Three-dimensional Volumetric Analysis of 3 Fat-Processing Techniques for Facial Fat Grafting: A Randomized Clinical Trial

Autologous fat grafting auxiliary methods in craniofacial deformities: A systematic review and network meta-analysis

BACKGROUND

To increase autologous fat grafting (AFG) volume retention, current advancements focus on adding an auxiliary method to the process. This review aimed to address which auxiliary methods prove to be the best in terms of volume retention outcome.

METHODS

A comprehensive literature search was performed in five medical databases, including PubMed, Proquest, Scopus, CENTRAL, and ScienceDirect, until March 2024, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines.

RESULTS

Twenty-six studies were included in this review, and seven studies were included in the network meta-analysis. Reported auxiliary methods include stromal vascular fractions (SVFs) [12.20, 95% confidence intervals (CI) 0.04 to 24.35], adipose tissue-derived stem cells (ADSCs) (24.20, 95% CI 4.14 to 44.26), and platelet-rich plasma (PRP) [24.10, 95% CI -2.68 to 50.88]. When compared with the standard AFG approach, SVFs (p = 0.049) and ADSCs (p = 0.018) were more successful in retaining volume. However, PRP (p = 0.077) was not as effective. The comparison between auxiliary approaches, ADSCs vs PRP (p = 0.994), ADSCs vs SVFs (p = 0.271), and PRP vs SVF (p = 0.383), did not show any significant differences. Subgroup analysis revealed that the use of volumetric measuring methods has a substantial impact on the reported volume retention (p < 0.0001).

CONCLUSION

Enhanced volume retention can be attained with the utilization of SVF and ADSCs auxiliary methods in comparison to AFG, with or without PRP. Given the insignificant differences between SVF and ADSC, along with the greater complexity of the ADSC process, we recommend for the preferable use of SVF.

Enhanced Transconjunctival Lower Blepharoplasty: A Novel Method for Intraorbital Fat Transposition and Stabilization

BACKGROUND

The evolution of lower blepharoplasty has shifted from simply removing of orbital septum fat to smoothing of the lid-cheek junction through fat repositioning. This paper adopts a novel technique to transpose and stabilize intraorbital fat during transconjunctival lower blepharoplasty. The tear trough and nasal alar base were filled to correct the pouch while ensuring the blood supply of the fat flap.

METHODS

Between September 2019 and June 2022, 104 patients aged between 22 and 49 who underwent bilateral fat flap transposition-nasal alar base filling lower blepharoplasty were selected. The surgical results were assessed by non-operative plastic surgeons according to the Hirmand grading system. Moreover, a self-satisfaction survey was conducted and patients were followed up for at least 6 months to evaluate any complications and surgical outcomes. A high-frequency ultrasound imaging system was used to assess the degree of filling of the tear trough and nasal alar base.

RESULTS

All 104 patients were followed up for at least 6 months. The postoperative Hirmand grade was 0 for 96 out of 104 (92.3%) patients. In terms of self-satisfaction assessment, there were 92 out of 104 (88.5%) patients reported satisfaction. Dermatologic ultrasound showed no obvious gaps 6 months after surgery.

CONCLUSION

Transconjunctival fat flap transposition combined with nasal alar base filling during lower blepharoplasty has been shown to have a positive postoperative effect and high patient satisfaction. This procedure can preserve the blood supply of the fat flap, reduce the rates of fat absorption and denaturation, and improve facial contour, resulting in a satisfactory repairing effect.

LEVEL OF EVIDENCE II

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 .

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.

Poloxamer 188 washing of lipoaspirate improves fat graft survival: A comparative study in nude mice

BACKGROUND

Autologous fat transplantation is limited by the uncertainty of graft retention, impeding its application. Among the current strategies for processing lipoaspirates, high-density fat (HDF) is recommended owing to the enrichment of stem cells and washing before cotton concentration for simplicity of operation. Poloxamer 188 (P188) washing has been shown to repair the membranes of damaged cells. This study aimed to investigate the effect of P188-washing on fat graft survival and identify the best technique for processing lipoaspirates.

METHODS

Lipoaspirates were prepared using centrifugation to obtain HDF, which was then washed with saline or P188 followed by cotton concentration. Tissue integrity, adipocytic activity, and viability of stromal vascular fraction (SVF) in the samples from the 3 groups were assessed. Samples were sequenced in vitro using high-throughput RNA-seq, and differentially expressed genes were validated using qPCR and western blotting (WB). After transplantation under the dorsum of nude mice for 8 weeks, the grafts were extracted and examined for residual volume, histologic characteristics, and vascularization.

RESULTS

The HDF and P188 groups showed a higher survival rate of SVF, more Ki67-positive cells, intact tissue structure, and lesser fibrosis than the saline group. There were no significant differences in the density of SVF and residual volume of grafts. HDF showed significantly improved vascularization during 8 weeks. Through RNA-seq and bioinformatic analysis, notable changes in several related genes after transplantation were observed.

CONCLUSIONS

P188 treatment can prevent cells from apoptosis and preserve tissue viability, thereby improving graft quality. HDF contains large amounts of SVF and can be regarded as an excellent grafting material.

Fat or fillers: The dilemma in eyelid surgery

The aging of the periocular region has always aroused great interest. A fresh, young, and attractive sight determined an ever-greater attention to surgical and non-surgical techniques to obtain this result. In particular, the change in the concept of a young look, considered then "full", led to the increasing use of surgical (fat grafting) or medical (hyaluronic acid) filling techniques. Eyelid rejuvenation became increasingly popular in the field of cosmetic treatments, with a focus on achieving a youthful and refreshed appearance. Among the various techniques available, the choice between using fat grafting or fillers presented a clinical dilemma. In particular, what surgery considered of fundamental importance was a long-lasting result over time. On the other hand, aesthetic medicine considered it fundamental not to have to resort to invasive treatments. But what was the reality? Was there one path better than the other, and above all, was there a better path for patients? The minireview aims to explore the physiopathology, diagnosis, treatment options, prognosis, and future studies regarding this dilemma. We analyzed the literature produced in the last 20 years comparing the two techniques. Current literature reveals advancements in biomaterials, stem cell research and tissue engineering held promise for further enhancing the field of eyelid rejuvenation. The choice between fat grafting and fillers in eyelid cosmetic treatments presented a clinical dilemma. Understanding physiopathology, accurately diagnosing eyelid aging, exploring treatment options, assessing prognosis, and conducting future studies were essential for providing optimal care to patients seeking eyelid rejuvenation.

Exploring Preclinical Experiments with Different Fat Types for Autologous Fat Grafting

BACKGROUND

Autologous fat transplantation has been a cornerstone of tissue regeneration for decades. However, there is no standardized selection system or criteria for fat graft selection, often relying heavily on the surgeon's experience.

OBJECTIVES

This study aimed to investigate various types of fat derivatives, both in vitro and in vivo at the same condition.

METHODS

We collected traditional fat granules of different sizes and SVF-gel, evaluating the viability of ADSCs isolated from them and their performance after grafting into mice.

RESULTS

Large fat granules exhibited more complete adipocyte structures, and the isolated ADSCs demonstrated superior differentiation, proliferation, and secretion capacities. They also showed excellent volume retention after 12 weeks. In contrast, ADSCs isolated from SVF-gel displayed lower vitality. However, grafts from SVF-gel exhibited the highest volume maintenance rate among the four groups after 12 weeks, closely resembling normal adipose tissue and displaying significant vascularization. Compared to large fat granule and SVF-gel group, medium and small fat granule grafts exhibited lower volume retention and less angiogenesis.

CONCLUSIONS

Through preclinical studies, the flexible clinical use of different fat grafts can be tailored to their unique characteristics.

LEVEL OF EVIDENCE I

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 fat grafting and cancer: a systematic review of the science behind enhancements and concerns

Background

Autologous fat transfer (AFT) is gaining popularity in breast surgery, offering a natural-looking and minimally invasive approach for augmentation, reconstruction, and contouring. However, concerns about its impact on breast cancer necessitate an understanding of the interplay between transplanted adipose-derived stem cells (ADSCs) and the breast tissue microenvironment. Renowned for regeneration, ADSCs raise questions about their role in cancer promotion. This systematic review delves into the complex relationship between AFT and breast cancer, exploring how ADSCs may influence development, growth, and metastasis.

Methods

A systematic search of electronic databases, including PubMed, Embase, and BVS was conducted to identify relevant studies. The search strategy employed a combination of keywords, including "breast augmentation", "fat grafting", "breast enhancement", "mammoplasty", "cancer", "neoplasm" and related terms. Two reviewers independently screened titles and abstracts. Full-text articles were then retrieved for further evaluation based on their potential contribution to the review objectives.

Results

Two hundred and forty records were identified. Among these, 104 duplicates were removed, resulting in 136 reports available for title and abstract screening. Subsequently, 54 papers were deemed potentially eligible for inclusion, and all reports were retrieved.

Conclusions

In vitro studies reveal ADSCs dual role in breast cancer, influencing proliferation, migration, and drug resistance through complex signaling pathways. Animal studies highlight distinct ADSC subpopulations impacting tumor growth via direct interactions and extracellular vesicle cargo. In vivo, ADSC-enriched fat grafting is generally safe, showing no increased cancer recurrence risk compared to other methods. Notably, cases of invasive breast carcinoma warrant special attention. ADSC-enriched fat grafts exhibit potential benefits in graft retention and survival rates. Despite promising evidence, further studies are needed to comprehensively understand the intricate relationship between ADSCs and breast cancer for optimized clinical applications and potential therapeutic innovations.

Stromal Vascular Fraction Gel (SVF-Gel) Combined with Nanofat for Tear Trough Deformity

BACKGROUND

Tear trough deformity makes patients appear tired. Patients with less severe tear trough deformity prefer a less invasive method to correct the deformity. The infraorbital area is a multilayered tissue, and the aging of various components leads to tear trough deformity. To this end, we utilized the different characteristics of different fat derivatives to correct tear trough deformity.

METHODS

Thirty-two patients with Barton Grade I/II tear trough deformity were enrolled in this study between September 2020 and March 2021. We injected Stromal Vascular Fraction Gel (SVF-Gel) into the suborbicularis oculi fat layer and Nanofat into the subcutaneous. After 12 months of follow-up, we evaluated the changes using standardized clinical photogrammetric techniques, volume, global aesthetic improvement scale, and patient self-evaluation.

RESULTS

There were no major complications in any of the 32 patients. The measured data points demonstrated improvements in all aesthetic parameters. The width of the tear trough and the distance from the pupil to the tear trough improved. The Global Aesthetic Improvement Scale (GAIS) showed a high score (2.45±0.64 points), with patient self-assessment showing satisfactory results.

CONCLUSION

SVF-Gel combined with Nanofat injection can effectively correct tear trough deformities.

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 .

Quantifying outcomes of autologous fat transplantation in different facial deformities: A systemic review and meta-analysis

BACKGROUND

Autologous fat transplantation has become a common treatment for facial deformities. However, facial deformities are the result of complex diseases with different causes, and there has been no review on the effectiveness of autologous fat transplantation for facial deformities of different aetiologies.

METHODS

A systematic literature search of the Web of Science, Embase, and Medline Ovid databases was performed up to December 2022. Two investigators independently performed screening and data extraction according to Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines, followed by a meta-analysis using random-effects model for surgeon and patient satisfaction, facial symmetry, and complication rates. Twelve-month postoperative fat graft retention was estimated by meta-regression.

RESULTS

Thirty-one studies met the criteria, including 13 case series studies, 14 cohort studies, and four randomized clinical trials, with a total of 1572 patients. Follow-up visits within 6-12 months were performed in most of the studies. The results of the meta-analysis showed high overall surgeon satisfaction of 97% (95% CI: 92%-100%) and patient satisfaction of 95% (95% CI: 89%-99%), with a low complication rate of 3.4% (95% CI: 1.9%-5.9%). At 12 months postoperatively, a lower retention rate of 43% (95% CI: 28%-58%) was estimated in cases of acquired atrophic deformities compared with 64% (95% CI: 57%-71%) in cases of mixed deformities. Overall, autologous fat transplantation improved facial symmetry by 13% (95% CI: 8.4%-18%).

CONCLUSION

Autologous fat transplantation is generally a safe and effective procedure that can compensate for facial volume deficits and improve facial symmetry but may be less effective in cases of acquired atrophic facial deformities.

Autologous Fat Grafting for Functional and Aesthetic Improvement in Patients with Head and Neck Cancer: A Systematic Review

INTRODUCTION

The efficacy and safety of autologous fat grafting for use in oncology patients are controversial. Patients with head and neck cancer have complex anatomy and require reconstructive repair of the head and neck after comprehensive treatment. The limited additional aesthetic and functional studies on the use of autologous fat fillers in patients with head and neck cancer are unclear. This study systematically evaluates the additional function of autologous fat fillers in the head and neck and systematically reviews issues related to autologous fat grafting after comprehensive head and neck cancer treatment, including current indications, techniques, potential complications, graft survival, and patient satisfaction.

METHODS

A systematic literature review was performed using PubMed, The Cochrane Library, EMBASE, and Web of Science (last accessed on January 9, 2023).

RESULTS

A total of 249 cases of autologous fat fillers in patients with head and neck cancer were reported in 10 clinical publications. Observations were based mainly on subjective physician and patient evaluation indicators, and all studies reported the beneficial effects of autologous fat fillers on aesthetics and function after treatment for head and neck cancer.

CONCLUSIONS

Autologous fat fillers are effective in improving the aesthetics and function of head and neck cancer, and due to the limitations of the original study, future studies with large samples are needed to support this. PROSPERO registration number is CRD42020222870.

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 .

Three-Dimensional Volumetric Analysis of the Effect of Interval Time in Autologous Fat Graft Breast Augmentation

BACKGROUND

Autologous adipose tissue has become increasingly popular in cosmetic and plastic reconstructive surgery, especially breast augmentation surgery. However, the volume retention rate after transplantation significantly varies and may be unsatisfactory. Many patients need two or more autologous fat graft breast augmentations to achieve the expected effect. There are currently no studies on optimal timing between fat injections.

METHODS

We identified target patients with secondary or multiple autologous fat transplantations by inclusion and exclusion criteria and used three-dimensional scanning technology to calculate the volume retention. Patients were divided into two groups according to the dates of the first and second operations (group A: interoperative time < 120 days, group B: interoperative time ≥ 120 days). We used SPSS 26 for statistical calculations.

RESULTS

We included 161 patients in this retrospective study, with an average volume retention rate of 36.56% in group A (n = 85) and 27.45% in group B (n = 76). The independent sample t test showed that the volume retention rate in group A was higher than that in group B (P < 0.001). And the paired t test showed there is a significant improvement of volume retention rate after the second fat graft session (P < 0.001). Multivariate regression analysis showed that the interval time was an independent factor affecting the postoperative volume retention rate.

CONCLUSION

The interval time between autologous fat transplantation for augmentation mammaplasty was an independent factor affecting the postoperative volume retention rate. The postoperative volume retention rate of the < 120 days group was higher than that of the ≥ 120 days group.

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 .

Strategies to Improve AFT Volume Retention After Fat Grafting

BACKGROUND

Autologous fat grafting has gained increasing popularity used in plastic surgery as a strategy to improve functional and aesthetic outcome. However, variable augmentation results have concerned surgeons in that volume loss of grafted fat reported fluctuates unsteadily.

AIM

An optimal technique that clinically maximizes the long-term survival rate of transplantation is in urgent need to be identified.

METHOD

The PubMed/MEDLINE database was queried to search for animal and human studies published through March of 2022 with search terms related to adipose grafting encompassing liposuction, adipose graft viability, processing technique, adipose-derived stem cell, SVF and others.

RESULTS

45 in vivo studies met inclusion criteria. The principal of ideal processing technique is effective purification of fat and protection of tissue viability, such as gauze rolling and washing-filtration devices. Cell-assisted lipotransfer including SVF, SVF-gel and ADSCs significantly promotes graft retention via differentiation potential and paracrine manner. ADSCs induce polarization of macrophages to regulate inflammatory response, mediate extracellular matrix remodeling and promote endothelial cell migration and sprouting, and differentiate into adipocytes to replace necrotic cells, providing powerful evidence for the benefits and efficacy of cell-assisted lipotransfer.

CONCLUSION

Based on the current evidence, the best strategy can not be decided. Cell-assisted lipotransfer has great potential for use in regenerative medicine. But so far mechanically prepared SVF-gel is conducive to clinical promotion. PRP as endogenous growth factor sustained-release material shows great feasibility.

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.

Correction of breast asymmetry by autologous fat grafting with the aid of 3D laser-scanning technology

BACKGROUND

Currently, the lack of clinically accurate measurement and evaluation methods for breast asymmetry has considerably limited the use of autologous fat grafting in the correction of breast asymmetry.

OBJECTIVE

This study calculated the volume difference in the bilateral breasts by three-dimensional (3D) laser scanning technology, established a bridge between digitalization and surgery to guide the correction of breast asymmetry by autologous fat grafting, and evaluated the surgical effect.

METHODS

In the experimental group (3D group), the measurement range was defined by standardized methods, the algorithm to calculate the volume difference in the bilateral breasts was determined by the established software instructions, and the volume of intraoperative autologous fat grafting was guided by personalized data. In the control group, the volume of intraoperative autologous fat grafting was determined based on the surgeon's visual assessment and surgical experience.

RESULTS

The volume difference in the bilateral breasts was less at 12 months after surgery (P < 0.05), the satisfaction of patients was higher (P < 0.05), and the reoperation rate was lower (P < 0.05). The incidence of postoperative complications was low in both groups (P > 0.05).

CONCLUSIONS

3D laser scanning technology can be used as a bridge between digitalization and surgery to significantly improve the surgical effect of autologous fat grafting in the correction of breast asymmetry, with high patient satisfaction and high clinical application value.

Contouring and augmentation of the temple using stromal vascular fraction gel grafting

Background

Hollowing temples are common in aging Asians. Stromal vascular fraction (SVF) gel is a novel, mechanically processed adipose-derived product containing condensed adipose-derived stem cells and native extracellular matrix, allowing improved fat grafting. The present study evaluated the effectiveness of SVF-gel treatment on temple hollowing.

Methods

This prospective, single-center study included an SVF-gel grafting group (n = 34) and a Coleman's fat grafting group (n = 29). Temple contour was assessed using preoperative and postoperative photographs. Temple augmentation was quantified using three-dimensional (3D) technology and an MVS-600 3D scanner system. Patient satisfaction was assessed postoperatively.

Results

At 12 months follow-up, the minimal forehead width/forehead width ratio and the width of the temporal peak were increased in both groups (p < 0.05).; and the retention rate (41.2% ± 8.4%) of the SVF-gel group was significantly higher than that of Coleman's fat group (32.6% ± 8.8%; p < 0.05). Moreover, patients in the SVF-gel group reported higher satisfaction scores than those in Coleman's fat group.

Conclusions

SVF-gel is effective for temple contouring and augmentation., with increased efficacy compared with Coleman's fat.

Volumetric Effect and Patient Satisfaction after Facial Fat Grafting

BACKGROUND

Facial fat grafts decrease in volume after transplantation. This observation is based on overall facial three-dimensional analyses, because there is sparse information on volume changes in well-defined aesthetic areas. The authors aimed to assess the overall and, more specifically, the local volumetric effects of facial fat grafting and relate these effects to patient satisfaction up to 1 year after treatment.

METHODS

All consecutive adult female patients who were scheduled for facial fat grafting without additional surgical procedures were asked to participate. All patients underwent the same fat grafting method. An algorithm-based personalized aesthetic template was applied to define specific aesthetic areas on the preoperative three-dimensional image. Objective outcome parameters [i.e., three-dimensional volume differences, patient satisfaction (FACE-Q questionnaire)] were measured at baseline and at 6 weeks, 6 months, and 12 months after fat grafting.

RESULTS

Of 33 female patients who underwent a facial fat graft procedure, 23 patients had complete three-dimensional data and were eligible for analysis. The highest volume gain was observed 6 weeks after grafting and was followed by a gradual loss thereafter. Overall and in the zygomatic area, a substantial gain in volume was still present 1 year after grafting, whereas this effect was lost in the lip area. FACE-Q scales Satisfaction with Facial Appearance Overall and Satisfaction with Cheeks improved too, whereas scores for Lines: Lips returned to baseline levels. The improvement in FACE-Q scales was in agreement with the objective change in volume.

CONCLUSION

Gain in overall and local volumetric effects is accompanied by comparable changes in patient satisfaction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

The Importance of Protecting the Structure and Viability of Adipose Tissue for Fat Grafting

BACKGROUND

Fat grafting is widely used for soft-tissue augmentation; however, the related clinical outcome remains variable and technique-dependent. The mechanisms underlying fat graft survival are not fully understood, particularly regarding the contributions of different cell types, such as functional adipocytes. This study evaluated the importance of adipose tissue structure and viability in fat grafting and, to some extent, revealed the effect of adipocytes in fat grafting.

METHODS

Human lipoaspirate was harvested using suction-assisted liposuction and processed using three separate methods: cotton-pad filtration, soft centrifugation (400 g for 1 minute), and Coleman centrifugation (1200 g for 3 minutes). Then all samples were subjected to second cotton-pad concentration. Adipose tissue structure and viability, the numbers of adipose-derived stem cells, and their proliferation and multilineage differentiation abilities were compared in vitro. The volume retention rate and fat graft quality were evaluated in vivo.

RESULTS

Cell structure destruction and viability decline were more evident in the Coleman centrifugation group compared to the cotton-pad filtration group and the soft centrifugation group. However, no intergroup differences were observed in the numbers, proliferation, or multilineage differentiation abilities of adipose-derived stem cells. After transplantation, the volume retention rates were similar in the three groups. However, greater structural and functional damage was associated with poorer graft quality, including decreased levels of graft viability, vessel density, and vascular endothelial growth factor secretion and increased levels of vacuoles, necrotic areas, fibrosis, and inflammation.

CONCLUSIONS

Protecting adipose tissue structure and viability is crucial for improving fat grafting outcomes.

CLINICAL RELEVANCE STATEMENT

The protection of the structure and viability of adipose tissue should be ensured throughout the whole process of fat grafting to reduce complications and improve graft quality.

The Safety of Fat Grafting: An Institutional Retrospective Review

BACKGROUND

Autologous fat grafting is a popular technique for volume replacement in the breast and face. The efficacy, safety, and complication rate of this technique at the division of plastic surgery at the University of Alabama at Birmingham will be described in this review.

METHODS

An institutional review board-approved retrospective review of patients undergoing fat grafting procedures from January 2015 to July 2018 was performed. Records were reviewed for fat graft recipient site, donor site, amount grafted, and complications. Continuous variables were compared using either a t test or one-way analysis of variance test. Categorical data were compared using χ2 test. A P value of 0.05 or less was considered statistically significant for all comparisons.

RESULTS

A total of 396 patients who underwent fat grafting procedures of the face and body from January 2015 through July 2018 met inclusion criteria. Average amount of fat grafted for all grafts was 124.4 +/- 6.74 grams. Two hundred fifty of the grafts (62.7%) involved the bilateral breasts with an average of 140.6 +/- 93.97 g used, 70 per side. Of the 396 patients, 110 (27.8%) experienced complications. Forty three of the complications (10.9%) were considered to be major, which included hematomas/seromas, fat necrosis, dermatitis/cellulitis, and infection. No statistical differences were seen among recipient site complication rate. Types of minor complications were statistically significant per recipient sites with bilateral breasts more likely to experience asymmetry than the other recipient sites (20% for bilateral breasts vs 16% overall, P < 0.05). Fifty nine of the 110 patients (53.6%) had the complications reported to be resolved.

CONCLUSIONS

Fat grafting is a reliable method for volumization of the breasts and face. Minor complications were not infrequent in this case series; however, no life-threatening complications were observed. Continued work needs to be done to use fat grafting beyond traditional measures.

Long-Term Effects of Platelet-Rich Fibrin on Fat Graft Survival and Their Optimal Mixing Ratio

BACKGROUND

Platelet-rich fibrin (PRF) can promote fat graft survival, but the reported mixing ratio of PRF to fat ranges from 1:25 to 1:2, lacking a clear standard for clinical application.

OBJECTIVES

The authors sought to explore the long-term effects of PRF on grafted fat and their optimal mixing ratio.

METHODS

Nude mice were randomly divided into a control group (receiving subcutaneous injection of fat granules) and 4 PRF groups (receiving subcutaneous injection of PRF and fat granules at volume ratios of 1:5, 1:10, 1:15, and 1:20, respectively). The graft samples (n = 12) were obtained in weeks 4, 8, and 12 to (1) calculate retention rates; (2) evaluate gene and protein expression of vascular endothelial growth factor A (VEGF-A), peroxisome proliferator-activated receptor-γ (PPAR-γ), type I collagen A1 (COL1-A1), and B-cell lymphoma-2 associated X protein (BAX); (3) perform hematoxylin and eosin, Masson's trichrome, α-smooth muscle action, and periplipin-1 stainings; and (4) count the microvessels and viable adipocytes.

RESULTS

Compared with the control group, PRF groups had higher retention rates, a higher gene/protein expression of VEGF-A, a lower gene/protein expression of COL1-A1 and BAX, less fibrosis, and more microvessels and viable adipocytes. Group 1:10 was superior to other groups in terms of retention rates and other evaluation indexes. The expression of PPAR-γ did not significantly differ among groups.

CONCLUSIONS

PRF may not play a long-term effect on adipogenesis, but it can still promote fat graft survival through facilitating vascularization, regulating collagen production, and inhibiting apoptosis. PRF can achieve the best promoting effect when the mixing ratio of PRF to fat is 1:10, which is recommended as the optimal ratio for clinical application.

Assessment of the Causes of Differences in Centrifugation Protocols as a Fat-Processing Technique: A Systematic Literature Review

BACKGROUND

Centrifugation has been widely used for fat graft processing. However, numerous different centrifugation protocols have been proposed in different studies. Investigation of these major differences is needed to clarify ambiguities and to achieve standardization. This review aimed to assess the causes of differences in centrifugation protocols as a fat-processing technique.

METHODS

Full-text and English-language articles between 1990 and 2020 were included in this study. Articles that assess the effect of centrifugation on fat graft survival with the following research purposes were selected: determination of the effect of centrifugation force/speed, determination of the effect of centrifugation time/duration, and comparison with other fat-processing techniques.

RESULTS

Fifty-four full-text, English-language articles were included. The number of articles that assessed centrifugation force/speed was 17 and centrifugation duration/time was 4, and the number of articles that compared centrifugation with other fat-processing techniques was 29 and centrifugation with noncentrifugation techniques was 4. Based on the study design, 25 experiments were performed in vivo, and 41 were performed in vitro.

CONCLUSION

Misuse of force (g) and speed (rpm) for defining the centrifugation protocol, differences in selected techniques for the graft harvest and graft transfer steps and differences in the analysis methods for fat graft survival are the main causes of these substantial variations among studies.

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.

Application of a Proposed Multi-Positional Circumferential Arm Liposuction Method and Quantification of its Clinical Efficacy Evaluation

BACKGROUND

Upper arm liposuction mainly focuses on the posterolateral region, which may lead to a lack of harmony between the aspirated and unaspirated areas. In addition, the treatment effect of arm liposuction is often evaluated only by preoperative and postoperative photograph comparison and simple measurement; quantitative research on this topic is still lacking.

METHODS

The multi-positional circumferential arm liposuction (MCAL) technique was proposed and applied to a total of 34 females in our hospital from 2017 to 2019. Three-dimensional data of 12 patients before the operation and after 2-3 months were collected and processed by 3D imaging, and the volume reduction rate was evaluated quantitatively.

RESULTS

The MCAL method was successfully applied in the clinic, and its surgical effect was quantitatively studied. The mean follow-up time of 12 patients was (75.2 ±13.1) days, and the postoperative volume was significantly reduced. The postoperative volume of patients with type I, type II and type III decreased by (10.79 ±2.55)%, (17.25 ±3.02)% and (22.76 ±3.51)%, respectively.

CONCLUSION

Our new MCAL technique was successful, maximizing the esthetic results in upper limb contour refinements in the superficial fascial layer. The clinical efficacy of this proposed MCAL method was evaluated by CT and 3D digital technology, which provided further accuracy in demonstrating its effect on the shape of the arm.

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 https://www.springer.com .

Volume Retention After Facial Fat Grafting and Relevant Factors: A Systematic Review and Meta-analysis

BACKGROUND

Autologous fat grafting is common in facial reconstructive and cosmetic surgeries; the most important drawbacks are the high absorption rate and unpredictable volume retention rate. Surgeons usually make clinical judgements based on their own experience. Therefore, this study aimed to systematically and quantitatively review the volume retention rate of facial autologous fat grafting and analyse the relevant influencing factors.

METHODS

A systematic literature review was performed using the Medline, EMBASE, Cochrane Library, and Web of Science databases in October 2019 for articles that reported objectively measured volume retention rates of facial fat grafting. Patient characteristics, fat graft volumetric data, and complications were collected. A meta-analysis using a random-effects model was conducted to pool the estimated fat retention rate. Relevant factors were analysed and reviewed on the basis of subgroups.

RESULTS

We included 27 studies involving 1011 patients with facial fat grafting. The volume retention rate varied from 26 to 83%, with a mean follow-up of 3-24 months. The overall pooled retention rate was 47% (95% CI 41-53%). The volume measurement method significantly influenced the reported retention rate. A trend towards better retention was found for secondary fat grafting procedures and patients with congenital deformities. Only 2.8% of all patients had complications.

CONCLUSION

The exact percentage of facial fat grafts retained is currently unpredictable; the reported rate varies with different estimation methods. This review analysed studies that provided objectively measured volume retention rates, the pooled average percentage of facial fat graft retention (47%, 95% CI 41-53%), and relevant factors.

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 .

Fat Processing Techniques: A Narrative Review

OBJECTIVE

This study reviewed the literature regarding different fat processing techniques, in order to update the information for healthcare personnel and provide the latest evidence in selecting purification methods.

METHODS

PubMed (MEDLINE), EMBASE, the Cochrane Library, and the Cochrane Central Register of Controlled Trials were comprehensively searched to identify studies that compared different fat purification methods for animal and human studies published through July 2020. Papers were screened using inclusion and exclusion criteria, and relative data were collected for review.

RESULTS

A total of 3292 studies were identified, of which 30 were included for review. The findings of existing clinical studies showed that the filtration and washing filtration methods performed better in the volume retention rate of adipose tissue. In terms of postoperative complications (fat necrosis, nodules, cysts, etc.), the incidence of complications of centrifugation is generally higher than that of other purification methods, while Telfa gauze and washing filtration system show better safety. More comparative studies are needed to draw conclusions about clinical efficacy and satisfaction. The existing basic science studies generally believe that centrifugation has no advantage in the integrity and metabolic activity of adipose tissue. However, there is no definite conclusion about the volume retention rate of grafts in animal experiments.

CONCLUSION

In recent years, studies on the cost-effectiveness of various purification methods have emerged, and the efficiency advantages of commercial systems have also been gradually reflected. In the future, the purification efficiency will be improved based on ensuring clinical efficacy, which will be translated into cost savings.

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 .

Transconjunctival lower eyelid blepharoplasty with fat transposition above the orbicularis muscle for improvement of the tear trough deformity

BACKGROUND

The tear trough is the hollow concavity of the medial lower eyelid. Surgery can address tear trough deformities and reverse visible signs of periorbital aging. The previous methods of transconjunctival blepharoplasty with fat transposition were first described with subperiosteal placement of fat (Plast Reconstr Surg, 125, 2010,699, Aesthetic Surg J, 32, 2012, 426). This was followed by techniques with submuscular transposition of fat, which overcame certain difficulties associated with the subperiosteal methods (Clin Plast Surg, 20, 1993, 393, Arch Facial Plast Surg, 2, 2000, 16).

OBJECTIVES

We present a detailed description, evaluate the efficacy, safety, and advantages of transconjunctival blepharoplasty with fat pedicle transposition above the orbicularis muscle for lower eyelid rejuvenation and improvement of the tear trough deformity.

METHODS

Forty-one patients underwent lower eyelid blepharoplasty with fat transposition above the orbicularis muscle. Clinical and photographic documentation along with patient satisfaction ratings were evaluated for a minimum of 44 months postoperatively.

RESULTS

Significant improvements of lower eyelid aesthetics and correction of tear trough abnormalities were observed in most patients. At 44 months postoperatively, surgical correction was maintained in all patients with a high satisfaction and long-term survival. No contour irregularities or significant long-term complications were detected in any of the patients.

CONCLUSION

Transconjunctival blepharoplasty with the fat pedicle transposition placed above the orbicularis muscle is a safe and effective technique for lower eyelid rejuvenation. Compared to previously described techniques of repositioning fat into the subperiosteal or submuscular plane, this technique of transposing fat above the orbicularis muscle is an alternative technique resulting in long-term improvement of tear trough abnormalities with no major complications.

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.

Correction of the Tear Trough Deformity and Concomitant Infraorbital Hollows With Extracellular Matrix/Stromal Vascular Fraction Gel

BACKGROUND

The tear trough deformity is a sign of eye aging. Filling is an ideal choice for the tear trough accompanied by infraorbital hollows.

OBJECTIVE

To evaluate the efficacy and safety of stromal vascular fraction gel (SVF-gel) as a filler for the tear trough deformity which is combined with infraorbital hollows.

MATERIALS AND METHODS

From July 2017 to June 2018, 33 patients underwent autologous fat aspiration and were followed up successfully. Stromal vascular fraction gel was used to correct patients with bilateral Barton I/II; tear trough deformity and infraorbital hollows. Improvement was evaluated by measuring skin-periosteal depth, 3D volume, global aesthetic improvement scale (GAIS), and patient self-assessment.

RESULTS

Skin-periosteal depth improved significantly (p < .001). The volumetric increment of the tear trough and infraorbital regions increased 2.132 ± 0.671 mL, and the retention rate was excellent (72.87 ± 10.23%). The GAIS showed a high score (2.5 ± 0.5 points), with patient self-assessment showing satisfactory results for all 7 questions on the questionnaire.

CONCLUSION

The high retention rate of SVF-gel suggests that it can provide an effective solution to tear trough deformity accompanied by infraorbital hollows.

Comparative Study of Three-Dimensional Volume Measurement for Facial Fat Grafting

ABSTRACT

The three-dimensional (3D) volume measurement after facial fat grafting is of great significance to plastic surgeons. It has been ascertained that reliable results rely on the accurate measurement of 3D softwares. Some 3D softwares in literatures have proposed various ways to optimize each step of the procedure, including the pre- and post-operative image acquisition, alignment, calculation, and analysis. Good image alignment between pre- and post-scan is essential to quantify the volumetric change. Once the pre- and post-operative image alignment has slightly bias or deviation, the subsequent volume measurement would also be affected. To our knowledge, 2 types of 3D software have been widely applied in clinic, primarily based on the image-automatically alignment and image-manually alignment. This study aimed to compare the accuracy, repeatability, and reproducibility of the Geomagic Qualify 12.0 software and the 3-Matic 7.0 software in a relatively ideal model of virtual facial fat grafting. A simulated facial fat grafting was first performed for 10 preoperative patients diagnosed with progressive hemifacial atrophy, and the known volumetric change was named as the true value (T value). Then, the facial volumetric change of every case was remeasured 10 times with above 2 kinds of software separately. The mean volumetric change was calculated as Q value and M value. The paired t test, intraclass correlation coefficient, and Bland-Altman analysis showed that the Geomagic Qualify 12.0 software demonstrated a statistically higher accuracy, repeatability, and reproducibility in comparison with the 3-Matic 7.0 software.

Total breast reconstruction using large-volume condensed and viable fat grafting after mastectomy

Autologous fat grafting (AFG) has become a third alternative for breast reconstruction after mastectomy. However, total breast reconstruction using AFG remains a great challenge. We performed breast reconstruction using large-volume condensed and viable fat grafting in 30 postmastectomy patients (irradiated, n = 9; nonirradiated, n = 21). The grafts were purified and condensed by the washing and cotton gauze rolling technique. The surgical maneuver is designed to preserve the grafts viability. Three-dimensional expansion was applied where strong adhesions were present. Seven patients wore the Brava device for the expansion of the recipient site. The mean (SD) volume of fat grafted in each procedure was 230.5 (57.8) mL. The average number of sessions was 3.3 (0.7). The irradiated patients required more sessions than the nonirradiated patients (p=.017). The mean follow-up period was 12.8 (4.3) months. One patient (3%) developed postoperative cellulitis. Cysts and palpable nodules occurred in eight patients (27%) and one patient (3%), respectively. Severe dermatitis and skin pigmentation change occurred in one patient wearing the Brava device. The esthetic scores significantly improved after the treatments (p<.001). Approximately 90% of the patients were satisfied. No local recurrence or remote metastasis was documented during the follow-up period. Our study showed the success of total breast reconstruction using AFG. As a third alternative for breast reconstruction, total breast reconstruction using large volume condensed and viable fat grafting is an effective and safe approach for postmastectomy patients.

Current state of the art in fat grafting: paradigm shift in surgical techniques and refinements in cleft and craniofacial reconstruction

PURPOSE OF REVIEW

The purpose of this review is to provide an update on current practice and trends in fat graft surgery. The present review covers postoperative fat graft survival and phases, recipient bed and fat tissue enrichment issues, the spectrum of clinical applications in the cleft-craniofacial field, surgical techniques, and predictive factors for different outcomes.

RECENT FINDINGS

Current investigations have led to a better understanding of fat graft survival and postoperative clinical progress. Fat grafting has been successfully adopted in a broad spectrum of cleft-related, craniofacial contour-related, burn-related, and radiation-related indications. Many variations on harvesting, processing, and delivery techniques and the use of recipient-site preconditioning and cell-enriched methods to increase the efficiency of fat grafting have been described, but little consensus exists about which technique is optimal. The development of predictors for fat grafting-related outcomes can aid multidisciplinary teams in providing better preoperative counseling, selecting the most suitable candidates for treatment, and establishing patient-specific postoperative care profiles.

SUMMARY

The addition of modern fat graft surgery to the surgeon's toolbox revolutionized the delivery of surgical cleft and craniofacial care. Further investigation is necessary to assist surgeons in selecting the best candidates and optimal techniques.

Volumetric Effect of Pregnancy on a Unilateral Facial Fat Graft

Weight gain can affect the volume of a facial fat graft, resulting in unfavorable asymmetries. Weight gain during pregnancy is more complex and does not just entail an increase in adipose tissue. This case report objectifies whether pregnancy results in volume changes of a facial fat graft. A 24-year-old woman received a fat graft (7 ml) in the mandibular area to mask a volume deficiency. This deficiency occurred after a fibula reconstruction of a mandibular defect resulting from the removal of an ameloblastoma. The patient became pregnant 3 weeks after the fat graft procedure. Standardized 3-dimensional photographs (3dMD) were available preoperatively and at 7 weeks (first trimester), 6 months (second trimester), 9 months (third trimester), and 14 months (4 months after delivery) postoperatively. Three-dimensional analysis revealed that no substantial volume changes of the fat graft occurred during pregnancy other than the overall proportional gain in facial volume. Pregnancy apparently does not affect the volume of a small unilateral fat graft applied in the facial region.

Facial aesthetic fat graft retention rates after filtration, centrifugation, or sedimentation processing techniques measured using three-dimensional surface imaging devices

OBJECTIVE

How to increase the long-term retention rate of autologous fat grafting has been widely discussed. This study aimed to evaluate long-term fat graft retention rates for the most widely used fat processing methods in the area of facial esthetic surgery, including centrifugation, filtration, and sedimentation, using three-dimensional (3D) imaging.

DATA SOURCES

PubMed, Embase, Wiley/Cochrane Library, and Web of Science databases were comprehensively searched from inception to July 2018 according to the guidelines of the American Society of Plastic Surgeons Fat Graft Task Force Assessment Methodology.

STUDY SELECTION

Articles were screened using predetermined inclusion and exclusion criteria. Data collected included patient characteristics, follow-up devices, fat grafting techniques, and clinical outcomes. Patient cohorts were pooled, and fat graft retention rates were calculated. Complications were summarized according to different clinical characteristics.

RESULTS

Of 77 articles, 10 clinical studies met the inclusion criteria and reported quantified measurement outcomes with 3D imaging which provide precise volumetric data with approximately 2% standard deviation compared to real volumes. Data of 515 patients were included. Fat grafting retention varied from 21% to 82%. We found filtration and centrifugation techniques could result in better retention outcomes. However, retention varied within each processing technique, with no significant difference among the 3 techniques. Twenty-two complications were reported among 515 patients, including donor-site hematoma (1 case), mild post-operative erythema (2 cases), mild volumetric asymmetries (2 cases), chronic edema (2 cases), overcorrection (2 cases), skin irregularity (6 cases), and headache or dysesthesia (7 cases).

CONCLUSIONS

Filtration and centrifugation techniques may result in better fat grafting retention outcomes than gravity sedimentation; however, more accurate statistical evidence is needed. Controversies continue to exist with respect to the performance of the different fat-processing techniques in fat graft retention.