Platelet-Rich Plasma Effects: The Transcriptomic Differences

INTRODUCTION

Fat graft survival has been studied numerously but has not gone beyond hypothetical solutions. The molecular changes in survival of standard fat grafts and enhanced survival by platelet-rich plasma (PRP) are compared in this study to reveal the etiology that causes the loss of fat grafts after transplantation.

MATERIALS AND METHODS

A New Zealand rabbit's inguinal fat pads were excised and divided into three groups: Sham, Control (C), and PRP. Each weighing 1 g, C and PRP fat were placed into the bilateral parascapular area of the rabbit. After 30 days, the remaining fat grafts were harvested and weighed (C = 0.7 g, PRP = 0.9 g). All three specimens were put into transcriptome analysis. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes Analysis were done to compare the genetic pathways between the specimens.

RESULTS

Transcriptome analysis showed similar differential expressions in Sham vs. PRP and Sham vs. C comparisons, indicating the dominance of the cellular immune response in both C and PRP specimens. C and PRP comparison resulted in inhibited migration and inflammation pathways in PRP.

CONCLUSION

Fat graft survival is more related to immune responses than any other physiological process. PRP enhances survival by attenuating cellular immune reactions.

Autologous Fat Grafting in Reconstructive Breast Surgery: Clinically Relevant Factors Affecting the Graft Take

BACKGROUND

Autologous fat grafting is an effective tool for soft tissue augmentation in reconstructive breast surgery. Despite the major advantages of this minimally invasive approach, the unpredictability of graft survival presents challenges.

OBJECTIVES

No clear consensus on the optimal technique has yet been published and well-defined prospective studies investigating impairing factors are lacking. This aim of this study was to generate valuable fundamental data.

METHODS

Ten female patients undergoing elective autologous fat grafting after nipple-sparing mastectomy were enrolled. Punch biopsies and lipoaspirates were collected from the harvest site for histologic, gene expression, and scanning electron microscopic analysis. Noninvasive Lipometer measurements determining the subcutaneous adipose tissue thickness at the graft site were used to calculate the respective take rate. Patient- and surgery-related data were acquired and correlated with the take rate.

RESULTS

A statistically relevant correlation between the take rate and the existing mean subcutaneous adipose tissue thickness at the grafted breast prior to surgery was observed. An approximate correlation was identified regarding the number of previous grafting sessions, body weight, and BMI. No statistically significant correlation was demonstrated for age, harvest site, or the mean adipocyte size. A lower level of cell damage was observed in scanning electron microscopic samples of washed lipoaspirates; and a strong indirect correlation with the expression of the adipocyte markers FABP4 and PLIN1 was apparent.

CONCLUSIONS

Factors correlating to the take rate were identified. Future studies investigating the clinical relevance of each impairing factor are essential to contribute to the optimization of this valuable method.

LEVEL OF EVIDENCE: 4

Long-term in vivo survival of 3D-bioprinted human lipoaspirate-derived adipose tissue: proteomic signature and cellular content

Three-dimensional (3D)-bioprinted lipoaspirate-derived adipose tissue (LAT) is a potential alternative to lipo-injection for correcting soft-tissue defects. This study investigated the long-term in vivo survival of 3D-bioprinted LAT and its proteomic signature and cellular composition. We performed proteomic and multicolour flow cytometric analyses on the lipoaspirate and 3D-bioprinted LAT constructs were transplanted into nude mice, followed by explantation after up to 150 days. LAT contained adipose-tissue-derived stem cells (ASCs), pericytes, endothelial progenitor cells (EPCs) and endothelial cells. Proteomic analysis identified 6,067 proteins, including pericyte markers, adipokines, ASC secretome proteins, proangiogenic proteins and proteins involved in adipocyte differentiation and developmental morphogenic signalling, as well as proteins not previously described in human subcutaneous fat. 3D-bioprinted LAT survived for 150 days in vivo with preservation of the construct shape and size. Furthermore, we identified human blood vessels after 30 and 150 days in vivo, indicating angiogenesis from capillaries. These results showed that LAT has a favourable proteomic signature, contains ASCs, EPCs and blood vessels that survive 3D bioprinting and can potentially facilitate angiogenesis and successful autologous fat grafting in soft-tissue reconstruction.

Use of platelet-rich fibrin in fat grafts during facial lipostructure

BACKGROUND

This review was designed to discuss the safety and efficacy of using platelet-rich fibrin (PRF) in fat grafts during facial lipostructure.

METHODS

From January 2018 to December 2021, 650 fat grafts for facial lipostructure were performed in the authors' department. According to their wishes, we divided the patients into two groups: 498 patients were treated with autologous fat injection (control group), and 152 patients were treated with autologous fat injection combined with PRF. All of the patients were monitored for at least six months. The effects were evaluated via physician assessment and patient satisfaction rates, and the incidences of complications were compared.

RESULTS

All the cases had a degree of improvement after treatment. The patient satisfaction rate was 55.3% in the PRF group and 43.4% in the control group. In all, 68.4% of the patients in the PRF group and 58.2% in the control group indicated that one-stage surgery was sufficient to achieve the desired effect. According to the evaluation conducted by the plastic surgeon, 59.2% of patients in the PRF group and 47.0% in the control group achieved a perfect effect. A total of 76.3% of patients in the PRF group and 63.9% in the control group reported that one surgery achieved satisfactory results. The difference between the PRF and control groups was statistically significant.

CONCLUSION

Using an autologous fat graft during facial lipostructure is beneficial and safe when combined with PRF. The combination may enhance the effect and satisfaction rate. Further research and prospective clinical studies are needed to understand the role of PRF in fat grafting.

Macrophage-mediated extracellular matrix remodeling after fat grafting in nude mice

Clinical unpredictability and variability following fat grafting remain non-negligible problems due to the unknown mechanism of grafted fat retention. The role of the extracellular matrix (ECM), which renders cells with structural and biochemical support, has been ignored. This study aimed to clarify the ECM remodeling process, related cellular events, and the spatiotemporal relationship between ECM remodeling and adipocyte survival and adipogenesis after fat grafting. Labeled Coleman fat by the matrix-tracing technique was grafted in nude mice. The ECM remodeling process and cellular events were assessed in vivo. The related cytokines were evaluated by qRT-PCR. An in vitro cell migration assay was performed to verify the chemotactic effect of M2-like macrophages on fibroblasts. The results demonstrated that in the periphery, most of the adipocytes of the graft survived or regenerated, and the graft-derived ECM was gradually replaced by the newly-formed ECM. In the central parts, most adipocytes in the grafts died shortly after, and a small part of the graft-derived and newly-formed ECM was expressed with irregular morphology. Adipose ECM remodeling is associated with increased infiltration of macrophages and fibroblasts, as well as up-regulated expression of cytokines in the adipose tissue. To sum up, our results describe the various preservation mode of fat grafts after transplantation and underscore the importance of macrophage-mediated ECM remodeling in graft preservation after fat grafting. The appreciation and manipulation of underlying mechanisms that are operant in this setting stand to explore new therapeutic approaches and improve clinical outcomes of fat grafting.

Erector Spinae Plane Block is Equivalent to Tumescent Local Anesthesia for Perioperative Pain Control with Abdominal Harvest for Fat Grafting

There is increasing evidence that lidocaine is toxic to adipocytes and their precursors, which can contribute to the variability in fat graft resorption. Erector spinae plane (ESP) block is a new technique to provide analgesia of the trunk and would avoid lidocaine at the fat graft donor site. The aim of this study was to compare the efficacy of ESP block versus tumescent local anesthesia (TLA).

Methods

A retrospective review was performed for all patients who underwent autologous fat grafting from the abdomen at the University of New Mexico Hospital between February 2016 and March 2019. These patients received either ESP block or TLA during abdominal fat harvest. The primary endpoints were intraoperative, postoperative, and total morphine equivalents.

Results

There was no difference in the mean intraoperative, postoperative, and total morphine equivalents administered between the ESP and TLA groups.

Conclusions

ESP block is equivalent to TLA for analgesia when using an abdominal donor site for fat harvest. ESP block should be considered in fat-grafting cases to avoid the potential toxicity of lidocaine to the viability of adipocytes and preadipocytes.

Retropectoral Fat Graft Survival in Mammoplasty: Evaluation by Magnetic Resonance Imaging

BACKGROUND

Fat grafting is used in combination with mammoplasty to improve filling of the upper pole of the breasts. Its effectiveness remains in question due to unpredictable results. Difficulty in isolating the grafted fat and differentiating it from host tissues may hinder assessment of graft integration. The plane between the pectoral muscles is free of fat and has already been described with respect to placement of breast implants and fat grafting in breast surgeries. This study sought to evaluate via magnetic resonance imaging (MRI) the integration and retention of retropectoral fat grafts in mammoplasty.

METHODS

Thirty patients with breast flaccidity who desired to undergo mammoplasty were selected. Fat collected from the abdomen was separated by sedimentation and transferred to the retropectoral region after undermining of the breast and resection of excess tissue. The patients underwent MRI preoperatively and at three and six months after surgery. Fat volumes were calculated by multiplying the values for the major vertical, horizontal, and anteroposterior axes by the constant 0.523.

RESULTS

Twenty-five patients completed the study. The mean volume grafted was 116.4 ± 22.5 ml per breast. Six months after surgery, the mean fat graft volume in the retropectoral plane was 48.1 ± 25.71 ml, and the integration rate was 40.82% (range, 32.2-49.4%). The rate of complications related to fat grafting was 8%.

CONCLUSIONS

In mammoplasty, retropectoral fat grafting showed good integration rates and is a safe and predictable approach that can contribute to improving the outcomes of aesthetic and reconstructive breast surgeries.

LEVEL OF EVIDENCE IV, COHORT ANALYTIC STUDY

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 .

Office-Based Structural Autologous Fat Injection Laryngoplasty for Unilateral Vocal Fold Paralysis

Unilateral vocal fold paralysis (UVFP) is a common cause of incomplete glottic closure, leading to significant somatic and social disabilities. Office-based autologous fat injection laryngoplasty (AFIL) has been proposed as an effective treatment for glottic insufficiency but has not been well-studied for UVFP. We enrolled 23 patients who underwent office-based structural AFIL due to unilateral vocal paralysis at our institution between February 2021 and January 2022. In the procedure, autologous fat was harvested and injected into the vocal fold under the guidance of flexible digital endoscopy for structural fat grafting. The voice handicap index-10 (VHI-10) score and perceptual voice measurements were collected before the operation, 2 weeks postoperatively, and 3 months postoperatively. Twenty-two patients were followed-up for at least 3 months. The VHI-10 score improved significantly from 29.65 ± 8.52 preoperatively to 11.74 ± 7.42 at 2 weeks (p < 0.0001) and 5.36 ± 6.67 at 3 months (p < 0.0001). Significant improvements in grades of dysphonia (p < 0.0001), breathiness (p < 0.0001), and asthenia (p = 0.004) were also noted at 3 months postoperatively when perceptual measurements were investigated. Office-based structural AFIL is an effective treatment for improving voice-related disability for UVFP patients.

The Effects of Shear Force-Based Processing of Lipoaspirates on White Adipose Tissue and the Differentiation Potential of Adipose Derived Stem Cells

Autologous lipotransfer is a promising method for tissue regeneration, because white adipose tissue contains a heterogeneous cell population, including mesenchymal stem cells, endothelial cells, immune cells, and adipocytes. In order to improve the outcome, adipose tissue can be processed before application. In this study, we investigated changes caused by mechanical processing. Lipoaspirates were processed using sedimentation, first-time centrifugation, shear-force homogenization, and second-time centrifugation. The average adipocyte size, stromal vascular cell count, and adipocyte depot size were examined histologically at every processing step. In addition, the adipose derived stem cells (ADSCs) were isolated and differentiated osteogenically and adipogenically. While homogenization causes a disruption of adipocyte depots, the shape of the remaining adipocytes is not changed. On average, these adipocytes are smaller than the depot adipocytes, they are surrounded by the ECM, and therefore mechanically more stable. The volume loss of adipocyte depots leads to a significant enrichment of stromal vascular cells such as ADSCs. However, the mechanical processing does not change the potential of the ADSCs to differentiate adipogenically or osteogenically. It thus appears that mechanically processed lipoaspirates are promising for the reparation of even mechanically stressed tissue as that found in nasolabial folds. The changes resulting from the processing correspond more to a filtration of mechanically less stable components than to a manipulation of the tissue.

Specific features of ex-obese patients significantly influence the functional cell properties of adipose-derived stromal cells

Adipose-derived stromal cells (ADSC) are increasingly used in clinical applications due to their regenerative capabilities. However, ADSC therapies show variable results. This study analysed the effects of specific factors of ex-obese patients on ADSC functions. ADSC were harvested from abdominal tissues (N = 20) after massive weight loss. Patients were grouped according to age, sex, current and maximum body mass index (BMI), BMI difference, weight loss method, smoking and infection at the surgical site. ADSC surface markers, viability, migration, transmigration, sprouting, differentiation potential, cytokine secretion, telomere length and mtDNA copy number were analysed. All ADSC expressed CD73, CD90, CD105, while functional properties differed significantly among patients. A high BMI difference due to massive weight loss was negatively correlated with ADSC proliferation, migration and transmigration, while age, sex or weight loss method had a smaller effect. ADSC from female and younger donors and individuals after weight loss by increase of exercise and diet change had a higher activity. Telomere length, mtDNA copy number, differentiation potential and the secretome did not correlate with patient factors or cell function. Therefore, we suggest that factors such as age, sex, increase of exercise and especially weight loss should be considered for patient selection and planning of regenerative therapies.

Long-Term Clinical and Aesthetic Results of a Systematic Fat Transfer Protocol for Total Breast Reconstruction after Nipple-Sparing Mastectomy

BACKGROUND

Autologous fat transfer can be safely offered for total breast reconstruction after nipple-sparing mastectomy. The aim of this study was to extend a fat transfer protocol to smokers and compare the long-term results among them and irradiated and nonirradiated patients.

METHODS

One hundred seventeen breasts after nipple-sparing mastectomy were prospectively enrolled and stratified in group A (25 irradiated), group B (21 smokers), or group C (71 controls). A standardized fat transfer protocol was used. Data collected were patient demographics, surgery information, and aesthetic analysis. Continuous and categorical variables were analyzed with the Kruskal-Wallis test, and the Cohen Kappa test was used to test interrater variability for the aesthetic analysis.

RESULTS

Groups were homogeneous for demographics ( p > 0.05) but significantly different in number of fat transfer sessions ( p < 0.001), mean volume of the first two treatments ( p = 0.003), and mean total volume of injected fat ( p = 0.002). Volume, shape, position of the breast mound, inframammary fold, and scar location subscales obtained high score evaluations without a significant difference among groups ( p > 0.05), whereas skin texture subscale showed a lower score evaluation in group A ( p = 0.003). Although a significant difference for total subscales was worse in group A ( p = 0.004), the global score had a high rate evaluation in all groups ( p = 0.145). Interrater reliability showed substantial agreement among all categories.

CONCLUSION

Although further investigation is required, the authors confirm the efficacy of their fat transfer protocol for both irradiated and nonirradiated nipple-sparing mastectomy patients and propose its indication to smokers with comparable clinical and aesthetic results.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, II.

"Soft Tissue Reconstruction in Progressive Hemifacial Atrophy: Current Evidence and Future Directions"

BACKGROUND

Progressive Hemifacial Atrophy (PHA) is a rare disorder characterized by gradual unilateral soft tissue atrophy in the face, which may also include clinically significant degeneration of underlying muscle and bone. In recent years, there has been a growing body of evidence regarding different soft-tissue reconstructive strategies in PHA, and the impact of intervention timing on disease progression. This article provides a comprehensive synthesis of the latest evidence in order to guide optimal management.

METHODS

A comprehensive multi-database search was performed through April 2020 using relevant search terms to identify clinical studies. Outcomes, complications, disease- and patient-related indications pertaining to different soft-tissue reconstructive strategies in PHA were collected and critically appraised.

RESULTS

35 articles reporting on a total of 824 PHA patients were evaluated; 503 (61%) were managed by microvascular free flaps, 302 patients (37%) were managed by autologous fat grafts, and 19 (2%) by pedicled flaps. A detailed synthesis of outcomes is presented herein, as well as a comparative evaluation of different microvascular free-flap options.

CONCLUSION

Soft-tissue reconstruction in PHA remains an evolving field. Operative decision-making is often multifaceted, and guided by specific volumetric, aesthetic and functional deficiencies. Serial fat grafting is the primary modality utilized for patients with mild soft-tissue atrophy, while microvascular free flaps widely remain the treatment of choice for reconstruction of large volume defects. There exists a growing role of graft supplementation to improve fat graft survival, while recent evidence demonstrates that early intervention may help curb disease progression.

Association Between Fat Graft Retention and Blood Flow in Localized Scleroderma Patients: A Pilot Study

Background

Microcirculation plays a vital role in scleroderma physiopathology and the mechanism of fat survival.

Objective

This study aims to assess the blood perfusion change after fat grafting and evaluate the relationship between blood perfusion and fat graft retention in patients with localized scleroderma (LS).

Methods

A pilot study was conducted in patients with LS receiving autologous fat grafting (AFG). Fat graft retention measured by magnetic resonance imaging (MRI) analysis and blood flow perfusion measured by laser speckle contrast imaging 6 months postoperatively were noted. PUMC Localized Scleroderma Facial Aesthetic Index was used to assess the improvement of facial aesthetic impairment.

Results

The fat retention at the 6-month follow-up was 34.56 ± 11.89 percent. At the 6th month of follow-up, the relative blood perfusion at the lesion area was 115.08 ± 14.39 PU, significantly higher than 100.42 ± 10.62 PU at the pre-operation (p = 0.010). The blood perfusion at follow-up increased by an average of 1.15 ± 0.14 times before the operation. No association between the increase in the blood flow perfusions and fat graft retention was found (r = −0.082, p = 0.811).

Conclusion

Local blood perfusion in the lesion area relatively increased after AFG, but no direct relationship was found between fat retention and increased blood supply.

A Preliminary Exploratory Study of Autologous Fat Transplantation in Breast Augmentation With Different Fat Transplantation Planes

Background

Autologous fat transfer is common in breast augmentationor reconstruction. However, AFG recipient site in the breast for fat grafting has not been carefully investigated.

Methods

Forty female patients requiring breast augmentation with fat grafting were randomly assigned into two groups. The retromammary group received 2/3 fat into the retromammary space and the other 1/3 into the subcutaneous and retropectoral planes. The retropectoral group received 2/3 fat into the retropectoral plane and the other 1/3 into the subcutaneous and retromammary planes. The fat grafting result at 6 months was assessed by 3D laser surface scanning and then ultrasound. Any complications were recorded during follow-up. Samples from a patient who underwent fat grafting for 6 months was obtained and histological examination was conducted.

Results

No significant difference in the retention rate after 6 months was observed between the two groups (retromammary group: 35.9% ± 6.6; retropectoral group: 39.3% ± 5.1, p = 0.1076). The retromammary grouphad a higher incidence of oil cyst formation than the retropectoral group. Histological examination showed that there were more oil cysts and mac2 positive macrophage infiltration in the fat cells in retromammary group, while retropectoral group had more small-size adipocytes.

Conclusion

Although fat grafting into the retropectoral plane did not provide a superior fat graft retention rate, it did lower the incidence of complications. The retropectoral space show great potential to become a favorable recipient site.

Evolution of the Coleman Technique

Fat grafting is one of the most revolutionary surgical techniques of our century, which has changed the field of plastic surgery and regenerative medicine. Early reports of fat grafting date back to the late 19th century, but the results were unsatisfactory due to minimal graft retention. It wasn't until Sydney R. Coleman challenged the dogma and introduced a standardized approach to fat grafting after years of research and learning from experts across the world. The Coleman technique represents an evolutionary approach to fat grafting, with three main components: harvesting, refinement, and placement. The Coleman technique has been adopted and modified by surgeons around the world because it has allowed a reliable increase in fat graft survival through a standardized process. This article discusses the influencing factors and milestones that led to this world known technique, as well as Dr. Coleman's current practices, pearls, pitfalls, and lessons learned over the years. The knowledge of the true potential and usefulness of fat is in its infancy, with its regenerative potential becoming increasingly recognized. Current and future research will likely prove that autologous fat has many clinical applications beyond its well-known aesthetic and reconstructive benefits, and extending beyond the regenerative realm.

The General Registry of Autologous Fat Transfer: Concept, Design, and Analysis of Fat Grafting Complications

BACKGROUND

The American Society of Plastic Surgeons and The Plastic Surgery Foundation launched GRAFT, the General Registry of Autologous Fat Transfer, in October of 2015. This web-accessible registry addresses the need for prospective and systematic data collection, to determine the rates of unfavorable outcomes (complications) of fat grafting. Understanding and avoiding the factors that lead to complications can help establish safe practices for fat grafting.

METHODS

Data collected between October of 2015 and November of 2019 were summarized for age, sex, indications, processing techniques, and fat graft volume. Rates of complications for fat grafting to various anatomical areas were calculated.

RESULTS

The General Registry of Autologous Fat Transfer collected data on 7052 fat grafting procedures from 247 plastic surgery practices. The mean age of the patients in the registry was 51 years (range, 1 to 89 years), 94 percent were female, and 64 percent of the procedures were for aesthetic indications. Whereas the overall complication rate was low (5.01 percent), the complication rates for fat grafting to the breast and buttocks (7.29 percent and 4.19 percent, respectively) were higher than those for face and other areas (1.94 percent and 2.86 percent, respectively). Oil cysts (2.68 percent) and infections (1.64 percent) were the most common complications of breast fat grafting, whereas seroma (1.84 percent) and palpable mass (1.33 percent) were most common for fat grafting to buttocks. Palpable mass (0.54 percent) and infections (0.54 percent) were most common for fat grafting to face.

CONCLUSIONS

The General Registry of Autologous Fat Transfer provides a valuable tool for prospective tracking of fat grafting techniques and complications. Data collected in the registry show low rates of complications for all recipient areas treated with fat grafting.

CLINICAL RELEVANCE STATEMENT

GRAFT collects real world data on complications of autologous fat grafting procedures. The data collected over 4 years shows low rates of complications for fat grafting. The benchmarking tools available in GRAFT can help enhance techniques and safety of fat grafting.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Alternatively activated macrophages at the recipient site improve fat graft retention by promoting angiogenesis and adipogenesis

The inflammatory response mediated by macrophages plays a role in tissue repair. Macrophages preferentially infiltrate the donor site and subsequently, infiltrate the recipient site after fat grafting. This study aimed to trace host‐derived macrophages and to evaluate the effects of macrophage infiltration at the recipient site during the early stage on long‐term fat graft retention. In our novel mouse model, all mice underwent simulated liposuction and were divided into 2 groups. The fat procurement plus grafting (Pro‐Grafting) group was engrafted with prepared fat (0.3 ml). The pro‐Grafting+M2 group was engrafted with prepared fat (0.3 ml) mixed with 1.0 × 10⁶ GFP+M0 macrophages, and then, 2 ng IL‐4 was injected into the grafts on Day 3. In addition, 1.0 × 10⁶ GFP+M0 macrophages were injected into the tail vein for tracing in the Pro‐Grafting group. As a result, GFP+macrophages first infiltrated the donor site and subsequently infiltrated the recipient site in the Pro‐Grafting group. The long‐term retention rate was higher in the Pro‐Grafting+M2 group (52% ± 6.5%) than in the Pro‐Grafting group (40% ± 3.5%). CD34+ and CD31+ areas were observed earlier, and expression of the adipogenic proteins PPAR‐γ, C/EBP and AP2 was higher in the Pro‐Grafting+M2 group than in the Pro‐Grafting group. The host macrophages preferentially infiltrate the donor site, and then, infiltrate the recipient site after fat grafting. At the early stage, an increase in macrophages at the recipient site may promote vascularization and regeneration, and thereby improve the fat graft retention rate.

Experimental study on the influence of different aperture connectors on nanofat

BACKGROUND

Nanofat, as a derivative of adipose tissue, has gradually become a research hotspot in beauty and regenerative medicine. However, the nanofat preparation method has not yet been standardized; it remains unknown whether the aperture of the connector has any influence on the transplantation effect.

METHODS

Adipose tissue was mechanically emulsified into nanofat tissue through different connector apertures (1.0, 1.5, and 2.0 mm). Cell survival and apoptosis were measured using the volume of oil droplets, glucose transportation test, flow cytometry, cell counting kit-8 (CCK-8), wound healing assay, transwell migration assay, and fluorescence staining. The expression of adiponectin, GluT4, and PPAR-γ in nanofat-derived stem cells (NFSCs) was detected using quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

The fineness of nanofat tissue texture decreased with an increase in the aperture connector. The amounts of glucose transferred in the three groups (1, 1.5, and 2 mm) were 4.7 ± 0.894, 6.1 ± 1.026, and 6.9 ± 0.868 mmol/L, respectively. Flow cytometric analysis showed that the proportion of NFSCs in the 2.0 mm group was the highest (91.267±1.210%). Cell proliferation and migration abilities were stronger in the 1.5 and 2.0 mm groups. The numbers of late apoptotic and dead cells in the 2.0 mm group were significantly fewer than those in the two other groups. Expression levels of lipid-related genes were as follows: adiponectin > GluT4 > PPAR-γ in each component.

CONCLUSIONS

As nanofat is emulsified, the use of larger aperture connectors (2.0 mm) appeared to decrease the degree of adipocyte lysis and increase the biological activity of adipose tissue.

Unique hypoxia-tolerant subpopulations of adipose-derived stem cells: ITGB3+ cells

BACKGROUND

We found by accident that stem cells could still be isolated from adipose tissue stored for 14 days in sealed tubes, which was distinct from previous protocols. The morphology of these hypoxia-tolerant stem cells also differs from that of conventional adipose-derived stem cells (ADSCs). In this study, we aim to define the newly found subsets.

MATERIALS AND METHODS

Stem cells were isolated from adipose tissue that was aspirated immediately or stored for 14 days. The stem cells were then harvested for flowcytometric analysis and differentiation potentials. The expression of hypoxia-inducible factor 1 alpha (HIF-1α) was assayed to confirm the hypoxia-tolerant ability. RNA sequencing (RNA-seq) was performed to find the common signatures of the hypoxia-tolerant cells. The result of bioinformatics was tested by quantitative real-time reverse transcription-polymerase chain reaction (qPCR) and western blotting.

RESULTS

Certain subsets of ADSCs can be isolated from adipose tissue stored for 14 days. These survived cells were positive for CD90, CD105, and CD73 and showed multilineage differentiation potentials. The hypoxic condition was evidenced by up-regulation of HIF-1α for 2.0-fold changes (p < 0.05). The hypoxia-tolerant stem cells were distinct from multilineage-differentiating stress-enduring (Muse) cells, previously found stress-enduring stromal cells. RNA-seq suggested that integrin beta 3 (ITGB3) was highly expressed in hypoxia-tolerant subpopulations. The result was further confirmed at transcription and translation levels by qPCR and western blotting (mRNA: 2.9 ± 0.4, p < 0.05; protein: 1.5 ± 0.2, p < 0.05; respectively). The conventional ADSCs are positive for ITGB3, which implies that ITGB3+ cells are subpopulations of heterogeneous ADSCs.

CONCLUSIONS

Our study reveals the ITGB3⁺ subsets with potent hypoxia tolerance, which has significant implications for improving fat retention rates and curing obesity-related diseases.

Preoperative Short-Term High Carbohydrate Diet Provides More High-Quality Transplantable Fat and Improves the Outcome of Fat Grafts in Mice

BACKGROUND

Patients with a low body mass index may have inadequate high-quality adipose tissue for transplantation. The influence of high-energy diets on adipose tissue and graft retention remains unknown.

OBJECTIVES

We explored inguinal fat pad alternation in mice fed on a short-time high-fat diet (HFD) or a high-carbohydrate diet (HCD) preoperatively and the morphological and histological differences after transplantation.

METHODS

Mice were fed HFD (60% kilocalories from fat, 20% from carbohydrate), HCD (9.3% kilocalories from fat, 80.1% from carbohydrate), or normal (12% kilocalories from fat, 67% kilocalories from carbohydrate) diets for 2 or 4 weeks. Histological analyses were carried out following hematoxylin and eosin staining, and CD34 and proliferating cell nuclear antigen immunostaining. The uncoupling protein-1 (UCP-1) expression was determined by western blotting. Fat pads from each group were grafted into the dorsal region of the recipient mice and morphological and histological changes were determined 4, 8, and 12 weeks post-transplantation. Vascular endothelial growth factor α and platelet-derived growth factor α expression were determined using quantitative polymerase chain reaction.

RESULTS

The inguinal fat pad volume increased in the HFD and HCD groups. The presence of multilocular adipocytes in inguinal fat of HCD-fed mice, combined with the increased UCP-1 content, suggested adipocyte browning. HCD grafts showed higher volume retention and reduced oil cyst formation, possibly attributed to better angiogenesis and adipogenesis.

CONCLUSIONS

HCD enlarged adipose tissue and improved grafts survival rates, which may be due to the browning of fat before grafting and enhanced angiogenesis after grafting.

Autologous Fat Grafting to the Breast: An Educational Review

Autologous fat grafting (AFG) is a technique that is increasingly utilized in breast cosmetic and reconstructive surgery. In this procedure, fat is aspirated by liposuction from one area of the body and injected into the breast. The procedure and process of AFG has evolved over the last few decades, leading to more widespread use, though there is no standard method. Autologous fat grafting is generally considered a safe procedure but may result in higher utilization of diagnostic imaging due to development of palpable lumps related to fat necrosis. Imaging findings depend on surgical technique but typically include bilateral, symmetric, retromammary oil cysts and scattered dystrophic and/or coarse calcifications when AFG is used for primary breast augmentation. More focal findings occur when AFG is used to improve specific areas of cosmetic deformity, scarring, or pain following breast cancer surgery. As with any cause of fat necrosis, imaging features tend to appear more benign over time, with development of rim calcifications associated with oil cysts and a shift in echogenicity of oil cyst contents on ultrasound towards anechoic in some cases. This article reviews the AFG procedure, uses, complications, and imaging findings.

Platelet-Rich Fibrin in Fat Grafts for Facial Lipofilling: A Randomized, Controlled Split-Face Clinical Trial

Objective

Previous studies have reported that platelet-rich fibrin (PRF) may enhance the efficacy of fat grafts in facial lipofilling. However, these studies either lacked objective data or were not randomized, controlled trials. Thus, we aimed to objectively evaluate the efficacy of PRF in facial lipofilling.

Methods

A controlled, split-face, randomized trial (January 2018 to May 2019) based on 18 patients who underwent fat grafts for bilateral temple lipofilling was performed. Each patient received a combination of an autologous fat graft and PRF on one side and a fat graft combined with an equal volume of saline on the other side. The effects of PRF were evaluated by comparing the remaining bilateral fat graft volumes through a digital three-dimensional reconstruction technique. Improvements in the appearance and recovery time of each temple were assessed by both a surgeon and patients who were blinded to the treatment assignment. Complications were also recorded.

Results

Bilateral temple lipofilling showed no evidence of fat embolism, vascular/nerve injury, infection, massive edema, or prolonged bruising. Three-dimensional reconstruction data and the assessments from both the surgeon and patients revealed no significant differences in fat graft retention volume between the PRF-positive and PRF-negative lipofilling groups. However, recovery time in the PRF-positive lipofilling sites was significantly shortened compared with that of the PRF-negative lipofilling sites.

Conclusion

Facial filling with autologous fat grafts is effective and safe. Our results show that PRF does not markedly improve fat graft volume retention in the temple but significantly reduces postoperative recovery time.

Trial Registration Number

ChiCTR2100053663.

LRG-1 promotes fat graft survival through the RAB31-mediated inhibition of hypoxia-induced apoptosis

Autologous adipose tissue is an ideal soft tissue filling material, and its biocompatibility is better than that of artificial tissue substitutes, foreign bodies and heterogeneous materials. Although autologous fat transplantation has many advantages, the low retention rate of adipose tissue limits its clinical application. Here, we identified a secretory glycoprotein, leucine‐rich‐alpha‐2‐glycoprotein 1 (LRG‐1), that could promote fat graft survival through RAB31‐mediated inhibition of hypoxia‐induced apoptosis. We showed that LRG‐1 injection significantly increased the maintenance of fat volume and weight compared with the control. In addition, higher fat integrity, more viable adipocytes and fewer apoptotic cells were observed in the LRG‐1‐treated groups. Furthermore, we discovered that LRG‐1 could reduce the ADSC apoptosis induced by hypoxic conditions. The mechanism underlying the LRG‐1‐mediated suppression of the ADSC apoptosis induced by hypoxia was mediated by the upregulation of RAB31 expression. Using LRG‐1 for fat grafts may prove to be clinically successful for increasing the retention rate of transplanted fat.

Fat Grafting: Basic Science, Techniques, and Patient Management

In this review, a summary of the rich history of autologous fat grafting is provided, and a comprehensive summary of the science and theory behind autologous adipocyte transplantation, as well as the techniques commonly used is described. These include recipient site preparation, harvesting, processing, and engraftment. In addition, important considerations for preoperative and postoperative management are discussed to maximize graft retention. Special considerations in grafting to the breast, face, and buttocks are also summarized.

Oil Cyst Formation after Lower Blepharoplasty with Fat Grafts

BACKGROUND

Fat grafting is increasingly used as an adjuvant surgery to blepharoplasty to refill the volume loss of an aged face and promote cellular regeneration. Complications, such as hematoma, infection, seroma, and palpable mass, may occur. We collected the patients that underwent lower blepharoplasty combined with fat graft to evaluate the incidence of oil cyst formation in the lower eyelid and to identify risk factors.

MATERIAL AND METHODS

A retrospective review was performed of all patients who underwent lower or total blepharoplasty combined with fat graft at the authors' institution between January 2018 and June 2020. Complication rates were observed, and associations between preoperative variables and outcomes were assessed.

RESULTS

A total of 119 patients were included in the series (all bilateral, 238 eyelids). The average patient age was 54.88 ± 11.94 years, and the average grafted fat was 1.88 ± 1.0 mL. On a per-eyelid basis for all patients, the complication rate of oil cyst formation was 6.72% (16 of 238 eyelids). The occurrence of oil cyst formation was associated with hypertension (P = 0.012; adjusted odds ratio, 9.27; 95% confidence interval, 1.62-52.99) and diabetes mellitus (P = 0.005; adjusted odds ratio, 14.02; 95% confidence interval, 2.22-88.45), but not associated with anticoagulants use (P = 0.931), age (P = 0.784), sex (P = 0.317), or fat volume (P = 0.215). The mean interval between the fat graft procedure and oil cyst noted was 236.5 ± 118.9 days.

CONCLUSIONS

Oil cyst in lower eyelid can be defined as a palpable, firm, and persistent subcutaneous cystic lesion found postoperatively in any size during physical examination. The complication rate of oil cyst formation occurring after lower blepharoplasty with autologous fat grafting is 6.72%. Hypertension and diabetes mellitus maybe are risk factors of oil cyst formation. Steroid injection, needle capsulotomy, liposuction, and excision are safe and effective treatments. Reduce surgical trauma by diminishing anterior lamina trauma and capsulopalpebral fascia repair might decrease the complication rate of oil cyst formation.Transconjunctival lower blepharoplasty with fat graft or 2-stage surgery may be a choice to prevent oil cyst formation.

Autologous fat transfer for hand rejuvenation: systematic review on technique and outcome

Background

Age-related changes to the dorsum of the hand present as dyschromia, soft-tissue atrophy, and volume loss, resulting in wrinkles and prominent deep structures. Volume augmentation by means of autologous fat transfer (AFT) is one of the options to rejuvenate the hand; theoretically, autologous fat is the ideal filler because of durability and biocompatibility.

Objective

This systematic review aims to summarize and describe the current evidence on the technique, effectiveness, and safety of AFT in hand rejuvenation.

Methods

Three major databases, PubMed, Embase, and Web of Science, were systematically searched up to November 2020 for studies reporting on AFT and hand rejuvenation.

Results

A total of 10 articles were included, reporting on a total of 320 patients treated by AFT to improve the aesthetic appearance of the dorsum of the hand. Some degree of postoperative oedema was present in nearly all patients. Other complications were infection (0.67%), cysts/irregularities (1.3%), temporary dysesthesia (5.3%), and ecchymosis (7%). There were no major complications. Of all patients, 97.6% self-reported to be satisfied with the result.

Conclusions

Overall, by combining the current evidence, AFT is considered a promising and safe technique to rejuvenate the aging hand with very high patient satisfaction. Future research, using validated patient questionnaires, objective volumetric measurements, and longer follow-up, is needed to confirm these results.

Level of Evidence

3

Fragmented Fat Transfer for Massive Weight Loss Gluteal Contouring

SUMMARY

A recently introduced novel fragmentation technique has made it possible to convert fat tissue from apronectomy into large-scale viable lipograft, providing a glimpse of an alternative to traditional liposuction and its harvesting limitations. The purpose of this study was to assess the initial clinical evidence on fragmented fat transfer to restore volume and enhance deflated gluteal contours in a sample of massive weight loss patients. The authors retrospectively reviewed medical records of 20 women who received autologous buttock fat grafts that were harvested and fragmented following belt lipectomies and/or fleur-de-lis abdominoplasties. The average total volume subcutaneously grafted into the buttocks was 720 ml (bilateral), ranging from 500 ml to 960 ml. No local gluteal complications, such as seroma, infection, fat necrosis, or subcutaneous nodulations, were reported. Photographic observation of postoperative results over a 6- to 14-month follow-up period showed clear enhancement of body contouring in all patients, especially in those in whom fat transfer was combined with circumferential lifts. Fat fragmentation has proved useful and effective in providing great amounts of viable fat graft in a safe, simple, and reproducible technique without noticeable complications. The method eliminates the organic response to the insult of liposuction while using the entirety of formerly discarded apronectomy tissue to provide fine, transferable, autologous fat without increasing operative time. Although preliminary, the authors' clinical findings with this new technique support further studies of fragmented fat as an alternative to liposuction in gluteal fat grafting. Additional potential applications, including in wound healing and regenerative medicine, are worth exploring. .

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Clinical Application of Stromal Vascular Fraction Gel in Temple Augmentation Using Deep Injection and Shallow Pave Filling

BACKGROUND

Temporal hollowing is an early sign of aging, and many techniques comprising the injection of fillers into the temporal fossa to correct this hollowing have been described.

OBJECTIVE

To assess the safety of a new technique in which stromal vascular fraction gel is used for temporal hollowing.

METHODS

Thirty-three patients with temporal hollowing were corrected with the aforementioned gel using deep injection and shallow pave filling at the Department of Plastic and Reconstructive Surgery, Guangdong Women and Children Hospital, China, between January 2017 and April 2021. This gel was injected into the double plane via a needle and cannula by the same cutaneous access points to prevent severe vascular injury. Improvement was evaluated by self-assessment, the Hollowness Severity Rating Scale (grade range, 0-3; lower grades represent minimal hollowness), and a satisfaction survey.

RESULTS

Self-assessment questionnaire (6 questions) results were satisfactory; 44 temples (67%) demonstrated more than 2 grades of magnitude of clinical improvement. Thirty-one patients (94%) were satisfied with their outcomes; the complaint ratio was low.

CONCLUSION

The high satisfaction rate of patients treated using the stromal vascular fraction gel by deep injection and shallow pave filling suggests that this technique is simple, effective, and safe.

LEVEL OF EVIDENCE IV

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 .

Autologous fat grafting as a minimally invasive technique to avoid cochlear implant extrusion

OBJECTIVES

Infection of the skin-muscle flap is one of the most severe risks of cochlear implantation. The aim of this paper is to describe a novel and minimally invasive procedure to avoid cochlear implant (CI) extrusion.

METHODS

A 79-year-old woman with severe comorbidities developed a pressure injury of the skin-muscle flap overlying the CI receiver/stimulator (R/S) nine years after surgery. Skin thinning and failure of conventional pressure injury management led the patient to a high risk of CI extrusion. Therefore, she underwent a single procedure of autologous fat grafting under local anesthesia to increase scalp thickness and vascularization over the CI R/S.

RESULTS

Within one month, complete healing of the pressure injury was observed, and the patient was able to safely use her CI. No further signs of infection and skin deterioration were detected at the 15-months follow-up.

DISCUSSION

Fat grafting has been proven to promote neoangiogenesis and tissue regeneration. To the best of our knowledge, this is the first report of fat grafting utilized in the skin-muscle flap area to avoid incipient CI R/S extrusion.

CONCLUSION

The described case demonstrates the efficacy of this salvage procedure to avoid major surgery and the additional costs related to CI reimplantation.

Investigation of Autologous Fat Transfer in Capsule Formation around Silicone Implants in a Rat Model

BACKGROUND

In this experimental study, the authors investigated whether fat placement in the pocket during implant insertion affects capsule formation.

METHODS

Twenty albino Wistar rats, 400 g each, were used. The rats were divided into two groups, A and B, of 10 rats each. At the dorsum of each rat, four pockets (2 × 2 cm each) were dissected, two left and two right of the midline. In each pocket, a 1 × 1 × 1.5-cm silicone implant was inserted. In the two left pockets, only silicone implants were placed (control). In the two right pockets, 0.4 ml of fat was injected around the implant. Animals in group A were killed 2 months postoperatively, and those in group B were killed 4 months postoperatively. The implants were dissected with the capsule and sent for histopathologic examination.

RESULTS

The data of the fat transfer group was compared with control in groups A and B. Capsule thickness, neovascularization, myofibroblast layer thickness, and mast cell population demonstrated no statistically significant difference in either group A (p = 0.385, p = 0.862, p = 0.874, and p = 0.210, respectively) or group B (p = 0.338, p = 1.000, p = 0.288, and p = 0.344, respectively). Inflammation was statistically significantly less (p = 0.07) at 4 months (group B) in the fat transfer group compared to the control group. Likewise, cellularity was statistically significantly less (p = 0.019) at 4 months for the fat transfer group compared with the control group.

CONCLUSION

Fat injection in the pocket during implant placement may reduce inflammation and cellularity of capsules and predispose to faster capsule maturation.

CLINICAL RELEVANCE STATEMENT

PLEASE PROVIDE 1- TO 2-SENTENCE STATEMENT.

Autologous Fat Grafting as Treatment of Postmastectomy Pain Syndrome: A Randomized Controlled Trial

BACKGROUND

Postmastectomy pain syndrome is a common and disabling side effect of breast cancer treatment. Medical treatment seems to be insufficient for a considerable proportion of patients. Fat grafting has shown promise in relieving pain from postmastectomy pain syndrome, but no randomized clinical trial comparing fat grafting to a sham operation has been performed to date. The authors' objective was to compare the effect of fat grafting compared to a sham operation for treating postmastectomy pain syndrome.

METHODS

The authors conducted a single-center, double-blind, randomized clinical trial with two arms between October of 2017 and September of 2020. The authors assessed four patients suffering from postmastectomy pain syndrome for inclusion. The intervention group received scar-releasing rigottomy and fat grafting to the area of pain. The control group received scar-releasing rigottomy and a placebo of saline solution. The primary outcome was the degree of pain measured using the Numerical Rating Scale. The secondary outcomes were the degree and quality of neuropathic pain (Neuropathic Pain Symptom Inventory) and quality of life (36-Item Short-Form Health Survey). Follow-up was 6 months.

RESULTS

Thirty-five participants completed follow-up: 18 participants in the intervention group and 17 in the control group. The authors detected no statistically significant changes in average and maximum pain or neuropathic pain. Regarding quality of life, the control group reported a statistically significant improvement in emotional problem parameters, whereas the intervention group reported a deterioration. The authors observed no serious adverse effects.

CONCLUSION

The authors did not find evidence to support that fat grafting is superior to a placebo when treating postmastectomy pain syndrome.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, I.

Cosmetic Breast Augmentation Using Power-Assisted Liposuction and Lipofilling: A Prospective Study

INTRODUCTION

Autologous fat transfer is becoming a more and more widespread procedure in aesthetic breast surgery. Power-assisted technology produces oscillating reciprocal movements of cannula tip, which reproduce the motion of the operator's arm with lower amplitude. The power-assisted mechanism can be applied to the fat liposuction and injection phases. The aim of this study is to report our experience on autologous fat transfer in primary cosmetic breast augmentation using power-assisted liposuction and lipofilling (PALL), our surgical technique and on long-term cosmetic results, and patient-reported outcomes.

MATERIALS AND METHODS

A prospective observational study was performed including all patients who underwent PALL cosmetic breast augmentation. Collected data included patient's age, BMI, mean liposuction and fat injection volume, mean operating time, postoperative complications, mean number of grafting procedures required to achieve the desired outcome, cosmetic results and patient satisfaction.

RESULTS

A total of 43 patients were included with a mean follow-up of 13.32 months. Mean liposuction and injection volumes were 1884.54 mL and 399.03 mL, respectively. Mean number of grafting procedures was 1.27. With respect to aesthetic outcomes, the mean score for breast volume, shape, symmetry and donor site shape was 4.38, 4.22, 4.27 and 4.42, respectively. Regarding patient satisfaction, the mean score for breast volume, shape, symmetry and donor site shape was 4.22, 5, 5 and 4.77, respectively.

CONCLUSION

The current study is the first prospective report on primary cosmetic breast augmentation using PALL. Although our sample of patients is limited, our results showed that PALL primary breast augmentation is an efficient procedure, which leads to satisfactory results for both patients and surgeons.

LEVEL OF EVIDENCE IV

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 .

Breast Reconstruction by Exclusive Lipofilling after Total Mastectomy for Breast Cancer: Description of the Technique and Evaluation of Quality of Life

Background: The objective of this work was to describe the technique of exclusive lipofilling in breast reconstruction after total mastectomy, to evaluate the satisfaction and quality of life of the patients, and to explore current literature on the subject. Methods: We conducted a retrospective observational multicentric study from January 2013 to April 2020. The modalities of surgery, esthetic result, and patient satisfaction were evaluated with the breast reconstruction module of BREAST-Q. Results: Complete data were available for 37 patients. The mean number of sessions was 2.2 (standard deviation 1.1), spread over an average of 6.8 months (SD 6.9). The average total volume of fat transferred was 566.4 mL. The complication rate was 18.9%. No severe complication was observed (Clavien–Dindo 3/4). Two patients were diagnosed with recurrence, in a metastatic mode (5.4%). The average satisfaction rate was 68.4% (SD 24.8) for psychosocial well-being and 64.5% (SD 24.1) for sexual well-being. The satisfaction rate was 60.2% (SD 20.9) for the image of the reconstructed breast and 82.7% (SD 21.9) for locoregional comfort. Conclusions: Breast reconstruction by exclusive lipofilling after total mastectomy provides satisfactory quality of life scores. The simplicity of the surgical technique and equipment required, and the high satisfaction rate confirm that lipofilling should be included in the panel of choice of breast reconstruction techniques.

Renal puncture access using a blunt needle: proposal of the blunt puncture concept

Purpose

Severe haemorrhage in percutaneous nephrolithotomy (PCNL) is an alarming event, and preventing injury to renal major vessels is a challenge. We evaluated the efficiency of a blunt needle in renal puncture procedures.

Methods

We first retrospectively reviewed the embolization images of post-PCNL patients to analyse the types of arteries injured, which were considered target arteries. Then, either a blunt needle or a conventional needle was used to directly puncture target arteries in ex vivo porcine kidneys and to establish renal access ex vivo and in vivo. The primary outcome was the incidence of target artery injuries, which were observed by digital subtraction angiography, nephroscopy and 3-dimensional endocasts. The secondary outcome was the rate of excreted fluid per access.

Results

The segmental and interlobar arteries were the most common types of injured arteries that needed to be embolized after PCNL. When these arteries were punctured directly, blunt needles reduced injury (1/20 vs. 16/20; OR 4.750; 95% CI 1.966–11.478; P < .001) by 76% compared to injuries induced by conventional needles. Moreover, the blunt needle group also had a significantly lower incidence of these arteries’ injuries ex vivo due to renal puncture and yielded a lower rate of excreted fluid in ex vivo and in vivo renal puncture procedures.

Conclusion

A blunt needle for renal puncture can be effective in reducing injury to renal major arteries and the accompanying haemorrhage. We propose the concept of blunt puncture, which may be a promising method for achieving safe renal access in PCNL.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-021-03927-8.