Lipo layering of autologous fat: an improved technique with promising results

Improving the Retention Rate of Fat Grafting by Botulinum Toxin A: A Randomized, Self-controlled, Clinical Trial

BACKGROUND

Botulinum toxin A (BTX-A) can enhance the efficacy of fat grafting. However, most studies conducted animal experiments, lacked objective clinical data, or were non-randomized controlled trials. Thus, objective evaluation of the clinical effectiveness of BTX-A is still elusive.

METHODS

A randomized, self-controlled trial (2020-2022) on 16 patients who underwent bilateral autogenous fat breast augmentation was performed with each patient receiving autologous fat graft and BTX-A on one side and fat graft and equal volume of saline on the other side. All patients were followed. The effects of BTX-A were evaluated objectively by comparing the remaining bilateral fat graft volumes obtained through digital three-dimensional reconstruction. The improvement of each breast appearance and complication were assessed by the physician and patients who were blinded to the treatment.

RESULTS

The outcome of fat breast augmentation was evident for both sides at follow-up with no evidence of fat embolism, vascular/nervous injury, infection, and prolonged bruising. The analysis of the three-dimensional reconstruction data and assessments from both physicians and patients showed significant differences in the fat graft retention volume between the BTX-A side and the control side. No significant difference was found in the incidence of complications between the two sides.

CONCLUSIONS

Autogenous fat breast augmentation is safe and effective. This study shows that BTX-A can significantly improve the retention rate of fat transplantation, but cannot reduce complications. Trial registration This study was registered prior to patient enrollment (ClinicalTrials.gov identifier:ChiCTR2100054878).

LEVEL OF EVIDENCE IV

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Breast reconstruction through exclusive lipomodeling or in addition to a flap: Current status in Franche-Comté

INTRODUCTION

Breast reconstruction after cancer surgery through lipomodeling can be performed alone or in combination with a flap. Our objective is to describe the proportion of techniques used on patients who underwent autologous reconstructive surgery after tumorectomy or mastectomy in Franche-Comté.

MATERIALS AND METHODS

A bicentric retrospective observational study was conducted between October 2017 and December 2021 (NCT06101732), including three groups: those who underwent exclusive lipomodeling reconstruction after mastectomy (1) or in addition to a flap (2), and those who underwent exclusive lipomodeling reconstruction after tumorectomy (3). Socio-demographic, medical, and surgical data were collected and recorded in a specially designed software.

RESULTS

Two hundred and fifty-one lipomodeling procedures were performed on 91 patients. In group 1, the average transferred volume was 1191mL with an average number of sessions of 4.4 spreads over 19.4months. In group 2, the average transferred volume was 676mL with an average operative time of 2.5 spread over 16.1months. In group 3, the average transferred volume was 223mL with an average number of sessions of 1.5 spreads over 6.2months. Regarding postoperative complications, 11% had cysts of fat necrosis, 4.4% had infections, and 2.2% had hematomas.

CONCLUSION

Lipomodeling is a technique that has clearly established itself in the field of breast reconstructive surgery. It results in a few complications and improves the final aesthetic outcome whether used exclusively or in addition to a flap.

Improving Facial Fat Graft Survival Using Stromal Vascular Fraction-Enriched Lipotransfer: A Multicenter Randomized Controlled Study

BACKGROUND

Although previous clinical studies have reported that cell-assisted lipotransfer increases the fat survival rate in facial fat transplants, most were case studies without quantitative evaluation. A multicenter randomized controlled study was performed to evaluate the safety and efficacy of the stromal vascular fraction (SVF) in facial fat grafts.

METHODS

Twenty-three participants were enrolled for autologous fat transfer in the face, and assigned randomly to the experimental ( n = 11) or control ( n = 12) group. Fat survival was assessed using magnetic resonance imaging at 6 and 24 weeks postoperatively. Subjective evaluations were performed by the patients and surgeons. To address safety concerns, results of an SVF culture and the postoperative complications were recorded.

RESULTS

The overall fat survival rate was significantly higher in the experimental group than in the control group (6 weeks, 74.5% ± 9.99% versus 66.55% ± 13.77%, P < 0.025; 24 weeks, 71.27% ± 10.43% versus 61.98% ± 13.46%, P < 0.012). Specifically, graft survival in the forehead was 12.82% higher in the experimental group when compared with that in the control group at 6 weeks ( P < 0.023). Furthermore, graft survival in the forehead ( P < 0.021) and cheeks ( P < 0.035) was superior in the experimental group at 24 weeks. At 24 weeks, the aesthetic scores given by the surgeons were higher in the experimental group than in the control group ( P < 0.03); however, no significant intergroup differences were noted in the patient-evaluated scores. Neither bacterial growth from SVF cultures nor postoperative complications were noted.

CONCLUSION

SVF enrichment for autologous fat grafting can be a safe and effective technique for increasing the fat retention rate.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

BREAST-Q Patient-reported Outcomes in Different Types of Breast Reconstruction after Fat Grafting

Breast reconstruction after mastectomy improves patient quality of life. Independently of the type of reconstruction, ancillary procedures are sometimes necessary to improve results. Fat grafting to the breast is a safe procedure with excellent results. We report patient-reported outcomes using the BREAST-Q questionnaire after autologous fat grafting in different types of reconstructed breasts.

Methods

We performed a single-center, prospective, comparative study that compared patient-reported outcomes using the BREAST-Q in patients after different types of breast reconstruction (autologous, alloplastic, or after breast conserving) who subsequently had fat grafting.

Results

In total, 254 patients were eligible for the study, but only 54 (68 breasts) completed all the stages needed for inclusion. Patient demographic and breast characteristics are described. Median age was 52 years. The mean body mass index was 26.1 ± 3.9. The mean postoperative period at the administration of BREAST-Q questionnaires was 17.6 months. The mean preoperative BREAST-Q was 59.92 ± 17.37, and the mean postoperative score was 74.84 ± 12.48 (P < 0.0001). There was no significant difference when divided by the type of reconstruction.

Conclusion

Fat grafting is an ancillary procedure that improves the outcomes in breast reconstruction independently of the reconstruction type and heightens patient satisfaction, and it should be considered an integral part of any reconstruction algorithm.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

Objective

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

Methods

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

Results

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

Conclusion

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

Trial Registration Number

ChiCTR2100053663.

Autologous Fat Grafting with or without Processing: A Study in an Indian Clinical Context

Background:

Although fat grafting has become an attractive method of correction of soft tissue deficiencies, variability in results exists. As the understanding of mechanism of survival of graft improves, the concepts regarding fat grafting change. There are many ways to process the aspirated fat with no clear method superior.

Aim:

The aim of this study was to evaluate the role of processing during autologous fat transfer.

Materials and Methods:

The patients were serially divided into two groups, namely, A and B. Harvesting of lipoaspirate and injection of fat were same in both the groups. In group A, no processing was done. In group B, the fat was processed by sedimentation and injected. Patient satisfaction was assessed following the procedure and statistical analysis was done using the Mann–Whitney U-test.

Results:

Young females between 21 and 30 years formed the majority of patients who opted for fat grafting procedure. Most of the procedures were performed for defects in the face (93.3%). The most common indication of fat grafting was contour deformities, with abdomen being the most preferred donor site. The mean patients’ satisfaction following fat grafting without processing is 2.2 ± 0.68. The mean patients’ satisfaction following fat grafting with processing is 2.53 ± 0.99.

Conclusion:

There was not a statistically significant difference in patient outcomes following fat grafting, with or without processing, in terms of patient satisfaction. Autologous fat grafting was found to be a safe procedure with no significant complications.

Lipofilling as an aesthetic restorative technique for the facial hemiatrophy of Parry-Romberg syndrome: An analysis of 27 cases

•

Progressive haemifacial atrophy, also known as Parry-Romberg syndrome.

•

Lipofilling provides an option for voluminous flaps, improving skin quality and preserving the natural contours of the face.

•

Fat reinjection is a simple, efficient and reproducible procedure.

•

Physical appearance and psychological well-being should be considered as a part of the general management.

Introduction

The aim of this paper is to present our experience using autologous fat transplantation for facial augmentation and to evaluate the effectiveness of lipofilling in different regions of the face for the reconstruction and aesthetic improvement of the facial contouring.

Case presentation

Data in term to the age, gender distribution, harvest and injection sites, degree of satisfaction with post-surgical facial, and complications were recorded.

Discussion

Progressive haemifacial atrophy, also Known as Parry Romberg's disease, is a common craniofacial disease that conventionally affects the subcutaneous tissue on one side of the face. We report here a series of 27cases of hemifacial atrophy (Parry-Romberg syndrome), admitted to our department, and treated with lipofilling in conformity with Coleman's guidelines. The volume of fat grafting was assessed by an attempt to reach symmetry with the controlateral side within a single procedure.

Conclusion

All patients claimed that they were satisfied or very satisfied with the aesthetic results and affirmed that it had a positive psychological impact on their daily life.

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.

Cell-Assisted Lipotransfer for Cosmetic Breast Augmentation: Supportive Use of Adipose-Derived Stem/Stromal Cells

BACKGROUND

Lipoinjection is a promising treatment but has some problems, such as unpredictability and a low rate of graft survival due to partial necrosis.

METHODS

To overcome the problems with lipoinjection, the authors developed a novel strategy known as cellassisted lipotransfer (CAL). In CAL, autologous adiposederived stem (stromal) cells (ASCs) are used in combination with lipoinjection. A stromal vascular fraction (SVF) containing ASCs is freshly isolated from half of the aspirated fat and recombined with the other half. This process converts relatively ASC-poor aspirated fat to ASC-rich fat. This report presents the findings for 40 patients who underwent CAL for cosmetic breast augmentation.

RESULTS

Final breast volume showed augmentation by 100 to 200 ml after a mean fat amount of 270 ml was injected. Postoperative atrophy of injected fat was minimal and did not change substantially after 2 months. Cyst formation or microcalcification was detected in four patients. Almost all the patients were satisfied with the soft and natural-appearing augmentation.

CONCLUSIONS

The preliminary results suggest that CAL is effective and safe for soft tissue augmentation and superior to conventional lipoinjection. Additional study is necessary to evaluate the efficacy of this technique further.

Radiation-Induced Skin Fibrosis: Pathogenesis, Current Treatment Options, and Emerging Therapeutics

Radiotherapy (RT) has become an indispensable part of oncologic treatment protocols for a range of malignancies. However, a serious adverse effect of RT is radiodermatitis; almost 95% of patients develop moderate to severe skin reactions following radiation treatment. In the acute setting, these can be erythema, desquamation, ulceration, and pain. Chronically, soft tissue atrophy, alopecia, and stiffness can be noted. Radiodermatitis can delay oncologic treatment protocols and significantly impair quality of life. There is currently a paucity of effective treatment options and prevention strategies for radiodermatitis. Importantly, recent preclinical and clinical studies have suggested that fat grafting may be of therapeutic benefit, reversing detrimental changes to soft tissue following RT. This review outlines the damaging effects of RT on the skin and soft tissue as well as discusses available treatment options for radiodermatitis. Emerging strategies to mitigate detrimental, chronic radiation-induced changes are also presented.

A systematic review of the effectiveness and complications of fat grafting in the facial region

INTRODUCTION

The objective of this study was to evaluate the safety and efficacy of fat grafting to the facial region for the reconstruction and aesthetic enhancement of facial contour.

METHODS

A systematic literature review of the National Library of Medicine (PubMed), MEDLINE and Cochrane databases was performed. Studies involving the outcomes of autologous fat grafting to correct or enhance contour defects of the face were included. Extracted data included patient demographics, harvest and injection sites, graft harvesting and injection technique, mean injected volume, retained volume percentage and complications.

RESULTS

Forty-three articles met the inclusion criteria, resulting in 4577 patients with various facial contour defects treated with autologous fat grafting. Injection sites were categorized by anatomic facial regions as upper (32.5%), middle (53%) and lower face (14.5%). The mean volume of injected fat was 16.9 ml. The mean weighted volume retention of non-enriched grafts was 41.63% at the time of follow up (mean 13.9 months). A total of 104 (2.27%) complications were reported including asymmetry (74), skin irregularities (14), prolonged edema (4), graft hypertrophy (4), fat necrosis (3), infection (2), erythema (1), telangiectasia (1), and activation of acne (1).

CONCLUSION

The present study represents the first systematic review of fat grafting in the facial region, a widely-performed procedure within plastic surgery practice. Importantly, it presents pooled important data such as retained grafting volume and complication rates in this anatomical region, providing clinicians with more accurate information with which to guide their decision-making and patient education.

Effect of Decantation Time on Viability and Apoptosis in Adipocytes After Liposuction

BACKGROUND

The effect of decantation time on viability and apoptosis in adipocytes has not been described. The objective of the study was to describe viability and apoptosis in adipocytes up to 2 h after harvesting.

METHODS

Twenty patients who underwent esthetic liposuction from the abdomen were included. The lipoaspirate was obtained from the infra-umbilical area with the tumescent technique. Liposuction was performed with a 60-ml syringe and a 3-ml cannula. Lipoaspirates were centrifuged at 50 g for 5 min at 0, 60 and 120 min after harvesting. One gram of fat was digested with 0.1% type 1 collagenase and incubated at 37 degrees for 30 min. Adipocytes were counted on 10 random microscopic fields. Apoptosis was determined by TUNEL assay. A fluorescence microscope was used to visualize the staining nuclei and cells.

RESULTS

Regarding viability, immediately after harvesting, 57.6 ± 18.9% of the cells were viable, whereas 60 min after liposuction the viability decreased to 51.62 ± 8.8% and 120 min after liposuction the percentage of viable cells was 46.8 ± 16.9%. The percentage of apoptotic cells at time 0 was 38.2 ± 8.0%, whereas it was 51.24 ± 8.1% at 60 min and 62.9 ± 16.1% at 120 min after collection.

CONCLUSIONS

Apoptosis and mortality of adipocytes after liposuction increase directly proportional to the time of decantation. Lipoinjection should be performed as soon as possible after harvesting.

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 .

Platelet-Rich Plasma for Skin Rejuvenation and Tissue Fill

Platelet preparations, including platelet-rich plasma and platelet-rich fibrin matrix, have been used to improve wound healing, recovery time, and cosmetic outcomes for facial rejuvenation. Bioactive growth factors released from platelets are the putative agents in producing a reparative tissue reaction in the treated area. Different methods of processing the patients' blood will yield different types of platelet preparations with different components and properties, and it is important to understand these differences and their potential implications. More robust studies are necessary to better understand the nuances of these preparations and their optimal use.

Association of Fat Grafting With Patient-Reported Outcomes in Postmastectomy Breast Reconstruction

Importance

Fat grafting has proven to be a useful adjunct to breast reconstruction for the treatment of contour irregularities and volume deficits, but the proposed US Food and Drug Administration regulations may severely limit the ability of plastic surgeons to continue its use in this clinical context.

Objective

To determine whether fat grafting is associated with patient-reported outcomes (PROs) in patients undergoing breast reconstruction.

Design, Setting, and Participants

A longitudinal, multicenter, prospective cohort study was conducted between February 1, 2012, and July 31, 2016, at the 11 sites associated with the Mastectomy Reconstruction Outcomes Consortium Study. Eligible patients included women 18 years or older presenting for breast reconstruction after mastectomy with 2 years or more of follow-up. All primary procedure types (implant based and flap based) were eligible. Patients were excluded if they had not completed breast mound reconstruction by 1 year after starting reconstruction.

Interventions

Fat grafting as an adjunct to breast mound reconstruction.

Main Outcomes and Measures

Primary end points were patient-reported outcome measures as assessed by the validated BREAST-Q survey, with higher scores on a 0- to 100-point scale indicating better health-related quality of life. Survey subscales included breast satisfaction, as well as psychosocial, physical, and sexual well-being. Patient-reported outcomes were compared between those who received and did not receive fat grafting.

Results

A total of 2048 women were included (mean [SD] age, 49.4 [10] years), with 165 (8.1%) undergoing fat grafting between years 1 and 2. One year postoperatively, patients who later underwent fat grafting reported significantly lower breast satisfaction (adjusted mean difference [AMD], -4.74; 95% CI, -8.21 to -1.28; P = .008), psychosocial well-being (AMD, -3.87; 95% CI, -7.33 to -0.40; P = .03), and sexual well-being (AMD, -5.59; 95% CI, -9.70 to -1.47; P = .008), compared with those who did not receive subsequent fat grafting. Following the procedure, the fat-grafted cohort reported similar breast satisfaction (AMD, -0.68; 95% CI, -4.42 to 3.06; P = .72), psychosocial well-being (AMD, -0.59; 95% CI, -3.92 to 2.74; P = .73), and sexual well-being (AMD, -2.94; 95% CI, -7.01 to 1.12; P = .15) 2 years postoperatively.

Conclusions and Relevance

Fat grafting may improve breast satisfaction, psychosocial well-being, and sexual well-being in patients undergoing breast reconstruction.

Botulinum toxin A improves adipose tissue engraftment by promoting cell proliferation, adipogenesis and angiogenesis

Adipose tissue engraftment has become a well-established therapy in plastic and reconstructive surgery used to restore age-related or injury-related soft tissue loss. However, the unpredictable absorption rates limit its further application. Some clinicians have noted that more optimal aesthetic results are achieved when botulinum toxin A (BoNTA) is applied prior to adipose tissue grafting. In the present study, we transplanted allogeneic adipose tissue treated with or without BoNTA in SD rats in vivo. We subsequently evaluated the survival rate (weight, volume, apoptosis and cellular integrity) and revascularization of the adipose tissue. The results revealed that BoNTA improved the long-term weight and volume retention of the graft, and preserved cellular integrity. BoNTA significantly increased the expression levels of CD31 and vascular endothelial growth factor (VEGF), suggesting enhanced vasodilation and endothelial cell proliferation. In vitro, adipose-derived stem cells (ASCs) were isolated, identified and induced to proliferate and differentiate with or without BoNTA. Furthermore, to evaluate the proliferative, adipogenic and angiogenic ability of the ASCs, CCK-8 assay and Oil Red O staining were conducted. Gene and protein expression levels were analyzed by RT-qPCR and western blot analysis. The results revealed that 8×10⁻² U/ml BoNTA as the optimal dose increased ASC proliferation and adipogenic differentiation capacity, as well as the expression level of the key cytokine of angiogenesis. On the whole, our findings indicate that BoNTA improves adipose tissue engraftment and promotes ASC regeneration, which could benefit future clinical applications.

Systematic review: The oncological safety of adipose fat transfer after breast cancer surgery

OBJECTIVES

Oncological concerns have risen around the safety of adipose fat transfer (AFT) after breast cancer surgery. In this article, we present the clinical and molecular evidences, and discuss the current contradiction between them.

MATERIALS AND METHODS

Every clinical trial and experimental study on AFT and its oncological influences was screened. Between September 2014 and September 2016, 856 articles from four databases were found. 105 core articles were selected.

RESULTS

A total of 18 clinical studies have been published. The loco-regional recurrence (LRR) incidence rates range between 0 and 3.90% per year. For the mastectomy and breast conservative therapy group separately, a LRR per year between 0 and 1.62% and 0-3.90 has been reported, respectively. Some studies included a matched control group and found no significant difference between cases and controls, with the exception of a subgroup of patients with intraepithelial breast carcinoma. Adipose derived mesenchymal stem cells have a potential oncogenic effect on residual cancer cells after breast cancer surgery. Numerous signalling proteins and pathways have been described that can stimulate tumour initiation and growth.

CONCLUSION

There is a contradiction between experimental and clinical findings. Numerous adipokines have been discovered that could potentially promote tumour initiation and growth, but clinical studies fail to point out a significant increase in LRR in patients who receive AFT after breast cancer surgery. More prospective studies are needed with a sufficient follow-up time and analysis of some critical factors, such as adjuvant radiotherapy and hormonal therapy, the origin and volume of the injected fat, and genetic influences.

Evaluating Autologous Lipofilling for Parry-Romberg Syndrome–Associated Defects: A Systematic Literature Review and Case Report

Background

Parry-Romberg syndrome (PRS) is a rare craniofacial disease that causes progressive hemifacial atrophy of the soft tissue before spontaneously entering remission. Autologous fat grafting may provide a less invasive alternative, producing aesthetically pleasing results while avoiding the need for traditional microsurgical free flap coverage.

Methods

A systematic review of the literature was conducted. Inclusion and exclusion criteria were applied. The case report highlights the technique using two-dimensional and three-dimensional photography.

Results

Our review yielded 31 articles in addition to our case describing 147 cases of lipofilling to correct PRS soft-tissue defects. Patients underwent an average of 2.2 procedures, receiving on average 95 mL of grafted fat. Disease severity was classified into mild (41%), moderate (42%), and severe (17%) in the identified patients. Increasing disease severity correlated with an increasing number of procedures and fat-grafting volumes to achieve adequate aesthetic outcomes (mean, 1.5 and 38 mL; 2.3 and 81 mL; 3.7 and 129 mL, respectively). Reported benefits over flap-based reconstructions included reductions in cost (40%), operative time (50%), donor-site morbidity (52%), and rate of complications (33%). Aesthetic benefits cited included improved skin quality (65%), more natural contours (1%), and more natural facial expressions (10%).

Conclusion

Fat grafting for correction of PRS-associated soft-tissue defects is receiving heightened acceptance for its ability to restore natural facial contours. While additional fat-grafting procedures may be required with increased disease severity, autologous fat grafting may be a beneficial option as a sole modality to correct PRS-associated soft-tissue atrophy.

Prospective 1-Year Follow-Up Study of Breast Augmentation by Cell-Assisted Lipotransfer

BACKGROUND

Breast augmentation by cell-assisted lipotransfer (CAL) may achieve a more natural breast contour than silicone implants. Moreover, certain complications associated with these prosthetic devices can be avoided with CAL. Few prospective studies of CAL have been performed to examine long-term volume changes, effects on breast parenchymal tissue, and the effect of stromal vascular fraction (SVF) on graft survival.

OBJECTIVES

In a 1-year prospective study of patients who underwent CAL, the authors examined changes in breast volume, effects on parenchymal tissue, and the impact of SVF on graft survival.

METHODS

Following preoperative radiologic examination, patients underwent primary augmentation mammaplasty by CAL to both breasts. The SVF was characterized, and changes in breast volume were determined from magnetic resonance imaging studies performed postoperatively at 3 months and 1 year. A breast-imaging specialist reviewed all scans to detect changes in breasts.

RESULTS

Five patients (10 breasts) were enrolled. Averagely 23% of grafted fat in volume was additionally harvested from each patient to isolate SVF cells. One year after CAL, breast volume had decreased to 47% of the initial postoperative volume. There was no parenchymal changes except small oil cysts. The ratio of SVF cell count to grafted fat volume showed no correlation with graft survival. Patterns of breast-volume decrease differed between older women with a history of breastfeeding and younger women without a history of breastfeeding.

CONCLUSIONS

The addition of SVF cells did not appear to improve the retention of grafted fat in these patients. Skin tension may be an important factor influencing the absorption pattern of grafted fat. LEVEL OF EVIDENCE 4: Therapeutic.

Fat grafting: a citation analysis of the seminal articles

Background:

There has been substantial rise in the volume of published works on fat transfer in the medical literature in the past 25 years, and this is indicative of its growing popularity. However, many unanswered questions remain, and there is no consensus as to the optimum technique. Consequently, the scientific and clinical research on fat grafting continues to increase rapidly. The purpose of our study was to perform a bibliometric analysis of the most-cited articles in fat transfer.

Methods:

Through the Web of Science, all articles relating to fat grafting were identified in the plastic and reconstructive literature. The 100 most-cited articles were identified and analyzed individually.

Results:

Total citations ranged from 35 to 363 and the most-cited paper by Sidney Coleman was published in Plastic and Reconstructive Surgery. The United States produced 46% of the most-cited papers, and the University of California was the most prolific institution. Twenty-one articles focused on lipofilling to the face while 14 articles looked at fat grafting to the breast.

Conclusions:

The scientific relevance of a published work is reflected in the number of citations from peers that it receives. Therefore, the 100 most-cited papers in fat grafting have been the most influential articles on this field, and they are likely to be the ones that are remembered most.

Autologous fat grafting for breast augmentation in underweight women

BACKGROUND

In recent years, there have been reports of success with autologous fat grafting to the breast for cosmetic breast enhancement. However, the procedure is generally contraindicated in women who are underweight (body mass index [BMI]<18.5).

OBJECTIVES

The author sought to determine the safety and success rate of autologous fat grafting for breast augmentation in underweight women.

METHODS

Patients who underwent breast augmentation with autologous fat grafting and had adequate follow-up time (≥12 months) were assigned to group A (BMI>18.5) or group B (BMI≤18.5; underweight). A retrospective analysis was performed to compare the safety and effectiveness of fat grafting between the study groups.

RESULTS

Relative to group A, patients in group B were younger and had smaller differences in breast circumference (BCD) both pretreatment and posttreatment. The volume of injected fat was significantly smaller in group B. The differences in posttreatment complication rates and changes in BCD were not statistically significant between the study groups.

CONCLUSIONS

The same degree of breast enlargement was achieved in both study groups after autologous fat grafting for breast augmentation. The rate of posttreatment complications was not higher for underweight women. Therefore, it appears that BMI≤18.5 is not a contraindication for this procedure.

LEVEL OF EVIDENCE

4.

Breast reconstruction de novo by water-jet assisted autologous fat grafting--a retrospective study

BACKGROUND

Autologous fat grafting has become a frequent, simple, reproducible and low-risk technique for revisional or partial breast reconstruction. The presented European multicenter study describes an optimized treatment and follow-up protocol for the de novo breast reconstruction after total mastectomy by lipotransfer alone.

METHODS

A retrospective European multicenter trial included 135 procedures on 28 (35 breasts) postmastectomy patients (mean 52.4 years). All women were treated with the water-jet assisted fat grafting method (BEAULI™) combined with additional procedures (NAC reconstruction, contralateral mastoplasty) and evaluated with at least 6 months follow-up (mean 2.6 years). Sonography or mammography, clinical examination, patient questionnaire (10-point Likert scale) and digital photographs were carried out.

RESULTS

On average the patients received 4 to 6 procedures each with a single volume of 159 ml (±61 ml) over 21 months (range 9 months to 2.5 years). In total 1,020 ml (±515 ml) fat were grafted till a complete breast reconstruction was achieved. Irradiated patients needed a significantly higher volume than non-irradiated (p<0.041). Main treatment complications were liponecrosis (2.59%), infection (0.74%) and granuloma (0.74%). Patient satisfaction was overall high to very high (96%) and confirmed the good aesthetic results (68%) and the natural softness, contour and shape of the reconstructed breast.

CONCLUSIONS

A complete breast reconstruction with large volume fat grafting is alternatively possible to standard techniques in selected cases. It takes at least 4 to 6 lipotransfers in the course of 2 years. Patients with prior radiotherapy may require even up to 8 sessions over nearly 3 years of treatment.

Use of autologous fat grafting for reconstruction postmastectomy and breast conserving surgery: a systematic review protocol

INTRODUCTION

There is growing interest in the potential use of autologous fat grafting (AFG) for the purposes of breast reconstruction. However, concerns have been raised regarding the technique's clinical effectiveness, safety and interference with screening mammography. The objective of this systematic review was to determine the oncological, clinical, aesthetic and functional, patient reported, process and radiological outcomes for AFG.

METHODS AND ANALYSIS

All original studies, including randomised controlled trials, cohorts studies, case-control studies, case series and case reports involving women undergoing breast reconstruction. All AFG techniques performed for the purposes of reconstruction in the postmastectomy or breast conserving surgery setting will be considered. Outcomes are defined within this protocol along; oncological, clinical, aesthetic and functional, patient reported, process and radiological domains. The search strategy has been devised to find papers about 'fat grafting and breast reconstruction' and is outlined within the body of this protocol. The full search strategy is outlined within the body of the protocol. The following electronic databases will be searched from 1 January 1986 to 6 June 2013: PubMed, MEDLINE, EMBASE, SCOPUS, CINAHL, PsycINFO, SciELO, The Cochrane Library, including the Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Register of Controlled Trials (CENTRAL), Database of Abstracts of Reviews of Effect (DARE), the Cochrane Methodology Register, Health Technology Assessment Database, the NHS Economic Evaluation Databases and Cochrane Groups, ClinicalTrials.gov, Current Controlled Trials Database, the World Health Organisation (WHO) International Clinical Trials Registry Platform, UpToDate.com, NHS Evidence and the York Centre for Reviews and Dissemination. Grey literature searches will also be conducted as detailed in our review protocol. Eligibility assessment occurred in two stages, title and abstract screening and then full text assessment. Data were extracted and stored in a database with standardised extraction fields to facilitate easy and consistent data entry.

ETHICS AND DISSEMINATION

This systematic review will be published in a peer-reviewed journal. It will also be presented at national and international conferences in the fields of plastic, reconstructive and aesthetic surgery and at more general surgical and methodological conferences. It will be disseminated electronically and in print. Brief reports of the review findings will be disseminated directly to the appropriate audiences of surgeons and societies through email and other modes of communication. Updates of the review will be conducted to inform and guide healthcare practice and policy.

PROTOCOL REGISTRATION

PROSPERO-National Institute of Health Research (NIHR) Prospective Register of Systematic Reviews (CRD42013005254).

Magnetic resonance imaging and ultrasound evaluation after breast autologous fat grafting combined with platelet-rich plasma

BACKGROUND

Breast lipofilling is a fairly simple and safe procedure if it is performed by experienced surgeons.

METHODS

The authors evaluated the radiologic findings from 24 breasts (15 women) subjected to a lipofilling procedure (two sessions) for corrective surgery or cosmetic reasons. Mammography, ultrasound, and magnetic resonance imaging were performed before the first lipofilling session (T0) and 12 months after the last session (T12); ultrasound and magnetic resonance imaging were used 3 months after the first session (Ti) and 3 and 6 months after the last session (T3 and T6). Volumetric evaluations were also made through three-dimensional magnetic resonance imaging reconstruction.

RESULTS

Ultrasound showed oily cysts in 66.67 percent of the breasts at Ti, 70.83 percent at T3, 62.5 percent at T6, and 45.83 percent at T12, whereas magnetic resonance imaging detected oily cysts in 8.33 percent at Ti and T3 and T6 months and 4.17 percent at T12. At Ti, T3, and T6, the cytosteatonecrotic areas identified on both ultrasound and magnetic resonance imaging were unchanged (8.33 percent), whereas at T12 those cytosteatonecrotic areas were increased on ultrasound (12.5 percent) and even more on the magnetic resonance imaging scans (16.67 percent). The average resorption percentage of injected volume was 15.36 percent at T6 months and 28.23 percent at T12 months.

CONCLUSIONS

Postlipofilling breast changes can be distinguished from malignant alterations by experienced radiologists and need not interfere with early cancer diagnosis if patients are checked regularly. Moreover, magnetic resonance imaging is very useful for breast volume assessments and for detecting possible changes during longitudinal study.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Grading lipoaspirate: is there an optimal density for fat grafting?

BACKGROUND

Clinical results of fat grafting have been unpredictable. In this article, the authors hypothesize that centrifugation creates "graded densities" of fat with varying characteristics that influence lipoaspirate persistence and quality.

METHODS

Aliquots of human female lipoaspirate (10 cc) were centrifuged for 3 minutes at 1200 g. The bloody and oil fractions were discarded. Subsequently, 1.0 cc of the highest density and lowest density fat was separated for lipoinfiltration or analysis. Highest density or lowest density fat grafted into adult FVB mice was harvested at 2 and 10 weeks to quantify short- and long-term persistence, respectively. Progenitor cell number and expression of vascular endothelial growth factor, stromal cell-derived factor-1α, platelet-derived growth factor, and adiponectin were analyzed by flow cytometry and enzyme-linked immunosorbent assay, respectively.

RESULTS

Greater percentages of highest density fat grafts remain at 2 and 10 weeks after injection compared with lowest density fat grafts (85.4 ± 1.9 percent versus 62.3 ± 0.1 percent, p = 0.05; and 60.8 ± 4.9 versus 42.2 ± 3.9, p < 0.05, respectively). Highest density fractions contain more progenitor cells per gram than lowest density fractions (2.0 ± 0.2-fold increase, p < 0.01). Furthermore, concentrations of vascular endothelial growth factor, stromal vascular fraction, platelet-derived growth factor, and adiponectin are all elevated in highest density compared with lowest density fractions (34.4 percent, p < 0.01; 34.6 percent, p < 0.05; 52.2 percent, p < 0.01; and 45.7 percent, p < 0.05, respectively).

CONCLUSIONS

Greater percentages of highest density fractions of lipoaspirate persist over time compared with lowest density fractions. A vasculogenic mechanism appears to contribute significantly, as highest density fractions contain more progenitor cells and increased concentrations of several vasculogenic mediators than lowest density fractions.

Facial Soft Tissue Augmentation using Autologous Fat Mixed with Stromal Vascular Fraction

Background

Autologous fat grafting evolved over the twentieth century to become a quick, safe, and reliable method for restoring volume. However, autologous fat grafts have some problems including uncertain viability of the grafted fat and a low rate of graft survival. To overcome the problems associated with autologous fat grafts, we used uncultured adipose tissue-derived stromal cell (stromal vascular fraction, SVF) assisted autologous fat grafting. Thus, the purpose of this study was to evaluate the effect of SVF in a clinical trial.

Methods

SVF cells were freshly isolated from half of the aspirated fat and were used in combination with the other half of the aspirated fat during the procedure. Between March 2007 and February 2008, a total of 9 SVF-assisted fat grafts were performed in 9 patients. The patients were followed for 12 weeks after treatment. Data collected at each follow-up visit included clinical examination of the graft site(s), photographs for historical comparison, and information from a patient questionnaire that measured the outcomes from the patient perspective. The photographs were evaluated by medical professionals.

Results

Scores of the left facial area grafted with adipose tissue mixed with SVF cells were significantly higher compared with those of the right facial area grafted with adipose tissue without SVF cells. There was no significant adverse effect.

Conclusions

The subjective patient satisfaction survey and surgeon survey showed that SVF-assisted fat grafting was a surgical procedure with superior results.

Applicability and safety of autologous fat for reconstruction of the breast

BACKGROUND

Autologous fat grafting to the breast for cosmetic and reconstructive purposes is still controversial with respect to its safety and efficacy. The objective of this study was to conduct a systematic review of the clinical applicability and safety of the technique.

METHODS

An online search of the Cochrane Library, MEDLINE, Embase and SciELO was conducted from July 1986 to June 2011. Studies included in the review were original articles of autologous liposuctioned fat grafting to the female breast, with description of clinical complications and/or radiographic changes and/or local breast cancer recurrence.

RESULTS

This review included 60 articles with 4601 patients. Thirty studies used fat grafting for augmentation and 41 for reconstructive procedures. The incidence of clinical complications, identified in 21 studies, was 3·9 per cent (117 of 3015); the majority were induration and/or palpable nodularity. Radiographic abnormalities occurred in 332 (13·0 per cent) of 2560 women (17 studies); more than half were consistent with cysts. Local recurrence of breast cancer (14 of 616, 2·3 per cent) was evaluated in three studies, of which only one was prospective.

CONCLUSION

There is broad clinical applicability of autologous fat grafting for breast reconstruction. Complications were few and there was no evidence of interference with follow-up after treatment for breast cancer. Oncological safety remains unclear.

Adipose tissue engineering: three different approaches to seed preadipocytes on a collagen-elastin matrix

BACKGROUND

Millions of plastic and reconstructive surgical procedures are performed each year to repair soft-tissue defects that result from significant burns, tumor resections, or congenital defects. Tissue-engineering strategies have been investigated to develop methods for generating soft-tissue. Preadipocytes represent a promising autologous cell source for adipose tissue engineering. These immature precursor cells, which are located between the mature adipocytes in the adipose tissue, are much more resistant to mechanical stress and ischemic conditions than mature adipocytes. To use preadipocytes for tissue-engineering purposes, cells were isolated from human adipose tissue and seeded onto scaffolds. Once processed, preadipocytes become subject to the human tissue act and require handling under much tighter regulations. Therefore, we intended to identify any influence caused by processing of preadipocytes prior to seeding on the reconstructed adipose tissue formation.

MATERIAL AND METHOD

Human preadipocytes were isolated from subcutaneous adipose tissue obtained from discarded tissue during abdominoplasties of healthy men and women. Preadipocytes were divided into 3 groups. Cells of group I were seeded onto the scaffold directly after isolation, cells of group II were proliferated for 4 days before seeding, and cells of group III were proliferated and induced to differentiate before seeded onto the scaffold. A 3-dimensional scaffold (Matriderm, Dr. Otto Suwelack Skin and Health Care GmbH, Billerbeck, Germany) containing bovine collagen and elastin served as a carrier. Fourteen days after isolation, all scaffolds were histologically evaluated, using hematoxylin and eosin, anti-Ki-67 antibody, as well as immunofluorescence labeling with Pref-1 antibody (DLK (C-19), peroxisome proliferator-activated receptor gamma antibody, and DAPI (4',6-diamidino-2-phenylindole).

RESULTS

Cells of all groups adhered to the scaffolds on day 21 after isolation. Cells of groups I (freshly isolated preadipocytes) and II (proliferated preadipocytes) adhered well and penetrated into deeper layers of the matrix. In group III (induced preadipocytes), penetration of cells was primarily observed to the surface area of the scaffold.

DISCUSSION/CONCLUSION

: The collagen-elastin matrix serves as a useful scaffold for adipose tissue engineering. Freshly isolated preadipocytes as well as proliferated preadipocytes showed good penetration into deeper layers of the scaffold, whereas induced preadipocytes attached primarily to the surface of the matrix. We conclude that there might be different indications for each approach.

Current applications and safety of autologous fat grafts: a report of the ASPS fat graft task force

TASK FORCE STATEMENT: In 2007, the American Society of Plastic Surgeons formed a task force to conduct an assessment regarding the safety and efficacy of autologous fat grafting, specifically to the breast, and to make recommendations for future research. The task force formulated specific issues regarding fat grafting and then compiled them to focus on five broad-based questions: 1. What are the current and potential applications of fat grafting (specifically breast indications, and if data are available, other cosmetic and reconstructive applications)? 2. What risks and complications are associated with fat grafting? 3. How does technique affect outcomes, including safety and efficacy, of fat grafting? 4. What risk factors need to be considered for patient selection at this level of invasiveness? 5. What advancements in bench research/molecular biology potentially impact current or future methods of fat grafting? To answer these questions, the task force reviewed the scientific literature, critically appraised the information available, and developed evidence-based practice recommendations. Although the primary issue of interest was fat grafting to the breast, other aspects of fat grafting were evaluated.

Progenitor-enriched adipose tissue transplantation as rescue for breast implant complications

Breast enhancement with artificial implants is one of the most frequently performed cosmetic surgeries but is associated with various complications, such as capsular contracture, that lead to implant removal or replacement at a relatively high rate. For replacement, we used transplantation of progenitor-supplemented adipose tissue (cell-assisted lipotransfer; CAL) in 15 patients. The stromal vascular fraction containing adipose tissue progenitor cells obtained from liposuction aspirates was used to enrich for progenitor cells in the graft. Overall, clinical results were very satisfactory, and no major abnormalities were seen on magnetic resonance imaging or mammogram after 12 months. Postoperative atrophy of injected fat was minimal and did not change substantially after 2 months. Surviving fat volume at 12 months was 155 +/- 50 mL (Right; mean +/- SD) and 143 +/- 80 mL (Left) following lipoinjection from an initial mean of 264 mL. These preliminary results suggest that CAL is a suitable methodology for the replacement of breast implants.

Post-mastectomy breast reconstruction: a history in evolution

Although the need for mastectomy has been evident for many years, postmastectomy reconstruction has been recognized as an achievable outcome for only a little over a century. A review of the evolution of both autologous and prosthetic options for reconstruction was undertaken. The earliest attempts at reconstruction used autologous techniques that were either unsuccessful, not reproducible, or were associated with significant morbidity. Prosthetic techniques became sought after, with silicone prostheses widely used until concerns about potential adverse effects led to the investigation of alternate options. With these concerns shown to be unfounded, silicone and saline prostheses evolved with successive generations of implants. Concurrent advances in reconstructive surgery led to a revival in autologous techniques for breast reconstruction, with microsurgical free-tissue transfer potentiating a new range of potential donor sites. The abdominal wall became the donor site of choice, and with the advent of perforator flaps, morbidity associated with flap harvest was minimized. In cases where the abdominal wall is unsuitable, flaps such as the superior and inferior gluteal artery perforator flaps, the musculocutaneous gracilis flap, and the "stacked" deep inferior epigastric artery perforator flap are frequently used options. The development of minimally invasive techniques for implant placement and flap harvest, such as endoscopy, continue to evolve, and research in tissue engineering offers a vision for a future without the need for a donor site.

Correction of hemifacial atrophy with autologous fat transplantation

BACKGROUND

Autologous fat transplantation has frequently been used by many surgeons for facial recontouring in esthetic patients, with good long-term results. However, this technique has not been used primarily in treating patients with hemifacial atrophy, and its efficacy and long-term outcome remain unknown.

METHODS

In a 7-year period, 31 patients with hemifacial atrophy were treated with autologous fat transplantation in our institution. All patients had been in their stable phase of the disease for at least 1 year. Autologous fat grafts were harvested from the lower abdomen or thigh with our preferred low-pressure syringe technique and then spun at the lower speed. The fat grafts were injected into multiple areas in multiple tissue planes and tunnels to the diseased side of the face. The same procedure was repeated once or twice as necessary after each injection in at least 3 months. All patients were followed up to 5 years, and their outcomes were evaluated by the patients, plastic surgeons, and laypersons separately.

RESULTS

Obviously improved facial contour was evident in most patients after autologous fat transplantations. More than 65% of the patients in this series were assessed as satisfactory by all 3 groups. Between 10% and 30% of the patients were mostly satisfactory. Only less than 7% of the patients were unsatisfactory. No complications were seen in either donor sites or recipient sites in this series.

CONCLUSIONS

Autologous fat transplantation can be a good treatment of choice for patients with hemifacial atrophy.

Cell-assisted lipotransfer for cosmetic breast augmentation: supportive use of adipose-derived stem/stromal cells

BACKGROUND

Lipoinjection is a promising treatment but has some problems, such as unpredictability and a low rate of graft survival due to partial necrosis.

METHODS

To overcome the problems with lipoinjection, the authors developed a novel strategy known as cell-assisted lipotransfer (CAL). In CAL, autologous adipose-derived stem (stromal) cells (ASCs) are used in combination with lipoinjection. A stromal vascular fraction (SVF) containing ASCs is freshly isolated from half of the aspirated fat and recombined with the other half. This process converts relatively ASC-poor aspirated fat to ASC-rich fat. This report presents the findings for 40 patients who underwent CAL for cosmetic breast augmentation.

RESULTS

Final breast volume showed augmentation by 100 to 200 ml after a mean fat amount of 270 ml was injected. Postoperative atrophy of injected fat was minimal and did not change substantially after 2 months. Cyst formation or microcalcification was detected in four patients. Almost all the patients were satisfied with the soft and natural-appearing augmentation.

CONCLUSIONS

The preliminary results suggest that CAL is effective and safe for soft tissue augmentation and superior to conventional lipoinjection. Additional study is necessary to evaluate the efficacy of this technique further.

Autologous In Vivo Adipose Tissue Engineering in Hyaluronan-Based Gels—A Pilot Study

BACKGROUND

There is a major clinical need for strategies for adequately reconstructing the soft tissue defects found after deep burns, tumor resection, or trauma. A promising solution is adipose tissue engineering with preadipocytes, stem-cell derived precursors of the adipose tissue, implanted within biomaterials. This pilot study evaluated hyaluronan gels mixed with autologous undifferentiated preadipocytes in a pig model for their potency to generate new fat.

MATERIALS AND METHODS

Preadipocytes were isolated from intra-abdominal pig fat by collagenase digestion, plated on fibronectin-coated culture dishes in Dulbecco's modified Eagle medium/Ham's F12 (Biochrom, Berlin, Germany) combined with 10% pig serum, expanded, and mixed with hyaluronan gel. Two types of gels with varying degrees of amidation of the carboxyl groups were tested (HYADD3, HYADD4). Cell-loaded gels and unseeded controls were injected subcutaneously into the ears of three pigs, explanted at 6 wk, and analyzed histologically.

RESULTS

Both cell-loaded specimens were detected macroscopically. They demonstrated a slight volume effect with limited stability after 6 wk. Unloaded HYADD3 and HYADD4 controls could not be identified at the time of explantation. Histology of HYADD3 revealed islets of mature adipocytes and vessels embedded in fat tissue surrounded by gel. In contrast, no fat formation was found in HYADD4 gels when implanted in the ear.

CONCLUSIONS

Histological findings demonstrate that HYADD3 is a promising gel for generating adipose tissue. Even though HYADD3 might be a potential material for the reconstruction of small tissue defects, the question remains as to whether the adipose tissue within the gel is attributable to preadipocyte maturation or ingrowth from neighboring tissue.