Influence of Closed-incision Negative Pressure Wound Therapy on Abdominal Site Complications in Autologous Breast Reconstruction.

Background: Closed-incision negative pressure wound therapy (ciNPWT) has shown promise in reducing surgical wound complications. Among its numerous benefits, it allows for exudate management and tension offloading from wound edges. The purpose of this systematic review and meta-analysis was to assess the efficacy of prophylactic ciNPWT versus conventional dressings on abdominal donor site complications in microsurgical breast reconstruction (MR). Methods: A systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in January 2023. PubMed and Embase were searched to identify all relevant studies. Data collected included rates of total wound complications, wound dehiscence, infection, seroma, and length of hospital stay. Results: A total of 202 articles were screened, and eight studies (1009 patients) met the inclusion criteria. Use of ciNPWT was associated with a significantly lower rate of wound dehiscence (OR, 0.53; 95% confidence interval, 0.33-0.85; P = 0.0085, I2 = 0%). There was no significant difference in the rate of total wound complications [odds ratio (OR), 0.63; 95% CI, 0.35-1.14; P = 0.12, I2 = 69%], donor site infection (OR, 0.91; 95% CI, 0.42-1.50; P = 0.47, I2 = 13%), seroma (OR, 0.74; 95% CI, 0.22-2.49; P = 0.63, I2 = 57%), or length of hospital stay (SMD, 0.089; 95% CI, -0.13-0.35; P = 0.37, I2 = 29%). Conclusions: Although exudate management by ciNPWT fails to reduce surgical site infection, seroma formation, and overall length of stay, ciNPWT tension offloading properties seem to be associated with lower rates of wound dehiscence when compared with conventional dressings in abdominal-based autologous breast reconstruction.

Extent of Tissue Washing Can Significantly Alter the Composition of Adipose-Derived Stromal Vascular Fraction Cell Preparations: Implications for Clinical Translation.

Stromal vascular fraction (SVF) cell preparations have recently attracted much interest as a form of autologous cell therapy. These heterogenous cell populations typically include some proportion of blood-derived cells (BDCs)-including both red blood cells (RBCs) and leukocytes (WBCs). The objectives of this paper were to evaluate the effects of tissue washing and hypotonic RBC lysis-separately and together-on BDC concentrations within SVF, and further to explore whether BDCs can confer detectable and modifiable effects on adipose-derived cell activity. Using various cell culture assays, flow cytometry and ELISA analysis of human-derived SVF preparations, we show that thorough washing of adipose tissue prior to enzymatic dissociation effectively removes RBCs from SVF preparations as well as standard lysis methods and significantly alters the type and relative quantities of WBCs. In addition, these studies demonstrate that potentially toxic RBC components are detectable for up to 1 week in cultures containing RBC lysate, but not those with intact RBCs, and, that culture-expanded cells proliferate significantly more in the presence of intact RBCs versus RBC lysis products or control media. Broadly, these data exemplify how different seemingly mundane tissue processing steps can significantly influence SVF identity/composition, purity, and potency. Based on the findings of this work, we propose that translational efforts in the field would benefit by a better understanding of the impact of RBCs, WBCs, and non-viable cells on the in vivo therapeutic activity of SVF therapies.

The Language of Implant-based Breast Reconstruction: Can We Do Better?

The management of breast cancer has experienced tremendous changes in the last half-century. In today's multimodal approach to breast cancer, patients have the prospect of achieving a sense of normalcy after mastectomy thanks to advancements in oncology and breast reconstruction. Although the oncologic management of breast cancer has evolved over multiple centuries, implant-based breast reconstruction (IBBR) has only been around since the 1960s. The last half century has seen the conception of multiple techniques, novel devices, and new possibilities in hopes of achieving outcomes that are similar to or even better than the patient's premorbid state. However, with all these changes, a new problem has arisen-inconsistencies in the literature on how IBBR is described. In this article, we will discuss potential sources of confusion in the IBBR literature and lexicon, highlighting specific terms that may have multiple meanings or interpretations depending on perspective, context, and/or intent. As a first step toward clarifying what we perceive as a muddied landscape, we propose a naming convention for IBBR that centers around four important variables especially pertinent to IBBR-the type of mastectomy performed, the timing of reconstruction, the type of device that is placed, and the pocket location for device placement. We believe that adoption of a more standardized, consistent, and descriptive lexicon for IBBR will help provide clearer communication and easier comparisons in the literature so that we may continue to deliver the best outcomes for our patients.

The Effect of Fat Grafting on Expansion Pressures in Expander-Based Postmastectomy Breast Reconstruction: Outcomes in Normal and Irradiated Tissues.

INTRODUCTION: The impact of fat grafting on the viscoelasticity of irradiated tissues is poorly defined. We investigate the effect of subcutaneous fat grafting on postmastectomy tissue expansion in patients undergoing delayed breast reconstruction. We quantify observed viscoelastic and trophic changes of the skin envelope. We hypothesize that fat grafting changes the trophic and viscoelastic properties of the breast soft tissue envelope. METHODS: Postmastectomy defects delayed more than 2 years and reconstructed with subpectoral tissue expanders were prospectively studied. Control (no irradiation, no fat grafting, n = 7), fat grafted (no irradiation, fat grafting n = 8), and irradiated plus fat grafting (irradiation, fat grafting, n = 9) groups were included. Hydrostatic pressures of the tissue expanders were measured before and immediately after expansion, and again postexpansion day 1. Pressure changes calculated as "postexpansion-relaxation interval": difference between maximal pressure at each expansion and the minimal pressure before the next expansion session. Differences were analyzed between groups. RESULTS: Hydrostatic pressure plots reflect the soft tissue ability to accommodate sequential expansion. Fat grafted breasts demonstrated a statistically significant increased postexpansion-relaxation interval versus the nongrafted control group (P < 0.0001). Irradiated plus fat grafting breasts achieve similar postexpansion relaxation interval to the control group (P = 0.597). These changes are observed at postoperative week 6. Viscoelastic changes impact the overall expansion time: the fat grafted group achieved total expansion 2 weeks earlier than the nongrafted control group (P = 0.019). The fat grafted, radiated group completed expansion in similar time interval as nongrafted control group. CONCLUSIONS: Observed viscoelastic changes impact the overall expansion time. Fat grafting in nonradiated mastectomy defects allows for shorter expansion period. Fat grating in radiated postmastectomy defects allows expansion durations equivalent to nonradiated, nonfat grafted control defects. There is a delayed effect of fat grafting observed at postoperative week 6.

Safe Composite Calf Augmentation: A Staged Procedure.

BACKGROUND: Calf augmentation can be achieved by fat grafting, calf implants, or a combination of both methods (composite augmentation). For safety reasons, it is important to be aware of important calf anatomic features, specific physiologic considerations, and some health conditions that can hinder the outcome of these procedures. OBJECTIVES: The aim of this study was to present our experience with performing composite calf augmentation, and to describe indications, surgical techniques and safety issues. METHODS: We retrospectively analyzed 63 patients who had undergone composite calf augmentation for cosmetic and reconstructive surgery in our practice. We reviewed group demographics, complications, and results, and identified all the pitfalls encountered in our cases. Additionally, dissection of the calf regions in fresh cadavers was performed to obtain more accurate anatomy. We also measured intracompartmental pressures before and after calf augmentation with implants in 6 cases to determine pressure changes. RESULTS: All cases received subfascial implant insertion and fat grafting as a delayed procedure. If there is a need for multiple implants, we recommend a staged procedure. Our study showed high muscle sensitivity to pressure increase after augmentation. Hence, from the standpoint of safety, we advocate subcutaneous fat grafting only. No patients developed compartment syndrome. CONCLUSIONS: Composite calf augmentation surgery is safe and easy to reproduce, with a short recovery period and a low complication rate when done as a staged procedure and respecting specific anatomic and physiologic calf features.

A clinical perspective on adipose-derived cell therapy for enhancing microvascular health and function: Implications and applications for reconstructive surgery.

Restoration of form and function requires apposition of tissues in the form of flaps to reconstitute local perfusion. Successful reconstruction relies on flap survival and its integration with the recipient bed. The flap's precariously perfused hypoxic areas undergo adaptive microvascular changes both internally and in connection with the recipient bed. A cell-mediated, coordinated response to hypoxia drives these adaptive processes, restoring a tissue's normoxic homeostasis via de novo vasculogenesis, sprouting angiogenesis, and stabilizing arterialization. As cells exert prolonged and coordinated effects on site, their use as biological agents merit translational consideration of sourcing angio-competent cells and delivering them to territories enduring microcirculatory acclimatization. Angio-competent cells abound in adipose tissue: a reliable, accessible, and expendable source of adipose-derived cells (ADC). When subject to enzymatic digestion and centrifugation, adipose tissue separates its various ADC: A subset of buoyant oil-dense adipocytes (the tissue's parenchymal component) accumulates on a supra-natant layer, whereas the mesenchymal component remains in the infra-natant sediment, containing the tissue's stromal vascular fraction (SVF), where angio-component cells abound. The SVF can be further manipulated, selected, or culture expanded into more specific stromal subsets (herein defined as adipose stromal cells, ASC). While promising clinical applications for ADC await clinical proof and regulatory authorization, basic science investigation is needed to elucidate the specific ADC mechanisms that influence microvascular growth, remodeling, and function following flap surgery. The objective of this article is to share the clinical perspectives of reconstructive plastic surgeons regarding the use of ADC-based therapies to help with flap tissue integration, revascularization, and wound healing. Specifically, the focus will be on considering the potential for ADC as therapeutic agents and how their clinical application motivates basic science opportunities.

Human Stromal Cell Aggregates Concentrate Adipose Tissue Constitutive Cell Population by In Vitro DNA Quantification Analysis.

BACKGROUND: Regenerative cell strategies rely on stromal cell implants to attain an observable clinical outcome. However, the effective cell dose to ensure a therapeutic response remains unknown. To achieve a higher cell dose, the authors hypothesized that reducing the volume occupied by mature adipocytes in lipoaspirate will concentrate the stromal vascular fraction present in the original tissue. METHODS: Human standardized lipoaspirate (n = 6) was centrifuged (1200 g for 3 minutes) and the water phase was discarded. Mechanical disaggregation was achieved by shearing tissue through 2.4- and 1.2-mm Luer-to-Luer transfers. After a second centrifugation (800 g for 10 minutes), stromal cell aggregates were separated from the supernatant oil phase. Lipoaspirate percentage composition was determined by its constituent weights. Cell content was measured by total DNA quantification, and partial cell viability was determined by image cytometry. Tissue sections were evaluated histologically (hematoxylin and eosin and Masson trichrome stains). RESULTS: Stromal cell aggregates reduced the standardized lipoaspirate mass to 28.6 ± 4.2 percent. Accordingly, the cell density increased by 222.6 ± 63.3 percent (from 9.9 ± 1.4 million cells/g to 31.3 ± 6.6 million cells/g; p < 0.05). Cell viability was unaffected in stromal cell aggregates (71.3 ± 2.5 percent) compared to standardized lipoaspirate (72.2 ± 2.3 percent), and histologic analysis revealed high-density areas enriched with stromal cells (622.9 ± 145.6 percent) and extracellular matrix (871.2 ± 80.3 percent). CONCLUSION: Stromal cell aggregates represent a biological agent that triplicates the cell density versus unprocessed lipoaspirate, low on oil and water fluids, and enriched extracellular matrix components.

Arguments for a Different Regulatory Categorization and Framework for Stromal Vascular Fraction.

Although adipose tissue and cells show considerable promise for clinical translation in the emerging field of regenerative medicine, they present a challenge to the regulatory community both nationally and internationally. This commentary evaluates the status of adipose-derived therapeutics and considers regulatory approaches designed to maximize patient safety while advancing clinical translation in accordance with evidence-based medical science.

Nanofat Cell Aggregates: A Nearly Constitutive Stromal Cell Inoculum for Regenerative Site-Specific Therapies.

BACKGROUND: Recent technology developed by Tulip Medical Products allows clinicians to mechanically disaggregate fat tissue into small fat particles known as nanofat. The present study aimed to evaluate the cell yield obtained from nanofat generation in comparison to traditional methods involving enzymatic dissociation (stromal vascular fraction). METHODS: Nanofat preparations were characterized by cell content and viability, based on DNA quantification and image cytometry, respectively. DNA analysis was also used to determine the cell content in unprocessed dry lipoaspirate and native adipose tissue (excised adipose tissue). To evaluate cell yield, the authors compared the number of cells recovered from 1 g of lipoaspirate between stromal vascular fraction and nanofat preparations, and subsequently determined the final cell inoculum obtained following their respective protocols. RESULTS: The data showed that nanofat samples presented a cell burden of 7.3 million cells/g, close to 80 percent of unprocessed dry lipoaspirate, and 70 percent of native excised adipose tissue. Moreover, cell viability was not altered by mechanical disaggregation in nanofat samples compared to unprocessed dry lipoaspirate. Nanofat samples exhibited a cell yield of 6.63 million cells/g lipoaspirate, whereas stromal vascular fraction preparations resulted in only 0.68 million cells/g lipoaspirate. The final cell inoculum obtained from stromal vascular fraction isolation was 120 million cells and it required 200 to 250 cc of raw lipoaspirate as starting material, whereas nanofat preparation resulted in 125 million cells with only 20 cc of raw lipoaspirate. CONCLUSION: Mechanical disaggregation offers a better cell inoculum than conventional enzymatic dissociation methods by using 10 times less fat tissue as starting material and delivering a higher cell yield.

Aesthetic Improvement of Undeveloped Calves After Treatment of Congenital Clubfoot Deformity.

BACKGROUND: Even when clubfoot deformity is treated in a timely manner, the consequences observed in adulthood include hypoplasia of the calf muscles, gait impairment, decreases in foot size, and it can also affect the tibial length. These consequences may have negative impacts on the patient's subjective appraisal of long-term outcomes, and can influence the patient's self-esteem in both male and female patients. OBJECTIVES: We present our experience in the treatment of undeveloped calves after surgical treatment of congenital clubfoot. METHODS: In total, 72 patients underwent corrective surgery in order to improve undeveloped calves resulting from a congenital clubfoot deformity. We used calf silicone implants in combination with fat grafting in multistaged procedures, in order to decrease complication rates and improve aesthetic outcome. RESULTS: Amongst our patients there were 54 (75%) females and 18 (25%) males. All of the patients, except one, had unilateral calf hypoplasia. The procedures were divided into several groups: (1) medial calf augmentation with silicone implants; (2) medial calf augmentation with silicone implants and fat grafting; and (3) medial and lateral calf augmentation with silicone implants and fat grafting. We had one case of a hyperpigmented scar and one case of partial scar dehiscence. There were no cases of compartment syndrome. The average follow-up period was 9.8 months. CONCLUSIONS: Calf enhancement surgery in patients with congenital clubfoot deformity is very gratifying. When combining calf implants with fat grafting in multistaged procedures, we can achieve excellent results with low complication rates.

Gland Suspension Improves Breast Augmentation Outcomes.

BACKGROUND: While dual plane breast augmentation successfully addresses low ptosis grades, concomitant hypomastia and greater ptosis often requires combined immediate or staged mastopexy with extended incisions beyond those required for breast augmentation. In an attempt at offering a minimal scar in a single procedure, we evaluated the benefit of a gland suspension maneuver in addition to a dual plane dissection and implant placement to improve breast contour, avoid postoperative ptosis, and thus reduce staged reintervention procedures. METHODS: A consecutive group of 73 patients presenting ptotic hypomastia were jointly categorized and underwent implant placement, dual plane dissection level 3, and gland suspension maneuver. An age, implant volume, ptosis degree matched historical cohort was used as control (no gland suspension). All subjects were followed longer than 1 year postoperatively. Outcome analysis included reintervention rates and objective geodesic changes using objective morphometric parameters as measured by 3D scan analysis. RESULTS: When experimental and control cohorts were segregated according to ptosis grade, gland suspension maneuver was associated to a lower frequency of subsequent ancillary mastopexy procedures (reintervention rate) for all ptosis grades except ptosis grade III. When gland suspension was compared with ptosis equivalent control groups, gland suspension was associated to a higher upper pole volume increment and higher pole convexity and lower pole morphometry. CONCLUSION: The addition of gland suspension to implant dual plane breast augmentation appears to be a clinically beneficial maneuver with measurable contour impact and appears to avoid subsequent mastopexy procedures, except for high ptosis grade candidates.

Reproducible Volume Restoration and Efficient Long-term Volume Retention after Point-of-care Standardized Cell-enhanced Fat Grafting in Breast Surgery.

UNLABELLED: Lipoaspirated fat grafts are used to reconstruct volume defects in breast surgery. Although intraoperative treatment decisions are influenced by volume changes observed immediately after grafting, clinical effect and patient satisfaction are dependent on volume retention over time. The study objectives were to determine how immediate breast volume changes correlate to implanted graft volumes, to understand long-term adipose graft volume changes, and to study the "dose" effect of adding autologous stromal vascular fraction (SVF) cells to fat grafts on long-term volume retention. METHODS: A total of 74 patients underwent 77 cell-enhanced fat grafting procedures to restore breast volume deficits associated with cosmetic and reconstructive indications. Although all procedures used standardized fat grafts, 21 of the fat grafts were enriched with a low dose of SVF cells and 56 were enriched with a high SVF cell dose. Three-dimensional imaging was used to quantify volume retention over time. RESULTS: For each milliliter of injected fat graft, immediate changes in breast volume were shown to be lower than the actual volume implanted for all methods and clinical indications treated. Long-term breast volume changes stabilize by 90-120 days after grafting. Final volume retention in the long-term was higher with high cell-enhanced fat grafts. CONCLUSIONS: Intraoperative immediate breast volume changes do not correspond with implanted fat graft volumes. In the early postoperative period (7-21 days), breast volume increases more than the implanted volume and then rapidly decreases in the subsequent 30-60 days. High-dose cell-enhanced fat grafts decrease early postsurgical breast edema and significantly improve long-term volume retention.

Adipose tissue and stem/progenitor cells: discovery and development.

"Adipose tissue is a valuable, exploitable, appealing source of regenerative cells that can be used for a variety of clinical challenges. This article reviews the history of the development of adipose-derived cell science, particularly in the context of tissue engineering and regenerative medicine. It describes some of the advancements made in the field, as well as highlighting challenges and obstacles."

Age influence on stromal vascular fraction cell yield obtained from human lipoaspirates.

BACKGROUND AIMS: The adipose stromal vascular fraction (SVF) is a heterogeneous population of mononuclear cells that includes approximately 1-10% mesenchymal stromal cells. These SVF cells can be freshly obtained from human lipo-aspirates and represent and ideal candidate for regenerative medicine applications. In the present study, we analyzed the SVF yield as a function of the patient's age. METHODS: Adipose tissue samples from 52 informed subjects (all women) were processed by means of an innovative point-of-care technology for SVF isolation (GID platform). After enzymatic dissociation of adipose tissue and SVF pellet resuspension, we measured the concentration of mononucleated cells as well as other cell quality analyses on the cell suspension obtained. We then calculated the cell yield as total nucleated cells per milliliter of dry adipose processed. RESULTS: The mean SVF yield obtained was 7.19 × 10(5) ± 2.11 × 10(5) total nucleated cells per milliliter of adipose tissue. Our results show that there is a clear statistically significant decline in SVF cell yield with increasing age. CONCLUSIONS: Because all samples were obtained from the same donor area and the isolation technique used was the same in all cases, we conclude that the SVF cell yield in women is affected by patient age. Specific age-related factors should be analyzed in the future to explain these results.

The iliacus muscle flap: an anatomical and clinical evaluation.

BACKGROUND: The iliacus muscle is proposed as a new solution for coverage of small to medium defects where either a bulky flap or conspicuous donor sites are undesirable. METHODS: Dissection and Microfil studies were performed on fresh cadavers to define the gross and microvascular anatomy of the muscle. Live evaluation of the muscle was performed in combination with multiple iliac crest free tissue transfer procedures. The muscle was then used as a free flap in four separate cases to cover difficult extremity wounds. It was used as a pedicled flap in conjunction with a free iliac crest in a fifth case to assist with a composite mandible and facial defect. RESULTS: The iliacus originates from the inner aspect of the iliac crest and then fuses with the psoas at the level of the inguinal ligament. Its primary blood supply derives from a large branch off of the deep circumflex iliac artery. The isolated muscle resulted in a pancake-like flap measuring approximately 8 × 8 cm with a 6- to 8-cm pedicle (deep circumflex iliac artery). The muscle was then used clinically both as isolated free flaps and as a pedicled flap in conjunction with a free iliac crest. All flaps survived, resulting in healed wounds without complication. CONCLUSIONS: These results demonstrate that the iliacus is a new muscle that should be added to the microsurgeon's choices for free tissue transfer. It is easily harvested, has a large and well-defined pedicle, and is less prone to donor-site complications than some other muscles typically used for free tissue transfer.