Fat Harvesting Research Articles

Commentary on: Superficial Enhanced Fluid Fat Injection (SEFFI) to Correct Volume Defects and Skin Aging of the Face and Periocular Region

I find the authors' historical view of clinical fat grafting mistaken, including their use of “micro” as definitive nomenclature, as well as their claim that the harvesting of fat with small side-hole cannulas (without further processing) is somehow novel. Coleman, as they indicate, indeed popularized modern fat grafting, by codifying a reproducible clinical technique that placed fat in a structural way—from deep to superficial—throughout the face with blunt needles, stressing the distribution of small fat parcels widely within a nutritive substrate. Equally important, he assured the survival of what many saw as another fad movement within plastic surgery through the presentation of impressive, long-term clinical results. He also developed and made available an instrument to support the new clinical activity. Early on, I, along with others1 (Dr F Benslimane, personal communication, 2001), had trouble with the large Coleman injection needles within the delicate suborbital zone. I responded by substituting a cumbersome but effective deep dermal–fat graft for a time, but eventually discovered an existing ophthalmologic McIntyre blunt, inner cannula: designed to irrigate the canaliculus, its delicate shaft fits easily within the Coleman injection needles and it has a blunt end and minute side hole, as I reported in 2001.2 Since its first use in 1999, I have had no visible irregularities within this challenging region. Soon after, I was introduced to a micro-infusion cannula with multiple small side-holes (also pre-existing and entirely similar to the authors' much later harvesters) by one of the manufacturers, which facilitated the harvest of smaller fat parcels for what I now called “micro” fat grafting to contrast with “macro” grafting by the original Coleman needles, which I continued to use only in the vein-rich environment of the dorsum of the hand. Virtually all manufacturers of fat-grafting equipment have long since added similar micro …

Autologous Fat Grafting in the Breast: Critical Points and Technique Improvements.

Breast augmentation or reconstruction is a major challenge in esthetic and reconstructive surgery. While autologous fat grafting (AFG) provides a natural filler and seems easy to harvest, AFG in breast surgery is still problematic especially due to the high resorption rate associated with megavolume transfer. Despite this pending issue, there is growing interest in this method, which is becoming more and more widespread, as can be seen by the recent increase in the number of clinical studies. This review aims to highlight recent knowledge in the technique of AFG to the breast and recent refined procedures to improve fat viability and long-term success of the graft. Clinical publications and trials of AFG to the breast from the past 5 years were examined. Attention was focused on the different AFG steps and the clinical outcomes, in order to highlight the strengths and weaknesses of the available protocols. Recent studies have concentrated on new techniques to improve fat viability and graft intake. However, all of these studies use different protocols at each step of the procedure. Furthermore, results may vary depending on the technique used for fat harvesting and processing. This review points out the recent advances in breast AFG techniques and their associated outcomes and complications. The bibliography has been carefully examined to reach a consensus so that recommendations could be made for each step of the technique with the aim of improving graft viability and long-term volume maintenance.

A Scanning Electron Microscope Study and Statistical Analysis of Adipocyte Morphology in Lipofilling

The aim of this study was to evaluate the effects on adipocyte morphology of 2 techniques of fat harvesting and of fat purification in lipofilling, considering that the number of viable healthy adipocytes is important in fat survival in recipient areas of lipofilling. Fat harvesting was performed in 10 female patients from flanks, on one side with a 2-mm Coleman cannula and on the other side with a 3-mm Mercedes cannula. Thirty milliliter of fat tissue from each side was collected and divided into three 10 mL syringes: A, B, and C. The fat inside syringe A was left untreated, the fat in syringe B underwent simple sedimentation, and the fat inside syringe C underwent centrifugation at 3000 rpm for 3 minutes. Each fat graft specimen was processed for examination under low-vacuum scanning electron microscope. Diameter (μ) and number of adipocytes per square millimeter and number of altered adipocytes per square millimeter were evaluated. Untreated specimens harvested with the 2 different techniques were first compared, then sedimented versus centrifuged specimens harvested with the same technique were compared. Statistical analysis was performed using Wilcoxon signed rank test. The number of adipocytes per square millimeter was statistically higher in specimens harvested with the 3-mm Mercedes cannula (P = 0.0310). The number of altered cells was statistically higher in centrifuged specimens than in sedimented ones using both methods of fat harvesting (P = 0.0080) with a 2-mm Coleman cannula and (P = 0.0050) with a 3-mm Mercedes cannula. Alterations in adipocyte morphology consisted in wrinkling of the membrane, opening of pore with leakage of oily material, reduction of cellular diameter, and total collapse of the cellular membrane. Fat harvesting by a 3-mm cannula results in a higher number of adipocytes and centrifugation of the harvested fat results in a higher number of morphologic altered cells than sedimentation.

A novel and innovative technique of using a disposable syringe and mesh for harvesting fat for structural fat grafting.

Background:Successful restoration of structure and function using autologous free fat grafts has remained elusive. Review of literature shows that various harvesting and preparation techniques have been suggested. The goal of these techniques is to obtain greater adipocyte cell survival and consequently more reliable clinical results.Materials and Methods:In our technique, a piece of mesh is kept at one end of the lipoaspiration syringe, which is then connected to the Suction pump. As one syringe fills, it is replaced by another one until the required amount of fat is obtained.Results:By using a polypropylene mesh in our technique, we can separate the transfusate from the harvested fat graft during harvesting itself. The fat graft thus obtained is dense and concentrated, with fewer impurities.Conclusion:Hence, we recommend our technique as a reliable method for extracting sterile emulsified fat in an economical way.

Abstract 16129: Feasibility and Safety of Treatment With an Intracoronary Infusion of Adipose Derived Regenerative Cells (ADRC) in Patients With an Acute ST-Elevation Myocardial Infarction (ADVANCE study)

Objectives: The ADVANCE clinical trial sought to define the safety, feasibility and efficacy of an intracoronary infusion of adipose derived regenerative cells in patients admitted with an acute ST-elevation myocardial infarction (STEMI) within 24 hours of successful primary PCI. Methods: In this randomized, double-blind, placebo-controlled trial (n=23, 2:1 randomization), within 24 hours of successful primary PCI following STEMI, a small volume liposuction was performed for fat harvest and ADRC isolation by an automated Celution® System, and intracoronary infusion within 12 hours of the liposuction. Results: 23 patients were enrolled to date (all male, age 58 years, BMI 28 kg/m 2 ). The liposuction procedure data are shown in the table TEMI patients were routinely treated with dual anti platelets and heparin. The decline in hemoglobin following the liposuction procedure from baseline over the 10 hours following the procedure was 10.2% ±7.6 (mean ± SD) Although two patients had >20% of Hb decline at anytime (maximum 20.8%), one of these patients returned to within 10% of baseline by 10 hours without transfusion. The liposuction procedure was completed in all but one patient (terminated early due to hypotension - resolved with termination of procedure). IC infusion of the ADRC suspension was performed successfully in all patients. No impediment of coronary TIMI flow was observed during or following cell infusion of these mesenchymal-like cells. No ventricular arrhythmias were observed during cell infusion. No major adverse cardiac or cerebral events (MACCE) occurred within 30 days of the procedures. Conclusion: Limited liposuction to harvest fat for ADRC stem cell isolation and subsequent intracoronary infusion of these autologous ADRCs can be performed safely in patients with acute STEMI under dual antiplatelets therapy, demonstrating feasibility of the therapeutic application of point-of-care cell therapy using ADRCs.

Autologous Fat Graft in the Reconstructed Breast: Fat Absorption Rate and Safety based on Sonographic Identification

BackgroundAutologous fat graft has become a useful technique for correction of acquired contour deformity in reconstructed breasts. However, there remains controversial regarding the efficacy and safety of the practice for reconstructive breast surgery.MethodsA retrospective review was performed on 102 patients who had secondary fat grafting after breast reconstruction. Fat harvest, refinement and injection were done by Coleman's technique. All patients were followed up postoperatively within 1 month and after 6 months including physical examination and ultrasonography. In 38 patients, the reabsorption rate was calculated by serial changes of thickness between skin and pectoral fascia in the ultrasonic finding. Locoregional recurrence rate was compared with control group of 449 patients who had breast reconstruction without fat graft in the same time period.ResultsAverage 49.3 mL fat was injected into each breast. The most common location of fat graft was upper pole, followed by axilla, lower and medial breasts. During 28.7 months of average follow-up period, 2.9% of total patients had symptoms of palpable mass on fat graft side and ultrasonography identified fat necrosis and cyst formation in 17.6% of the patients. Calculated fat reabsorption rate was 32.9%. Locoregional recurrence was occurred in 1 patient (0.9%) and the rate was not different significantly with control group (2%).ConclusionsAlthough further studies are required to provide surgeons with definitive guidelines for the implementation of fat grafting, we propose autologous fat graft is an efficient and safe technique for secondary breast reconstruction.

Application of microautologous fat transplantation in the correction of sunken upper eyelid.

Although fat grafting has been clinically applied by surgeons in esthetic and reconstructive surgery, it has widely evolved in processes such as harvesting, processing, and placement of fat, using the fat-grafting procedure, which dates back over 100 years. Surgeons frequently use fat grafting to recontour, augment, or fill soft-tissue defects, facial wrinkles, or skin problems such as depressions or scars. However, fat grafting has not been thoroughly understood and has not been conclusively standardized to ensure superior clinical results. This study was intended to determine the role of microautologous fat transplantation (MAFT) under evidence-based medicine, particularly in accurate delivery of small fat parcels. The research method involved the conceptualization of MAFT and the development of an innovative surgical instrument for fat placement. Clinically, 168 patients with sunken upper eyelids with multiple folds underwent this procedure. The major findings suggested that MAFT exhibits promising clinical results and offers a superior guideline for fat placement. Details of the technique and theoretical implications are also discussed. The therapeutic effects of MAFT and the long-term clinical results of patients with sunken upper eyelids with multiple folds indicated satisfactory outcomes. Based on the results, MAFT offers an alternative option to surgeons for performing fat grafting and provides a more favorable option for the benefit and welfare of patients by reducing the potential complications.

N-Acetylcysteine (NAC) Improves Free Autologous Fat Graft Survival

BACKGROUND: Autologous fat grafting is an increasingly popular technique for soft tissue reconstruction, but is limited by inconsistent graft take, under correction, and repeat procedures.1–3 The authors examined whether a widely available, clinically safe anti-oxidant, N-acetylcysteine (NAC), could be added to tumescent solution at time of harvest to improve fat graft survival in a mouse model. METHODS: Inguinal fat grafts were harvested from C57BL/6 mice using tumescent solution with or without NAC, and injected under recipient mouse scalps. Fat graft volumes were evaluated via microCT and Materialise’s Interactive Medical Imaging Control System (MIMICS) volumetric analysis at 4 days (baseline), and 1 and 3 months post-injection. Explanted grafts were weighed and evaluated histologically for vascularity and quality. Flow cytometric analysis (FACS) and MTT assays were performed on adipose-derived stem cells (ADSCs) exposed to oxidative stress (hydrogen peroxide) with and without NAC. The effect of NAC on proliferation of a preadipocyte cell line was also analyzed using Oil Red-O staining and qualitative polymerase chain reaction (qRT-PCR). RESULTS: N-acetylcysteine resulted in improved fat graft retention, with 46% take in NAC animals, compared to 17% in controls (p=0.027) (Figure 1).Figure 1: MIMICS three-dimensional reconstructions of control (left) and NAC (right) mice free fat grafts at 3 months post injection.Explanted grafts from the NAC group were significantly larger (46 vs. 8 milligrams, p<0.01) and had a 133% higher mean adipocyte density on histology (p<0.0001) than controls (Figure 2).Figure 2: Free fat graft weights at 4 days, 1 month, and 3 months of control versus NAC based on three-dimensional reconstructed micro-CT scans of the grafts In Vivo.No increase in vascularity was observed on histology. FACS analysis demonstrated that NAC protected ADSCs from oxidative stress in a dose-dependent manner. Combined exposure to both NAC and hydrogen peroxide led to a 200-fold increase in ADSC proliferation, significantly higher than with either agent alone. NAC significantly decreased the differentiation of pre-adipocyte cells into adipocytes compared to control (p<0.05). CONCLUSIONS: Addition of NAC to tumescent fluid for harvest of fat improves graft survival and quality in a mouse model. Our In Vitro findings suggest that this effect is the result of protection from oxidative stress and increased survival of ADSCs and adipocytes, while keeping the ADSCs in a pre-differentiation state to allow re-population of the graft over time. Thus, NAC is a clinically safe anti-oxidant that could be added to tumescent solution to improve fat graft survival over time, without any subsequent steps or additives ex vivo.

Gluteal reshaping in the massive weight loss patient.

Gluteal reshaping in the massive weight loss patient.

Acute Nasal Reconstruction With Forehead Flap After Dog Bite

Acute Nasal Reconstruction With Forehead Flap After Dog Bite

Immediate fat grafting in primary cleft lip repair

Successful cleft lip repair creates symmetric nasolabial morphology with minimal scar. Fat grafting is used in cosmetic and reconstructive settings to provide contour, condition tissue and aid healing. This study employs immediate fat grafting concurrent with primary cleft nasolabial repair. We hypothesize that simultaneous fat transfer is safe and may optimize the result. This retrospective analysis included a series of consecutive infants who underwent primary cleft lip repair with immediate fat grafting. Demographic and peri-operative details were recorded. Post-operative photographs were analyzed by three blinded reviewers (Al-Omari et al. and Asher-McDade et al.). Kappa statistics were employed to assess inter-rater reliability (Randolph and Watkins MW). 30 children, 37 sides (13 left, 10 right, 7 bilateral; 62% complete, 38% incomplete) who underwent cleft lip repair at Yale were included. 20 underwent nasolabial repair with simultaneous fat grafting. Mean age of repair was 3.5 mo (range 1.5-6.4). Fat was hand suctioned from the thighs (15 left; 2 right; 3 both) with mean yield of 2.1 cc (range 1-5 cc). An average of 1.4 cc (range 0.5-2.5 cc) was injected to the philtrum, vermillion, piriform and ala. No complications were experienced with lip repair, fat harvest or graft injection. Mean follow-up was 24.7 months (range 12.4-60.2 months). Postoperative photographic assessment revealed minimal residual cleft stigmata with inter-rater reliability. Each ordinal score was statistically significant compared fat grafted repairs to those without fat grafting (p < 0.05). Simultaneous fat grafting and cleft lip repair can be performed safely. The augmentation and modulation of scar formation may optimize results. Prospective comparison is necessary to further corroborate our findings. Therapeutic (Level IV).

The effects of immunological castration and corn dried distillers grains with solubles withdrawal on growth performance, carcass characteristics, fatty acid analysis, and iodine value of pork fat depots1,2

A total of 1,360 pigs were used in a 125-d study to determine the effects of corn dried distillers grains with solubles (DDGS) withdrawal after immunological castration (Improvest, Zoetis, Kalamazoo, MI) on growth performance and carcass fat quality of pigs. Pens of male pigs (initially 24 kg) were randomly allotted by BW and castration method (physically castrated [PC] or immunologically castrated [IC] barrows) to 1 of 3 diets with 8 replications per treatment and 27 to 29 pigs per pen. Treatments were arranged in a 2 × 3 factorial with main effects of castration method and diet (0% DDGS throughout, 30% DDGS throughout, or 30% DDGS through d 75 then no DDGS to d 125). Intact males were injected with Improvest on d 39 and 74 (IC). No castration method × diet interactions (P > 0.12) were observed for growth performance. Before the second Improvest injection (d 0 to 74), PC barrows had increased (P < 0.05) ADFI but were less efficient (P < 0.05) than intact males. After the second Improvest injection until the first marketing event (d 74 to 107), IC barrows had improved (P < 0.05) ADG and G:F compared with PC barrows. From d 0 to 107, IC barrows had improved (P < 0.05) ADG, G:F, and lower ADFI than PC barrows. The inclusion of 30% DDGS decreased (P < 0.05) G:F compared with pigs fed the control diet. For the period after the second Improvest injection (d 74 to 125), IC barrows had increased (P < 0.05) ADG, ADFI, and G:F compared with PC barrows. Overall (d 0 to 125), IC barrows had improved (P < 0.05) ADG and G:F and lower ADFI than PC barrows. The inclusion of 30% DDGS decreased (P < 0.05) G:F. Carcass yield was lower (P < 0.05) for IC than PC barrows. Pigs fed 30% DDGS throughout had decreased (P < 0.05) carcass yield; however, withdrawing DDGS from the diet on d 74 was effective at fully recovering the yield loss. Carcass fat iodine values (IV) were consistently higher (P < 0.05), regardless of fat depot or harvest time when 30% DDGS were included in the diet. Multiple 2-way interactions (P < 0.05) were detected between castration method, DDGS, depot, and time. Interactions were a result of fatty acid profiles changing more rapidly in backfat and belly fat than in jowl fat from d 107 to 125 and more dramatically in IC than PC barrows in the same period. This improvement from d 107 to 125 could be caused by the dilution of unsaturated fatty acids, specifically C18:2 and C18:3, due to rapid deposition of fat from de novo synthesis in IC barrows.

Jet-assisted fat transfer to the female breast: preliminary experiences

Background Nowadays, autologous fat grafting is used as a versatile tool for distinct touch-ups after performed breast reconstruction or aesthetic augmentation. Different approaches of fat harvest, filtering, and reinjection have been described in last three decades. After the first report in 2010, the Berlin Autologous Lipotransfer (BEAULI) method became one of the latest popular techniques in the field of large volume fat grafting. Preliminary experiences with the rising jet-assisted fat transfer in a large case series of two specialized European centers are presented.

Critical Need for Accurate and Quantitative Viability Assays to Optimize Fat Grafting Protocols

Outcomes following autologous fat grafting continue to be unpredictable. The lack of a standardized protocol for fat harvest, processing, and transplant produces variable graft retention rates. Plastic surgeons historically have relied on trial and error to modify their techniques.1 To optimize fat grafting protocols, systematic evaluation of each procedural step for its specific impact on adipose tissue (AT) viability is critically needed. Many assays have been developed to measure AT viability, but most measurements are neither accurate nor quantitative, are operator dependent, and have not helped correlate fat grafting protocols (or changes to protocols) with outcomes.1 AT viability has been estimated through visual assessment, membrane integrity staining, conventional histology, or special staining for apoptosis or mitochondrial function; all these techniques are largely semiquantitative, because the outcome still depends on the individual operator's evaluation of results. The …

Intraoperative use of enriched collagen and elastin matrices with freshly isolated adipose-derived stem/stromal cells: a potential clinical approach for soft tissue reconstruction

BackgroundAdipose tissue contains a large number of multipotent cells, which are essential for stem cell-based therapies. The combination of this therapy with suitable commercial clinically used matrices, such as collagen and elastin matrices (i.e. dermal matrices), is a promising approach for soft tissue reconstruction. We previously demonstrated that the liposuction method affects the adherence behaviour of freshly isolated adipose-derived stem/stromal cells (ASCs) on collagen and elastin matrices. However, it remains unclear whether freshly isolated and uncultured ASCs could be directly transferred to matrices during a single transplantation operation without additional cell culture steps.MethodsAfter each fat harvesting procedure, ASCs were isolated and directly seeded onto collagen and elastin matrices. Different time intervals (i.e. 1, 3 and 24 h) were investigated to determine the time interval needed for cellular attachment to the collagen and elastin matrices. Resazurin-based vitality assays were performed after seeding the cells onto the collagen and elastin matrices. In addition, the adhesion and migration of ASCs on the collagen and elastin matrices were visualised using histology and two-photon microscopy.ResultsA time-dependent increase in the number of viable ASCs attached to the collagen and elastin matrices was observed. This finding was supported by mitochondrial activity and histology results. Importantly, the ASCs attached and adhered to the collagen and elastin matrices after only 1 h of ex vivo enrichment. This finding was also supported by two-photon microscopy, which revealed the presence and attachment of viable cells on the upper layer of the construct.ConclusionFreshly isolated uncultured ASCs can be safely seeded onto collagen and elastin matrices for ex vivo cellular enrichment of these constructs after liposuction. Although we observed a significant number of seeded cells on the matrices after a 3-h enrichment time, we also observed an adequate number of isolated cells after a 1-h enrichment time. However, this approach must be optimised for clinical use. Thus, in vivo studies and clinical trials are needed to investigate the feasibility of this approach.

Autologous Fat Grafting

Recent advances in adipose cellular biology have repopularized autologous fat grafting as a method widely used in both reconstructive and aesthetic surgery. This review aims to summarize our current knowledge on autologous fat grafting emphasizing harvesting techniques and processing methods as well as current trends and approaches. A thorough search of earlier and recent literature until October 2013 was conducted using the terms autologous fat grafting, autologous fat transfer, lipoaspirate, lipoinjection, fat harvest, and lipotransfer in PubMed and ClinicalTrials.gov databases, and relevant English- and German-language articles were included. Findings were categorized in a step-by-step approach of the fat grafting procedure into indications, selection of donor site, techniques for harvesting, processing, and reimplantation of autologous fat. Further in-depth knowledge will provide definite answers on fat graft survival; demonstrate safe methods to increase cell viability, grafting outcome predictability; and reliability; enhance safety; and strengthen the scientific and clinical establishment of this increasingly promising method.

Differential fat harvesting

Aim: Volume replacement with fillers is regularly performed with the use of diverse volumetric materials to correct different structures around the face, depending on the volume enhancement required and the thickness of the soft tissue envelope. Differential fat harvesting and posterior grafting is performed to place the correct fat parcel size for each target area, expanding the potential applications of fat. Methods: Sixty patients consecutively recruited on a first come basis undergone a facial fat grafting procedure, in private practice setting between March 2012 and October 2013. Fat grafting quantity and quality was predicted for each case. Differential harvesting was performed, with 2 fat parcels size. Processing was performed through washing. Fat infiltration was carried out through small cannulas or needles depending on the treated area. Outcomes were analysed both by the physicians and the patients at 7 days, 1 month, 3 months and 6 months through a perceived satisfaction questionnaire. Parameters considered were downtime or discomfort, skin benefits, volume restoration, reabsorption rate estimated and overall improvement. Results: Full facial differential fat grafting procedure lasted an average of 1.5-2.5 h. Average downtime was 3-4 days. Follow-up was performed to a minimum of 6 months. Both patient and physician overall satisfaction rates were mostly excellent. Adverse events like lumps or irregularities were not encountered. Conclusion: Differential fat harvesting and posterior grafting is a valid alternative, to expand the repertoire of fat use, allow a more homogeneous effect, reduce the potential complications, speed up the process, improve graft survival, and to enhance overall aesthetic outcome.

Current Fat Grafting Practices for Cosmetic and Reconstructive Breast Surgery

INTRODUCTION: Fat grafting is a popular procedure for breast surgeons yet variable techniques and results are reported.1 We surveyed members of the American Society of Plastic Surgery to elucidate current practice patterns and opinions to identify priorities for future investigation. METHODS: Six thousand letters were mailed (February 2012) followed several weeks later by an email reminder to the 5,942 members with valid addresses. Polling was closed on May 30, 2012 with 590 responses and 527 fully completed surveys. RESULTS: A large majority of responders perform this procedure (n=380, 69.3%). Safety concerns were cited as the most common reason for not performing fat grafting (43.4%). The majority of surgeons performed fat grafting for reconstructive (96.3%) indications with most avoiding the contralateral breast (72.7%). Reconstruction included deformities due to lumpectomy (64.1%) or mastectomy (66.6%), contour irregularities following both implant (93.4%) and tissue (88,4%) reconstruction. Cosmetic indications included augmentation with implant (45.5%) and without implant (48.5%), contour deformities post-augmentation (82.2%), and tuberous breast deformity (25.7%). The preferred donor site was the abdomen (79.9%), then thighs, flanks/back, and gluteal region. The top three fat harvesting techniques were manual aspiration (49.6%), wet liposuction (27.9%), and Lipivage (8.4%). Most employ tumescent solution (78.3%) or local anesthetic (11.4%). Liposuction cannulas are preferred over the syringe/needle for harvest (92.7 vs. 7.3%). Various cannulas are used: Coleman microcannula (21.5%), 1 mm (5.9%), 2 mm (29.4%), 3 mm (47.1%), 4 mm (22.6%), 5 mm (2.4%), and other (1.2%). Fat processing was predominantly centrifugation (28.5%) and filtration (42.4%) using either telfa/gauze or a strainer. Both fat freezing for delayed use (2.2%) and stem-cell enrichment techniques (3.3%) were uncommon. Most surgeons (56.4%) believed fat survival is 50-75% and only 7.9% believe survival is 75-100%. Overcorrection is routinely performed by 78.2% of surgeons and they report adding up to 25% volume (69.7%), 25-50% (27.9%), and greater than 50% (2.4%). Repeat sessions were performed mostly at 3-6 months (45.8%). CONCLUSION: Fat grafting is a promising surgical technique for breast surgeons but lacks standardization in clinical practice. ASPS members remain concerned about safety of this technique and possible oncologic concerns likely limit its use during reconstruction on a contralateral native breast. Further studies are needed to define optimal techniques in fat harvesting, donor-site selection, fat processing, injection technique/volume, and timing to improve safety and obtain reliable results.

Power assisted liposuction to obtain adipose-derived stem cells: Impact on viability and differentiation to adipocytes in comparison to manual aspiration

Adipose-derived stem cells (ASCs) play a key role in tissue engineering approaches and are probably of major importance in the context of autologous fat transfer. A number of different tools for harvesting ASCs-containing fat tissue have been established. Such devices should be easy to handle, time saving, low priced, safe and provide a high amount of viable ASCs in the aspirate. Power-assisted liposuction (PAL) has not yet been described in the literature as a tool for fat harvesting for lipotransfer. Aim of this study was to investigate ASCs' viability in fat tissue harvested using PAL versus manual aspiration (MA). Fat tissue was obtained from 9 donors undergoing abdominoplasty. Samples were divided into two sections. Out of each section fat was harvested using either PAL or MA. Number of isolated ASCs was defined, proliferation rate was determined and cell viability was assessed by flow cytometry. The ability of isolated ASCs to differentiate into mature adipocytes was analyzed by gene marker expression. The number of viable ASCs and the proliferation rates did not significantly differ between PAL and MA but cells harvested using PAL showed significantly higher expression levels of differentiation markers adiponectin, GLUT4 and PPARg. Our results show that PAL is a feasible method for harvesting fat tissue containing viable ASCs. Quantity and quality of PAL-harvested ASC is similar or even better, respectively, compared to ASCs harvested by MA.

Management of Tracheostomy Scar by Autologous Fat Transplantation

Tracheotomy is a life-saving operation but may have bothersome sequelae. Because the defect resulting from tracheostomy is often allowed to repair spontaneously by secondary intention, hypertrophic scar formation is a frequent consequence. Furthermore, skin-to-trachea adhesions may develop, creating a "tracheal tug," that is, the skin movement in conjunction with the trachea, causing discomfort on swallowing. The aim of this study was to verify whether lipofilling could treat the aesthetic and functional disturbances by remodeling tracheostomy scars. Ten patients, aged 20 to 51 years, with retracted and/or hypertrophic tracheostomy scar underwent fat injection under local anesthesia or sedation. Fat harvesting was by a 2-mm blunt cannula connected to a 10-mL syringe. Before inserting the refined fat with a 19-gauge cannula, the fibrotic bands of the retracted scar between skin and underlying tissue were released with a sharp needle. The procedure required 2 sessions with an interval of 6 to 12 months. In the first session, 3.0 to 10 mL of fat were inserted. A further 3 to 5 mL were delivered during the second course. In 3 cases, scar excision was performed under local anesthesia as a final procedure. All 10 patients achieved an aesthetic and functional improvement and were satisfied with the result at long-term follow-up (mean, 21.3 months). Fat grafting proved to be a safe, minimally invasive, and effective procedure for the treatment of the tracheostomy scar both for functional and aesthetic purposes. It can be considered as a valid alternative to major open surgery.