Preconditioning strategies for improving the outcome of fat grafting.

Autologous fat grafting is a common procedure in plastic, reconstructive and esthetic surgery. However, it is frequently associated with an unpredictable resorption rate of the graft depending on the engraftment kinetics. This, in turn, is determined by the interaction of the grafted adipose tissue with the tissue at the recipient site. Accordingly, preconditioning strategies have been developed following the principle of exposing these tissues in the pre-transplantation phase to stimuli inducing endogenous protective and regenerative cellular adaptations, such as the up-regulation of stress-response genes or the release of cytokines and growth factors. As summarized in the present review, these stimuli include hypoxia, dietary restriction, local mechanical stress, heat and exposure to fractional carbon dioxide laser. Preclinical studies show that they promote cell viability, adipogenesis and angiogenesis, while reducing inflammation, fibrosis and cyst formation, resulting in a higher survival rate and quality of fat grafts in different experimental settings. Hence, preconditioning represents a promising approach to improve the outcome of fat grafting in future clinical practice. For this purpose, it is necessary to establish standardized preconditioning protocols for specific clinical applications that are efficient, safe and easy to implement into routine procedures.

The Influence of Inset and Shaping of Abdominal-Based Free Flap Breast Reconstruction on Patient-Reported Aesthetic Outcome Scores-A Systematic Review.

Background: Nowadays, multimodal cancer therapy results in very high survival rates of early-stage breast cancer and microsurgical flap-based breast reconstruction has become safe and reliable, with gradually increasing demand because of its durable and aesthetically pleasing results. This study aimed to explore the impact of different flap shaping and inset techniques on patient-reported outcome measures (PROMs) with regard to the aesthetic result in abdominal flap-based breast reconstruction. Methods: A systematic review was performed screening Pubmed, Cochrane Library and Web of Science for original articles reporting flap inset strategies, concomitantly providing PROMs on the aesthetic result. Results: Of 319 studies identified, six met the inclusion criteria. The studies described different flap rotation options according to the patient's morphology, different inset planes, and avoidance of the monitoring skin paddle, and suggested that a higher flap-to-mastectomy mass ratio was associated with better aesthetic results. In two comparative studies, according to the PROMs (BREAST-Q, Likert scale) and independent observer judgement, both higher patient satisfaction and superior aesthetic results were observed with the newly described techniques. Conclusions: Emphasis on the aesthetic outcome in terms of breast shape and symmetry, providing an individualized approach of flap inset, considering the contralateral breast's shape and volume, results in higher satisfaction scores.

Short-Term Periodic Fasting Reduces Ischemia-Induced Necrosis in Musculocutaneous Flap Tissue.

Periodic fasting (PF) as a form of dietary restriction has been shown to induce tissue-protective effects against ischemic injury in several different tissues. Accordingly, in this study we analyzed whether a short-term 24 h fast is suitable to prevent necrosis of musculocutaneous flap tissue undergoing acute persistent ischemia. C57BL/6N mice were randomly divided into a PF group (n = 8) and a control group that was given unrestricted access to standard chow (n = 8). The PF animals underwent a 24 h fast immediately before flap elevation and had unrestricted access to food for the rest of the 10 day observation period. Musculocutaneous flaps with a random pattern design were dissected on the animals' backs and mounted into dorsal skinfold chambers. On days 1, 3, 5, 7 and 10 after surgery, nutritive tissue perfusion, angiogenesis and flap necrosis were evaluated using intravital fluorescence microscopy. Thereafter, the flap tissue was excised and fixed for histological and immunohistochemical analyses. The flaps of PF-treated animals exhibited a higher functional capillary density and more newly formed microvessels, resulting in a significantly increased flap survival rate. Moreover, they contained a lower number of myeloperoxidase (MPO)-positive neutrophilic granulocytes and cleaved caspase-3-positive apoptotic cells in the transition zone between vital and necrotic flap tissue. These findings indicate that short-term PF improves tissue survival in ischemically challenged musculocutaneous flaps by maintaining nutritive blood perfusion and dampening ischemia-induced inflammation.

Is free nipple grafting necessary in patients undergoing reduction mammoplasty for gigantomastia? A systematic review and meta-analysis.

BACKGROUND: Gigantomastia is a debilitating condition characterised by an excessive breast tissue growth impacting patients' quality of life. Surgically treatment options include the limited-length pedicle (LP) technique with free nipple grafting (FNG) and the elongated pedicle (EP) technique, which maintains continuity of the nipple-areola complex (NAC). Initially, despite the less satisfactory aesthetic outcome, FNG was preferred to treat hypertrophic breasts requiring resections over 1000 g of parenchymal and adipose tissue, due to concerns about NAC perfusion. Recently, many studies have questioned this indication. The aim of this study was therefore to evaluate the safety of the NAC-carrying EP technique in patients with gigantomastia eventually challenging the need for FNG. METHODS: A literature search using PubMed and Cochrane databases was performed, including studies describing the outcome of EP technique for resection exceeding 1000 g of breast tissue. Thereby, a meta-analysis was conducted to evaluate the rate of NAC necrosis, whereas a descriptive statistic was applied to assess all other surgery-associated complications. RESULTS: Twenty-five studies, encompassing 1355 patients (2656 breasts), were included. EP demonstrated an extremely low rate of NAC necrosis. Moreover, the analysis demonstrated a low rate of ischaemia-independent complications and a very high probability of maintaining NAC-sensation equal to the preoperative state. CONCLUSION: Current evidence indicates that the EP technique should be the preferred surgical method to treat gigantomastia with or without massive ptosis whenever indicated. It has proven to be safe. Furthermore, it yields superior aesthetic and functional outcomes, including breast feeding and preservation of NAC-sensation compared to the LP technique.

Nanofat Accelerates and Improves the Vascularization, Lymphatic Drainage and Healing of Full-Thickness Murine Skin Wounds.

The treatment of wounds using the body's own resources is a promising approach to support the physiological regenerative process. To advance this concept, we evaluated the effect of nanofat (NF) on wound healing. For this purpose, full-thickness skin defects were created in dorsal skinfold chambers of wild-type mice. These defects were filled with NF generated from the inguinal subcutaneous adipose tissue of green fluorescent protein (GFP)+ donor mice, which was stabilized using platelet-rich plasma (PRP). Empty wounds and wounds solely filled with PRP served as controls. Wound closure, vascularization and formation of granulation tissue were repeatedly analyzed using stereomicroscopy, intravital fluorescence microscopy, histology and immunohistochemistry over an observation period of 14 days. PRP + NF-treated wounds exhibited accelerated vascularization and wound closure when compared to controls. This was primarily due to the fact that the grafted NF contained a substantial fraction of viable GFP+ vascular and lymph vessel fragments, which interconnected with the GFP- vessels of the host tissue. Moreover, the switch from inflammatory M1- to regenerative M2-polarized macrophages was promoted in PRP + NF-treated wounds. These findings indicate that NF markedly accelerates and improves the wound healing process and, thus, represents a promising autologous product for future wound management.

Complications Associated with Facial Autologous Fat Grafting for Aesthetic Purposes: A Systematic Review of the Literature.

Background: With the increasing demand for aesthetic procedures, autologous fat grafting (AFG) seems to be an attractive option for facial volumization and rejuvenation. The aim of this study was to assess the type and severity of associated complications after facial AFG for aesthetic purposes. Methods: The entire PubMed/Medline and Cochrane databases were screened to identify studies describing complications that occurred after the injection of autologous fat into the face. These complications have been reviewed and analyzed according to their occurrence and severity in the different anatomical regions of the face. Results: Twenty-two articles including 38 patients reported on a total of 58 complications. Thirty-two complications have been classified as severe or permanent, including hemiplegia (n = 11), loss of vision (n = 7), or skin necrosis (n = 3). The other 26 complications were classified as mild or transient, such as lipogranuloma (n = 12) or mycobacterial abscess (n = 2). The majority of complications were reported after injection to the forehead (n = 26) and the temporal region (n = 21). Interestingly, this location seems to be the area at risk because 53% of all severe complications occurred in this anatomical region. Conclusions: AFG to the face is associated with a low incidence of complications, but if they occur, they can be dramatic, particularly in the forehead and temporal region. Nevertheless, AFG can be used to correct age-related changes of the face and volume loss and may represent an alternative to synthetic fillers. Therefore, AFG to the face should be performed by qualified doctors under careful consideration of risks and facial anatomy.

Pyoderma gangrenosum following reduction mammoplasty: Systematic review of the literature and case report.

BACKGROUND: Pyoderma gangrenosum (PG) is a rare inflammatory neutrophilic dermatosis that can develop at a surgical site. Diagnosis can be challenging at its presentation causing delays in appropriate treatment. The aim of this study is to review the current literature as well as to describe the clinical presentation, diagnostic pathway, and treatment of PG after reduction mammaplasty in order to define a standardized multidisciplinary diagnostic and therapeutic approach. In the future, this may ease early identification and prompt treatment, and eventually minimize severe morbidity and long-term sequelae. METHODS: The entire PubMed/Medline database was screened following the PRISMA guidelines to identify studies describing PG that have occurred after reduction mammoplasty. RESULTS: Twenty-eight articles including 31 patients reported a PG after breast reduction surgery between January 1988 and March 2022. Twenty-one (68%) patients presented with skin ulcerations, 14 (45%) with erythema, and 5 (16%) with vesicles. Out of the 30 cases that underwent bilateral surgery, 18 (60%) developed PG bilaterally. In 12 out of 31 patients, nipple-areolar complex (NAC) involvement was evaluated, though in 10 patients (83%) the NAC was spared. Of the 20 patients (65%) who underwent skin biopsies for histopathological examination, 18 (90%) showed neutrophilic infiltration of the dermal layers. All 31 patients (100%) showed rapid clinical improvement after the introduction of immunosuppressive therapy. CONCLUSIONS: PG can result in devastating skin alterations also after reduction mammoplasty, if misdiagnosed. However, it presents with constant yet unspecific local and general signs and symptoms that can be recognized to early initiate an appropriate pharmacological treatment.

Caloric Restriction: A Novel Conditioning Strategy to Improve the Survival of Ischemically Challenged Musculocutaneous Random Pattern Flaps.

Caloric restriction (CR) is a cost-effective and easy-to-perform approach to counteracting surgical stress. The present study therefore evaluates the tissue-protective effects of a 30% CR in musculocutaneous flaps undergoing ischemia. For this purpose, a well-established murine dorsal skinfold chamber model, in combination with random pattern musculocutaneous flaps, was used. C57BL/6N mice were divided at random into a CR group (n = 8) and a control group with unrestricted access to standard chow (n = 8). The CR animals were subjected to a 30% reduction in caloric intake for 10 days before flap elevation. Intravital fluorescence microscopy was carried out on days 1, 3, 5, 7 and 10 after flap elevation to assess the nutritive blood perfusion, angiogenesis and flap necrosis. Subsequently, the flap tissue was harvested for additional histological and immunohistochemical analyses. The CR-treated animals exhibited a significantly higher functional capillary density and more newly formed microvessels within the flap tissue when compared to the controls; this was associated with a significantly higher flap survival rate. Immunohistochemical analyses showed a decreased invasion of myeloperoxidase-positive neutrophilic granulocytes into the flap tissue of the CR-treated mice. Moreover, the detection of cleaved caspase-3 revealed fewer cells undergoing apoptosis in the transition zone between the vital and necrotic tissue in the flaps of the CR-treated mice. These results demonstrate that a CR of 30% effectively prevents flap necrosis by maintaining microperfusion on a capillary level and inhibiting inflammation under ischemic stress. Hence, CR represents a promising novel conditioning strategy for improving the survival of musculocutaneous flaps with random pattern perfusion.

MRI-Conditional Breast Tissue Expander: First In-Human Multi-Case Assessment of MRI-Related Complications and Image Quality.

This study aims to assess potential complications and effects on the magnetic resonance imaging (MRI) image quality of a new MRI-conditional breast tissue expander (Motiva Flora®) in its first in-human multi-case application. Twenty-four patients with 36 expanders underwent non-contrast breast MRI with T1-weighted, T2-weighted, and diffusion-weighted imaging (DWI) sequences on a 3 T unit before breast tissue expander exchange surgery, being monitored during and after MRI for potential complications. Three board-certified breast radiologists blindly and independently reviewed image quality using a four-level scale ("poor", "sufficient", "good", and "excellent"), with inter-reader reliability being assessed with Kendall's τb. The maximum diameters of RFID-related artifacts on T1-weighted and DWI sequences were compared with the Wilcoxon signed-rank test. All 24 examinations were completed without patient-related or device-related complications. The T1-weighted and T2-weighted sequences of all the examinations had "excellent" image quality and a median 11 mm (IQR 9-12 mm) RFID artifact maximum diameter, significantly lower (p < 0.001) than on the DWI images (median 32.5 mm, IQR 28.5-34.5 mm). DWI quality was rated at least "good" in 63% of the examinations, with strong inter-reader reliability (Kendall's τb 0.837, 95% CI 0.687-0.952). This first in-human study confirms the MRI-conditional profile of this new expander, which does not affect the image quality of T1-weighted and T2-weighted sequences and moderately affects DWI quality.

Uncertainties and controversies in axillary management of patients with breast cancer.

The aims of this Oncoplastic Breast Consortium and European Breast Cancer Research Association of Surgical Trialists initiative were to identify uncertainties and controversies in axillary management of early breast cancer and to recommend appropriate strategies to address them. By use of Delphi methods, 15 questions were prioritized by more than 250 breast surgeons, patient advocates and radiation oncologists from 60 countries. Subsequently, a global virtual consensus panel considered available data, ongoing studies and resource utilization. It agreed that research should no longer be prioritized for standardization of axillary imaging, de-escalation of axillary surgery in node-positive cancer and risk evaluation of modern surgery and radiotherapy. Instead, expert consensus recommendations for clinical practice should be based on current evidence and updated once results from ongoing studies become available. Research on de-escalation of radiotherapy and identification of the most relevant endpoints in axillary management should encompass a meta-analysis to identify knowledge gaps, followed by a Delphi process to prioritize and a consensus conference to refine recommendations for specific trial designs. Finally, treatment of residual nodal disease after surgery was recommended to be assessed in a prospective register.

Microvascular Fragments Protect Ischemic Musculocutaneous Flap Tissue from Necrosis by Improving Nutritive Tissue Perfusion and Suppressing Apoptosis.

Microvascular fragments (MVF) derived from enzymatically digested adipose tissue are functional vessel segments that have been shown to increase the survival rate of surgical flaps. However, the underlying mechanisms have not been clarified so far. To achieve this, we raised random-pattern musculocutaneous flaps on the back of wild-type mice and mounted them into dorsal skinfold chambers. The flaps were injected with MVF that were freshly isolated from green fluorescent protein-positive (GFP+) donor mice or saline solution (control). On days 1, 3, 5, 7, and 10 after surgery, intravital fluorescence microscopy was performed for the quantitative assessment of angiogenesis, nutritive blood perfusion, and flap necrosis. Subsequently, the flaps were analyzed by histology and immunohistochemistry. The injection of MVF reduced necrosis of the ischemic flap tissue by ~20%. When compared to controls, MVF-injected flaps also displayed a significantly higher functional capillary density and number of newly formed microvessels in the transition zone, where vital tissue bordered on necrotic tissue. Immunohistochemical analyses revealed a markedly lower number of cleaved caspase-3+ apoptotic cells in the transition zone of MVF-injected flaps and a significantly increased number of CD31+ microvessels in both the flaps' base and transition zone. Up to ~10% of these microvessels were GFP+, proving their origin from injected MVF. These findings demonstrate that MVF reduce flap necrosis by increasing angiogenesis, improving nutritive tissue perfusion, and suppressing apoptosis. Hence, the injection of MVF may represent a promising strategy to reduce ischemia-induced flap necrosis in future clinical practice.

Fatter Is Better: Boosting the Vascularization of Adipose Tissue Grafts.

Adipose tissue resorption after fat grafting is a major drawback in plastic and reconstructive surgery, which is primarily caused by the insufficient blood perfusion of the grafts in the initial phase after transplantation. To overcome this problem, several promising strategies to boost the vascularization and, thus, increase survival rates of fat grafts have been developed in preclinical studies in recent years. These include the angiogenic stimulation of the grafts by growth factors and botulinum neurotoxin A, biologically active gels, and cellular enrichment, as well as the physical and pharmacological stimulation of the transplantation site. To transfer these approaches into future clinical practice, it will be necessary to establish standardized procedures for their safe application in humans. If this succeeds, the surgical outcomes of fat grafting may be markedly improved, resulting in a significant reduction of the physical and psychological stress for the patients.

Perioperative Intermittent Fasting Protects Ischemic Musculocutaneous Flap Tissue from Necrosis.

BACKGROUND: Dietary restriction, such as intermittent fasting (IF), has previously been shown to protect various tissues from ischemia-induced necrosis. Based on this finding, the authors herein evaluated for the first time the tissue-protective effects of IF in musculocutaneous flaps. METHODS: Male C57BL/6N mice were randomly assigned to an IF group ( n = 8) and a control group with unrestricted access to standard diet ( n = 8). IF animals were put on a perioperative feeding schedule with 8 hours of unrestricted access to standard diet per day starting 7 days before flap elevation up to 3 days after surgery. Random pattern musculocutaneous flaps were raised and mounted into a dorsal skinfold chamber. Intravital fluorescence microscopy was performed on days 1, 3, 5, 7, and 10 after surgery for the quantitative assessment of angiogenesis, nutritive blood perfusion, and flap necrosis. After the in vivo observation period, the flaps were harvested for additional histologic and immunohistochemical analyses. RESULTS: The authors found that the IF group exhibited more newly formed microvessels and a higher functional capillary density within the flap tissue when compared with controls. This was associated with a significantly lower rate of tissue necrosis. Immunohistochemical detection of different inflammatory cell subtypes revealed a markedly reduced number of invading myeloperoxidase-positive neutrophilic granulocytes in the musculocutaneous tissue of IF-treated animals. CONCLUSION: Considered together, these findings indicate that IF prevents flap necrosis by maintaining nutritive tissue perfusion and suppressing ischemia-induced inflammation. CLINICAL RELEVANCE STATEMENT: Given the frequent use of flaps in plastic surgery and the high rates of ischemic complications, any new approach to decrease such complications is clinically relevant.

Effects of negative pressure wound therapy with instillation and dwell time (NPWTi-d) versus NPWT or standard of care in orthoplastic surgery: A systematic review and meta-analysis.

Negative pressure wound therapy (NPWT) is a wound-dressing system that applies sub-atmospheric pressure on the surface of a wound to promote healing. An evolution of this technology, NPWT with solution instillation and dwell time (NPWTi-d), is increasingly being used to maximise wound closure and reduce failure rates. However, there is still a lack of evidence concerning its use in orthoplastic surgery. Therefore, the aim of this study is to compare NPWTi-d with NPWT and standard of care for wound management in orthoplastic surgery. A comprehensive literature search using PubMed, Web of Science, and Cochrane databases up to 15 March 2022 was performed, including studies describing the outcomes of NPWTi-d for traumatic/orthopaedic injuries. A meta-analysis on the number of surgical debridements, as well as the rate of complete wound closure and complications was carried out, although for other outcomes, a descriptive statistic was applied. Risk of bias and quality of evidence were assessed using the Downs& Black's Checklist for Measuring Quality. Thirteen studies with a total number of 871 patients were included, in which NPWTi-d demonstrated significantly higher primary wound closure and lower complication rates (P < .05). No difference in the number of surgical procedures required for final wound healing was observed. Moreover, five out of six studies showed better results for NPWTi-d when the change of the bioburden and bacterial count of the wound were analysed. A singular study investigating the length of the hospital stay of patients treated with NPWTi-d showed a reduction in the latter. The present meta-analysis proves that NPWTi-d is superior to NPTW or conventional dressings in orthoplastic wound care management, in terms of complete wound closure rate and the reduced number of complications. Still, the limited quality of the studies analysed shows that future randomised studies are needed to confirm the benefits and to identify the most appropriate recommendations for using NPWTi-d in orthoplastic surgery, as well as to investigate the cost-effectiveness of this wound-dressing system.

[New Technologies in Microsurgery: Potential, Indications and Economical Aspects - Report of the Consensus Workshop of the German-Speaking Society for Microsurgery of Peripheral Nerves and Vessels (DAM)]. / Neue Technologien in der Mikrochirurgie: Potential, Indikationen und ökonomische Aspekte ­ Konsensus-Bericht der Deutschsprachigen Arbeitsgemeinschaft für Mikrochirurgie der peripheren Nerven und Gefäße (DAM).

Recently, several new technologies to support microsurgeons have received European market approval. This article summarizes and discusses the impressions of an expert panel to classify the potential of new technologies in terms of benefits for the surgeon, specific indications and economic aspects during the 42nd Annual Meeting of the German-speaking Working Group for Microsurgery of Peripheral Nerves and Vessels (DAM) in Graz, Austria. In general, the expert panel addressed the principles and prerequisite for the successful establishment of new technologies and, in particular, novel optical and robotic systems. For this purpose, the current scientific literature was reviewed and initial clinical experience in the context of case series and retrospective studies was presented by the members of the expert panel. In the ensuing discussion, it was pointed out that it will first be necessary to identify patient subgroups in which the use of the new technologies is most likely to achieve a clinical benefit. Since clinical approval has already been granted for some systems, an approach can be developed for immediate clinical application from the simplest possible use to ever finer applications, i. e. from microsurgery to supermicrosurgery. Initially, funding for cost-intensive systems would presumably not be possible through revenue from standard care, but only through grants or subsidized clinical trials. In a final survey, the majority of meeting participants see the need for a price reduction of both visualization and surgical robotics technologies to enable widespread clinical establishment. Likewise, a majority of participants would prefer a combination of an exoscope or robotic microscope and a surgical robot for clinical use. The present consensus work addresses the development of a strategy for the effective establishment of new technologies, which should further increase the surgical quality of selected interventions.

[The Value of Synthetic and Biologic Meshes in Implant-Based Breast Reconstruction]. / Der Stellenwert von synthetischen Netzen und biologischen Matrices in der Implantat-basierten Brustrekonstruktion.

Implant based breast reconstruction (IBBR) keeps evolving and has been influenced heavily by the use of synthetic and biologic meshes in the last years. In both, subpectoral as well as prepectoral approaches the use of synthetic and biologic meshes has made it possible to place implants precisely according to the breast's footprint and strengthen soft-tissue coverage, particularly in the lower pole of the breast with lower complication rates and better cosmesis. Various mesh options that differ in material, processing, size and cost are currently in clinical use. This review aims to define the role of biologic and synthetic meshes in IBBR regarding the advantages and disadvantages of their use.

[The Significance of Oncoplastic Breast Reconstruction After Tumorectomy in Surgical Breast Cancer Therapy]. / Der Stellenwert der onkoplastischen Brustrekonstruktion nach Tumorektomie in der chirurgischen Brustkrebs-Behandlung.

Breast-conserving therapy (BCT), meaning tumorectomy in combination with systemic therapy and locoregional radiation therapy has become the preferred method to treat early-stage breast cancer. With excellent long-term recurrence-free and overall survival rates, breast surgeons today must deliver du- rable and aesthetically appealing results that guarantee a good quality of life to meet the high patient expectations. Oncoplas- tic breast surgery (OPBS) is an innovative approach to improve the overall results of BCT. Often carried out by a team of a plastic surgeon and an oncologic breast surgeon, OPBS can actively prevent breast deformities without compromising oncological safety. In the following, an overview of the principles and techniques of oncoplastic breast surgery will be given due to its ever-increasing significance and its advantages and dis- advantages will be discussed in the context of reconstructive breast surgery.

Generation of Cross-Specialty Consensus Statements on Soft Tissue Management via a Modified Delphi Method.

BACKGROUND: Soft tissue management (STM) training programs for surgeons are largely tradition based, and substantial differences exist among different surgical specialties. The lack of comprehensive and systematic clinical evidence on how surgical techniques and implants affect soft tissue healing makes it difficult to develop evidence-based curricula. As a curriculum development group (CDG), we set out to find common grounds in the form of a set of consensus statements to serve as the basis for surgical soft tissue education. METHODS: Following a backward planning process and Kern's six-step approach, the group selected 13 topics to build a cross-specialty STM curriculum. A set of statements based on the curriculum topics were generated by the CDG through discussions and a literature review of three topics. A modified Delphi process including one round of pilot voting through a face-to-face CDG meeting and two rounds of web-based survey involving 22 panelists were utilized for the generation of consensus statements. RESULTS: Seventy-one statements were evaluated, and 56 statements reached the 80% consensus for "can be taught as is." CONCLUSIONS: Using a modified Delphi method, a set of cross-specialty consensus statements on soft tissue management were generated. These consensus statements can be used as a foundation for multi-specialty surgical education. Similar methods that combine expert experience and clinical evidence can be used to develop specialty-specific consensus on soft tissue handling.

Implant-Based Breast Reconstruction after Mastectomy, from the Subpectoral to the Prepectoral Approach: An Evidence-Based Change of Mind?

Over the last years, prepectoral implant-based breast reconstruction has undergone a renaissance due to several technical advancements regarding mastectomy techniques and surgical approaches for the placement and soft tissue coverage of silicone implants. Initially abandoned due to the high incidence of complications, such as capsular contraction, implant extrusion, and poor aesthetic outcome, the effective prevention of these types of complications led to the prepectoral technique coming back in style for the ease of implant placement and the conservation of the pectoralis muscle function. Additional advantages such as a decrease of postoperative pain, animation deformity, and operative time contribute to the steady gain in popularity. This review aims to summarize the factors influencing the trend towards prepectoral implant-based breast reconstruction and to discuss the challenges and prospects related to this operative approach.

Bromelain Protects Critically Perfused Musculocutaneous Flap Tissue from Necrosis.

Bromelain has previously been shown to prevent ischemia-induced necrosis in different types of tissues. In the present study, we, therefore, evaluated for the first time, the tissue-protective effects of bromelain in musculocutaneous flaps in mice. Adult C57BL/6N mice were randomly assigned to a bromelain treatment group and a control group. The animals were treated daily with intraperitoneal injections of 20 mg/kg bromelain or saline (control), starting 1 h before the flap elevation throughout a 10-day observation period. The random-pattern musculocutaneous flaps were raised on the backs of the animals and mounted into a dorsal skinfold chamber. Angiogenesis, nutritive blood perfusion and flap necrosis were quantitatively analyzed by means of repeated intravital fluorescence microscopy over 10 days after surgery. After the last microscopy, the flaps were harvested for additional histological and immunohistochemical analyses. Bromelain reduced necrosis of the critically perfused flap tissue by ~25%. The bromelain-treated flaps also exhibited a significantly higher functional microvessel density and an elevated formation of newly developed microvessels in the transition zone between the vital and necrotic tissues when compared to the controls. Immunohistochemical analyses demonstrated a markedly lower invasion of the myeloperoxidase-positive neutrophilic granulocytes and a significantly reduced number of cleaved caspase 3-positive apoptotic cells in the transition zone of bromelain-treated musculocutaneous flaps. These findings indicate that bromelain prevents flap necrosis by maintaining nutritive tissue perfusion and by suppressing ischemia-induced inflammation and apoptosis. Hence, bromelain may represent a promising compound to prevent ischemia-induced flap necrosis in clinical practice.