How Fat Grafting Works

Using 3D Bioprinted Autologous Minimally Manipulated Homologous Adipose Tissue for Limb Salvage in Treating Diabetic Foot Ulcer

Reconstructive surgeons face challenges when considering limb salvage methods for the treatment of diabetic foot ulcers (DFUs). In this article, we present our experience with autologous fat grafting as a viable alternative in cases where flap reconstruction is difficult. We encountered a 78-year-old female patient with a nonhealing DFU who had multiple comorbidities, including renal failure and severe peripheral arterial disease. During the initial multidisciplinary meeting, due to extensive necrosis and osteomyelitis, amputation was recommended. However, the patient expressed a strong preference for a salvage procedure and refused amputation. After careful consideration, we opted to reconstruct the patient's foot using three-dimensional bioprinted autologous minimally manipulated homologous adipose tissue. The AMHAT was engrafted well without complications such as autolysis, graft failure, or infection. After the operation, the large defect with partial bone exposure was covered with healthy granulation tissue. The size of the wound decreased to less than half its original size after 6 weeks of surgery, and it decreased to less than 25% after 12 weeks of surgery. The AMHAT may be an appealing treatment option for diabetic foot patients who are unsuitable for flap reconstruction due to comorbidities.

Adipose Component Transplantation: An Advanced Fat-Grafting Strategy for Facial Rejuvenation

BACKGROUND

Autologous fat grafting is frequently used for volume augmentation and tissue regeneration. The uniform physical and biological characteristics of fat grafts, however, limit their optimal effects in various situations. Subjecting fat tissue to different mechanical processes results in adipose-derived products with distinct biological components and physical features. The present study describes a novel facial fat-grafting strategy, adipose component transplantation (ACT), that yields different adipose products that can be applied to specific injection sites.

METHODS

All patients who underwent ACT were evaluated retrospectively. Fat tissue samples were fractionated into high-density fat, adipose matrix complex, stromal vascular fraction gel, and adipose collagen fragment, as described. Each of these fractions was processed and injected into indicated recipient sites. Additional SVF gel was cryopreserved and, if necessary, injected during the following 3 months. Patients were followed up after 1, 2, 3, and 6 months, and annually thereafter.

RESULTS

From March of 2020 to September of 2021, 78 patients underwent whole face fat grafting using the ACT strategy. All operations and secondary injections of cryopreserved SVF gel were uneventful. There were no major complications, and final aesthetic results were satisfactory in 91% of patients.

CONCLUSIONS

The ACT strategy allows specific adipose products to be applied to specific injection sites, as warranted. Adipose matrix complex is indicated for sufficient rigid support, high-density fat when large volumes are required, SVF gel for precise injection and cryopreservation, and ACF as mesotherapy for skin rejuvenation. The ACT strategy optimizes the biological functions and physical features of different adipose-derived products.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Fat Grafting in Vulvar Lichen Sclerosus: Long Term Follow-Up

OBJECTIVE

The rationale for the use of autologous fat grafting in the treatment of vulvar lichen sclerosus (VLS) consists in reduction of inflammation, regeneration of tissues, volume increase, and pain fiber control. The main outcome of this study was the evaluation of patients' satisfaction after treatment. Secondary outcomes included modifications in symptoms, psychosexual wellbeing, vulvar hydration, and histology after surgery.

METHODS

Eligible for this study were women aged 18-85 years with a histological diagnosis of VLS who underwent at least one autologous vulvar fat grafting at the authors' center, between 2010 and 2019. In 2021, all women underwent a clinical reevaluation, comprehensive of vulvoscopy, vulvar biopsy, and handing out of validated questionnaires.

RESULTS

Overall, 88.7% of patients declared themselves very satisfied/satisfied with the procedure. All symptoms were improved postsurgery; in particular, the difference was statistically significant for pruritus, burning, and dyspareunia ( p < .05). Sexual function was also improved at time of reevaluation, as were depressive and anxiety symptoms ( p < .05). No cases of vulvar intraepithelial neoplasia or cancer occurred during follow-up and vulvar architecture remained stable, although patients reported a significantly reduced need for topical steroids ( p < .0001). Lastly, in postoperative biopsies, inflammatory infiltrate was stable or reduced, and the distribution of elastic fibers was comparable or restored in most patients.

CONCLUSIONS

Patient satisfaction with fat grafting is detectable up to 11 years after surgery, and as such, it may represent a valid therapeutic option in selected cases of VLS.

Quantification of Fat Graft Retention in the Translabyrinthine Approach Using Magnetic Resonance Imaging Volumetric Analysis

OBJECTIVE

To characterize the viability and volume of autologous free fat grafts over time, determine clinical/patient factors that may affect free fat graft survival and assess the clinical impact of free fat graft survival on patient outcomes in the translabyrinthine approach for lateral skull base tumor resection.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary neurotologic referral center.

PATIENTS

Forty-two adult patients who underwent translabyrinthine craniotomy for resection of a lateral skull base tumor with the mastoid defect filled by autologous abdominal fat graft and subsequently underwent more than one postoperative magnetic resonance imaging (MRI) scans of the brain.

INTERVENTIONS

Mastoid obliteration with abdominal fat after craniotomy, postoperative MRI.

MAIN OUTCOME MEASURES

Rate of fat graft volume loss, fraction retention of original fat graft volume, initial fat graft volume, time to steady-state fat graft retention, rate of postoperative cerebrospinal fluid (CSF) leak, and/or pseudomeningocele formation.

RESULTS

Patients were followed postoperatively with MRI for a mean of 31.6 months with a mean of 3.2 postoperative MRIs per patient. Initial graft size was a mean of 18.7 cm3 with a steady-state fat graft retention of 35.5%. Steady-state graft retention (<5% loss per year) was achieved at a mean of 24.96 months postoperatively. No significant association was found in multivariate regression analysis of clinical factors impact on fat graft retention and CSF leak/pseudomeningocele formation.

CONCLUSIONS

In the use of autologous abdominal free fat graft for filling mastoid defects after translabyrinthine craniotomy, there is a logarithmic decline in fat graft volume over time, reaching steady state in 2 years. Rates of CSF leak or pseudomeningocele formation were not significantly affected by initial volume of the fat graft, rate of fat graft resorption, nor the fraction of original fat graft volume at steady state. In addition, no analyzed clinical factors significantly influenced fat graft retention over time.

Anti-fibrotic effect of adipose-derived stem cells on fibrotic scars

BACKGROUND

Sustained injury, through radiotherapy, burns or surgical trauma, can result in fibrosis, displaying an excessive deposition of extracellular matrix (ECM), persisting inflammatory reaction, and reduced vascularization. The increasing recognition of fibrosis as a cause for disease and mortality, and increasing use of radiotherapy causing fibrosis, stresses the importance of a decent anti-fibrotic treatment.

AIM

To obtain an in-depth understanding of the complex mechanisms underlying fibrosis, and more specifically, the potential mechanisms-of-action of adipose-derived stomal cells (ADSCs) in realizing their anti-fibrotic effect.

METHODS

A systematic review of the literature using PubMed, Embase and Web of Science was performed by two independent reviewers.

RESULTS

The injection of fat grafts into fibrotic tissue, releases ADSC into the environment. ADSCs’ capacity to directly differentiate into key cell types (e.g., ECs, fibroblasts), as well as to secrete multiple paracrine factors (e.g., hepatocyte growth factor, basis fibroblast growth factor, IL-10), allows them to alter different mechanisms underlying fibrosis in a combined approach. ADSCs favor ECM degradation by impacting the fibroblast-to-myofibroblast differentiation, favoring matrix metalloproteinases over tissue inhibitors of metalloproteinases, positively influencing collagen organization, and inhibiting the pro-fibrotic effects of transforming growth factor-β1. Furthermore, they impact elements of both the innate and adaptive immune response system, and stimulate angiogenesis on the site of injury (through secretion of pro-angiogenic cytokines like stromal cell-derived factor-1 and vascular endothelial growth factor).

CONCLUSION

This review shows that understanding the complex interactions of ECM accumulation, immune response and vascularization, is vital to fibrosis treatments’ effectiveness like fat grafting. It details how ADSCs intelligently steer this complex system in an anti-fibrotic or pro-angiogenic direction, without falling into extreme dilation or stimulation of a single aspect. Detailing this combined approach, has brought fat grafting one step closer to unlocking its full potential as a non-anecdotal treatment for fibrosis.

Plasma rich in growth factors (PRGF -ENDORET®) to rescue necrotized orbital dermis-fat grafts

PURPOSE

We report on the clinical course of three patients treated with topical plasma rich in growth factors (PRGF) to rescue dermal-fat grafts (DFG) with graft ulceration (GU).

MATERIALS AND METHODS

A retrospective, case-series study of three patients diagnosed with GU in DFG and treated with PRGF. Drops were applied four times per day and treatment was maintained until the GU resolved. Data were collected from medical records and anterior segment photos.

RESULTS

All patients showed a favorable response to topical PRGF having accomplished full resolution of the GU within a mean of 30 days of treatment (range: 21-35 days). During the full extent of follow-up, no side-effects, signs of rejection or necrosis were reported and every patient was pleased with the final aesthetic result.

CONCLUSION

Our results suggest that PRGF could be an effective treatment for dermal graft ulceration in patients who underwent DFG surgery/implantation, mainly due to its low morbidity when compared to traditional procedures.

Effects of macrophage regulation on fat grafting survival: Improvement, mechanisms, and potential application-A review

BACKGROUND

Autologous fat grafting has become a popular tool in plastic surgery to solve soft tissue defects and achieve skin rejuvenation, but the volume loss after transplantation remains a disturbing problem. In recent years, some new strategies have improved the outcome to some extent, but the fat graft retention is still far from ideal, so there remains a wide development prospect in this field. Macrophages are closely related to the local microenvironment and tissue regeneration, and their role in fat grafting has been increasingly highlighted.

AIMS

This article was aimed to review the efficacy, possible mechanisms, and potential application of macrophage regulation on fat grafting, as well as concerns and future perspectives of this filed.

METHODS

A retrospective review of the published data was conducted.

RESULTS

Most studies indicated that up-regulating M2 macrophages during fat grafting would improve fat retention via promoting neovascularization. M2 macrophages could secrete several pro-angiogenic factors, accelerate extracellular matrix (ECM) remodeling, and directly function on endothelial cells to encourage vascular expansion. In addition, macrophages could influence the proliferation, apoptosis, and adipogenic differentiation of preadipocytes.

CONCLUSIONS

During autologous fat grafting, appropriately regulating macrophages may become a promising method to increase fat retention. Nevertheless, the M2 macrophage polarizing agents, treatment opportunity, and contraindications require further discussion. We hope our work could promote more in-depth studies in this field, and we are looking forward to a standard procedure for the macrophage therapy in clinical practice.