Goals/Purpose:
The unpredictability of fat graft (FG) take leads surgeons worldwide to develop different technical features to achieve more predictable results. About the harvesting procedure, the “best” donor areas are generally identified as the ones with more compact fat, such us outer thigh and inner knees. The attention is also focused on the cellular trauma produced during harvesting. However, the level of harvesting has never been a matter of interest, being generally the lamellar adipose layer (i.e. fat below superficialis fascia).
Recent advances have demonstrated that FG should be conceived as an in-vivo tissue engineering procedure, where the intrinsic dynamics between the two main cell actors (adipocytes and adipose-derived stromal cells (ASCs)) support proliferation and differentiation of the stromal vascular fraction (SVF) into differentiated adipocytes.
So far, by transplanting fat with higher SVF:adipocyte ratio would lead to an improvement of the FG take. By a careful histoarchitectural analysis, the adipose tissue can be differentiated into two main layers, the superficial (i.e. subdermal or “areolar”) and the deep (i.e. “lamellar” or below superficialis fascia) layers. The superficial fat is the “true” structural fat. It is more fibrous and not much influenced by the metabolism. Here the adypocites are niched in well defined and very sepimented areolar stromal structures, with a high SVF:adipocyte ratio. The “lamellar” fat is the one influenced by metabolism. Here the adipocytes stromal niches are less defined with a corresponding low SVF:adipocyte ratio. By harvesting adipose tissue with a higher SVF:adipocyte ratio, it is possible to transplant a natural ASC-enhanced adipose tissue, without sophisticated tissue manipulation. In this paper, we report our clinical experience on eight patients undergoing cosmetic breast augmentation using both superficial and deep fat along with our preliminary in-vitro observations.
Methods/Technique:
Patients series: Between March 2012 and November 2012, eight women with hypomastia and/or breast asymmetry underwent breast augmentation with superficial and deep FG . The mean age of the patients was 26.5 years old (range 17 to 35). All patient were of normal weight, healthy and no one did smoke. The aesthetic outcomes were evaluated separately by a blinded group of plastic surgeons as well as by the attending surgeon using our standard evaluation method. The BREAST-Q data templates and scoring software, Q-score, were used to study the impact and effectiveness of breast surgery from the patient's perspective.
Surgical technique: The adipose tissue is harvested from the flanks, outer and inner thighs and medial aspect of knees. The defined area is infiltrated according to the super-wet technique. The superficial adipose tissue is aspirated using a three-holed Mercedes-type custom-made cannula (2 mm in the outer diameter, patent pending) attached to an in-line system. This cannula allows: a) to harvest a “more staminal” fat tissue than the one from the lamellar fat layer (see experimental study); b) to harvest fat even in slim patients by precisely removing small depots of fat tissue; c) to harvest more fractionated fat particles, which results in easy transplanting; d) to favour skin retraction, thus transforming the simple “harvest” in an aesthetic superficial liposuction procedure; d) to produce less trauma, thus faster recovery of the donor sites. The deep fat is aspirated with a 2.5 mm two-hole cannula. Fat is aspirated by connecting an “in line” sterile reservoir to a standard vacuum machine, set at 500 mmHg vacuum. Then lipoaspirate is transferred into 10 ml Luer-Lok syringes and spun at 3000 rpm for 2.5 minutes. After discarding the superior layer (oil) and the inferior layer (crystalloids), the middle layer consisting of purified lipoaspirate is transferred to 3-ml syringes. FG is performed multidirectionally, in the peri-glandular and intra-muscular (Pectoralis Major muscle) spaces according to Coleman technique.
Experimental study: We are evaluating in-vitro the differences in quantity and quality of the SVF between the fresh lipoaspirate harvested from areolar and lamellar fat layer by cytofluorimetry, RNA extraction and immunofluorescence from inner knees, outer thigh and abdomen. The preliminary results shows that the areolar fat layer presents an higher SVF:adypocites ratio when compared to the lamellar layer.
Results/Complications:
The average FG volume per session have been of 167 cc. (range 153 to 180 cc) Patient satisfaction was very high as well as surgeons' satisfaction both for the breast augmentation and for improved body contour. Clinically, the FG take was around 90%, with a follow-up up to 6 months. (Figure) No complications have been experienced.
Conclusion:
From our encouraging preliminary clinical and in-vitro observation, superficial micro fat harvesting for breast macro FG sessions allows to transfer a natural ASCs-enhanced fat and at the same time to obtain the advantages of superficial lipoplasty. This approach expands the indication for fat grafting even to slim patients with small to very small fat depots. This may represent a true full-body lipo-contouring surgery.
