Impact of Fat Graft Thickness and Harvesting Technique on Adipocyte Viability in a New Porcine Experimental Model: An Immunohistochemical Analysis

Reoperative Transaxillary Subfascial Breast Augmentation and Fat Grafting: Technical Highlights and a Step-by-Step Video Guide

SUMMARY

Reoperative procedures after breast augmentation are frequently more complex than primary cases because of local complications and insufficient soft-tissue coverage. Although the transaxillary incision is often indicated in primary breast augmentation, limitations of this approach include secondary surgery and correcting complications after using this approach via the same incision. Combining the transaxillary technique with a subfascial pocket has been suggested to avoid breast scarring and the limitations of submuscular pockets represented by breast animation. With advances in autogenous fat grafting (AFG) techniques, implant coverage alternatives and more natural outcomes have been reported from more superficial implant pockets. Simultaneous AFG with silicone implants (defined as hybrid breast augmentation) has been evaluated recently as an attractive procedure. These two techniques combine to provide breast projection and natural cleavage while camouflaging implant edges. AFG is also important to reduce the intermammary distance and achieve a smoother transition between the breasts. The transaxillary approach can be useful in reoperative breast augmentation and avoids additional scarring on the breast. This article and the accompanying videos provide a detailed, step-by-step guide to reoperative hybrid breast augmentation using a subfascial transaxillary approach, with a predictable and optimized surgical outcome.

Particles of Different Sizes Affect the Retention Pattern of the Fat Grafts in a Mouse Model

BACKGROUND

Autologous fat grafting is an effective form of soft tissue regeneration. However, the optimal fat particle size and graft retention pattern need more research.

METHODS

The mouse inguinal fat pad was harvested and cut into fat particles of different diameters: ≥ 5 mm, 3-4 mm, 2-3 mm, 1-2 mm and 1 mm (micro-fat). A volume of 0.2 ml fat was transplanted into another mouse dorsum. Volume and retention rate were measured at 1, 4, 8 and 12 weeks. Histology analysis was performed. Immunofluorescence staining was used to evaluate M1 and M2 macrophage infiltration and graft angiogenesis.

RESULTS

Fat retention was highest in the "> 5 mm" group and lowest in the "micro-fat" group. Large vacuoles were more common in larger-diametered fat particles. There was less collagen accumulation in the well-vascularized connective tissue in the "1-2 mm" group. The infiltrated nucleated cells peak at week 4 in groups of fat particles under 3 mm and at week 8 in in groups with fat particles above 3 mm. The number of M1 macrophages peaked at week 1 and then declined in all groups except for the "5 mm" group. The number of M2 macrophages peaked at week 4 and gradually decreased through 12 weeks in the groups below 3 mm, but increased through 12 weeks in the groups above 3 mm. Vascular intensity was similar to M2 macrophage prevalence.

CONCLUSIONS

Fat particles of different sizes may posses different retention patterns. Larger grafts have higher retention rate but worse quality. Meanwhile, smaller grafts have better quality with lower retention rate.

NO LEVEL ASSIGNED

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A Preliminary Exploratory Study of Autologous Fat Transplantation in Breast Augmentation With Different Fat Transplantation Planes

Background

Autologous fat transfer is common in breast augmentationor reconstruction. However, AFG recipient site in the breast for fat grafting has not been carefully investigated.

Methods

Forty female patients requiring breast augmentation with fat grafting were randomly assigned into two groups. The retromammary group received 2/3 fat into the retromammary space and the other 1/3 into the subcutaneous and retropectoral planes. The retropectoral group received 2/3 fat into the retropectoral plane and the other 1/3 into the subcutaneous and retromammary planes. The fat grafting result at 6 months was assessed by 3D laser surface scanning and then ultrasound. Any complications were recorded during follow-up. Samples from a patient who underwent fat grafting for 6 months was obtained and histological examination was conducted.

Results

No significant difference in the retention rate after 6 months was observed between the two groups (retromammary group: 35.9% ± 6.6; retropectoral group: 39.3% ± 5.1, p = 0.1076). The retromammary grouphad a higher incidence of oil cyst formation than the retropectoral group. Histological examination showed that there were more oil cysts and mac2 positive macrophage infiltration in the fat cells in retromammary group, while retropectoral group had more small-size adipocytes.

Conclusion

Although fat grafting into the retropectoral plane did not provide a superior fat graft retention rate, it did lower the incidence of complications. The retropectoral space show great potential to become a favorable recipient site.