Does Stromal Vascular Fraction Ensure a Higher Survival in Autologous Fat Grafting for Breast Augmentation? A Volumetric Study Using 3-Dimensional Laser Scanning

Survival Mechanisms and Retention Strategies in Large-Volume Fat Grafting: A Comprehensive Review and Future Perspectives

INTRODUCTION

Large-volume fat grafting is emerging as a promising technique in plastic and reconstructive surgery. However, the unpredictable graft volume retention rate remains a critical challenge. To address this issue, we need a profound understanding of the survival mechanisms following large-volume fat transplantation. This review summarizes known survival mechanisms and strategies to enhance graft retention.

METHODS

This review comprehensively examines the current literature on the survival mechanisms and retention strategies in large-volume fat grafting. A thorough literature search was conducted using PubMed, Medline and Google Scholar databases, focusing on studies published from 2009 to 2023.

CONCLUSION

In the current research on fat survival mechanisms, few have focused on large-volume fat grafting. This review provides an overview of the survival mechanisms specific to large-volume fat grafting and identifies a survival pattern distinct from that of small-volume fat grafting. Additionally, we have summarized existing strategies to improve graft retention across five stages (harvesting, processing, enrichment, grafting and post-graft care), analyzed their advantages and disadvantages and identified some of the most promising strategies.

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.

Elderly Women Have a Higher Survival Rate of Grafted Donor Fat than Do Young Women Under the Influence of Low Estrogen Conditions

BACKGROUND

Fat grafting is widely used in breast reconstruction and aesthetic plastic surgery. However, the success rate and effects of fat grafting, especially in elderly female donors, are observed. This study aimed to explore the difference in the survival rate of donor fat from elderly women and young women in fat grafting.

METHODS

We collected adipose tissue samples from two healthy Chinese women: a young woman and an elderly woman. In addition, adipose tissue samples were collected from female nude mice in four experimental groups-CON-Y, CON-O, OVX-Y, and OVX-O-after fat transplantation. Grafts were harvested, weighed, and subjected to assessment of histology and angiogenesis.

RESULTS

An ovariectomy model was successfully established to validate the effect of low estrogen levels on fat grafting results. Due to the influence of low estrogen levels, the graft survival rate of donor site fat was significantly higher in elderly women than in young women, accompanied by a lesser degree of angiogenesis. Low estrogen levels led to adipocyte hypertrophy, which may be related to decreased AQP-7 expression.

CONCLUSIONS

AQP-7 downregulation due to low estrogen levels induces adipocyte hypertrophy, and donor fat from elderly women exhibits a higher survival rate after fat transplantation.

LEVEL OF EVIDENCE V

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 .

Effectiveness and Safety of Different Methods of Assisted Fat Grafting: A Network Meta-Analysis

OBJECTIVE

Numerous studies have proposed the utilization of stromal vascular fraction (SVF), adipose-derived stem cells (ADSCs), and platelet products as auxiliary grafting techniques to improve the survival rate of fat grafts. This study aimed to evaluate the efficacy and safety of various fat grafting methods since 2010 through a network meta-analysis, aiming to identify the most effective technique for fat grafting.

METHODS

Clinic trials on assisted fat grafting were searched from Pubmed, Embase, Web of Science, and the Cochrane Library, spanning the period from January 1, 2010 to March 2024. The risk of bias in the included trials was meticulously assessed using the Cochrane risk of bias tool. The survival rate of fat grafts served as the primary evaluation metric for effectiveness, while complications were employed as the indicator for safety.

RESULTS

The study incorporated 31 clinic trials, involving a total of 1656 patients. The findings indicated that the survival rate with assisted fat grafting significantly surpassed that of simple fat grafting (SUCRA, 10.43%). Notably, ADSC-assisted fat grafting exhibited the highest survival rate (SUCRA, 82.17%), followed by Salvia miltiorrhiza (SM)-assisted fat grafting (SUCRA, 69.76%). In terms of safety, the most prevalent complications associated with fat grafting were fat sclerosis and fat necrosis. Adc-assisted fat grafting was correlated with the lowest incidence of complications (SUCRA, 41.00%), followed by simple fat grafting (SUCRA, 40.99%). However, PRP-assisted (SUCRA, 52.86%) and SVF-assisted fat grafting (SUCRA, 65.14%) showed higher complication rates.

CONCLUSION

Various methods of assisted fat grafting can significantly enhance the survival rate, but they often fail to effectively mitigate the incidence of complications. Compared to other methods, adipose mesenchymal stem cells-assisted fat grafting consistently yielded a higher survival rate of grafts and fewer complications. Consequently, this approach represents a relatively effective method for assisting in fat grafting at present.

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 .

Comparative Efficacy and Safety of Cell-Assisted and Conventional Lipotransfer in Facial Filling: A Systematic Review and Meta-Analysis

PURPOSE

We aim to compare the efficacy and safety of cell-assisted lipotransfer (CAL) and conventional lipotransfer (CLT) in facial filling.

METHODS

The PubMed and Embase databases were searched for relevant publications until February 2023. All studies evaluating the efficacy and safety of cell-assisted and conventional lipotransfer in facial filling were included. We calculated pooled standardized mean difference (SMD) and 95% CIs for continuous outcomes and pooled risk ratio (RR) with 95% CIs for binary outcomes. The Cochrane's Risk of Bias Tool and the Newcastle-Ottawa Scale (NOS) were used to evaluate the quality of studies.

RESULTS

A total of 15 studies with 737 patients were included in this analysis. The fat survival rate and patient satisfaction rate were significantly higher in the CAL group compared to the CLT group (SMD: 3.04, 95% CI 2.09-3.99; RR: 1.34, 95% CI 1.08-1.67). However, no significant difference in complication rates (RR: 0.95, 95% CI 0.50-1.81) and a lower secondary operation rate in the CAL group (RR: 0.52, 95% CI 0.03-0.82) were observed. No obvious publication bias was observed in the funnel plot (Egger's P values = 0.084 and 0.403).

CONCLUSIONS

Based on the pooled results, we tentatively conclude that CAL may have superior fat survival rate and satisfaction rate compared to CLT in facial filling, without compromising patient safety. However, the majority of the included studies were observational studies with small sample sizes. Future research should focus on investigating the long-term efficacy and safety of these techniques.

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 .

Volume retention rate after breast autogenous fat grafting and related influencing factors: A systematic review and meta-analysis

The volume retention of breast autologous fat grafting is unpredictable, and the volume retention rate and related influencing factors have not been systematically reviewed. Therefore, this systematic review and meta-analysis aimed at evaluating the volume retention rate and related influencing factors of breast autologous fat grafting, which is for reconstructive or esthetic purposes. Literature search was conducted using the PubMed, Embase, Cochrane Library, and Web of Science databases from inception of study to December 2022. Sensitivity analysis was performed for all outcomes. Begg's test was performed to test publication bias. Subgroup analysis was performed based on population, method of fat preparation, method of volume measurement, number of fat grafting, and injected fat grafting volume. A total of 25 studies were included in this systematic review and meta-analysis. The follow-up time ranged from 3 to 36 months. Results showed that the pooled volume retention rate at the latest follow-up point was 54% [95% confidence interval (CI): 48.5%-59.5%]. Based on the fat preparation methods, the pooled rate was 51.5% (95%CI: 41.5%-61.5%) for centrifugation, which was higher than that for sedimentation [38.7% (95%CI: 30.9%-46.5%)]. In addition, the enrichment of stromal vascular fraction obtained after centrifugation was found to be associated with higher volume retention rate (weighted mean difference: 17.36, 95%CI: 8.84-25.87). Our findings may provide guidance for evaluating the volume retention rate of breast autologous fat grafting in clinical settings. Further studies are needed to verify our findings.

Evaluating the quality of studies reporting on clinical applications of stromal vascular fraction: A systematic review and proposed reporting guidelines (CLINIC-STRA-SVF)

Background

The stromal vascular fraction (SVF) has been widely explored in a number of therapeutic applications in several specialties. Its therapeutic potential is being increasingly demonstrated, although its mechanism of action is still unclear.

Objective

To evaluate the quality of studies reporting on clinical applications of SVF.

Method

This is a systematic literature review that followed the PRISMA guidelines with the search of the studies from December 1, 2012, to December 1, 2022, in the following databases: MEDLINE, LILACS and EMBASE. The level of evidence of the studies was assessed using the GRADE system, and the rigor used in the publication of the results was assessed in relation to adherence to the guidelines indicated by the EQUATOR Network Group. The CLINIC - STRA-SVF reporting guideline was developed after the completion of this systematic review.

Results

A total of 538 articles were found, and 77 articles were selected after reading the titles and abstracts and removing duplicates. Then, 15 studies were removed for not meeting the inclusion criteria, leaving 62 studies. The CLINIC - STRA-SVF was developed and consists of 33 items and two tables.

Conclusion

There is scientific evidence, although mostly with a low level of evidence, that the use of SVF in clinical applications is safe and effective. The information published in these studies should be standardized, and the CLINIC - STRA-SVF reporting guideline proposed in this study may assist in the design, conduct, recording and reporting of clinical trials and others clinical studies involving the SVF.

A Study on Breast Augmentation Using Fat Grafting With Stromal Vascular Fraction

BACKGROUND

Stromal vascular fraction (SVF) and fat grafting are emerging alternatives to implants for breast augmentation. However, the lack of controlled clinical data has led to conflicting results regarding the effectiveness of surgical treatments. This study aimed to identify the key factors affecting the outcomes of fat grafting with SVF and to recognize novel methods to improve the retention rate.

PATIENTS AND METHODS

In total, 384 women underwent breast augmentation using fat grafting with SVF. The patients were preoperatively and postoperatively managed and recalled for follow-up at 3, 6, and 18 months.

RESULTS

The average volume of the injection in the left breast was 162.35 mL (range, 50-260 mL). The postoperative retention rates were 78.65% in 384 patients at 3 months, 77.17% in 273 patients at 6 months, and 77.48% in 102 patients at 18 months. The retention rates were compared based on the number of SVF cells; patients with more than 60 million cells had a retention rate of 70.77%, and those with less than 60 million cells had a retention rate of 85.60% at 18 months. The retention rates at the 18-month follow-up were 65.62% and 85.09% in stiff and soft breasts, respectively. A higher number of cells in the SVF was associated with a greater retention volume, and the retention volume was greater in patients with soft breasts.Given the higher use of the right arm, after 18 months of the surgery, the retention rate of the right breast (60.35%) was lower than that of the left breast (77.48%) ( P < 0.05; t = -13.199).

CONCLUSIONS

Limiting arm movement, increasing the number of cells in the SVF, and improving the skin tension might enhance the retention rate in patients undergoing breast augmentation.

“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.

The efficacy of cell-assisted versus conventional lipotransfer: A systematic review and meta-analysis

Autologous lipotransfer is an essential component of soft tissue reconstruction. However, it is not widely applied or accepted by surgeons due to its unstable survival rate and uncertain efficacy. The cell-assisted fat transfer (CAL) is a promising technique that increases the fat survival rate. However, it is controversial based on various clinical studies. Here, we assessed the fat survival and complication rates of CAL, compared to the conventional autologous lipotransfer. To conduct our research, two reviewers independently screened related articles published in Medicine (via PubMed), EMBASE, Cochrane Library, and Web of Science. The combined effect estimates for efficacy evaluation was performed by the Review Manager software (RevMan 5.4.1). In total, 14 articles were included in our analysis (n = 722). Based on our analysis, the survival rate of the fat graft in CAL was significantly higher than the conventional fat grafting group (non-CAL group) (SMD = 2.81, 95%CI [1.54, 4.08], P < 0.01). In the subgroup, the fat retention of CAL in the facial filling was higher than the conventional one (SMD = 3.01, 95%CI [1.68, 4.33], P < 0.01). After breast augmentation, however, the difference between the experimental and control group was not statistically significant (SMD = 1.80, 95%CI [-0.31, 3.91], P = 0.09). Moreover, the CAL group exhibited comparable complications as the non-CAL group. Based on our analysis, the CAL group was significantly better than the conventional lipotransfer in terms of fat survival, particularly, during facial filling. However, it failed to reduce the complication rate, compared to the non-CAL group.

Fat Grafting With Expanded Adipose-Derived Stromal Cells for Breast Augmentation: A Randomized Controlled Trial

BACKGROUND

The main challenge with fat grafting is loss of some of the graft to postsurgery resorption. Previous studies suggest that adipose-derived stromal cells (ASCs) can improve the volume retention of fat grafts but there is a lack of randomized trials to support the use of ASCs in clinical practice.

OBJECTIVES

This trial aimed to investigate whether ASCs improve fat graft volume retention in patients undergoing breast augmentation with lipofilling.

METHODS

This was a double-blind, randomized controlled trial of breast augmentation with ASC-enriched fat grafting. Healthy women aged 30 to 45 years were enrolled. First, the participants underwent liposuction to obtain fat for culture expansion of ASCs. Then, the participants were randomly assigned to undergo a 300- to 350-mL breast augmentation with ASC-enriched fat grafting (10 × 106 ASCs/mL fat graft) to 1 of their breasts and placebo-enriched fat grafting of identical volume to the contralateral breast. The primary outcome was fat graft volume retention after a 1-year follow-up measured with MRI. The trial is registered at www.clinicaltrialsregister.eu (EudraCT-2014-000510-59).

RESULTS

Ten participants were included in the trial; all completed the treatment and follow-up. No serious adverse events occurred. Fat graft volume retention after 1 year was 54.0% (95% CI, 30.4%-77.6%) in the breasts treated with ASC-enriched fat grafting (n = 10) and 55.9% (95% CI, 28.9%-82.9%) in the contralateral breasts treated with placebo-enriched fat grafting (n = 10) (P = 0.566).

CONCLUSIONS

The findings of this trial do not support that ASC-enriched fat grafting is superior to standard fat grafting for breast augmentation.

LEVEL OF EVIDENCE: 2

Preliminary report of de novo adipogenesis using novel bioabsorbable implants and image evaluation using a porcine model

Our bioabsorbable poly-l-lactic acid (PLLA) mesh implants containing collagen sponge are replaced with adipose tissue after implantation, and this is an innovative method for breast reconstruction. In this preliminary study, we investigated the formation of adipose tissue and evaluated the process via multimodal images in a porcine model using an implant aggregate to generate the larger adipose tissue. The implant aggregate consists of PLLA mesh implants containing collagen sponge and a poly-glycolic acid woven bag covering them. We inserted the implant aggregates under the porcine mammary glands. Magnetic resonance imaging (MRI), ultrasonography (USG), and 3-dimensional (3D) surface imaging and histological evaluations were performed to evaluate the formation of adipose tissue over time. The volume of the implant aggregate and the formed adipose tissue inside the implant aggregate could be evaluated over time via MRI. The space within the implant aggregate was not confirmed on USG due to the acoustic shadow of the PLLA threads. The change in volume was not confirmed precisely using 3D surface imaging. Histologically, the newly formed adipose tissue was confirmed on the skin side of the implant aggregate. This implant aggregate has the ability to regenerate adipose tissue, and MRI is an appropriate method for the evaluation of the volume of the implant aggregation and the formation of adipose tissue.

Breast Reconstruction- Developing a Volumetric Outcome Algorithm

Postoperative loss of breast volume represents a significant parameter for outcome evaluation of breast reconstruction. Breast volume broadly varies- depending of reconstruction method as well as surgical differences. A structural pattern of breast volume loss provides an essential parameter for preoperative design, helps to reduce postoperative breast asymmetry rate and thereby the need for reoperation. Therefore we hereby compare volume change of the three main reconstruction techniques: autologous flap-based, prosthesis-based and autologous fat transplantation breast reconstruction. LEVEL OF EVIDENCE V: 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 .

Trends in Breast Augmentation Research: A Bibliometric Analysis

BACKGROUND

Breast augmentation is one of the most demanded procedures in plastic surgery and one of the most commonly performed by plastic surgeons. However, a bibliometric analysis of breast augmentation has not been published in recent years. The current study aimed to use a bibliometric analysis to conduct a qualitative and quantitative evaluation of breast augmentation research and provide the research trends and hotspots in this field.

METHODS

Publications on breast augmentation research were extracted from the Web of Science core collection database. VOSviewer 1.6.18 was used to assess co-authorship, co-occurrence, citation of countries, institutions, authors, and journals, as well as hotspot keywords.

RESULTS

On February 8, 2022, 4637 records of breast augmentation research published from 1985 to 2021 were collected. The bulk of the retrieved studies were original research articles (n = 2235, 48.20%). A total of 1053 (22.71%) papers were open access. The annual publication output increased annually. The USA was the driving force in this field and had a strong academic reputation. The top-contributing institution was the University of Texas MD Anderson Cancer Center (2.37%, with 110 publications). Plastic and reconstructive surgery (998 publications, 21.52%) published the most research in this field and was also the most frequently co-cited journal (22,351 citations, total link strength (TLS): 409,301). Clemens MW (68 publications, 1.47%) was the most prolific author, and Spear SL (1456 citations, TLS: 27,231) was the most frequently co-cited author. The research hotspots included the following four aspects: safety and effectiveness of breast implants, implant-based breast reconstruction, breast cancer incidence after breast implantation, and breast implant-associated anaplastic large-cell lymphoma (BIA-ALCL). The research trends were BIA-ALCL, implant-based breast reconstruction, BREAST-Q, acellular dermal matrix, capsular contracture, and autologous fat grafting.

CONCLUSION

The present study provides a panoramic view of breast augmentation research in plastic and reconstructive surgery. This novel comprehensive bibliometric analysis can help researchers and nonresearchers alike to rapidly identify the potential partners, research hotspots, and research trends within their areas of interest.

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 .

High-Density Fat Grafting Assisted Stromal Vascular Fraction Gel in Facial Deformities

Autologous fat grafting is commonly used for soft tissue augmentation and reconstruction, this technique is limited by a high rate of graft absorption. The stromal vascular fraction gel (SVF-gel) grafting for facial volume augmentation can exert a positive effect on skin rejuvenation, but its major limitation is the low rate of conversion of Coleman fat. The purpose of our study was to investigate a novel surgery using performing high-density fat in combination with SVF-gel in the treatment of hemifacial atrophy, or Romberg diseases. From October 2017 to October 2019, 13 patients with hemifacial atrophy underwent high-density fat transfer with SVF-gel injection. The outcome was determined by the difference in presurgery and postsurgery FACE-Q modules (FACE-Q conceptual framework: 1, Satisfaction with Facial Appearance; 2, Health-Related Quality of Life; 3, Negative Sequelae; 4, Satisfaction with Process of Care), which were designed as patient-reported outcome instrument to evaluate the unique outcomes of patients undergoing facial cosmetic procedures.

The excellent cosmetic results were observed during follow-up periods, with no adverse events was seen in the treatment group. All patients showed improvements in facial augmentation and contour. In patients with facial volume loss, high-density fat transfer with SVF-gel facial injection resulted in significantly higher improvement scores and better patient satisfaction. The patient-reported FACE-Q modules presurgery and postsurgery results showed statistically significant improvement (P < 0.05). This high-density fat in combination with SVF-gel is an effective method of correcting the facial volume loss that leave no complications during follow-up, having a satisfactory volumization effect. This could largely facilitate the clinical utilization of fat.

Update on the Basic Science Concepts and Applications of Adipose-Derived Stem Cells in Hand and Craniofacial Surgery

SUMMARY

Adipose-derived stem cell therapy offers plastic surgeons a novel treatment alternative for conditions with few therapeutic options. Adipose-derived stem cells are a promising treatment because of their broad differentiation potential, capacity for self-renewal, and ease of isolation. Over the past decade, plastic surgeons have attempted to harness adipose-derived stem cells' unique cellular characteristics to improve the survival of traditional fat grafting procedures, a process known as cell-assisted lipotransfer. However, the full implications of cell-assisted lipotransfer in clinical practice remain incompletely understood, stressing the urgent need to assess the scientific evidence supporting adipose-derived stem cell-based interventions. Furthermore, with the strict regulatory climate surrounding tissue explantation therapies, reviewing the safety and efficacy of these treatments will clarify their regulatory viability moving forward. In this report, the authors provide a comprehensive, up-to-date appraisal of best evidence-based practices supporting adipose-derived stem cell-derived therapies, highlighting the known mechanisms behind current clinical applications in tissue engineering and regenerative medicine specific to plastic and reconstructive surgery. The authors outline best practices for the harvest and isolation of adipose-derived stem cells and discuss why procedure standardization will elucidate the scientific bases for their broad use. Finally, the authors discuss challenges posed by U.S. Food and Drug Administration oversight of these cell-based therapies and examine the role of adipose-derived stem cell-based applications in the future of plastic surgery.

The Efficacy of Cell-Assisted Lipotransfer Versus Conventional Lipotransfer in Breast Augmentation: A Systematic Review and Meta-Analysis

BACKGROUND

Cell-assisted lipotransfer (CAL) is novel and controversial technique for breast augmentation.

OBJECTIVE

This review and meta-analysis aimed to assess the clinical efficacy of CAL as compared with conventional lipotransfer.

METHODS

PubMed databases were searched with no restrictions for randomized controlled trials (RCTs) and observational studies with control groups. Keywords included "fat graft," "lipotransfer," "lipofilling," "autologous fat," "fat transplantation," "stromal vascular fraction (SVF)," "stem cell," "adipose tissue-derived stromal cell (ADSC)," "adipose tissue-derived stromal cell (ASC)," "called adipose derived progenitor cells (ADRC)," "cell-assisted," "progenitor-enriched," "cell-enhanced" and "breast." Review Manager software (RevMan, version 5.3) was used to compute the pooled effect estimates for fat survival rate and complication rates. Outcomes were expressed as standard mean differences (SMDs) or odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses were performed based on different methods of cell-enhanced fat preparation.

RESULTS

Six studies were included (n_total = 353 adult patients). The fat survival rate was significantly higher in the CAL group than in the control group (SMD = 1.79, 95% CI = 0.28, 3.31; P = 0.02). There were no significant differences in complication rates between the CAL group and the control group (OR = 1.34, 95% CI = 0.65, 2.73; P = 0.43). Subgroup analyses found no significant differences between the SVF and control groups in fat survival rate (SMD = 1.52, 95% CI = -0.21, 3.24; P = 0.08) among both manual and automatic subgroups (P = 0.28 and P = 0.10, respectively). The data analysis showed a significant heterogeneity between manual and automatic subgroups (I² = 57.0%, P = 0.15).

CONCLUSION

This study suggests that cell-assisted lipotransfer is superior to conventional lipotransfer for improved fat survival rate in breast augmentation. However, analyses comparing the SVF-enhanced fat graft with the conventional fat graft noted no differences in fat survival rate. It is necessary to determine which protocol is most beneficial for patients, establish standardized methods of SVF isolation or adipose tissue-derived stromal cells (ADSCs) culture, and a constant percentage of injected cells in the graft. The long-term efficacy and safety of CAL should also be evaluated in further studies, and additional RCTs with larger sample sizes and better comparability are needed.

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.

Autologous Fat Transplantation for Aesthetic Breast Augmentation: A Systematic Review and Meta-Analysis

BACKGROUND

Autologous fat transplantation has already become a part of clinical practice for aesthetic breast augmentation even though evidence regarding its efficacy is still lacking.

OBJECTIVES

The authors sought to determine the current worldwide status and efficacy, techniques, and oncologic safety on this subject.

METHODS

PubMed, EMBASE, and Cochrane Library databases were searched to identify all relevant studies.

RESULTS

Eighty-four articles published between 1987 and April 2020, consisting of 6468 patients, were included, and 64 studies consisting of 5162 unique patients were included in the meta-analysis. Most studies had a low level of evidence (levels 2b-5); In this meta-analysis, there were 17 prospective cohort studies, 4 retrospective cohort studies, 6 case-control studies, and 38 case series. The publications were from 21 countries. Indications for autologous fat transplantation were aesthetic augmentation (93.2%) and congenital malformation (6.8%). Among the 5162 patients, 2 cases (0.04%) of cancer were reported. The meta-analysis revealed very high overall patient and surgeon satisfaction rates of 93% and 87%, respectively. Overall, only 1.56 sessions were needed to achieve the desired result. Long-term survival was calculated to be approximately 60% to 70% at 1-year follow-up. Only 8% of procedures resulted in clinical complications, and 5% of patients required biopsy because of abnormal clinical or radiological findings.

CONCLUSIONS

Autologous fat transplantation seems to be a major tool in aesthetic breast augmentation. Preoperative patient selection is essential but under-reported. Future research should focus on evaluating the technical and patient factors influencing the rate of fat survival and its oncological safety.

LEVEL OF EVIDENCE: 4

Large-Volume Autologous Fat Grafting to the Breast

Autologous fat grafting in the setting of breast augmentation and reconstruction has become globally accepted and routinely performed. There is general consensus that small-volume grafting is reproducible and predictable; however, large-volume fat grafting (>100 mL) is less predictable and is not as commonly performed. The aim of this article was to review outcomes following large-volume and megavolume fat grafting in the setting of breast augmentation and reconstruction. Level of Evidence: 4.

Overcoming functional challenges in autologous and engineered fat grafting trends

Autologous fat grafting offers significant promise for the repair of soft tissue deformities; however, high resorption rates indicate that engineered solutions are required to improve adipose tissue (AT) survival. Advances in material development and biofabrication have laid the foundation for the generation of functional AT constructs; however, a balance needs to be struck between clinically feasible delivery and improved structural integrity of the grafts. A new approach combining the objectives from both the clinical and research communities will assist in developing morphologically and genetically mature AT constructs, with controlled spatial arrangement and increased potential for neovascularization. In a rapidly progressing field, this review addresses research in both the preclinical and bioengineering domains and assesses their ability to resolve functional challenges.

Nontuberculous Mycobacteria Infection After Autologous Fat Grafting for Cosmetic Breast Augmentation

BACKGROUND

Autologous fat grafting has been widely applied in cosmetic breast augmentation in recent years. However, nontuberculous mycobacteria infection, as one of the multiple complications described in the literature, has been less well discussed.

OBJECTIVE

The aims of the study were to report 5 cases of nontuberculous mycobacteria infection after autologous fat injection for the cosmetic breast augmentation and to explore its causes.

METHODS

In this noncomparative, retrospective, and interventional case series, we identified 5 patients with nontuberculous mycobacteria infection. All patients had a history of previous autologous fat injection into the breast for cosmetic purpose, performed in different plastic facilities.

RESULTS

Five patients developed nontuberculous mycobacteria infection after autologous fat injection for cosmetic breast augmentation and came to our group for treatment. Grafted fat removal through multiple debridement and long-term intravenous and oral antibiotic therapy were required in our cases.

CONCLUSIONS

The number of nontuberculous mycobacteria infection after autologous fat injection into the breast is increasing. Surgeons should be aware of the complication, which rarely manifests during the procedure itself. Strict aseptic principles should be obeyed throughout the surgery.

Comparison of the Efficacy and Safety of Cell-Assisted Lipotransfer and Platelet-Rich Plasma Assisted Lipotransfer: What Should We Expect from a Systematic Review with Meta-Analysis?

Due to the high absorption rate of traditional autologous fat grafting, cell-assisted lipotransfer (CAL) and platelet-rich plasma (PRP)-assisted lipotransfer were developed. The purpose of this article was to evaluate the efficacy and safety of CAL and PRP in promoting the survival of autologous fat grafting through systematic review and meta-analysis. We searched Pubmed, Cochrane Library, Web of Science, and EMBASE for clinical studies on CAL and PRP-assisted lipotransfer published from January 2010 to January 2020. Then a meta-analysis was performed to assess the efficacy of CAL and PRP-assisted lipotransfer through data analysis of fat survival rate. We also assessed the incidence of complications and multiple operations to analyze their safety. A total of 36 studies (1697 patients) were included in this review. Regardless of the recipient area, CAL and PRP-assisted lipotransfer significantly improved the fat survival rate (CAL vs non-CAL: 71% vs 48%, P < 0.0001; PRP vs non-PRP: 70% vs 40%, P < 0.0001; CAL vs PRP: 71% vs 70%, P = 0.7175). However, in large-volume fat grafting, such as breast reconstruction, both increased the incidence of complications and did not decrease the frequency of multiple operations after lipotransfer. Further prospective studies are needed to evaluate the clinical benefits of CAL and PRP-assisted lipotransfer.

Anatomic Characteristics and Treatment of the Midcheek Groove by Deep Filling

BACKGROUND

Because the anatomic mechanisms underlying the formation of the midcheek groove are unclear, treatments to date have resulted in unsatisfactory outcomes.

OBJECTIVE

This study investigated the anatomical foundation of the midcheek groove and evaluated appropriate treatment methods.

MATERIALS AND METHODS

Six cadaver hemifacial specimens were subjected to gross anatomic dissection and 6 to P45 sheet plastination. Based on the anatomic results, the area under the orbicularis oculi muscle (OOM) was selected for deep filling. Patients were evaluated by measuring 3D depth, regrading, and self-assessment.

RESULTS

The medial band was observed to be an important structure of the OOM, with the facial projection overlapping the midcheek groove trace. Two of the 6 P45 specimens were found to have compact fibroelastic bundles (CFBs) between the medial band and the dermis. Deep filling of the area under the OOM significantly reduced the depth of each section in all 34 patients (p < .001). Grades 3 and 4 midcheek grooves were downgraded distinctively. Most subjects expressed satisfaction with outcomes.

CONCLUSION

Formation of the midcheek groove is associated with the passage of CFBs. Deep filling of the area under the OOM effectively improves the midcheek grooves.

Adipose-derived stem cell enrichment is counter-productive for the majority of women seeking primary aesthetic breast augmentation by autologous fat transfer: A systematic review

BACKGROUND

Autologous lipotransfer (AL) is a popular method despite unpredictable retention rates. Higher retention rates have been reported when co-administering adipose-derived stem cells (ASCs), a process called cell-assisted lipotransfer (CAL). Our hypothesis is that CAL might indeed limit volume gain in most women seeking aesthetic breast augmentation because it doubles the amount of fat required without consistently improving the outcome.

METHODS

Electronic databases were searched for articles published between January 2008 and October 2019 in English and German. All original articles evaluating fat viability following autologous breast augmentation in vivo were included. Based on the reported retention rates, potential volume gains were estimated for CAL and AL.

RESULTS

A total of 23 studies were selected. The AL retention rate varied from 39% to 76%, whereas CAL increased this rate at best by 24%. The body mass index (BMI) ranged from 18.8 to 23.4 (20.4±1.6) in the study population, whereas the BMI of women in the same age group is 28.7 (±8.4). We calculated that, starting from 200 ml of harvested fat and after two sessions of AL of 100 ml each, the volume retained would be at most 152 ml. In contrast, after one session of CAL of 100 ml, while the remaining 100 ml are used to isolate ASCs, a maximum of 95 ml of fat would remain.

CONCLUSION

The volume gain after two sessions of AL is far superior to that after one session of CAL for the same volume of harvested fat. This is an important practical consideration for women with low BMI, as the extra fat required to isolate ASCs is not counterbalanced by an increase in the retention rate. Therefore, two sessions of AL may be preferable to maximize the volume gain.

Complications after Breast Augmentation with Fat Grafting: A Systematic Review

BACKGROUND

Breast augmentation with fat grafting is used as an alternative to breast implants. However, a systematic evaluation of the complication rates after fat grafting using only studies with consecutive patients has not previously been performed. In this study, the authors compiled studies reporting complication rates and radiologic changes in consecutive patients undergoing cosmetic breast augmentation with fat grafting.

METHODS

Studies reporting on consecutive patients undergoing breast augmentation with fat grafting were included. Complication rates, radiologic changes, Breast Imaging Reporting and Data System assessments, and the number of patients undergoing revision surgery were extracted. Mean complication rates and radiologic changes were calculated with meta-analytical methods.

RESULTS

Twenty-two studies with 2073 patients were included. The rates of major complications were low (hematoma, 0.5 percent; infection, 0.6 percent; and seroma, 0.1 percent). None of these patients needed revision surgery. The most frequent minor complication was palpable cysts in 2.0 percent of the patients; 67 percent of these were treated with aspiration. The radiologic changes in the patients after fat grafting were as follows: oil cysts, 6.5 percent; calcifications, 4.5 percent; and fat necrosis, 1.2 percent. The risk of being referred for additional radiologic imaging (e.g., to exclude malignant changes) was 16.4 percent, and the risk of being referred for biopsy was 3.2 percent.

CONCLUSIONS

The complication rates after breast augmentation with fat grafting are low and support fat grafting as an alternative to breast augmentation with implants. The rates of radiologic changes are high after fat grafting, but the changes do not seem to have any therapeutic consequences for the patients.

Autologous fat graft assisted by stromal vascular fraction improves facial skin quality: A randomized controlled trial

BACKGROUND

Cell-assisted lipotransfer (CAL) promotes the survival of fat grafts with high vascular density and improves skin quality by increasing collagen content. However, no study has quantified the changes on the skin surface, and rigorous methodological evaluations are still lacking.

DESIGN

Fifty patients were recruited and randomly divided into two groups: an experimental group (n = 25) that underwent a stromal vascular fraction (SVF)-assisted fat graft and a control group (n = 25) that underwent fat graft only.

METHODS

The SVF cells were counted, tested in terms of viability, and characterized. The volumes of whole faces were determined by using a 3D scanner and Geomagic software preoperation, immediately after surgery, and 6 months postoperation. Facial skin qualities, including spots, wrinkles, texture, pores, UV spots, brown spots, red areas, and porphyrins, were detected by a VISIA skin detector preoperation and 6 months postoperation. A visual analog scale was used for clinical evaluation.

RESULTS

The cell pellet contained 1-3 × 10⁷/mL of fresh SVF cells. The cell viability exceeded 98%. The immunophenotyping characteristics and stemness were consistent with the features of adipose- derived stem cells (ADSCs). The survival rate of SVF-enriched fat grafts was significantly higher than that of control grafts: 77.6%±11.6% versus 56.2%±9.5% (p<0.001). The VISIA values of wrinkles (19.3 ± 6.6 versus 10.9 ± 5.5, p<0.001) and texture (15.8 ± 7.0 versus 10.3 ± 5.0, p<0.01) were significantly higher in SVF-enriched group than in control group at 6 months postoperation. During long-term follow-up, the majority of patients in both groups were satisfied with the final facial esthetic results.

CONCLUSIONS

Our results demonstrated the positive outcomes of autologous SVF-assisted fat graft in improving facial skin quality and its promising application potential in clinical settings. This study is registered at www. ClinicalTrials.gov, number NCT02923219.

Methods used for evaluation of volume retention rate in autologous fat grafting for breast augmentation: a systematic review

BACKGROUND

Autologous fat grafting has gained popularity in breast augmentation. Various methods can be used to estimate the volume retention rate. This systematic review aimed to establish whether the type of method used for measuring breast volume is a factor that influences the reported volume retention rate.

METHODS

Studies were identified using the electronic databases PubMed, Embase, Cochrane Central Register of Controlled Trials, and Web of Science from inception of the database up to February 2019. Articles describing autologous fat grafting for breast augmentation were selected based on pre-determined inclusion and exclusion criteria. The characteristics of the included studies were summarized, and the reported volume retention rate from the studies was compared. A quality assessment of all included articles was performed using the methodological index for non-randomized studies criteria.

RESULTS

A total of 618 articles were identified, of which 12 studies, with a total of 1337 cases, were eligible. The retention rate of injected adipose tissue varied when the method of fat grafting and volume analysis used were both the same, as well as when the method of fat grafting was the same but the method of volumetric evaluation used was different.

CONCLUSIONS

Currently, the tools available for estimating the volume retention rate come with limitations. In order to objectively evaluate the percentage of graft retention, a standard protocol that applies to the different methods should be established in the future.

The Effect of Respiration on Breast Measurement Using Three-dimensional Breast Imaging

BACKGROUND

Three-dimensional (3D) imaging offers new opportunities to enable objective and quantitative analysis of the breast. Unlike scanning of rigid objects, respiration may be one of the factors that can influence the measurement of breast when using 3D imaging. In this study, we aimed to investigate how the different respiratory phases affect 3D morphologic and volumetric evaluations of the breast.

METHODS

We performed preoperative 3D breast imaging at the end of expiration (EE) and the end of inspiration (EI). We repeated scans on each respiratory phase, taking four scans in total (EE1, EE2 and EI1, EI2). Using Geomagic Studio 12 software, measurements from the different respiratory phases (EE1 and EI1) were compared for differences in the linear distances of breast. Breast volumetric change error (BVCE) was measured between EE1 and EE2 (R1) and between EI1 and EI2 (R2). A multilevel model was used to analyze the difference of linear-distances parameters between EE1 and EI1 and a paired sample t-test was used to analyze the difference between R1 and R2.

RESULTS

Our study included 13 Chinese women (26 breasts) with a mean age of 32.6 ± 6.3 years. Compared with EI, EE showed a longer sternal notch to the level of the inframammary fold and shorter nipple to midline (p < 0.05). During EI, breast projection increased by 0.23 cm (95% CI - 0.39, - 0.08) and breast base width increased by 0.27 cm (95% CI - 0.46, - 0.09). The position of the nipple moved by 0.18 cm (95% CI - 0.34, - 0.03) laterally, 0.41 cm (95% CI 0.18, 0.64) cranially, and 0.71 cm (95% CI - 0.92, - 0.51) anteriorly. Although there was no significant difference in BVCE between EE and EI, the result seen with EE appeared to be more consistent.

CONCLUSIONS

The results of this study demonstrate that there was no difference in breast volume results when patients are in the expiratory or inspiratory state during 3D breast imaging. This study, however, holds potential benefits to both surgical practice as well as the 3D imaging industry.

LEVEL OF EVIDENCE IV

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