Short-term cryoprotectant-free cryopreservation at -20°C does not affect the viability and regenerative capacity of nanofat.

Nanofat is an autologous fat derivative with high regenerative activity, which is usually administered immediately after its generation by mechanical emulsification of adipose tissue. For its potential repeated use over longer time, we herein tested whether cryopreservation of nanofat is feasible. For this purpose, the inguinal fat pads of donor mice were processed to nanofat, which was i) frozen and stored in a freezer at -20°C, ii) shock frozen in liquid nitrogen with subsequent storage at -80°C or iii) gradually frozen and stored at -80°C. After 7 days, the cryopreserved nanofat samples were thawed and immunohistochemically compared with freshly generated nanofat (control). Nanofat frozen and stored at -20°C exhibited the lowest apoptotic rate and highest densities of blood and lymph vessels, which were comparable to those of control. Accordingly, nanofat cryopreserved at -20°C or control nanofat were subsequently fixed with platelet-rich plasma in full-thickness skin defects within dorsal skinfold chambers of recipient mice to assess vascularization, formation of granulation tissue and wound closure by means of stereomicroscopy, intravital fluorescence microscopy, histology and immunohistochemistry over 14 days. These analyses revealed no marked differences between the healing capacity of wounds filled with cryopreserved or control nanofat. Therefore, it can be concluded that cryopreservation of nanofat is simply feasible without affecting its viability and regenerative potential. This may broaden the range of future nanofat applications, which would particularly benefit from repeated administration of this autologous biological product.

Preconditioning Strategies for Improving the Outcome of Fat Grafting.

Autologous fat grafting is a common procedure in plastic, reconstructive, and aesthetic 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 pretransplantation phase to stimuli inducing endogenous protective and regenerative cellular adaptations, such as the upregulation 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.

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.

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.

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.