Injectable Tissue Replacement and Regeneration: Anatomic Fat Grafting to Restore Decayed Facial Tissues

Effects of Nanofat in Plastic and Reconstructive Surgery: A Systematic Review

BACKGROUND

Since nanofat was first introduced by Tonnard in 2013, numerous studies have reported positive findings with its use; however, concerns exist regarding its effects and mechanisms, and the various methods used to generate nanofat also remain unclear. The authors conducted a systematic review to evaluate the efficacy of nanofat grafting alone in plastic and reconstructive surgery.

METHODS

The MEDLINE, Embase, Cochrane Central, Web of Science, and Scopus databases were searched for studies related to the use of nanofat grafting alone in plastic and reconstructive surgery. Outcomes of interest were all clinical results in humans or animals.

RESULTS

Twelve studies were included. No meta-analysis was conducted due to the clinical heterogeneity of the studies. In general, included studies had a low level of evidence. Six studies ( n = 253 patients) showed significant improvements in scar characteristics based on Patient and Observer Scar Assessment Scale, FACE-Q scale, physician assessment, patient satisfaction, and Vancouver Scar Scale scores. Four studies described the benefits of nanofat in skin rejuvenation (wrinkles, fine rhytides, pigmentation, and discoloration) through photographs, questionnaires, and indentation indices. Histologic evaluation illustrated overall increases in skin thickness, collagen, and elastic fibers. Three experimental studies showed the beneficial effects of nanofat on fat grafting, diabetic wound healing, and hair growth, with compelling histological evidence. No severe complication was reported.

CONCLUSIONS

Nanofat grafting shows potential benefits in scar and antiaging treatments, with conclusive histological evidence. Clinical studies of fat grafting, wound healing, and hair growth should be conducted, based on the results of this systematic review. Nanofat grafting could be a practical and safe procedure.

Technical Precision with Autologous Fat Grafting for Facial Rejuvenation: A Review of the Evolving Science

SUMMARY

The scientific study of facial aging has transformed modern facial rejuvenation. As people age, fat loss in specific fat compartments is a major contributor to structural aging of the face. Autologous fat grafting is safe, abundant, readily available, and completely biocompatible, which makes it the preferred soft-tissue filler in the correction of facial atrophy. The addition of volume through fat grafting gives an aging face a more youthful, healthy, and aesthetic appearance. Harvesting and preparation with different cannula sizes and filter-cartridge techniques have allowed for fat grafts to be divided based on parcel size and cell type into three major subtypes: macrofat, microfat, and nanofat. Macrofat and microfat have the benefit of providing volume to restore areas of facial deflation and atrophy in addition to improving skin quality; nanofat has been shown to improve skin texture and pigmentation. In this article, the authors discuss the current opinions regarding fat grafting and how the evolving science of fat grafting has led to the clinical utility of each type of fat to optimize facial rejuvenation. The opportunity exists to individualize the use of autologous fat grafting with the various subtypes of fat for the targeted correction of aging in different anatomic areas of the face. Fat grafting has become a powerful tool that has revolutionized facial rejuvenation, and developing precise, individualized plans for autologous fat grafting for each patient is an important advancement in the evolution of facial rejuvenation.

Low Negative Pressure Combined With Supertumescence Microliposuction as a New Method for Repairing Facial Fat Overfilling: A Case Series of 32 Patients

BACKGROUND

Face fat overfilling sometimes occurs and is unfortunately very difficult to repair.

OBJECTIVES

The aim of this study was to report initial experience of microliposuction with low negative pressure combined with supertumescence (LNPST) in a case series of 32 patients.

METHODS

The LNPST microliposuction was performed in 32 patients aged 22 to 41 years (mean [standard deviation] age, 29.6 [4.9] years) with facial overfilling. Discomfort and bleeding were monitored intraoperatively by 2 independent plastic surgeons, who used a grading system to record the results. All patients were followed-up for hematoma within 1 week postoperatively and for skin numbness and muscle paralysis at 1 week and 3 months postoperatively. In addition, at 6 months postoperatively, patient satisfaction with the postoperative aesthetic effects was analyzed by FACE-Q questionnaire.

RESULTS

All patients successfully completed the operation under local anesthesia. The mean intraoperative discomfort and blood-loss scores were 1.69 [0.62] and 1.22 [0.41], respectively. The hematoma score was 1.13 [0.34] within 1 week. Other scores included postoperative skin numbness (1 week, 1.96 [0.62]; 3 months, 1.13 [0.33]) and postoperative muscle paralysis (1 week, 1.22 [0.51]; 3 months, 1.0 [0]). Overall, neither skin necrosis nor serious complications requiring revision surgery occurred. Seventy-two percent of the patients (n = 23) answered the FACE-Q questionnaire and the score was 21.8 (1.7), covering satisfaction with the outcome score into a standard score (81.7 [15.1], from 0 to 100), which verified the high satisfaction rate.

CONCLUSIONS

LNPST technology is a safe and effective method for repair of facial fat overfilling, with less bleeding, less nerve injury, fewer complications, and high patient satisfaction.

LEVEL OF EVIDENCE: 4

Indication-based protocols with different solutions for mechanical stromal-cell transfer

Background

Regenerative medicine is the fastest developing branch of plastic surgery in recent times. Adipose tissue is one of the largest and most important sources in the body for stromal cells. Although mechanical isolation methods are both very popular and have many advantages, they still have no accepted protocols.

Objective

We developed new protocols called indication-based protocols (IPs) for standardization and new techniques called mechanical stromal-cell transfer (MEST) by using ultra-sharp blades and dilution of adipose tissue with different solutions (saline, Ringer and 5% Dextrose)

Methods & material: In order to obtain the desired physical structure (liquid, gel, solid) and the desired volume, four different types of IPs have been defined. Adipose tissue was prediluted with different solutions using 10 or 20 cc injectors in IPs 1 and 2, while condensed adipose tissue was used directly in IPs 3 and 4.

Results

In MEST, stromal cells were obtained from 100 mL of condensed fat using different IPs with 92% mean viability and cell counts of 26.80–91.90 × 10⁶. Stromal cells can be obtained in the desired form and number of cells by using four different IPs.

Conclusion

Isolation of stromal cells by cutting fat with sharp blades will prevent the death of fat tissue and stromal cells and will allow high viability and cell count with our new technique. Predilution with different solutions: Diluting the condensed adipose tissue with the desired solutions (saline, Ringer or 5% Dextrose) before the adinizing process will provide even more stromal cells.

Lay Summary

Obtaining regenerative stromal cells from adipose tissue can be done by two methods: Enzymatic and mechanical. Mechanical methods have many advantages. Although mechanical stromal cell extraction from adipose tissue is very popular and many techniques have been described, there are still no accepted protocols, definition for the end product, and no consensus on the status of the stromal cells. In this study, stromal cells were obtained mechanically by using ultra-sharp blade systems, without exposing adipose tissue to blunt trauma. Thus, a higher number of cells and higher viability could be obtained. An “Indication based” protocol has been defined for the first time in order to obtain the desired number and status (solid, semi-solid, liquid)

end product. Diluting the condensed adipose tissue with the desired solutions (saline, Ringer or 5% Dextrose) before the adinizing process will provide even more stromal cells. This will provide an opportunity for clinicians to obtain and apply a stromal cell solution for different indications in different anatomical regions.

Translational products of adipose tissue-derived mesenchymal stem cells: Bench to bedside applications

With developments in the field of tissue engineering and regenerative medicine, the use of biological products for the treatment of various disorders has come into the limelight among researchers and clinicians. Among all the available biological tissues, research and exploration of adipose tissue have become more robust. Adipose tissue engineering aims to develop by-products and their substitutes for their regenerative and immunomodulatory potential. The use of biodegradable scaffolds along with adipose tissue products has a major role in cellular growth, proliferation, and differentiation. Adipose tissue, apart from being the powerhouse of energy storage, also functions as the largest endocrine organ, with the release of various adipokines. The progenitor cells among the heterogeneous population in the adipose tissue are of paramount importance as they determine the capacity of regeneration of these tissues. The results of adipose-derived stem-cell assisted fat grafting to provide numerous growth factors and adipokines that improve vasculogenesis, fat graft integration, and survival within the recipient tissue and promote the regeneration of tissue are promising. Adipose tissue gives rise to various by-products upon processing. This article highlights the significance and the usage of various adipose tissue by-products, their individual characteristics, and their clinical applications.

Injectable Filler Technique for Face Lifting Based on Dissection of True Facial Ligaments

BACKGROUND

Strengthening weakened ligament tissues with injectable fillers to improve their supportive effect may achieve the aesthetic goal of face lifting.

OBJECTIVES

The aim of the study was to design an injectable technique for enhancing the true facial ligaments and dissect the ligaments to provide anatomical guidance for effective injection.

METHODS

Six true facial ligaments were chosen as target anatomical sites for injection. Specimens were dissected, and 3-dimensional (3D) images were reconstructed to confirm the exact location of each injection site and to confirm that the proposed injection routes will not cause dangerous vascular damage. A total of 5 patients received the injections; 3D images were taken before and after the injections for comparison and clinical outcome assessments.

RESULTS

The injection technique was designed to target 6 true facial ligaments, as follows. Site 1 targeted the temporal ligamentous adhesion region to lift the lateral ends of the eyebrows. Site 2 targeted the region of the lateral orbital thickening to lift the lateral canthus. Site 3 and site 4 targeted the zygomatic retaining ligaments and zygomatic cutaneous ligaments, respectively, to augment the soft tissues of the midface. Site 5 targeted the region of the maxillary ligament to lessen the nasolabial folds, and site 6 targeted the mandibular ligament to reduce the marionette line.

CONCLUSIONS

This site-specific injection technique targeting the true ligaments may lead to increased efficiency and accuracy of face rejuvenation and exert a lifting effect.

LEVEL OF EVIDENCE: 4

Facial Rejuvenation With Fat Grafting and Fillers

Facial rejuvenation requires a multi-modality approach to address the sun damage, volume loss, and thinning of skin that occurs with aging. With age, the collagen fibrils that provide strength become fragmented and fibroblasts connections become weak, leading to skin laxity and loss of youthful skin. Fillers can lead to a more youthful appearance by providing volumetric support. Synthetic fillers such as hyaluronic acid products, calcium hydroxyapatite, polylactic acid, and polymethylmethacralate have bio-stimulatory affects, ranging from small effects on fibroblast production to prolonged stimulatory effects on dermal thickness and blood supply. Fat grafting is also an ideal technique for facial rejuvenation because it is readily available, natural, and has regenerative effects. This review describes a new technique of fat grafting for the face called Injectable Tissue Replacement and Regeneration that specifically addresses the different anatomic compartments of the face with volume loss. With this brief review, we aim to evaluate the currents trends of fat grafting and fillers in the management of facial rejuvenation, including the cellular changes that occur with facial aging, the bio-stimulatory effects of fillers, and the anatomic replacement of tissue with fat grafting. >Level of Evidence: 4.

Facelift With Power-Assisted Dissection: A Preliminary Report

BACKGROUND

Subcutaneous elevation of the skin has remained a key component in all facelift techniques.

OBJECTIVES

The aim of this preliminary report was to introduce the ABC facelift as a 3-step method addressing photodamage, soft tissue laxity, and areas of bone and volume loss.

METHODS

The procedure consists of: (A) anatomic and regenerative adipose grafting prior to skin elevation; (B) the use of a Baraf elevator for takedown of perpendicular subcutaneous fibers following hydrodissection of the skin flaps with tumescent solution; and (C) cautery dissection of the superficial muscular aponeurotic system (SMAS) and platysma in the neck.

RESULTS

Thirty-four patients (31 females; 3 male), aged 50 to 77 years at the date of procedure, underwent an ABC facelift. Dissection of the skin flaps and SMAS elevation were faster than with traditional methods, averaging 10 to 15 minutes per hemiface. Bleeding was reduced (average estimated blood loss, 12 mL) and the skin flaps appeared better perfused with less venous engorgement and ecchymosis than achieved with sharp scissor dissection. In general, patients appeared to have shorter postoperative recovery courses and less social downtime secondary to bruising and edema.

CONCLUSIONS

The ABC facelift addresses facial laxity, volume loss, and skin aging with 3 simple steps: anatomic and regenerative fat grafting, combined with power-assisted dissection of the skin and cautery elevation of the SMAS. The use of more advanced hydrodissection tools to achieve further improvements in layer separation is currently being investigated.

LEVEL OF EVIDENCE: 4

Not Stromal Vascular Fraction (SVF) or Nanofat, but Total Stromal-Cells (TOST): A New Definition. Systemic Review of Mechanical Stromal-Cell Extraction Techniques

The most important and greatest source in the body for regenerative cells is fat tissue. Obtaining regenerative cells from adipose tissue can be done in two ways: Enzymatic and mechanical. The regenerative cell cocktail obtained by the enzymatic method, including stem cells, is called Stromal vascular fracture (SVF). In the literature, there is no clear definition of regenerative cells obtained by mechanical method. We systematically searched the techniques and definitions for stromal cells obtained from adipose tissue by scanning different databases. To evaluate the mechanical stromal-cell isolation techniques and end products from adipose tissue. Systematic review of English and non-English articles using Embase, PubMed, Web of Science and Google scholar databases. Search terms included Nanofat, fragmented fat, mechanical stromal / stem cell, mechanical SVF, SVF gel. We screened all peer-reviewed articles related with mechanical stromal-cell isolation. Author performed a literature query with the aforementioned key words and databases. A total of 276 publications containing the keywords we searched were reached. In these publications, there are 46 different definitions used to obtain mechanical stromal cells. The term SVF is only suitable for enzymatic methods. A different definition is required for mechanical. The most used term nanofat is also not suitable because the product is not in both "fat" and in "nanoscale". We think that the term total stromal-cells would be the most appropriate definition since both extracellular matrix and all stromal cells are protected in mechanical methods.

New Mechanical Fat Separation Technique: Adjustable Regenerative Adipose-tissue Transfer (ARAT) and Mechanical Stromal Cell Transfer (MEST)

Background

Adipose tissue is not only a very important source of filler but also the body's greatest source of regenerative cells.

Objectives

In this study, adipose tissue was cut to the desired dimensions using ultra-sharp blade systems to avoid excessive blunt pressure and applied to various anatomical areas-a procedure known as adjustable regenerative adipose-tissue transfer (ARAT). Mechanical stromal cell transfer (MEST) of regenerative cells from fat tissue was also examined.

Methods

ARAT, MEST, or a combination of these was applied in the facial area of a total of 24 patients who were followed for at least 24 months. The integrity of the fat tissue cut with different diameter blades is shown histopathologically. The number and viability of the stromal cells obtained were evaluated and secretome analyses were performed. Patient and surgeon satisfaction were assessed with a visual analog scale.

Results

With the ARAT technique, the desired size fat grafts were obtained between 4000- and 200-micron diameters and applied at varying depths to different aesthetic units of the face, and a guide was developed. In MEST, stromal cells were obtained from 100 mL of condensed fat using different indication-based protocols with 93% mean viability and cell counts of 28.66 to 88.88 × 10⁶.

Conclusions

There are 2 main complications in fat grafting: visibility in thin skin and a low retention rate. The ARAT technique can be used to prevent these 2 complications. MEST, on the other hand, obtains a high rate of fat and viable stromal cells without applying excessive blunt pressure.

Level of Evidence 4

A multi-center, open-label, pilot study of allograft adipose matrix for the correction of atrophic temples

BACKGROUND

Autologous fat grafting (AFG) and synthetic fillers are currently used in esthetic and reconstructive surgery. Challenges in AFG include inconsistent graft retention, donor site morbidities, insufficient harvest, and excessive harvesting times. An allograft adipose matrix (AAM) has been developed as an off-the-shelf alternative to AFG and synthetic fillers.

AIMS

To evaluate the clinical safety and retention of an AAM over 24 weeks after treatment of bilateral atrophic temples.

PATIENTS/METHODS

Ten subjects (nine females, one male, aged 47-69 years) with temple atrophy were enrolled in the IRB-approved study. AAM (Renuva^® , MTF Biologics, Edison, NJ) was injected (<3 mL) bilaterally into the atrophic temples of each subject. Volume retention, global improvement, and safety were evaluated at 1, 4, 8, 12, 16, 20, and 24 weeks. Biopsy specimens were obtained for adipogenic and angiogenic histological evaluation.

RESULTS

The mean temple volume improved over the baseline and was retained throughout the study period. Fullness (measure of volume) increased immediately from 0 pretreatment to 2.8 post-treatment (scale 0-4 = none-maximum). Fullness varied from 0.8 to 2.2 from weeks 1 through 12 and was 2.7-3.0 from weeks 16-24, around 75% increase from baseline. Furthermore, skin tone, smoothness, texture, and overall appearance also improved with 71% of subjects being satisfied to very satisfied with the results. Adverse events were minimal and histology revealed native tissue incorporation and remodeling.

CONCLUSION

AAM is safe and well tolerated, provides at least 6-month volume retention, improves skin quality, and supports adipose tissue remodeling after treatment into temples.

Nonsurgical jawline rejuvenation using injectable fillers

BACKGROUND

A well-defined jawline is a critical component in the perception of facial attractiveness in both men and women. Dermal fillers offer a nonsurgical, temporary method of correcting mild-to-moderate mandibular bone resorption.

AIMS

The authors discuss pertinent aspects of anatomy, pathophysiology of aging, patient evaluation, gender considerations, injection technique, and complications in jawline augmentation using injectable fillers.

METHODS

A brief review of the literature surrounding jawline augmentation using injectable fillers in both men and women, as well as the authors' experience in this area, is provided.

RESULTS

Nonsurgical jawline augmentation using injectable fillers can be performed effectively and safely with adequate background knowledge of the regional anatomy and appropriate patient selection. The authors discuss both injection techniques in the published literature and their own approach. Potential complications are also reviewed.

CONCLUSION

Jawline rejuvenation is a key component to global facial aesthetic rejuvenation. Therefore, it is important for physicians to understand how to safely and effectively perform nonsurgical jawline rejuvenation using injectable fillers.