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Background Fat grafting is an effective procedure for breast augmentation, but the variations in this technique result in unpredictable fat retention. Therefore, animal models are needed to simulate the operation and the optimal layer for fat retention. Objectives An autologous fat grafting murine model for breast augmentation was built to detect a new layer for fat grafting in the chest. Methods The left side of the female rat inguinal fat flap was harvested, dissected into small pieces, and autotransplanted into 3 different layers of the breast. Retention rate and hematoxylin and eosin (H&E) staining were measured at 1, 4, 8 12, and 16 weeks. Immunofluorescence staining was utilized to detect adipocytes and endothelial cells, and immunohistochemistry was conducted to evaluate the expression of integrins β1 and α6. Results The volume of fat grafts slightly grew in the intramuscular and submuscular layers at Week 4. Retention rates in the subcutaneous layer and submuscular layer were significantly higher than the intramuscular layer at Week 16. H&E staining showed that oil cysts existed in the subcutaneous layer throughout the 16 weeks. At the terminal time point, well-vascularized mature adipose structures were observed in intramuscular and submuscular layers, with smaller adipocytes in intramuscular layers. Immunohistochemistry analysis showed that integrin β1 was identically expressed in every adipocyte in all the layers, whereas integrin α6 selectively expressed in bigger adipocytes in the intramuscular layer. The expression intensities of integrin β1 and α6 were significantly higher in the intramuscular layer than in the subcutaneous and submuscular layers. Conclusions The angiogenic and moderate mechanical environment makes the submuscular layer the optimal layer for fat retention. [ABSTRACT FROM AUTHOR]

Background Dorsal augmentation with costal cartilage is generally used for aesthetic rhinoplasty. However, the tendency of costal cartilage to warp may jeopardize the aesthetic outcome. Objectives The aim of this study was to describe a new "Z" technique to overcome the warping of costal cartilage after implantation and to evaluate the efficacy of this technique in vitro. Methods A total of 31 pairs of porcine costal cartilage grafts (40 mm × 10 mm × 5 mm) were obtained and kept in Dulbecco's Modified Eagle Medium (Sigma-Aldrich, St. Louis, MO) to maintain cell viability. Paired grafts were obtained and randomly allocated for preparation by the accordion technique and the "Z" technique. Standardized photographs (obtained immediately after operation and at 4 weeks) were used for warping analysis. Biomechanical testing was performed to measure the graft's capacity to resist deformation by an external force. Results Cell viability of the grafts at 4 weeks was comparably good in the accordion group and the Z group (61.88% ± 4.47% vs 67.48% ± 7.03%, P = 0.55). Warping angle was comparable between the 2 groups (P > 0.01). The capacity to resist external force was significantly better in the Z group; the force needed to cause deformation was 3.98 ± 1.04 N in the Z group vs 1.61 ± 0.47 N in the accordion group in lateral view (P < 0.0001), and 1.33 ± 0.41 N vs 0.96 ± 0.24 N, respectively, in frontal view (P = 0.0013). Conclusions The "Z" technique appears to be a simple and effective method to minimize the tendency of costal cartilage to warp after implantation. [ABSTRACT FROM AUTHOR]

Background: The septal extension graft (SEG) has become the preferred augmentation rhinoplasty technique in Asia for its superiority in correcting tip projection and rotation.Objectives: The author sought to build a rabbit model for SEG surgery and compared the postoperative stability of the tip support between the bilateral batten costal and conchal cartilage extension grafts at the nasal tip.Methods: Twenty rabbits underwent SEG surgery with either bilateral batten costal cartilage graft (Group A) or bilateral batten conchal cartilage graft (Group B). Serial photographs were obtained to evaluate the change of the nasal tip shape and graft shape. The observed indices include tip projection, tip angle, shape of extension graft, and histological features of the extension graft.Results: Twelve weeks after the operation, one costal extension graft in group A (1/10) and three conchal extension grafts in group B (3/10) were reabsorbed. The costal cartilage graft showed better exterior results than conchal cartilage graft in terms of tip projection and angle relapse rate (13.01% vs. 25.02% and 15.18% vs. 28.73%, p < 0.05). The costal cartilage graft maintains its structure more than the conchal cartilage graft. A greater degree of calcification and more fibrous capsules around the extension graft were found in Group A.Conclusions: A rhinoplasty rabbit model was established to compare costal and conchal autologous cartilages for SEG. Additionally, this model may serve as a training tool for rhinoplasty surgeons. The costal cartilage extension graft is more reliable in terms of stability and may be paid more attention. [ABSTRACT FROM AUTHOR]