Alexandra Condé-Green

Effects of Centrifugation on Cell Composition and Viability of Aspirated Adipose Tissue Processed for Transplantation

BACKGROUND Centrifugation is one of the preferred methods of fat processing. Although it has been promoted for nearly three decades to separate adipose tissue components before grafting, there remain many controversies regarding the results obtained with centrifuged adipose tissue. OBJECTIVES The authors demonstrate the effects of centrifugation on the cellular components of aspirated fat. METHODS Fat harvested from the lower abdomen of 10 female patients undergoing liposuction was divided in two equal parts, then processed by decantation or centrifugation and sent to the laboratory. Each processed lipoaspirate was analyzed histologically after hematoxylin and periodic acid-Schiff staining for the presence of intact adipocytes. It was then cultured and analyzed by multicolor flow cytometry for identification of adipose-derived mesenchymal stem cells. RESULTS The middle layer of the centrifuged lipoaspirate, which is used by many surgeons, showed a great majority of altered adipocytes and very few mesenchymal stem cells in comparison with the decanted sample, which maintained the integrity of the adipocytes and showed a greater number of mesenchymal stem cells. The pellet observed as a fourth layer at the bottom of the centrifuged lipoaspirate showed the greatest concentration of endothelial cells and mesenchymal stem cells, which play a crucial role in the angiogenic and adipogenic effect of the grafted tissue. CONCLUSIONS If centrifuged lipoaspirate is used, the pellet (rich in adipose-derived mesenchymal stem cells) and the middle layer should be employed to increase fat graft survival.

Incisional negative-pressure wound therapy versus conventional dressings following abdominal wall reconstruction: a comparative study.

BackgroundImprovements in surgical techniques have allowed us to achieve primary closure in a high percentage of large abdominal hernia repairs. However, postoperative wound complications remain common. The benefits of negative-pressure wound therapy (NPWT) in the management of open abdominal wounds are well described in the literature. Our study investigates the effects of incisional NPWT after primary closure of the abdominal wall. MethodsA retrospective chart review was performed for the period between September 2008 and May 2011 to analyze the outcomes of patients treated postoperatively with incisional NPWT versus conventional dry gauze dressings. Patient information collected included history of abdominal surgeries, smoking status, and body mass index. Postoperative complications were analyzed using &khgr;2 exact test and logistic regression analysis. ResultsFifty-six patients were included in this study; of them, 23 were treated with incisional NPWT, whereas 33 received conventional dressings. The rates of overall wound complications in groups I and II were 22% and 63.6%, respectively (P = 0.020). The rates of skin dehiscence were 9% and 39%, respectively (P = 0.014). Both outcomes achieved statistical significance. Rates of infection, skin and fat necrosis, seroma, and hernia recurrence were 4%, 9%, 0%, and 4% for group I and 6%, 18%, 12%, 9% for group II, respectively. ConclusionsThis study suggests that incisional NPWT following abdominal wall reconstruction significantly improves rates of wound complication and skin dehiscence when compared with conventional dressings. Prospective, randomized, controlled studies are needed to further characterize the potential benefits of this therapy on wound healing after abdominal wall reconstruction.

Significant predictors of complications after sternal wound reconstruction: a 21-year experience.

BackgroundWe sought to identify patient comorbidities that predict complications after tissue flap sternal reconstruction. MethodsA retrospective study, December 1989 to December 2010, analyzed numerous comorbidities, including diabetes mellitus (DM), hypertension (HTN), coronary artery disease, congestive heart failure (CHF), and renal insufficiency, as independent risk factors for postoperative complications. Pearson &khgr;2 test, Fisher exact test, 2-sample t test, and median-unbiased estimation were used for data analysis. Significance was P ⩽ 0.05. ResultsIn all, 106 patients received 161 sternal tissue flap repairs. Nineteen patients (18%) required reoperation because of complications, including recurrent wound infection, tissue necrosis, wound dehiscence, mediastinitis, and hematoma formation. Our analysis found DM, HTN, and CHF as significant predictors of complications after sternal reconstruction (P = 0.014, 0.012, and 0.006). ConclusionsResults suggest DM, HTN, and CHF may contribute to complications after tissue flap repair of sternal wounds, possibly through impaired perfusion and healing of repairs.

Shift toward Mechanical Isolation of Adipose-derived Stromal Vascular Fraction: Review of Upcoming Techniques

Background: Standard isolation of adipose stromal vascular fraction (SVF) requires the use of collagenase and is considered more than “minimally manipulated” by current good manufacturing practice requirements. Alternatively, nonenzymatic isolation methods have surfaced using physical forces to separate cells from the adipose matrix. The purpose of this study was to review the literature on the use of mechanical isolation protocols and compare the results. The implication for use as a standard procedure in practice is discussed. Methods: A systematic review of the literature was performed on mechanical isolation of SVF with a search of six terms on PubMed and Medline databases. One thousand sixty-six articles were subject to evaluation by predetermined inclusion and exclusion criteria. Results: Two level 2 evidence articles and 7 in vitro studies were selected. SVF was isolated using automated closed systems or by subjecting the lipoaspirate to centrifugation only or by shaking or vortexing followed by centrifugation. Six articles reported isolation in laboratory settings and three inside the operating room. Stromal vascular cells expressed CD34, and CD44, CD73, CD90, and CD105, and differentiated along adipogenic and osteogenic lineages. When compared with enzymatic methods, mechanical isolation required less time but yielded fewer cells. Both case–control studies reported improved volume retention with cell-supplemented fat grafts for breast reconstruction. Conclusions: Mechanical isolation methods are alternatives to circumvent safety issues posed by enzymatic protocols. However, randomized comparative studies with long-term clinical outcomes using mechanically isolated stromal vascular cells are needed to identify their ideal clinical applications.

Discussion: gluteoplasty with autologous fat tissue: experience with 106 consecutive cases.

1390 T art of autologous fat grafting requires understanding of key principles similar to the art of skin grafting. The procedure is composed of a series of discrete steps: choice of donor site, harvesting, processing, preparation of the recipient area, injection techniques, and postoperative care. Each of these steps has several variables that may have an impact on the degree of success of the intended outcome (i.e., fat engraftment).1 The authors present a prospective study involving 106 consecutive female patients who underwent gluteal sculpting with fat grafting and liposuction in a period of 3 years. They describe their technique as a combination of two surgical procedures: first, liposuction from areas with excess fat in the flanks, thigh roots, saddlebags, and subgluteal region; and second, lipoinjection superficially in the gluteal region to improve its shape from lateral to center, and deeper to expand and augment its volume. They harvested adipose tissue using tumescent infiltration with 3and 4-mm cannulas and decanted the lipoaspirate in a closed system for 30 minutes. Because tumescent infiltration requires thrice the amount of infiltration solution used in the superwet technique, the final lipoaspirate could be comparable to a washed lipoaspirate. The authors have managed to standardize their technique, as shown in their Video, Supplemental Digital Content 1, http://links.lww. com/PRS/B274), in order to obtain reproducible results. Additional details, such as the negative pressure used while harvesting, were not defined. The supernatant fat was then injected in a retrograde fashion using 1to 3-mm blunt cannulas attached to 60-cc syringes. The authors stress the importance of adequately removing excess fat in the lumbosacral region, avoiding large quantities of fat transfer (limiting their graft to a mean of 505 ml per gluteal region), and injecting in different planes and various directions. They critically examined their previous results and modified their techniques accordingly, avoiding injection of fat anterior to a lateral line dividing anterior and posterior hip. Their complications were similar to those described in the literature. No agreement exists as to the best way to perform each of the steps required in a fat grafting procedure to ensure maximal take and graft viability. Preferential donor sites have been reported as having greater cell concentrations2; some authors harvest fat with small 10-cc syringes or vacuum-assisted devices3; some process through centrifugation, washing, or draining the lipoaspirate before injection to obtain a consistent volume and better quality graft.4,5 Others inject fat with smaller syringes and cannulas in order to ensure transfer of small aliquots with each withdrawal to increase the surface area of contact between the grafted fat and the recipient tissue.6 The authors should be commended on their consistently outstanding aesthetic results, which are documented in a prospective manner with patient and physician ratings and excellent photography. They consistently obtained a slender waistline, a pleasant waist-to-hip ratio, and a natural projecting gluteal region. The concepts and techniques are well known for gluteoplasty,7 and the authors have honed their art systematically. In our hands, we have found that liposuction, autologous fat grafting, volume rearrangement, and gluteal reshaping provide great versatility, precision, and long-term results, with quick recovery and few complications. We use 10to 20-cc syringes connected to 2-mm cannulas for

Reply: adipocyte damage in relation to different pressures generated during manual lipoaspiration with a syringe.

The counting was then repeated in 10 fields, obtaining a mean percentage range of nonviable adipocytes. Despite the operator-dependent detection method, the results (Table 1) validate the observations of Rodriguez and Condé-Green and demonstrate a dramatic percentage increase of nonviable adipocytes comparing the sample at 5 and 10 cc (Fig. 1), whereas the maximum value of membrane rupture ( 75 percent) was recorded in sample D (30 cc of plunger pull-back). Our observations confirm that extreme care must be taken during the harvesting phase to avoid affecting the results of the entire procedure. In addition, we finally recommend to never exceed 5 cc of plunger pull-back during manual fat harvesting to guarantee the success of this operative procedure. DOI: 10.1097/PRS.0b013e3182827760

Plication of the Brachial Fascia: An Important Step in Dermolipectomy Procedures of the Arm

BACKGROUND Both the aging process and postobesity deformities of the upper extremities are associated with lipodystrophy, loss of muscular mass, weakening of the fascia, and skin laxity. Many different surgical procedures have been described to correct these deformities, but most of them have limitations, particularly with respect to postsurgical scarring. OBJECTIVES The authors present a technique in which plication of the brachial fascia is performed before dermolipectomy in order to obtain greater flap advancement and limit tension on the final scars, thereby diminishing postoperative complications. METHODS From 1997 to 2007, the authors retrospectively followed 41 female patients who had undergone brachial dermolipectomy procedures associated with plication of the fascia on the internal aspect of the arm. This technique permitted greater advancement of the entire thickness of the flap, creating a better support for the flap with larger skin resection. The distance between the two incisions was also shortened, reducing dead space between the two planes, the incidence of seromas, and tension on the suture line. RESULTS The scarring complications caused by tension on the skin were eliminated. Therefore, our complication rate was low, with only three cases of small foci of dehiscence, two cases of seroma, and four cases of hypertrophic scars in certain areas. The mean follow-up period was seven years, during which 92% of the patients were pleased with their outcomes. CONCLUSIONS The described surgical approach provided excellent overall extremity contour with favorable scars while simultaneously addressing axillary contour and forearm deformities when present.

Abstract: Subcutaneous Only Brazilian Butt Lift

RESULTS: The Danger Zone concept, already published by the authors to avoid MAFE, can also be applied to prevent MIFE, because it not only compromises the inferior gluteal vein, which is one of the main concern to be damaged and allow fat into bloodstream (MAFE) but also includes the muscle area with highest density of vessels in gluteal region that could allow absorption of free oil without direct vessel wall rupture (MIFE).

Abstract: Trends in Fat Grafting

M oday, O cber 1, 2018 with Fitzpatrick Skin Types II and III. Subjects received 3 combination treatments completed 30 days apart. Standardized photographs were taken at baseline and each followup. Improvement in wrinkles, texture and pigmentation was determined by masked, qualitative assessment of photographs at 90 days after last treatment compared to baseline. Clinician and Subject Global Aesthetic Improvement Scales (CGAIS, PGAIS), and a Patient Satisfaction Questionnaire were completed at 90 days after last treatment.

Commentary on: From Bedside to Bench: The Effect of Muscular Denervation on Fat Grafting to the Breast by Comparing Take Rate, Quality, and Longevity

While flap and implant-based procedures remain the primary methods of breast reconstruction, autologous fat grafting has become a common tool for the correction of contour irregularities and is gaining popularity for primary breast augmentation.1 The use of adipose tissue for these purposes has shown to be attractive because it is readily available, inexpensive, host compatible, can be harvested easily, and repeated as needed without worrying about allergic or foreign-body reaction.2 Unfortunately in practice, fat transplantation often has unreliable long-term results because of absorption and volume loss. As a result, several different techniques of lipoinjection have been developed in the last 30 years.3,4 All of the steps involved in the fat grafting procedure deserve close scrutiny, as each one may affect graft take. It is a chain of events that begins with the choice of donor site followed by harvesting, processing, and injection techniques; through the postoperative care; and recently the emphasis has been on preparing the recipient site to further improve graft take.5 Preconditioning the recipient site with tissue expansion or microneedling has shown increased angiogenesis and higher graft volume retention.6,7 The authors present a study in which they preconditioned the recipient area by denervating the muscular tissue chemically using botulinum toxin or mechanically by cutting out a nerve segment before performing fat grafting.8 They hypothesized that fat graft quality and longevity would be optimized in denervated muscle. Forty-two rats were grafted with fat explanted from their inguinal region, in their intact or denervated pectoralis muscle, or the subcutaneous tissue. Their results showed that in the intact nerve group, the percentage of viable fat cells in the subcutaneous layer was higher than in the intramuscular layer, and that intramuscular injection had a negative effect on the viability of grafted fat with the presence of more oil cysts. The authors should be commended on their idea and concept, as we never cease to explore methods that can improve and increase fat graft take. Fat grafting can be conceptualized in the same fashion as the stoichiometry of a chemical reaction, in which a fat droplet combines with a capillary receptor site, to result in a revascularized graft-recipient complex. A given amount of recipient site can accommodate only a limited amount of graft before the excess graft coalesces and necroses.9 Therefore, the graft-recipient site interface and the threshold pressure of the interstitial fluid are important components of fat graft take. As microdroplets are carefully inserted without coalescing, the recipient must stretch to accommodate the added volume. The pressure required for stretching the tissues is determined by their mechanical compliance, which varies among tissues and is not linear.10 As graft volume increases, interstitial pressure rises to levels that curb capillary perfusion. One of the preponderant factors for fat graft integration is the tissue