Acute adipocyte viability after third-generation ultrasound-assisted liposuction

FAM-Fat Augmentation Mastopexy: A Method to Avoid Implants

BACKGROUND

Despite high complication rates, patients persistently present for single-stage augmentation mastopexy. In empty, deflated breasts, we perform one-stage augmentation mastopexy; however, in heavy ptotic breasts, our preference is to stage the procedure with mastopexy and fat graft first. With volume from fat grafting focussing on the upper pole and cleavage areas, many of our patients avoid implants altogether. This reduces subsequent risks of waterfall deformity, implant displacement, rupture and a lifetime of implant exchanges.

OBJECTIVES

We aim to describe our findings and technique for reducing progression to the second stage of a two-stage augmentation mastopexy with the appropriate use of moderate to high volume of fat grafting at the primary operation.

METHODS

This is a retrospective review of all patients who presented to the senior author (KT) requesting breast implants and requiring mastopexy, from January 2018 to December 2022.

RESULTS

Over the five-year period, 137 patients were identified. Seventy-one (51.8%) underwent single-stage augmentation mastopexy, 55 (40.1%) underwent mastopexy with fat grafting and 11 (8.0%) underwent mastopexy with no fat grafting. Our key finding in this study is that 52 of 66 (78.8%) of planned staged patients, who underwent mastopexy with or without fat grafting, were happy with the volume attained and no longer wished to undergo further implant augmentation.

CONCLUSION

In selected patients, appropriate volume and position of fat grafting at the time of primary mastopexy can significantly obviate the need for a second stage implant (alloplastic) augmentation.

LEVEL OF EVIDENCE V

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A randomized intraindividual comparative study evaluating the effects of two ultrasound-assisted liposuction devices on the abdomen

BACKGROUND

Ultrasound-assisted liposuction (UAL) has become popular because of its favorable outcomes in fat emulsification, blood loss reduction, and skin tightening. This study aimed to compare the effects of two UAL devices on the abdomen by assessing postsurgery skin biomechanical properties.

METHODS

This single-blind, prospective study (2020-2022) involved 13 liposuction procedures performed on patients without chronic diseases. Each patient's abdomen was divided vertically from the xiphoid to the perineum. Vibration amplification of sound energy at resonance (VASER)-assisted liposuction (Solta Medical, Inc., Hayward, CA) was performed on one half, while the other half underwent liposuction with high-frequency ultrasound energy (HEUS)-assisted technology. Skin biomechanical measurements, including distensibility, net elasticity, biological elasticity, hydration, erythema, melanin, and skin firmness, were taken at 12 and 24 months postsurgery, focusing on the anterior abdomen, 8 cm to the right and left of the umbilicus.

RESULTS

Analysis of the above skin biomechanical measurements revealed no significant differences between the HEUS and VASER devices, except for skin firmness, which showed a notable increase following HEUS surgery. Patient-perceived clinical differences were assessed via nonvalidated questionnaires, revealing no distinctions between devices.

CONCLUSION

Biomechanical skin results post-UAL surgery with these devices on the abdomen were not significantly different, although HEUS revealed increased skin firmness. This suggests that HEUS-assisted technology, akin to other devices, is a viable option for UAL procedures.

Mechanical Purification of Lipofilling: The Relationship Between Cell Yield, Cell Growth, and Fat Volume Maintenance

BACKGROUND

The mechanical manipulations of fat tissue represented from centrifugation, filtration, washing, and fragmentation were considered the most effective strategies aiming to obtain purified lipofilling with different impacts both in terms of adipose-derived stem cells amount contained in stromal vascular fraction, and fat volume maintenance.

OBJECTIVES

The present work aimed to report results in fat volume maintenance obtained by lipofilling purification based on the combined use of washing and filtration, in a clinical study, and to deeply investigate the adipose-derived stem cells yield and growth capacity of the different stromal vascular fraction extraction techniques with an in vitro approach.

METHODS

A preliminary prospective, case-control study was conducted. 20 patients affected by face and breast soft tissue defects were treated with lipofilling and divided into two groups: n = 10 patients (study group) were treated with lipofilling obtained by washing and filtration procedures, while n = 10 (control group) were treated with lipofilling obtained by centrifugation according to the Coleman technique. 6 months after the lipofilling, the volume maintenance percentage was analyzed by clinical picture and magnetic resonance imaging comparisons. Additionally, extracted stromal vascular fraction cells were also in vitro analyzed in terms of adipose-derived stem cell yield and growth capacity.

RESULTS

A 69% ± 5.0% maintenance of fat volume after 6 months was observed in the study group, compared with 44% ± 5.5% in the control group. Moreover, the cellular yield of the control group resulted in 267,000 ± 94,107 adipose-derived stem cells/mL, while the study group resulted in 528,895 ± 115,853 adipose-derived stem cells /mL, with a p-value = 0.1805. Interestingly, the study group showed a fold increase in cell growth of 6758 ± 0.7122, while the control group resulted in 3888 ± 0.3078, with a p < 0.05 (p = 0.0122).

CONCLUSIONS

The comparison of both groups indicated that washing and filtration were a better efficient system in lipofilling preparation, compared to centrifugation, both in terms of volume maintenance and adipose-derived stem cell growth ability.

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

Techniques in Facial Fat Grafting: Optimal Results Based on the Science of Facial Aging

SUMMARY

A thorough understanding of the science of facial aging is imperative to the precise and natural restoration of a youthful appearance. A hallmark of the aging process is fat atrophy. For this reason, fat grafting has become a keystone of the modern face lift. As a result, fat-grafting techniques have been refined to achieve optimal results. This is done through the differential use of fractionated and unfractionated fat throughout the face. This article reviews a single surgeon's technique for achieving optimal results in facial fat grafting.

Mechanical and Enzymatic Digestion of Autologous Fat Grafting (A-FG): Fat Volume Maintenance and AD-SVFs Amount in Comparison

BACKGROUND

Currently, several techniques for autologous fat graft (A-FG) preparation aimed at obtaining purified tissue exist. Both mechanical digestions via centrifugation, filtration, and enzymatic digestion were considered the most effective with different impacts in terms of adult adipose-derived stromal vascular fraction cells (AD-SVFs) amount that volume maintenance.

OBJECTIVES

This article aimed to report the in vivo and in vitro results, represented by fat volume maintenance and AD-SVFs amount, obtained by four different procedures of AD-SVFs isolation and A-FG purification based on centrifugation, filtration, centrifugation with filtration, and enzymatic digestion.

METHODS

A prospective, case-control study was conducted. In total, 80 patients affected by face and breast soft tissue defects were treated with A-FG and divided into four groups: n=20 were treated with A-FG enhanced with AD-SVFs obtained by enzymatic digestion (study group 1 [SG-1]); n=20 were treated with A-FG enhanced with AD-SVFs obtained by centrifugation with filtration (SG-2); n=20 were treated with A-FG enhanced with AD-SVFs obtained by only filtration (SG-3); n=20 were treated with A-FG obtained by only centrifugation according to the Coleman technique (control group [CG]). Twelve months after the last A-FG session, the volume maintenance percentage was analyzed by magnetic resonance imaging (MRI). Isolated AD-SVF populations were counted using a hemocytometer, and cell yield was reported as cell number/mL of fat.

RESULTS

Starting with the same amount of fat analyzed (20 mL), 50,000 ± 6956 AD-SVFs/mL were obtained in SG-1; 30,250 ± 5100 AD-SVFs/mL in SG-2; 33.333 ± 5650 AD-SVFs/mL in SG-3, while 500 AD-SVFs/mL were obtained in CG. In patients treated with A-FG enhanced with AD-SVFs obtained by automatic enzymatic digestion, a 63% ± 6.2% maintenance of fat volume restoring after 1 year was observed compared with 52% ± 4.6% using centrifugation with filtration, 39% ± 4.4% using only centrifugation (Coleman), and 60% ± 5.0% using only filtration.

CONCLUSIONS

In vitro AD-SVFs cell analysis indicated that filtration was the most efficient system-between mechanical digestion procedures-thanks to the highest amount of cells obtained with fewer cell structure damage, producing in vivo, the most volume maintenance after 1 year. Enzymatic digestion produced the best number of AD-SVFs and the best fat volume maintenance.

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

Consensus-based Recommendations for Vibration Amplification of Sound Energy at Resonance Ultrasound-assisted Liposuction

Ultrasound-assisted liposuction (UAL) is a popular and minimally invasive cosmetic procedure. Third-generation devices such as the vibration amplification of sound energy at resonance (VASER)lipo system are used for body contouring with enhanced tissue specificity. Despite the widespread use of VASER UAL, published guidelines and recent expert consensus recommendations are lacking. The objective of this study is to develop an expert consensus on the recommendations for use of VASER UAL.

Methods

In a modified Delphi process, a panel of five US-based, expert plastic surgeons participated in three rounds of consensus building that spanned 4 months to align on guidance statements for the use of VASER as an adjunct to liposuction.

Results

After the experts responded to an online questionnaire that assessed device settings, postoperative instructions, side effects or complications, and best practices, 32 initial consensus statements were developed. By round 3, these consensus statements for VASER UAL had been reduced and refined to a total of 18.

Conclusions

To improve patient outcomes, clinicians must understand key factors and best practices when using VASER UAL, including device settings, provider technique, managing side effects, potential complications, and postoperative care. The consensus statements developed herein aim to provide clinicians with expert-backed recommendations for the use of VASER UAL.

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.

Male Pectoralis Major Muscle Augmentation with Autologous Fat Transplantation Using VASER Lipoaspirate: Evaluation with MRI

The popularity of autologous fat grafts has increased for the reshaping, contouring, and augmentation of the male breast tissue. However, long-term maintenance of tissue viability and the ways for assessment serve as hot-spot topics in the field. This study was designed to evaluate the viability of fat grafts obtained by a vibration amplification of sound energy at resonance (VASER)-assisted lipoaspiration procedure using a magnetic resonance imaging-based approach.

Methods

This is a prospective examination of 20 male patients (40 breasts) who underwent VASER-assisted liposuction and fat grafting surgery, and long-term fat graft viability was evaluated by magnetic resonance imaging scans.

Results

Participants had an average age of 34.85 ± 7.37 years with a mean BMI of 26.73 ± 2.63 kg/m². The mean fat graft volume injected was 542.63 ± 144.78 mL on the right, and 548.95 ± 140.36 mL on the left side. On the magnetic resonance imaging follow-up, the mean intrapectoral adipose tissue thickness was 20.34 ± 6.31 mm on the right, and 18.94 ± 8.27 mm on the left sides and tissue viability was preserved in all cases. The mean follow-up duration was 22 ± 9.8 (range 14-44) months.

Conclusion

VASER-assisted lipoaspiration and autologous fat grafting of the major pectoralis muscle provide a satisfactory outcome and long-term maintenance of the grafted adipose tissue.

Characterization of Ultrasound Surgical Devices

This article is a review of the techniques for characterizing ultrasound surgical devices, as a guide to those undertaking a program of measurement, and as a basis for further standardization of those methods. The review covers both acoustic and nonacoustic measurements, with an emphasis on proper techniques, devices, and analyses according to the IEC Standard 61847. Low-frequency hydrophone measurements are presented, which are centered on simple acoustic theory. Inertial cavitation measurements are described based on detailed analyses of shock wave propagation. Cutting force tests are also presented as a basis for determining relative performance characteristics and determining mechanisms of action. Example data from each type of test are given. Comparison between acoustic output measurements, in vitro data, and clinical outcomes help establish that inertial cavitation is the predominant mechanism of soft tissue erosion and emulsification. The test results also demonstrate approaches to improving efficiency while minimizing undesired effects. Finally, recommendations are made for updates to the 61847 Standard and for other device labeling that would improve patient safety.

Quality and Vitality of Autologous Fat Grafts Harvested by Different Techniques: A Clinical Comparison Study

BACKGROUND

Unpredictable outcomes with autologous fat grafting due to reabsorption processes present a major challenge for healthcare providers and patients. A higher number of viable adipocytes is considered to result in a higher volume being retained. Although various adverse factors have been extensively researched, other potential parameters have been less investigated or even neglected.

OBJECTIVE

The aim of this study was to investigate the harvesting process of adipose tissue as the primary cause of cell damage and to determine the risk factors associated with low cell survival.

METHODS

Thirty-nine male and female subjects undergoing planned elective liposuction or abdominoplasty were enrolled. Forty-seven lipoaspirates harvested by different liposuction techniques were analyzed. RNA isolation and real-time polymerase chain reaction was performed to elucidate differences in the expression of various adipocyte markers. Furthermore, scanning electron microscopy was performed on various samples to determine the cell damage caused by the different techniques.

RESULTS

A statistically significant lower expression of peroxisome proliferator-activated receptor γ was detected in subjects with a higher BMI. A trend towards a lower expression of perilipin 1 in lipoaspirates harvested by a super wet + ultrasound technique, compared with dry and super wet techniques, was shown. The lowest level of cell damage determined from scanning electron microscopy images was in lipoaspirates harvested by the super wet + ultrasound technique, and this level was statistically significantly different from those obtained by the 2 other techniques.

CONCLUSIONS

Optimization of the outcome in autologous fat grafting may be feasible by targeting and optimizing the harvesting process as a main risk factor for impaired adipocyte viability. Ultrasound-assisted liposuction might be considered a suitable harvesting technique.

LEVEL OF EVIDENCE: 5

High-Quality Lipoaspirate Following 1470-nm Radial Emitting Laser-Assisted Liposuction

BACKGROUND

Laser-assisted liposuction (LAL) has been used to maximize viable adipocyte yields in lipoaspirates, although optimizing tissue processing methods is still a challenge. A high-quality lipoaspirate has been a key factor for extended graft longevity.

OBJECTIVE

To assess the viability and potency of stromal vascular fraction (SVF) cells and adipose-derived stem cells (ASCs) in fat samples from lipoaspirates harvested with a novel 1470-nm diode, radial emitting LAL platform. Two processing methods, enzymatic and nonenzymatic, were compared.

METHODS

Laser-assisted liposuction lipoaspirates harvested from 10 subjects were examined for cell viability after processing by enzymatic or nonenzymatic methods. Isolated SVF cells were cultured with an ASC-permissive medium to assess their viability and proliferation capacity by cell proliferation assay. Flow cytometric analysis with ASC-specific markers, gene expression levels, and immunofluorescence for ASC transcription factors were also conducted.

RESULTS

Lipoaspirates showed high SVF cell viability of 97% ± 0.02% and 98% ± 0.01%, averaged SVF cell count of 8.7 × 10 6 ± 3.9 × 10 6 and 9.4 × 10 6 ± 4.2 × 10 6 cells per mL, and averaged ASC count of 1 × 10 6 ± 2.2 × 10 5 and 1.2 × 10 6 ± 5 × 10 5 cells per mL in nonenzymatic and enzymatic methods, respectively. The ASC-specific markers, gene expression levels, and immunofluorescence for ASC transcription factors confirmed the adipose origin of the cells.

CONCLUSIONS

The laser lipoaspirates provide a high yield of viable and potent SVF cells and ASCs through both nonenzymatic and enzymatic processes. Improved purity of the harvested lipoaspirate and high ASC content are expected to result in extended graft longevity. Furthermore, eliminating enzymatic digestion may provide advantages, such as reducing process time, cost, and regulatory constraints.

Autologous Adipose-Derived Tissue Stromal Vascular Fraction (AD-tSVF) for Knee Osteoarthritis

Adipose tissue contains adult mesenchymal stem cells that may modulate the metabolism when applied to other tissues. Stromal vascular fraction (SVF) can be isolated from adipose tissue mechanically and/or enzymatically. SVF was recently used to decrease the pain and improve the function of knee osteoarthritis (OA) patients. Primary and/or secondary OA causes inflammation and degeneration in joints, and regenerative approaches that may modify the natural course of the disease are limited. SVF may modulate inflammation and initiate regeneration in joint tissues by initiating a paracrine effect. Chemokines released from SVF may slow down degeneration and stimulate regeneration in joints. In this review, we overviewed articular joint cartilage structures and functions, OA, and macro-, micro-, and nano-fat isolation techniques. Mechanic and enzymatic SVF processing techniques were summarized. Clinical outcomes of adipose tissue derived tissue SVF (AD-tSVF) were evaluated. Medical devices that can mechanically isolate AD-tSVF were listed, and publications referring to such devices were summarized. Recent review manuscripts were also systematically evaluated and included. Transferring adipose tissues and cells has its roots in plastic, reconstructive, and aesthetic surgery. Micro- and nano-fat is also transferred to other organs and tissues to stimulate regeneration as it contains regenerative cells. Minimal manipulation of the adipose tissue is recently preferred to isolate the regenerative cells without disrupting them from their natural environment. The number of patients in the follow-up studies are recently increasing. The duration of follow up is also increasing with favorable outcomes from the short- to mid-term. There are however variations for mean age and the severity of knee OA patients between studies. Positive outcomes are related to the higher number of cells in the AD-tSVF. Repetition of injections and concomitant treatments such as combining the AD-tSVF with platelet rich plasma or hyaluronan are not solidified. Good results were obtained when combined with arthroscopic debridement and micro- or nano-fracture techniques for small-sized cartilage defects. The optimum pressure applied to the tissues and cells during filtration and purification of the AD-tSVF is not specified yet. Quantitative monitoring of articular joint cartilage regeneration by ultrasound, MR, and synovial fluid analysis as well as with second-look arthroscopy could improve our current knowledge on AD-tSVF treatment in knee OA. AD-tSVF isolation techniques and technologies have the potential to improve knee OA treatment. The duration of centrifugation, filtration, washing, and purification should however be standardized. Using gravity-only for isolation and filtration could be a reasonable approach to avoid possible complications of other methodologies.

Safety and Efficacy of Third-Generation Ultrasound-Assisted Liposuction: A Series of 261 Cases

BACKGROUND

The introduction of third-generation ultrasound-assisted liposuction (3rd UAL) allows for a less invasive modality of both deep and superficial lipectomy while offering improved skin retraction and reduced rate of complications. This study examined the efficacy and safety profile of this technology over 15 years of clinical experience.

METHODS

A consecutive series of patients treated from 2005-2020 by the senior author were reviewed for demographic and anthropometric measurements, intraoperative settings, surgical outcomes, and complications via retrospective chart review. Body-Q survey was used to assess patient satisfaction.

RESULTS

A total of 261 patients underwent 3rd UAL in 783 areas. There were 238 female and 23 male patients with an average age of 43.5 years and BMI of 27.4 kg/m². The most frequently treated areas were the trunk and lower limbs. An average of 2840 mL of wetting solution was used with an average of 2284 mL of lipocrit aspirate. About 65% of the cases were done in conjunction with another procedure. Overall complication rate was 4.6%, contour irregularity (1.9%), seroma (0.8%), cellulitis (0.8%), pigmentation changes (0.4%), and electrolyte imbalance (0.4%), with a minimum follow-up of 6 months. 78% of patient would undergo the procedure again and 86% would recommend it.

CONCLUSION

Third-generation ultrasound-assisted liposuction can be used effectively and safely, either alone, or in conjunction with other plastic surgery procedures. VASER liposuction allows surgeons to address superficial fat plane and enhanced skin tightening. Rate of complications are lower than that of traditional liposuction with equivalent or higher patient satisfaction.

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 .

Evolving Clinical Experiences in Aesthetic Hip Implant Body Contouring

BACKGROUND

Hip augmentation increases the hip width using fat transfer and/or subcutaneous implants, creating a more feminine hourglass shape. Custom hip implant surgery requires proper patient selection, correct body frame analysis, appreciation of hip aesthetics, understanding surgical anatomy, optimal aesthetic planning, a favorable implant design and fabrication, skilled surgical implant placement, diligent postoperative patient care, and proper complication management.

OBJECTIVES

Evaluate the pioneering clinical experience with cosmetic custom hip silastic implants.

METHODS

Consecutive patient surgical series of patients seeking custom aesthetic hip implant surgery is tabulated. Similar hip analysis, implant design and fabrication, surgical technique, and postoperative follow-up was performed in three practices.

RESULTS

The overall patient satisfaction rate (87%, 47 of 54 patients) was favorable. There was a total of 29 (54%) medical complications and 20 (37%) cosmetic complications (implant show). A total of 17 patients (31.5%) requested revision surgery, secondary to implant show (n=10) and an infected implant (n=6). No patient experienced an acute implant infection, incisional scar hypertrophy, wound dehiscence, implant extrusion, parasthesias, muscle dysfunction, or hip joint injury.

CONCLUSIONS

The use of hip implants represents a new type of body contouring implant that has some unique differences in anatomic location, implant design, and tissue pocket location. Their use is an evolving one in aesthetic body implants, for which clinical experience to date remains limited in number. The proper surgical placement, postoperative management and treatment of complications to include revision surgery are essential to achieving a successful body contouring outcome.

The Effect of Ultrasonic Liposuction Energy Levels on Fat Graft Viability

BACKGROUND

The use of fat obtained from ultrasound-assisted liposuction is popular. However, no study has considered the effect of different energy levels on fat grafts.

OBJECTIVES

We hypothesized that different ultrasonic energy levels could change the fat graft viability.

METHODS

Both flanks of 15 CD1 nude mice (30 experimental areas) were used, with experimental areas randomly distributed into five groups. Using different energy settings, fat grafts were obtained from a patient's abdominoplasty material and applied to the mouse flank regions. Device settings were intermittent mode with 50% vibration amplitude in group 1, continuous mode with 50% vibration amplitude in group 2, intermittent mode with 90% vibration amplitude in group 3, and continuous mode with 90% vibration amplitude in group 4. The control group was grafted with fat obtained via the conventional method. After 6 weeks, all mice were sacrificed, and fat grafts were excised. Sections were stained with hematoxylin-eosin, Masson's trichrome, and anti-perilipin A antibody.

RESULTS

The perilipin A immunostaining result was lowest in group 4, indicating the lowest viable cell count (p < 0.01). There was no significant difference between groups for the other parameters (p > 0.05).

CONCLUSION

High ultrasonic energy may affect fat graft survival. If fat injection is planned, avoiding high energy settings (our recommendation is not to exceed 16 Watts.) should be considered. We also recommend increasing the vibration amplitude rather than switching from intermittent to continuous mode in body parts that are relatively resistant to liposuction.

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 .

Surgical Management of the Explant Patient: An Update on Options for Breast Contouring and Volume Restoration

BACKGROUND

Breast implant removal is becoming a common procedure in light of the current events and controversies with silicone breast implants. The authors believe strongly in informing patients about the indications and options regarding both explantation and the management of the secondary breast deformity.

METHODS

Relevant literature regarding the management of the explant patient was reviewed and organized to provide an update on prior publications addressing the explant patient population.

RESULTS

Surgical management options after implant removal include breast contouring and volume restoration. Fat augmentation has been used in both aesthetic and reconstructive breast surgery.

CONCLUSIONS

The authors review the surgical management for explantation, breast contouring, and autologous fat grafting for volume restoration. In the explant patient, autologous fat grafting serves as a reliable option for volume restoration.

Preclinical evaluation for removal of bulging lower eyelid fat using ultrasound-assisted lipolysis on a Yorkshire pig

PURPOSE

The purpose of this study is to evaluate the efficacy and safety of treating lower eyelid fat bulging with ultrasound-assisted lipolysis (UAL) by performing a preclinical evaluation of the procedure on a Yorkshire pig.

METHODS

Two white Yorkshire pigs had lower eyelid fat bulging treated with UAL using a probe with a diameter of 1.0 mm or less. Fourteen days after treatment, we evaluated the changes in fat thickness from ultrasound, changes in skin contour (volume and height) from the Antera 3D™, and the disruption of fat cells and changes in collagen synthesis from histological evaluation.

RESULTS

Fourteen days after treatment, the fat layer was significantly reduced with no damage to the skin surface. The mean change in the subcutaneous fat layer thickness was decreased 1.51-0.75 mm in ultrasound analysis. The skin contour of the treated area also decreased with time from 202.5 to 163.5 mm in mean volume and 0.8111 to 0.646 mm in mean height. Masson's trichrome staining showed that the UAL treatment induced the regeneration and remodeling of collagen.

CONCLUSION

The results of this study demonstrate that UAL successfully reduced the bulging lower eyelid fat of a Yorkshire pig and also increased collagen contraction to tighten skin. UAL may be a beneficial and well-tolerated treatment option for lower eyelid fat bulging.

Lipoplasty Combined with Percutaneous Radiofrequency Dermaplasty: A New Strategy for Body Contouring

BACKGROUND

A new technique in plastic surgery termed percutaneous radiofrequency dermaplasty (PRD) is described. Customized radiofrequency energy is applied via the percutaneous route to produce skin tightening and fascia contraction at body temperature, avoiding thermal injury. We combine PRD with lipoplasty and call this combined procedure dermaplasty-assisted lipoplasty (DAL). The purpose of this study was to review both the safety and efficacy of DAL.

METHODS

We developed the required novel device and technique to perform DAL and then performed a clinical trial including Type I and Type II lipodystrophy female patients undergoing a primary liposuction of the circumferential trunk. The trial comprised two phases. In Phase I, 51 patients were included in a prospective, comparative, controlled trial and divided into two groups. In Group 1, 29 patients underwent DAL, and in Group 2, 22 patients underwent a standard suction-assisted lipectomy (SAL) alone. In Phase II, 84 patients underwent DAL, including 9 cases initially scheduled for a mini-abdominoplasty.

RESULTS

Phase I: We found better aesthetic results with DAL (93.1%) than with SAL alone (72.7%) [p < .05]. Postoperative correction of flaccid skin was superior with DAL (93.1%) than with SAL alone (36.4%) [p < .01]. Phase II: DAL achieved good-to-excellent aesthetic results in 94% of the cases.

CONCLUSIONS

DAL was found to be a reliable and safe treatment for fat removal with concomitant skin and fascia tightening but without compromising the viability of the overlying skin.

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.

Impact of the Different Preparation Methods to Obtain Human Adipose-Derived Stromal Vascular Fraction Cells (AD-SVFs) and Human Adipose-Derived Mesenchymal Stem Cells (AD-MSCs): Enzymatic Digestion Versus Mechanical Centrifugation

Autologous therapies using adipose-derived stromal vascular fraction (AD-SVFs) and adult adipose-derived mesenchymal stem cells (AD-MSCs) warrant careful preparation of the harvested adipose tissue. Currently, no standardized technique for this preparation exists. Processing quantitative standards (PQSs) define manufacturing quantitative variables (such as time, volume, and pressure). Processing qualitative standards (PQLSs) define the quality of the materials and methods in manufacturing. The purpose of the review was to use PQSs and PQLSs to report the in vivo and in vitro results obtained by different processing kits that use different procedures (enzymatic vs. non-enzymatic) to isolate human AD-SVFs/AD-MSCs. PQSs included the volume of fat tissue harvested and reagents used, the time/gravity of centrifugation, and the time, temperature, and tilt level/speed of incubation and/or centrifugation. PQLSs included the use of a collagenase, a processing time of 30 min, kit weight, transparency of the kit components, the maintenance of a closed sterile processing environment, and the use of a small centrifuge and incubating rocker. Using a kit with the PQSs and PQLSs described in this study enables the isolation of AD-MSCs that meet the consensus quality criteria. As the discovery of new critical quality attributes (CQAs) of AD-MSCs evolve with respect to purity and potency, adjustments to these benchmark PQSs and PQLs will hopefully isolate AD-MSCs of various CQAs with greater reproducibility, quality, and safety. Confirmatory studies will no doubt need to be completed.

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

OBJECTIVE

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

DATA SOURCES

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

STUDY SELECTION

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

RESULTS

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

CONCLUSIONS

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

Effects of aspiration time on immediate viability of adipocyte cell in ultrasound-assisted liposuction (UAL) and in traditional suction-assisted lipectomy (SAL)

We aimed to determine the effect of aspiration periods following liposuction procedure on vascular structures, fibrocollagenous tissues and viability of adipose cells at different minutes, respectively in UAL and SAL. Abdominoplasty materials were divided into two equal parts from middle following excusion during the operations. Traditional SAL was performed to the right part of the abdominoplasty materials therewithal. Each side of the material was then divided into five parts enumarated from one to five and aspiration procedure time for each area was defined according to this ranking. The aspiration periods for each area were as follows: the transition intervals of 30 seconds between each zone were calculated as preoperative preparation time for surgical equipment in every area, and for discharging the lipoaspirates from collecting container. Red blood cell amount, a rate of degeneration in vasculary tissues, adipocyte cell amount with nuclear conformation, a rate of septal structure loss in fibroblast cells and septal fibroblast amount were the histopatological parametres of the study which observed and analysed by the pathologists. Based on the results of statistically analysis we proved that obtaining more surviving fat graft is possible by keeping aspiration period less than 2 minute in operation zone. In case of elongation of stated period clinical accomplishment of fat graft application reduces due to the downward of viable adipocyte cell amount and accelerating injury on tissues. Consequently, keeping the aspiration duration less than two minutes in planned liposuction area in both liposuction methods is favourable for providing maximum viable autologous fat graft.

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

Background

Cell-assisted lipotransfer (CAL) has been considered a promising technique for promoting adipogenesis and angiogenesis in fat grafts.

Objectives

The author sought to objectively analyze the change of breast volume in patients who underwent stromal vascular fraction (SVF)-enriched fat grafting for breast augmentation and compared the clinical results with those who underwent conventional fat grafting without SVF by using 3-dimensional laser scanning.

Methods

From April 2015 to March 2016, 105 patients who underwent traditional fat grafting without SVF enrichment for breast augmentation were assigned to group A and served as the control. The other 101 patients who underwent SVF-enriched fat grafting for breast augmentation were assigned to group B. The charts of these patients were retrospectively reviewed.

Results

The survival rate of the transplanted fat was 67.9% in group A and 68.7% in group B at 12 months after the operation. Postoperative complication rate was 3.8% in group A and 5.9% in group B. The differences were statistically insignificant.

Conclusions

SVF does not ensure a higher survival rate in autologous fat grafting for breast augmentation. Considering the potential drawbacks of adipose-derived stem cells (ADSC) and the extra cost of the consumables, in particular the need for harvesting larger amount of fat which could be reserved for additional fat grafting at a later time to achieve even better improvement, the results of this study do not support the use of SVF in autologous fat grafting for breast augmentation in terms of graft survival and postoperative complications.

Level of Evidence 3

Literature Review to Optimize the Autologous Fat Transplantation Procedure and Recent Technologies to Improve Graft Viability and Overall Outcome: A Systematic and Retrospective Analytic Approach

OBJECTIVE

Investigation and evaluation of the current methods and steps of autologous fat transplantation to optimize the viability of fat grafts and procedure outcome in quest of a more standardized protocol.

METHODS

A thorough literature search was performed across the CNKI, Wan Fang, PubMed, Ovid and EMBASE databases from the year 1970 to December 2014, collecting and classifying all of the autologous fat transplantation-related reports and articles, and after screening, a critical retrospective analysis was performed on the included data.

RESULTS

A total of 65 articles were included in the study. However, there were limited numbers of cases dealing with procedure-related steps such as the selection of donor sites, fat acquisition, graft treatment and methodology of transplant, resulting in a significant lack of evidence support, furthermore urging the need for more standardized protocol for the steps of autologous fat transplant to improve graft viability and overall outcome while decreasing procedure-related morbidity.

CONCLUSION

No good evidence was obtained to optimize the donor site, acquisition, processing and transplantation steps of the whole process of autologous fat transplantation. Tissue engineering and stem cell research have the potential to revolutionize the future of reconstructive surgery by replacing tissue, obviating the need for donor site morbidity. However, the use of stem cell therapies to expand and grow tissue for reconstruction must occur in the context of risk management. Balancing ease of harvest with yield and efficacy has been a delicate and often difficult trade-off which has prompted the scientific community to investigate alternative sources. However, there is much hope in the evaluation and implementation of multimodality approaches for autologous fat transplant, including thriving technologies such as ultrasound-assisted, water jet-assisted, nanotechnology-assisted liposuction in combination with revolutionary fat treatment technologies such as the VASER system.

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 .

Fat Grafting with Tissue Liquefaction Technology as an Adjunct to Breast Reconstruction

Background

Tissue liquefaction technology (TLT) delivers warmed saline from the liposuction cannula tip at low pressure pulses to disaggregate adipocytes. This technology differs significantly from that used in other liposuction devices including water jet-assisted liposuction. Here we introduce our early experience with this technology in the setting of fat transfer for revision breast reconstruction.

Methods

A retrospective chart review of 136 consecutive patients who underwent fat harvest with TLT and subsequent transfer into 237 breast reconstructions was conducted at a single institution. This two-surgeon series examined donor and recipient site complication rates over a median follow-up of 143 days [87–233].

Results

The overall complication rate was 28.7 %, of which the majority (22.1 %) was fat necrosis at the recipient site as documented by any clinical, imaging, or pathologic evidence. The abdomen served as the donor site for half of the cases. Donor site complications were limited to widespread ecchymosis of the donor site notable in 10.4 % of cases. Twenty-five percent of patients had received postmastectomy radiotherapy prior to fat transfer. Prior to revision with fat transfer, implant-based breast reconstruction was used in 75.5 % of cases, and autologous flaps in the remainder. Fat transfer was combined with other reconstructive procedures 94.1 % of the time.

Conclusions

TLT can be used to harvest adipocytes for fat transfer with donor site morbidity and recipient site complications comparable to other modalities. The efficiency and quality of harvested fat makes this technology appealing for wide spread adoption during fat transfer.

Level of Evidence IV

This journal requires that the 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.

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

BACKGROUND

Interest in and acceptance of autologous fat grafting for use in contour abnormalities, breast reconstruction, and cosmetic procedures have increased. However, there are many procedural variations that alter the effectiveness of the procedure and may account for the unpredictable resorption rates observed.

METHODS

The authors highlighted studies investigating the effects of harvesting procedures, processing techniques, and reinjection methods on the survival of fat grafts. This review focused on the impact different techniques have on outcomes observed in the following: in vitro analyses, in vivo animal experiments, and human studies.

RESULTS

This systemic review revealed the current state of the literature. There was no significant difference in the outcomes of grafted fat obtained from different donor sites, different donor-site preparations, harvest technique, fat harvesting cannula size, or centrifugation speed, when tumescent solution was used. Gauze rolling was found to enhance the volume of grafted fat, and no significant difference in retention was observed following centrifugation, filtration, or sedimentation in animal experiments. In contrast, clinical studies in patients found more favorable outcomes with fat processed by centrifugation compared with sedimentation. In addition, higher retention was observed with slower reinjection speed and when introduced into less mobile areas.

CONCLUSIONS

There has been a substantial increase in research interest to identify methodologies for optimizing fat graft survival. Despite some differences in harvest and implantation technique in the laboratory, these findings have not translated into a universal protocol for fat grafting. Therefore, additional human studies are necessary to aid in the development of a universal protocol for clinical practice.

Ultrasound-Assisted Liposuction Does Not Compromise the Regenerative Potential of Adipose-Derived Stem Cells

The regenerative abilities of adipose-derived mesenchymal stem cells (ASCs) harvested via a third-generation ultrasound-assisted liposuction (UAL) device versus ASCs obtained via standard suction-assisted lipoaspiration were evaluated. ASC yield and viability, and expression of most osteogenic, adipogenic, and key regenerative genes were equivalent between the two methods. Cells harvested via UAL showed comparable abilities to enhance cutaneous regeneration and appear suitable for cell therapy and tissue engineering applications.

Human mesenchymal stem cells (MSCs) have recently become a focus of regenerative medicine, both for their multilineage differentiation capacity and their excretion of proregenerative cytokines. Adipose-derived mesenchymal stem cells (ASCs) are of particular interest because of their abundance in fat tissue and the ease of harvest via liposuction. However, little is known about the impact of different liposuction methods on the functionality of ASCs. Here we evaluate the regenerative abilities of ASCs harvested via a third-generation ultrasound-assisted liposuction (UAL) device versus ASCs obtained via standard suction-assisted lipoaspiration (SAL). Lipoaspirates were sorted using fluorescent assisted cell sorting based on an established surface-marker profile (CD34+/CD31−/CD45−), to obtain viable ASCs. Yield and viability were compared and the differentiation capacities of the ASCs were assessed. Finally, the regenerative potential of ASCs was examined using an in vivo model of tissue regeneration. UAL- and SAL-derived samples demonstrated equivalent ASC yield and viability, and UAL ASCs were not impaired in their osteogenic, adipogenic, or chondrogenic differentiation capacity. Equally, quantitative real-time polymerase chain reaction showed comparable expression of most osteogenic, adipogenic, and key regenerative genes between both ASC groups. Cutaneous regeneration and neovascularization were significantly enhanced in mice treated with ASCs obtained by either UAL or SAL compared with controls, but there were no significant differences in healing between cell-therapy groups. We conclude that UAL is a successful method of obtaining fully functional ASCs for regenerative medicine purposes. Cells harvested with this alternative approach to liposuction are suitable for cell therapy and tissue engineering applications.

Significance

Adipose-derived mesenchymal stem cells (ASCs) are an appealing source of therapeutic progenitor cells because of their multipotency, diverse cytokine profile, and ease of harvest via liposuction. Alternative approaches to classical suction-assisted liposuction are gaining popularity; however, little evidence exists regarding the impact of different liposuction methods on the regenerative functionality of ASCs. Human ASC characteristics and regenerative capacity were assessed when harvested via ultrasound-assisted (UAL) versus standard suction-assisted liposuction. ASCs obtained via UAL were of equal quality when directly compared with the current gold standard harvest method. UAL is an adjunctive source of fully functional mesenchymal stem cells for applications in basic research and clinical therapy.

Enzymatic and non-enzymatic isolation systems for adipose tissue-derived cells: current state of the art

In the past decade, adipose tissue became a highly interesting source of adult stem cells for plastic surgery and regenerative medicine. The isolated stromal vascular fraction (SVF) is a heterogeneous cell population including the adipose-derived stromal/stem cells (ASC), which showed regenerative potential in several clinical studies and trials. SVF should be provided in a safe and reproducible manner in accordance with current good manufacturing practices (cGMP). To ensure highest possible safety for patients, a precisely defined procedure with a high-quality control is required. Hence, an increasing number of adipose tissue-derived cell isolation systems have been developed. These systems aim for a closed, sterile, and safe isolation process limiting donor variations, risk for contaminations, and unpredictability of the cell material. To isolate SVF from adipose tissue, enzymes such as collagenase are used. Alternatively, in order to avoid enzymes, isolation systems using physical forces are available. Here, we provide an overview of known existing enzymatic and non-enzymatic adipose tissue-derived cell isolation systems, which are patented, published, or already on the market.

Characterization of adipose tissue for autologous fat grafting

Fat grafting is a common procedure in aesthetic and reconstructive plastic surgery, but variable graft retention limits its utility. Unpredictable clinical outcomes with fat grafting can be explained in part by the lack of standardized protocols for harvesting, processing, and transplanting adipose tissue (AT). Historically, plastic surgeons have relied on trial and error and their clinical experience to develop fat grafting protocols. Optimization of fat grafting protocols requires systematic assessment of the impact that key variables have on the quality of the AT preparation at each step of the procedure. In this article, we review recent findings regarding the composition and quality of AT prepared for fat grafting and the strengths and limitations of existing AT characterization assays. We discuss the need for an assessment of the viability of intact AT (ie, conventionally harvested AT that has not been disrupted further) by means of an operator-independent, quantitative assay that can be performed in real time and generates reproducible data. Promising assays for the characterization of cell product quality have been developed for other therapeutic applications, such as transplantation of pancreatic islet cells. The development or adaptation of a gold-standard assay to determine the quality of an AT preparation may help to standardize fat grafting protocols and improve clinical outcomes.