The Influencing Factors of Breast Morphological Changes After Dual-Plane Augmentation with Smooth Round Implans: A Correlational Study.

[BACKGROUND] Breast morphology is the primary objective indicator for evaluating the outcome of augmentation surgery. Studies have indicated that breast morphology undergoes certain changes during the early postoperative period, which may result in a discrepancy between postoperative outcomes and preoperative design. This study utilized three-dimensional scanning technology and statistical methods to analyze the influencing factors of breast morphology changes, aiming to provide reference for implant selection and preoperative surgical planning.

[METHODS] The study included patients who underwent endoscopic-assisted transaxillary dual-plane augmentation from July 2020 to June 2022. Anthropometry and three-dimensional scanning were performed on the enrolled patients, and the change values of postoperative breast morphological parameters were calculated. Spearman rank correlation tests were performed to assess the correlation between these changes and implant parameters as well as anthropometric measurements. Factors with high correlation were selected, and multivariate linear regression analysis was conducted.

[RESULTS] A total of 30 patients (60 breasts) were enrolled. The average downward displacement of the inframammary fold was 0.4 ± 0.3 cm, and the average outward displacement of the medial breast border was 0.2 ± 0.1 cm, both highly positively correlated with implant volume. The length of nipple-medial breast border increased by 0.5 ± 0.3 cm, highly positively correlated with the stretchability of the medial pole. The length of the nipple-to-inframammary fold increased by 0.6 ± 0.3 cm, highly positively correlated with implant volume and stretchability of the lower pole. Nipple displacement was 0.3 ± 0.2 cm outward, highly positively correlated with the stretchability of the medial pole. Nipple elevation was 0.2 ± 0.2 cm, highly positively correlated with implant volume and stretchability of the lower pole. Breast projection decreased by 0.4 ± 0.2 cm, highly positively correlated with preoperative breast projection. The average reduction in breast volume was 25.6 ± 15.7 cc, with the reduction value highly positively correlated with preoperative breast volume.

[CONCLUSIONS] After smooth round implant augmentation mammoplasty, the breasts experienced slight downward and outward displacement, with the main influencing factor being the implant volume. Nipple displacement outward and upward, as well as lateral displacement, was primarily influenced by the stretchability of the medial pole. Upward displacement was mainly influenced by implant volume and the stretchability of the lower pole. The increase in length of the nipple-to-inframammary fold skin was most significantly influenced by implant volume and the stretchability of the lower pole. Breast convexity and volume gradually decreased, with preoperative breast size having the most significant impact on these changes.

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