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

An Evaluation of Autologous Fat Injection as a Treatment for Velopharyngeal Insufficiency: A Review and Integrated Data Analysis

BACKGROUND

Velopharyngeal insufficiency (VPI) is a condition characterized by incomplete separation of the oral and nasal cavities during speech production, thereby leading to speech abnormalities and audible nasal emissions. Subsequently, this adversely impacts communication and potentially interpersonal social interactions. Autologous fat grafting (AFG) to the velopharynx, a minimally invasive technique, aims to improve oronasal separation by providing bulk and advancing the posterior pharyngeal wall toward the soft palate. Despite its potential, the relative novelty of AFG in treating VPI has resulted in reporting of inconsistent indications, varied surgical techniques, and mixed outcomes across existing literature.

METHODS

This systemic review examined the evidence of AFG for VPI treatment over the past decade (2013-2023). A thorough search across five electronic databases yielded 233 studies, with 20 meeting the inclusion criteria (e.g., utilized fat injection as their selected VPI treatment, conducted study in human subjects, did not perform additional surgical procedure at time of fat injection). Selected studies encompassed patient and surgical intervention characteristics, perceptual speech assessment (PSA) scores, gap sizes, nasalance measurements, and complications.

RESULTS

The majority of patients had a prior cleft palate diagnosis (78.2%), in which nasoendoscopy was the prevalent method for visualizing the velopharyngeal port defect. Fat harvesting predominantly occurred from the abdomen (64.3%), with an average injection volume of 6.3 mL across studies. PSA and subjective gap size scores were consistently higher preoperatively than postoperatively. PSA score analysis from seven studies revealed significant and sustained improvements postoperatively. Gap size score analysis from four studies demonstrated similar preoperative and postoperative differences. Complications were reported in 17 studies, yielding a 2.7% summative complication rate among 594 cases.

CONCLUSIONS

Autologous fat grafting has emerged as a minimally invasive, safe, and effective treatment for mild to moderate VPI. However, challenges remain because of variability in patient selection criteria, diagnostic modalities, and outcome measurements. This review underscores the need for randomized control trials to directly compare AFG with standard-of-care surgical interventions, providing more conclusive evidence of its clinical efficacy.

Transplantation of Cold-Stimulated Subcutaneous Adipose Tissue Improves Fat Retention and Recipient Metabolism

BACKGROUND

Induction of beige fat for grafting is an emerging transplantation strategy. However, safety concerns associated with pharmaceutical interventions limit its wider application. Moreover, because beige fat is a special type of fat with strong metabolic functions, its effect on the metabolism of recipients after grafting has not been explored in the plastic surgery domain.

OBJECTIVES

The aim of this study was to explore whether cold-induced inguinal white adipose tissue (iWAT) transplantation has a higher retention rate and beneficial effects on recipient metabolism.

METHODS

C57/BL6 mice were subjected to cold stimulation for 48 hours to induce the browning of iWAT and harvested immediately. Subsequently, each mouse received a transplant of 0.2 mL cold-induced iWAT or normal iWAT. Fat grafts and recipients' iWAT, epididymal adipose tissue, and brown adipose tissue were harvested at 8 weeks after operation. Immunofluorescence staining, real-time polymerase chain reaction, and western blot were used for histological and molecular analysis.

RESULTS

Cold-induced iWAT grafting had a higher mean [standard error of the mean] retention rate (67.33% [1.74%] vs 55.83% [2.94%], P < .01) and more satisfactory structural integrity than normal iWAT. Histological changes identified improved adipose tissue homeostasis after cold challenge, including abundant smaller adipocytes, higher levels of adipogenesis, angiogenesis, and proliferation, but lower levels of fibrosis. More importantly, cold-induced iWAT grafting suppressed the inflammation of epididymal adipose tissue caused by conventional fat grafting, and activated the glucose metabolism and thermogenic activity of recipients' adipose tissues.

CONCLUSIONS

Cold-induced iWAT grafting is an effective nonpharmacological intervention strategy to improve the retention rate and homeostasis of grafts. Furthermore, it improves the adverse effects caused by traditional fat grafting, while also conferring metabolic benefits.

Recent advances in the use of extracellular vesicles from adipose-derived stem cells for regenerative medical therapeutics

Adipose-derived stem cells (ADSCs) are a subset of mesenchymal stem cells (MSCs) isolated from adipose tissue. They possess remarkable properties, including multipotency, self-renewal, and easy clinical availability. ADSCs are also capable of promoting tissue regeneration through the secretion of various cytokines, factors, and extracellular vesicles (EVs). ADSC-derived EVs (ADSC-EVs) act as intercellular signaling mediators that encapsulate a range of biomolecules. These EVs have been found to mediate the therapeutic activities of donor cells by promoting the proliferation and migration of effector cells, facilitating angiogenesis, modulating immunity, and performing other specific functions in different tissues. Compared to the donor cells themselves, ADSC-EVs offer advantages such as fewer safety concerns and more convenient transportation and storage for clinical application. As a result, these EVs have received significant attention as cell-free therapeutic agents with potential future application in regenerative medicine. In this review, we focus on recent research progress regarding regenerative medical use of ADSC-EVs across various medical conditions, including wound healing, chronic limb ischemia, angiogenesis, myocardial infarction, diabetic nephropathy, fat graft survival, bone regeneration, cartilage regeneration, tendinopathy and tendon healing, peripheral nerve regeneration, and acute lung injury, among others. We also discuss the underlying mechanisms responsible for inducing these therapeutic effects. We believe that deciphering the biological properties, therapeutic effects, and underlying mechanisms associated with ADSC-EVs will provide a foundation for developing a novel therapeutic approach in regenerative medicine.

Histological Properties of Adipose Tissue as an Autologous Tissue Filler Harvested from Different Donor Areas and Impact of Centrifugation

Background

As a burgeoning technique in reconstructive and aesthetic surgery, lipofilling's success is hindered by the unpredictability of graft integrity and quality. This study addresses the critical need to enhance consistency and reproducibility by exploring the clinical utility of adipose tissue from specific body areas, considering the influence of patient-specific factors and mechanical processing on fat graft integrity and morphology.

Methods

In a prospective, randomized, single-blind study, 52 patients undergoing surgical reconstruction due to significant deformities were enrolled. Lipoaspiration from four areas was performed. Adipose tissue was compared using five parameters of tissue damage and 10 parameters of graft integrity, assessed immediately postcollection and after centrifugation. The study aimed to evaluate the structural integrity and clinical applicability of adipocytes.

Results

Morphological assessment revealed no significant differences in adipose tissue quality across donor sites, suggesting consistent graft quality regardless of the harvesting location. Centrifugation induced more morphological damage than noncentrifuged samples, but the overall graft integrity was maintained due to increased cell density. Higher graft acceptance parameters were noted in noncentrifuged samples compared with centrifuged ones.

Conclusions

Despite centrifugation-induced morphological changes, adipose tissue integrity remains relatively unaffected, supporting a flexible approach to donor site selection. The consistent quality of adipose tissue underscores the potential for autologous fat transplantation across various clinical scenarios. Optimizing graft processing techniques is crucial for enhancing the predictability and efficacy of lipofilling.

Combining High-Density Fat and Condensed Low-Density Fat Injections for Precise Facial Rejuvenation

BACKGROUND

Facial aging involves ptosis, adipose atrophy, and skeletal resorption. Depletion of adipose tissue primarily affects the deep facial fat compartment, leading to facial depression or ptosis, accompanied by atrophy of the superficial compartment. Restoring volume in the deep fat compartment is crucial for facial rejuvenation, while enhancing its supportive properties is also important. The superficial fat compartment contains small-sized adipocytes, and autologous fat grafting is a popular approach. However, variability in fat retention, homogeneity, and processing methods can impact outcomes, necessitating careful selection of a suitable fat processing material for precise facial fat grafting.

METHOD

A retrospective study was conducted on 50 patients who underwent facial augmentation using combined transplantation of high-density fat (HDF) and condensed low-density fat (CLDF) and 25 patients who underwent conventional Coleman fat grafting. Coleman fat was harvested by standard technique and the adipose tissue was divided into HDF and CLDF fractions through centrifugation. Subsequently, the low-density fat fraction was subjected to a process involving physical disruption followed by additional centrifugation to obtain CLDF. The CLDF fraction was consequently injected into the pre-SMAS subcutaneous layer of the superficial fat compartments. Patient satisfaction was evaluated using a typical Likert scale. Photographs were taken and imageological examinations were performed before and after treatment.

RESULT

The CLDF+HDF grafting group demonstrated a significantly shorter duration of swelling (6.0 ± 1.2 to 12.6 ± 3.3 days) and higher level of patient satisfaction when compared to the Coleman fat group. No serious complications were observed among all the patients who received the injections.

CONCLUSION

The use of this new treatment approach allows for precise fat transplantation in facial regions. The use of high-concentration fat filling for deep facial layers and CLDF filling for superficial layers is a safe and effective treatment plan for facial rejuvenation.

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 .

Increased Total Antioxidant Capacity Value Improves Survival of Fat Grafts in Rat Model

BACKGROUND

Although studies aiming to increase fat graft survival continue, in this study, the authors aimed to investigate the effects of different antioxidants on total antioxidant capacity (TAC) and their effect on graft survival.

METHODS

Thirty-two male Wistar rats were divided into four equally sized groups, including a control group and three antioxidant groups receiving either melatonin (10 mg/kg), zinc (2 mg/kg), or vitamins E and C (100 mg/kg). Autologous fat grafts (1.7 ± 0.4 g) were transferred to the dorsal subcutaneous region, and total antioxidant capacity was measured on days 0 and 1, week 1, and monthly until the third month. Transferred graft volume and mass (1.3 ± 0.4 g) were measured using the liquid overflow method and precision scales at the end of the study. Routine hematoxylin and eosin staining and immunohistochemistry against perilipin were performed for semiqualitative analysis and H-score for viable adipose cells, respectively.

RESULTS

Collected fat grafts measured significantly less in weight and volume and the survival rate was lower in the control group ( P < 0.01). The control group exhibited a reduction in TAC, whereas all groups receiving antioxidants had an increase in TAC during the first week ( P = 0.02, P = 0.008, and P = 0.004 for melatonin, zinc, and vitamins, respectively). Immunohistochemistry of the antioxidant group demonstrated a statistically significant excess and reactivity of cells staining with perilipin antibodies.

CONCLUSION

In this animal study, the beneficial effect of antioxidants on fat graft survival can be related to the significant increase in TAC following the first week of their administration.

CLINICAL RELEVANCE STATEMENT

Antioxidants improve fat graft survival and quality in this rat model, by increasing total antioxidant capacity in the first week of administration.

Mid-term evaluation of the surgical management of patulous Eustachian tube dysfunction: a STROBE observational study

INTRODUCTION

Patulous Eustachian tube (PET) is a condition affecting approximately 0.3% to 6.6% of the population, with autophony being the predominant complain. The management of PET lacks a well-defined standard in the literature as no effective medical treatments have been documented but various surgical options are available. This study aims to report mid-term outcomes following surgical management of PET.

MATERIALS AND METHODS

All patients who underwent surgical intervention for PET between September 2017 and June 2022 were enrolled. Data encompassing general demographics, quality of life (GBI), and procedure-specific data were collected.

RESULTS

A total of 30 PET cases (in 19 patients) underwent surgical intervention including 9 injections of hyaluronic acid, 13 fat injections, 6 endoscopic shim insertions, 1 cartilage graft, and 1 injection of hydroxy apatite. After an average follow-up of 22 ± 14 months, 16 cases (53%) achieved complete symptom relief, while 8 cases (26.6%) reported partial relief. Additionally, 11(36%) cases required multiple surgeries. No specific surgical technique demonstrated superiority. Quality of life improved in 77% of cases based on 10 out of 13 GBI collected. Recurrence of PET symptoms occurred on average 10.6 ± 9.7 months after initial surgery, with an estimated global risk of 75% at 3 years. Transient serous otitis media was observed in only 4 cases (13.3%).

CONCLUSION

Surgical intervention for PET was found to be effective, achieving complete symptom relief in 53% of cases and significantly improving quality of life 2 years post-surgery. However, a substantial portion of cases necessitated one or more re-interventions. The durability of effectiveness appears to diminish over time.

Endoscopic mastectomy followed by immediate breast reconstruction with fat grafting for breast cancer

BACKGROUND

Although endoscopic mastectomy has been associated with good tolerance and enhanced patient satisfaction, limitations such as the implant or flap size for reconstruction with small incisions remain unresolved. Fat grafting (FG) can expand tissue volume with pinhole skin incisions. Herein, we evaluated the safety and efficacy of endoscopic mastectomy followed by immediate FG.

METHODS

Patients who underwent endoscopic mastectomy with immediate FG reconstruction from 2015 to 2021 were retrospectively evaluated to establish surgical outcomes and prognosis.

RESULTS

Twenty-three patients with clinical stage 0 or I breast cancer underwent unilateral endoscopic mastectomy with immediate FG. The median age was 45 years (41-55), and the median body mass index was 19.3 kg/m2 (15.8-26.6). Endoscopically performed procedures included skin-sparing mastectomies in 18 patients (78%) and nipple-sparing mastectomies in five patients (22%). The median procedure duration was 295 min (242-346). The median specimen weight was 133 g (71-334), and the median grafted fat volume was 200 mL (136-320). No patient required reoperation or additional procedures for complications. One patient experienced recurrence at a median follow-up of 56.1 months and underwent resection; the patient was alive without recurrence 54 months post-resection.

CONCLUSION

To the best of our knowledge, this is the first report of endoscopic mastectomy with immediate FG for reconstruction. When compared with other immediate autologous reconstructions, our strategy could minimize the skin incision and procedure duration, as well as limit complications. Further prospective investigations are needed to evaluate oncological safety, surgical outcomes, and patient satisfaction.

PPAR-γ regulates the polarization of M2 macrophages to improve the microenvironment for autologous fat grafting

The unpredictable survival rate of autologous fat grafting (AFG) seriously affects its clinical application. Improving the survival rate of AFG has become an unresolved issue in plastic surgery. Peroxisome proliferator-activated receptor-γ (PPAR-γ) regulates the adipogenic differentiation of adipocytes, but the functional mechanism in AFG remains unclear. In this study, we established an animal model of AFG and demonstrated the superior therapeutic effect of PPAR-γ regulation in the process of AFG. From day 3 after fat grafting, the PPAR-γ agonist rosiglitazone group consistently showed better adipose integrity, fewer oil cysts, and fibrosis. Massive macrophage infiltration was observed after 7 days. At the same time, M2 macrophages begin to appear. At day 14, M2 macrophages gradually became the dominant cell population, which suppressed inflammation and promoted revascularization and fat regeneration. In addition, transcriptome sequencing showed that the differentially expressed genes in the Rosiglitazone group were associated with the pathways of adipose regeneration, differentiation, and angiogenesis; these results provide new ideas for clinical treatment.

Are We Speaking the Same Language? A Systematic Review on the Use of Consistent Language in Reporting Fat Necrosis in Autologous Fat Grafting of the Breast

BACKGROUND

Autologous fat grafting is a widely adopted approach to optimize outcomes in breast reconstruction and augmentation. Although fat necrosis is a well-known consequence of autologous fat grafting, it remains inconsistently defined in the literature. In late 2014, the Food and Drug Administration released a draft guidance to restrict future autologous fat grafting-a statement that was permissively modified in late 2017. In the context of evolving guidelines and autologous fat grafting outcome data, the language and descriptions of fat necrosis are inconsistent in the literature.

METHODS

Five databases were queried for studies reporting fat necrosis following autologous fat grafting for breast reconstruction or augmentation from inception to August 11, 2022. Studies were temporally stratified according to released FDA guidelines: pre-2015, 2015-2017, and 2018-2022.

RESULTS

Sixty-one articles met inclusion criteria. Prior to 2015, 6 of 21 studies (28.6%) offered clear definitions of fat necrosis. In contrast, the 2015-2017 period demonstrated an absence of clear fat necrosis definitions (0/13 studies, p = 0.03). Though the 2018-2022 period exhibited a rise in annual publications compared with the pre-2015 period (5.4 vs. 1.9, respectively, p = 0.04), this was not matched by a rise in clear fat necrosis reporting (14.8% studies, p = 0.45). Across all periods, only 16.4% of articles offered clear definitions, which exhibited wide heterogeneity.

CONCLUSION

Despite the increasing popularity of autologous fat grafting, fat necrosis remains inconsistently defined and described, especially in the context of changing FDA guidelines. This limits the reliable interpretation and application of the current literature reporting fat necrosis outcomes.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Autologous fat grafting and adipose-derived stem cells therapy for acute burns and burn-related scar: A systematic review

Objectives

The objective of this study was to analyze all available research on the application of autologous fat grafting (AFG) and adipose-derived stem cells (ADSC) to present evidence-based recommendations, particularly in the clinical treatment of acute burns and burn-related scars.

Materials and Methods

We conducted a systematic search of PubMed, COCHRANE, and EMBASE, as well as a manual search of previous reviews' reference lists up. The risk of bias (RoB) was assessed using RoB 2.0 and ROBINS-I, where appropriate.

Results

Six eligible studies were selected (2 randomized clinical trials [RCT], 1 retrospective cohort, and 3 experimental studies) with subjects ranging from 3 to 100. Only one study evaluated the use of AFG for acute burns. Improvements in wound healing, vascularization, scar characteristics, and tissue architecture were generally observed in some studies, supported by molecular markers, while one study reported nonsignificant results. Subjective patient satisfaction was reported to have improved. Functional outcomes improvement in the treated regions was minimal. However, study heterogeneity arose mainly from treatment protocols. Cautious results interpretation due to potential bias, especially in selection and confounding domains, and limited clinical trials are important to note. More studies are needed to evaluate.

Conclusion

AFG and ADSC hold potential as valuable treatment options for burn-related scars, supported by a body of evidence, but further well-designed RCT are needed. The efficacy of acute burn settings is yet to be further evaluated since evidence is limited.

CT volumetry study of microfat graft survival from different donor sites in augmenting the enophthalmic socket

PURPOSE

To evaluate autologous fat grafts harvested from the abdomen versus the thigh for treating the enophthalmic socket using CT volumetry.

METHODS

A randomized prospective interventional study including 20 patients suffering from unilateral enophthalmic socket. Pre-operative clinical assessment included photographs, exophthalmometry reading as well as CT volumetry for volume deficit calculations and the harvesting site was randomly allocated (abdomen or thigh). All patients completed 6 months of follow-up. Exophthalmometry change and percentage of retained fat with the globe included and without it at follow-up were measured.

RESULTS

Microfat graft survival showed no statistically significant correlation with sex, age, or donor site. Mean percentage of retained fat with globe and without it were 14.75% and 25.31%, respectively. Difficulty of extraction and degree of volume deficit correlated significantly with percentage of fat retained. Exophthalmometer change correlated significantly with percentage of fat retained.

CONCLUSION

Autologous fat grafting is a safe and effective technique for volume augmentation of enophthalmic sockets regardless of its harvesting site. CT volumetry has an important role in accurately measuring the volume deficit as well as the postoperative results.

Superficial Intramuscular Gluteal Lipograft by Doppler Ultrasound: A Report of 24 Patients

Background

Gluteal fat grafting is a common procedure in liposculpture. This study proposes a Doppler ultrasound-guided intramuscular and subcutaneous gluteal lipotransfer technique that allows for visualization of the location of the gluteal vessels, avoiding approaching them during lipotransfer by having the cannula localized during fat infiltration.

Methods

This new technique was applied to 24 women after obtaining informed consent and providing them with a clear explanation of potential risks and complications. Doppler ultrasound was used to locate the site and depth of blood vessels, and for quadrant scanning of vessels and superficial intramuscular visualization of the cannula's location. Intramuscular lipotransfer was performed with a volume of 400 mL per gluteus (or less), and 12 patients underwent magnetic resonance imaging before and 3 months after surgery.

Results

This technique allowed for visualizing the location of the gluteal vessels, and infiltration could be easily performed in patients. In the 24 glutei reviewed postsurgery, from 12 patients who underwent pre- and postsurgery magnetic resonance imaging, intramuscular fat was found; however, there was no migration outside the gluteus maximus muscle.

Conclusions

No local or systemic complications were observed. The results of our report show that fat filtration did not migrate outside the gluteus maximus muscle. This finding seeks to promote new research to create theoretical/practical precedents for the intervention of plastic surgeons and, from there, promote the standardization of a new and safe technique.

Adipose Component Transplantation: An Advanced Fat-Grafting Strategy for Facial Rejuvenation

BACKGROUND

Autologous fat grafting is frequently used for volume augmentation and tissue regeneration. The uniform physical and biological characteristics of fat grafts, however, limit their optimal effects in various situations. Subjecting fat tissue to different mechanical processes results in adipose-derived products with distinct biological components and physical features. The present study describes a novel facial fat-grafting strategy, adipose component transplantation (ACT), that yields different adipose products that can be applied to specific injection sites.

METHODS

All patients who underwent ACT were evaluated retrospectively. Fat tissue samples were fractionated into high-density fat, adipose matrix complex, stromal vascular fraction gel, and adipose collagen fragment, as described. Each of these fractions was processed and injected into indicated recipient sites. Additional SVF gel was cryopreserved and, if necessary, injected during the following 3 months. Patients were followed up after 1, 2, 3, and 6 months, and annually thereafter.

RESULTS

From March of 2020 to September of 2021, 78 patients underwent whole face fat grafting using the ACT strategy. All operations and secondary injections of cryopreserved SVF gel were uneventful. There were no major complications, and final aesthetic results were satisfactory in 91% of patients.

CONCLUSIONS

The ACT strategy allows specific adipose products to be applied to specific injection sites, as warranted. Adipose matrix complex is indicated for sufficient rigid support, high-density fat when large volumes are required, SVF gel for precise injection and cryopreservation, and ACF as mesotherapy for skin rejuvenation. The ACT strategy optimizes the biological functions and physical features of different adipose-derived products.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Toward facial rejuvenation; A clinical trial to assess the efficacy of nano fat grafting on wrinkles

INTRODUCTION

With increasing age, patients' facial volume decrease. For this reason, nano fat grafting has recently gained popularity as adjunctive treatment to facial rejuvenation procedures. However, few quantitative studies have been conducted to investigate the impact of nano fat on facial wrinkles.

AIMS

In the present study, authors aim to investigate the therapeutic effect of intradermal injection of nano fat on fine facial wrinkles and assess their changes over 7 months of follow-up.

METHODS

In this randomized trial, 15 patients with fine facial wrinkles were enrolled. The fat was harvested from the abdomen and processed into nano fat. Nano fat was injected into the facial wrinkles intradermally with a needle of 27 gauge. The patients were evaluated before and 7 months postinjection utilizing Visio face 1000D (CK electronic, manufactured in Germany); and four parameters of wrinkles (area, volume, depth, and percent area) were evaluated before and after the nano fat injection.

RESULTS

Our evaluation with Visio face showed that nano fat injection was significantly reduced the volume, area, depth, and percent area of wrinkles after 7 months of follow-up without serious long-lasting adverse effects. Moreover, wrinkles with higher percent area, depth and volume loss show greater improvement after the treatment. Our results also indicate that males and females equally benefit from this treatment except for the percent area parameter that was improved more significantly in male patients.

CONCLUSION

Our study showed that intradermal injection of nano fat significantly decreases the volume, area, depth, and percent area of fine facial wrinkles. Further quantitative studies with control groups and larger sample sizes are required.

Single-Step Full-Face Surgical Treatment of the Facial Profile

The present study was performed to describe how much affordable, feasible, and straightforward is the approach the authors called "single-stage full-face surgical profileplasty," tailored to greatly improve the surgery of the facial profiling setting and achieve complete profile correction at the same time. From January 2010 to May 2019, 113 patients (95 females and 18 males; aged 19 - 63 years) were surgically treated for full-face profile amelioration. Profile correction was performed by using a combination of five procedures out of other various previously experienced: forehead fat grafting, rhinoplasty, lip fat grafting, genioplasty, and submental liposuction. All patients were assessed at 1, 3, 6, and 12 months following surgery for assessing the surgical profile treatment (SPT) outcome and any possible side effects of the combined treatment. Facial profile stability at 1 year was taken as the completion point of this treatment. Arnett et al's "Soft Tissue Cephalometric Analysis" (1999) was used to clinically evaluate the soft tissues before and after the SPT. Patients' satisfaction was measured with the Client Satisfaction Questionnaire-8" at 3 and 12 months after surgery. Statistics were used for Arnett et al's evaluation. Almost all the values were consistent and reached the normal ranges indicated by Arnett et al (p < 0.001), confirming that the desired results of the surgical profileplasty have been achieved. Single-stage full-face surgical profile treatment helps in correcting faults of the global facial deformity, in every single treated area, providing an overall improvement in facial aesthetics and harmony. Obtaining the simultaneous correction in the whole face has also the advantage of avoiding multiple surgical procedures, reducing postoperative discomfort, and the overall risks for the patient due to multiple surgical and anesthetic procedures.

Tissue engineering strategies for breast reconstruction: a literature review of current advances and future directions

Background and Objective

Mastectomy is a primary treatment for breast cancer patients, and both autologous and implant-based reconstructive techniques have shown excellent results. In recent years, advancements in bioengineering have led to a proliferation of innovative approaches to breast reconstruction. This article comprehensively explores the promising perspectives offered by bioengineering and tissue engineering in the field of breast reconstruction.

Methods

A literature review was conducted between April and June 2023 on PubMed and Google Scholar Databases. All English and French articles related to bioengineering applied to the field of breast reconstruction were included. We used the Evidence-Based Veterinary Medicine Association (EBVM) Toolkit 14 checklist for narrative reviews as a quality assurance measure and the Scale for the Assessment of Narrative Review Articles (SANRA) tool to self-assess our methodology.

Key Content and Findings

Over 130 references related to breast bioengineering were included. The analysis revealed four key applications: enhancing the quality of the skin envelope, improving the viability of fat grafting, creating breast shape and volume via bio-printing, and optimizing nipple reconstruction through engineering techniques. The primary identified approaches revolved around establishing structural support and enhancing cellular viability. Structural techniques predominantly involved the implementation of 3D printed, decellularized, or biocompatible material scaffolds. Meanwhile, promoting cellular content trophicity primarily focused on harnessing the regenerative potential of adipose-derived stem cells (ADSCs) and increasing the tissue's survivability and cell trophicity.

Conclusions

Tissue and bioengineering hold immense promise in the field of breast reconstruction, offering a diverse array of approaches. By combining existing techniques with novel advancements, they have the potential to significantly enhance the therapeutic options available to plastic and reconstructive surgeons.

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

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

Technical Precision with Autologous Fat Grafting for Facial Rejuvenation: A Review of the Evolving Science

SUMMARY

The scientific study of facial aging has transformed modern facial rejuvenation. As people age, fat loss in specific fat compartments is a major contributor to structural aging of the face. Autologous fat grafting is safe, abundant, readily available, and completely biocompatible, which makes it the preferred soft-tissue filler in the correction of facial atrophy. The addition of volume through fat grafting gives an aging face a more youthful, healthy, and aesthetic appearance. Harvesting and preparation with different cannula sizes and filter-cartridge techniques have allowed for fat grafts to be divided based on parcel size and cell type into three major subtypes: macrofat, microfat, and nanofat. Macrofat and microfat have the benefit of providing volume to restore areas of facial deflation and atrophy in addition to improving skin quality; nanofat has been shown to improve skin texture and pigmentation. In this article, the authors discuss the current opinions regarding fat grafting and how the evolving science of fat grafting has led to the clinical utility of each type of fat to optimize facial rejuvenation. The opportunity exists to individualize the use of autologous fat grafting with the various subtypes of fat for the targeted correction of aging in different anatomic areas of the face. Fat grafting has become a powerful tool that has revolutionized facial rejuvenation, and developing precise, individualized plans for autologous fat grafting for each patient is an important advancement in the evolution of facial rejuvenation.

Quantitative Assessment of Periocular Autologous Fat Transfer Survival Using 3D Stereophotogrammetric Imaging

PURPOSE

To assess periocular autologous fat transfer (AFT) survival by assessment of volume change with sequential 3D VECTRA imaging.

OBJECTIVE

Little is known about the patterns of graft survival of AFT in the periorbital region, especially in cases involving prior radiotherapy or trauma. The aim of this pilot study was to characterize fat survival following AFT in patients with a broad range of clinical indications, with and without a history of prior radiotherapy, for both periocular and orbital AFT, and in a subgroup of patients with an anophthalmic socket.

METHOD

A single-institution, prospective cohort study involving 18 applications of AFT for volume augmentation in the periocular and orbital area. All patients had sequential 3D VECTRA photographs following a validated standardized protocol. Patient demographics, including gender, age, ethnicity, underlying diagnosis, and volume of fat injected, were also collected.

RESULTS

In total 13 patients were enrolled, 9 female (69.2%) and 4 male (31.0%). Mean age at the time of surgery was 47.8 years. Patients had volume deficiency secondary to a variety of causes; the most common cause was postenucleation socket syndrome following trauma in 6 patients (46.2%). The mean fat survival volume at the 1-month postoperative point was 70% and 55% by 6 months. AFT conducted with a multiport cannula for fat harvesting use had an initial higher rate of fat reabsorption with ANOVA p = 0.002, however, this was not observed at the later follow-up periods. There was no statistically significant difference in fat survival between abdominal or thigh donor fat sites. There was no statistically significant difference in residual injected volume at the early follow-up period between patients who had prior radiotherapy and those who did not p = 0.8496.

CONCLUSION

AFT is an effective treatment for periorbital volume compromise with an acceptable survival rate in all categories of patients. Complex etiologies such as radiotherapy-related orbital and midface dysgenesis should not be a contraindication for AFT, with no difference in outcomes.

Delivery of microRNA-423-5p by exosome from adipose-derived stem/stromal cells inhibits DVL3 to potentiate autologous fat graft survival through adipogenesis and inflammatory response

Autologous fat grafting represents a reconstructive technique but is limited by unstable graft retention. Based on existing reports and bioinformatics prediction, we hypothesized that delivering exosomes from human adipose-derived stem/stromal cells (hADSC-Exo) would increase fat graft survival and further explore the mechanism. hADSC-Exo were extracted and identified. An autologous fat grafting model was established using donor and recipient mice, followed by hADSC-Exo treatment. hADSC-Exo promoted the retention of autologous fat grafts in mice, along with increased adipocyte activity, angiogenesis, and decreased inflammation in grafts. Moreover, hADSC-Exo potentiated the adipose differentiation of 3T3-L1 cells, enhanced the angiogenic and migratory capacity of human umbilical vein endothelial cells, and inhibited the inflammation and viability of RAW 264.7 cells. The therapeutic effect of hADSC-Exo on fat grafting was associated with the delivery of microRNA (miR)-423-5p. Deletion of miR-423-5p in Exo impaired the function of hADSC-Exo on fat retention. miR-423-5p bound to DVL3 to suppress DVL3 expression, and DVL3 deletion promoted adipose differentiation of 3T3-L1 cells. In conclusion, our findings further widen the theoretical basis of the clinical application of hADSC-Exo in autologous fat grafts.

Emerging Approaches to Augmentation Mastopexy in the Nontraditional Weight-Loss Patient

An aesthetic result of the breast for a body contouring patient is approached from a reconstructive standpoint rather than a cosmetic one. Attenuation of the supportive ligaments, a damaged soft tissue envelope, and generalized laxity of the torso, all contribute to one of the most complex problems in body contouring. The marriage of the reconstructive approach to the breast, advanced soft tissue maneuvers, and new technologies allow for unprecedented results. This chapter presents emerging approaches for supported volumization of the breast through techniques such as breast cerclage suspension, subfascial augmentation, composite augmentation with fat grafting, and additive mesh support.

A Multicenter Pilot Study of a Novel Allograft Adipose Matrix in Malar and Prejowl Volume Restoration

Background

Allograft adipose matrix (AAM) offers a novel, off-the-shelf, and readily available natural option in the treatment of facial soft tissue volume and reconstructive deficits. AAM is a natural soft tissue supplement or replacement that can support cushioning and volume correction. A prospective multicenter pilot study evaluated AAM in facial volume restoration.

Methods

Eleven women (mean age of 55.8 ± 10.9 y) with midface volume deficit were followed up for 24 weeks after AAM treatment in this institutional review board-approved multicenter pilot study. The clinical safety and efficacy of the AAM treatment were evaluated using clinical scales and three-dimensional quantitative facial photography.

Results

AAM was safe to address facial volume deficits, with minor site-related adverse events and discomfort that resolved within 2-4 weeks. Observations also revealed facial volume improvements throughout the study with 91% positive responders. At week 24, the subject facial satisfaction scores revealed an 86% increase compared to baseline, along with a statistically significantly improved midface fullness compared to baseline.

Conclusion

AAM offers a natural and safe option for midface volume restoration and supports overall satisfaction and volume improvements.

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 .

Autologous Fat Grafting Is Not Superior to Placebo as Treatment of Postherpetic Neuralgia: A Double-Blind Randomized Clinical Trial

BACKGROUND

Postherpetic neuralgia (PHN) is a chronic pain syndrome occurring after a herpes zoster outbreak. While there is no effective treatment available today, autologous fat grafting has shown promise. This randomized controlled trial investigated the effectiveness of fat grafting as treatment for PHN compared with a sham treatment.

METHODS

A total of 46 participants with PHN were included. After liposuction under general anesthesia, participants were randomly assigned to receive either autologous fat grafting or saline injection to the area of pain. The primary outcomes were the average and maximum degree of pain measured on an 11-point numeric rating scale. Secondary outcomes were quality and degree of neuropathic pain (Neuropathic Pain Symptom Inventory) and quality of life (36-Item Short-Form Health Survey).

RESULTS

Forty-two participants completed follow-up of 6 months. For maximal degree of pain, a reduction of -1.1 ± 0.6 and -1.0 ± 0.5 mean change (±SE) on the numeric rating scale was observed in the intervention and control groups, respectively. For average degree of pain, the reduction was -1.2 ± 0.5 and -1.3 ± 0.4 in the intervention and control groups, respectively. The authors did not observe any significant changes in the neuropathic pain and quality-of-life parameters. For all measured outcomes, the differences between the groups were not statistically significant.

CONCLUSIONS

The authors did not find autologous fat grafting superior to a placebo when treating PHN of the skin. Given their results, they cannot recommend the routine use of this method to treat these pains.

CLINICAL RELEVANCE STATEMENT

Since autologous fat grafting was not proven to be more effective than a placebo in treating PHN, alternative treatment options should be explored. It is also essential to emphasize the importance of prophylactic vaccination against herpes zoster.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, I.

Fat transplant: Amazing growth and regeneration of cells and rebirth with the miracle of fat cells

BACKGROUNDS AND OBJECTIVE

During fat transplantation, adipose tissue is removed from the body and injected into different areas under the skin. The goal of this review article is to look into the efficacy and applicability of fat transplantation in regenerative medicine and rejuvenation, including Nanofat, Microfat, and Millifat.

METHODS

As a search strategy and study selection, we searched the PubMed and Medline databases until 2023 using related keywords (e.g., Nanofat, Microfat and Millifat, Regenerative Medicine, and Rejuvenation).

RESULTS

Autologous fat transplantation has no risk of an allergic reaction or rejection of the transplant by the individual. Autologous adipose tissue is considered an ideal filler for facial rejuvenation and is suggested as the most biocompatible and non-immunogenic skin filler. Adipose tissue transplant may have semi-permanent to permanent effects. According to recent reports, adipose tissues possess a high percentage of mature stem cells. The effect of regenerating adipose tissue and its intrinsic cells can be described as an obvious process. Variations in the sizes of adipose tissues can result in different results depending on the surgical site. Based on topographic assessment, graft fats are assigned depending on the anatomical locations and the size such as Millifat (2-2.5 mm), Microfat (1 mm), and Nanofat (500 μm or less).

CONCLUSION

Some characteristics of fat tissue increase its effectiveness, such as increasing stem cells, growth factors, cytokines, and compounds effective in repair, regeneration, and rejuvenation.

Evolution of the Push-2-Spin Fat Graft Processing Device: Enhancing Efficiency and Reducing Risk of Contamination

Background

Small-volume fat graft efficiency is a critical determinant of the cost and material effectiveness of aesthetic fat grafting in the clinical space. Recent development of devices, such as the Push-2-Spin (P2S) system (Pittsburgh, PA), has improved upon the process by yielding a rapid, handheld, multi-use system to minimize operative time and mess.

Objectives

In this study, the authors describe further technical innovations on the P2S prototype that improve operative ease of use, time, and safety.

Methods

Abdominoplasty samples were obtained as discarded tissue. Lipoaspirate was collected utilizing a 3.0 mm liposuction cannula and processed through centrifugation (Coleman technique), gauze (telfa) rolling, mesh straining, the tabletop P2S device (prototype), or the P2S handheld (P2S-H) device. Operative processing time, spin time, oil fraction, stromal vascular fraction (SVF) yield and viability, and adipocyte viability were assessed to compare the efficacy and viability of each device/technique. Blood agar smears of lipoaspirate were performed to assess for risk of contamination.

Results

The P2S-H device outperformed its prior iteration in rotary and processing speed and was significantly faster than each other technique assessed. Furthermore, the use of an inline system offered significant advantages over open-air techniques in terms of resistance to contamination. Serial use characteristics were assessed; under these conditions, oil yield as well as adipocyte and SVF number and viability was similar between all techniques.

Conclusions

The technical advancements to the P2S system which enable single-unit, handheld operation significantly improve operative time and minimize space requirements. This operative quality of life improvement comes at no cost to the efficacy of oil extraction, cellular yield, or cell viability.

Level of Evidence 3

Extracellular Vesicles Derived From Hypoxia-Treated Human Adipose Stem Cells Increase Proliferation and Angiogenic Differentiation in Human Adipose Stem Cells

BACKGROUND

Adipose-derived stem cells (ADSCs) are crucial in cell-assisted lipotransfer (CAL). ADSC-derived exosomes could improve the survival of CAL. Almost all relevant research now ignores ADSCs in favor of studying the proangiogenic potential of extracellular vesicles (EVs) on human umbilical vein endothelial cells (HUVECs).

OBJECTIVES

Given the significance of ADSCs in CAL, the authors sought to verify that EVs from ADSCs under hypoxia treatment can enhance the angiogenic potential of ADSCs.

METHODS

EVs were harvested from human ADSCs (hADSCs) under normoxia and hypoxia. A Cell Counting Kit-8 (CCK-8) assay was used to measure the proliferation of hADSCs. By examining the expression of CD31, vascular endothelial growth factor receptor 2, and vascular endothelial growth factor, the pro-angiogenic differentiation potential was assessed. Moreover, a tube formation experiment was carried out to evaluate the pro-angiogenic differentiation potential.

RESULTS

Hypoxic EVs showed more significant pro-proliferative and pro-angiogenic potential. Angiogenesis was more vigorous in hADSCs treated with hypoxic EVs than in those treated with nomorxic EVs. The hADSCs treated with hypoxic EVs expressed higher angiogenic markers, according to real-time polymerase chain reaction (RT-PCR) and Western blot analysis, which revealed more angiogenic marker expression in hypoxic EV-treated hADSCs. The same result was demonstrated by tube formation on Matrigel in vitro.

CONCLUSIONS

Hypoxic EVs significantly increased the proliferation and angiogenic differentiation potential of hADSCs. Hypoxic EV-treated ADSCs may be beneficial to CAL and prevascularized tissue-engineered constructs.

Ultra-condensed Fat: A Novel Fat Product for Volume Augmentation

BACKGROUND

Fat transplantation retention rate is individualized and unpredictable. The presence of blood components and oil droplets in the injected lipoaspirate increases inflammation and fibrosis in a dose-dependent manner, and is probably the key factor associated with poor retention.

OBJECTIVES

This study describes a volumetric fat grafting strategy based on optimization of grafts via screening intact fat particles and absorbing free oil droplets and impurities.

METHODS

Centrifuged fat components were analyzed by n-hexane leaching. A special device was applied to de-oil intact fat components and obtain ultra-condensed fat (UCF). UCF was evaluated by scanning electron microscopy, particle size analysis, and flow cytometric analysis. Histological and immunohistochemical changes were investigated in a nude mouse fat graft model over 90 days.

RESULTS

The lower 50% of centrifuged fat was concentrated to 40% of the original volume to obtain UCF. In UCF, the free oil droplet content was less than 10%, more than 80% of particles were larger than 1000 µm, and architecturally important fat components were present. The retention rate of UCF was significantly higher than that of Coleman fat on day 90 (57.5 ± 2.7% vs. 32.8 ± 2.5%, p < 0.001). Histological analysis detected small preadipocytes with multiple intracellular lipid droplets on day 3 in UCF grafts, indicative of early adipogenesis. Angiogenesis and macrophage infiltration were observed in UCF grafts soon after transplantation.

CONCLUSION

Adipose regeneration with UCF involves rapid macrophage infiltration and exit, resulting in angiogenesis and adipogenesis. UCF may serve as a lipofiller which is beneficial for fat regeneration.

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 http://www.springer.com/00266 .

Fat Grafting Reduces Skin Hyperpigmentation of Localized Scleroderma Patients: A Prospective Self-controlled Study

BACKGROUND

Localized scleroderma (LS) is characterized by skin fibrosis, hyperpigmentation and soft tissue atrophy. Fat grafting has been widely used to correct LS deformity.

OBJECTIVE

To investigate the effect of fat grafting on the skin pigmentation of LS lesions.

METHODS

A prospective self-controlled study was conducted. Skin melanin and erythema indexes were measured by Mexameter® MX18 before and 3 months after surgery. Differences between lesions and contralateral normal sites were compared to evaluate changes induced by fat grafting. Localized Scleroderma Cutaneous Assessment Tool and PUMC Localized Scleroderma Facial Aesthetic Index were used for clinical evaluation.

RESULTS

Fourteen frontal linear LS patients participated in the study. Before surgery, the melanin index of the lesions was significantly higher than the contralateral sites (p = 0.023), while the erythema indexes were not significantly different (p = 0.426). Three months post-operation, the melanin index of the lesions significantly decreased (p = 0.008). There was no significant change in the erythema index of the lesions before and after fat grafting (p = 0.322). The LoSCAT and PUMC LSFAI scores demonstrated improved disease condition and facial esthetics after surgery.

CONCLUSION

Fat grafting could alleviate skin hyperpigmentation and skin damage of LS lesions while having little effect on skin erythema and disease activity.

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 .

Clinical Application of Stromal Vascular Fraction Gel in Unilateral Vocal Fold Paralysis

PURPOSE

To investigate the therapeutic effect of the stromal vascular fraction gel (SVF gel) in unilateral vocal fold paralysis.

METHODS

A retrospective study was performed on 22 patients who underwent SVF gel autotransplantation for unilateral vocal fold paralysis between June 2017 and December 2018. Fat was removed from the medial thigh under anesthesia and the SVF gel was prepared using standard techniques and injected using a suspension microlaryngoscopy. The SVF gel was transplanted into the vocal fold muscle and the paraglottic space, and subjective and perceptual assessments, aerodynamic and acoustic assessments, and a videostroboscopic assessment were evaluated pre- and postoperatively at 1day, 12 months and 18 months.

RESULTS

The GRBAS evaluation results showed that the voice quality of the patients at 12 and 18 months after the operation was significantly improved, and voice analysis showed that in males maximum speech time (MPT) increased and the normalized noise energy decreased 1 day after surgery. The voice quality parameters at 12 months and 18 months after surgery improved significantly compared to preoperatively (P < 0.05), except for the fundamental frequency (F0), at 12 months, which was similar to the values before surgery. In females, the MPT and amplitude (shimmer) at 1 day after the surgery were significantly different from before the surgery, and the MPT, fundamental frequency (jitter), shimmer, and normalized noise energy at 12 months and 18 months after the surgery were significantly improved compared to before the surgery while the F0 was not significant.

CONCLUSION

SVF gel autotransplantation can effectively improve the voice quality in unilateral vocal fold paralysis, and the long-term effect is stable.

Safety and Aesthetics of Autologous Dermis-Fat Graft after Parotidectomy: A Multidisciplinary Retrospective Study

(1) Background: In surgical procedures for maxillofacial tumours, it is challenging to preserve functional and cosmetic properties in the affected patients. The use of fat grafting is considered as a valuable alternative to overcome postoperative aesthetic asymmetry problems. (2) Methods: In this study, we enrolled thirty patients with parotid gland tumours in which a partial or complete parotidectomy was performed with positioning in the parotid bed of autologous dermis-fat grafts. We evaluated the satisfaction rate of the patients and the objective efficacy in solving the deformity by comparing MRI data before and after surgery. (3) Results: Twenty-six patients showed a satisfying cosmetic result with proper facial symmetry between the affected side and the healthy one. Two patients presented mild postsurgical complications such as haematomas, and two patients reported temporary weakness of the facial nerve related to the parotidectomy. (4) Conclusions: Based on the imaging data obtained via MRI before and after surgery, we can assess that the employment of fat grafts in parotidectomy surgical procedures gives good cosmetic results and does not affect the post operative management and follow up of oncologic patients.

Autologous Fat Grafting: an Emerging Treatment Option for Complex Anal Fistulas

BACKGROUND

Autologous fat grafting (AFG) has shown promise in the treatment of complex wounds, with trials reporting good healing rates and safety profile. We aim to investigate the role of AFG in managing complex anorectal fistulas.

METHODS

This was a retrospective review of a prospectively maintained IRB-approved database. We examined the rates of symptom improvement, clinical closure of fistula tracts, recurrence, complications, and worsening fecal incontinence. Perianal disease activity index (PDAI) was obtained for patients undergoing combination of AFG and fistula plug treatment.

RESULTS

In total, 52 unique patients underwent 81 procedures, of which Crohn's was present in 34 (65.4%) patients. The majority of patients previously underwent more common treatments such as endorectal advancement flap or ligation of intersphincteric fistula tract. Fat-harvesting sites and processing technique were selected by the plastic surgeons based on availability of trunk fat deposits. When analyzing patients by their last procedure, 41 (80.4%) experienced symptom improvement, and 29 (64.4%) experienced clinical closure of all fistula tracts. Recurrence rate was 40.4%, and complication rate was 15.4% (7 postoperative abscesses requiring I&D and 1 bleeding episode ligated at bedside). The abdomen was the most common site of lipoaspirate harvest at 63%, but extremities were occasionally used. There were no statistically significant differences in outcomes when comparing single graft treatment to multiple treatments, Crohn's and non-Crohn's, different methods of fat preparation, and diversion.

CONCLUSION

AFG is a versatile procedure that can be done in conjunction with other therapies and does not interfere with future treatments if recurrence occurs. It is a promising and affordable method to safely address complex fistulas.

The Current State of Fat Grafting in the Hand: A Systematic Review for Hand Diseases

Autologous fat grafting (AFG) has traditionally been used for facial rejuvenation and soft tissue augmentation, but in recent years, its use has expanded to treat diseases of the hand. Autologous fat grafting is ideal for use in the hand because it is minimally invasive, can restore volume, and has regenerative capabilities. This review summarizes the emerging evidence regarding the safety and efficacy of AFG to the hand in several conditions, including systemic sclerosis, Dupuytren disease, osteoarthritis, burns, and traumatic fingertip injuries. A Preferred Reporting Items for Systematic Reviews and Meta-Analyses-compliant literature search on the use of AFG in hand pathologies was performed on October 8, 2020, in Ovid MEDLINE, Elsevier Embase, Clarivate Web of Science, and Wiley Cochrane Central Register of Controlled Trials. The retrieved hits were screened and reviewed by 2 independent reviewers and a third reviewer adjudicated when required. Reviewers identified 919 unique hits. Screening of the abstracts identified 22 manuscripts which described the use of AFG to treat an identified hand condition. Studies suggest AFG in the hands is a safe, noninvasive option for the management of systemic sclerosis, Dupuytren contracture, osteoarthritis, burns, and traumatic fingertip injuries. While AFG is a promising therapeutic option for autoimmune, inflammatory, and fibrotic disease manifestations in the hand, further studies are warranted to understand its efficacy and to establish more robust clinical guidelines. Studies to date show the regenerative, immunomodulatory, and volume-filling properties of AFG that facilitate wound healing and restoration of hand function with limited complications.

Stem Cell-Enriched Fat Grafts Versus Autologous Fat Grafts for Facial Reconstruction: A Systematic Review and Meta-analysis

OBJECTIVE

The aim of the study is to compare the outcomes of stem cell-enrichment fat grafting versus routine fat grafting for facial reconstruction purposes.

METHODS

A systematic review and meta-analysis were performed as per the Preferred Reporting Items for Systematic Reviews and Meta-analyses Guidelines and a search of electronic information was conducted to identify all randomized controlled trials, case control studies, and cohort studies comparing the outcomes of stem cell enrichment fat grafting versus routine fat grafting for facial reconstruction purposes. Volume retention and infection rate were primary outcome measures. Secondary outcome measures included patient satisfaction postsurgery, redness and swelling, fat necrosis, cysts, as well as operation time. Fixed and random effects modeling was used for the analysis.

RESULTS

Eight studies enrolling 275 subjects were selected. There was a significant difference between the stem cell enrichment fat grafting and routine grafting groups in terms of mean volume retention (standardized mean difference, 2.49; P < 0.00001). However, there was no significant difference between the 2 groups in the rate of infection (odds ratio, 0.36; P = 0.30). For all secondary outcomes, the intervention group had similar results compared with the control group except for the operation time, which was shorter in the latter.

CONCLUSIONS

Stem cell-enriched fat grafting is a superior option when compared with the routine fat grafting for facial reconstruction surgery because it improves the mean volume retention and does not worsen patient satisfaction and surgical complications.

Concentrated ultrasound-processed fat (CUPF): More than a mechanically emulsified graft

INTRODUCTION

Autologous fat grafting is still an evolving technique. Researchers have attempted to increase the survival rate of grafts by concentrating adipose-derived stem cells (ASCs). In this study, we investigate a novel method that combines ultrasonic processing and centrifugation to generate small fat particles termed concentrated ultrasound-processed fat (CUPF) for grafting.

METHODS

The standard approach for obtaining CUPF is described. The properties of processed fat, including CUPF, microfat, centrifuged fat, and nanofat, were investigated using histological observation. Comparative analyses were conducted on the cell number, viability, and immunophenotypic profile of stromal vascular fraction cells (SVFs). Cultured ASCs were evaluated for cell proliferation and adipogenic, osteogenic, and chondrogenic potential. The processed fats were transplanted and evaluated using in vivo and histological studies.

RESULTS

Compared with microfat, centrifuged fat, and nanofat, CUPF had a condensed tissue content and higher concentration of viable cells in a small tissue structure and could smoothly pass through a 27-gauge cannula. In the CUPF group, SVFs were isolated in great numbers, with high viability and a high proportion of CD29- and CD105-positive cells. ASCs from the CUPF group exhibited high proliferation and multilineage differentiation potential. The grafts from the CUPF group were well preserved, and histological quantification revealed an increase in the abundance of Ki67- and CD31-positive cells in the tissue.

CONCLUSIONS

Our study established a new fat processing strategy that combines ultrasonic processing and centrifugation to harvest small particle grafts named CUPF. CUPF concentrated a large number of ASCs and has great potential for regenerative therapy.

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

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

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

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

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

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

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

SUMMARY

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

CLINICAL RELEVANCE STATEMENT

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

Recent advances in surgical techniques for breast reconstruction

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

Evaluation of the Effect of Metoprolol Dosage on Fat Graft Survival

AIM

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

MATERIAL AND METHOD

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

RESULTS

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

CONCLUSION

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

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

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

BACKGROUND

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

METHODS

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

OUTCOMES

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

CONCLUSIONS

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

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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