研究背景 明确患者对乳房的审美需求是判断乳房整形手术效果能否达到患者要求和保证手术效果满意的前提条件。已有文献报道了公认的理想乳头位置、乳房对称度评价的审美标准，然而关于乳房形态这一乳房美学的重要方面，尚没有形成公认的标准，更缺乏精准的量化的研究。除了大众的审美标准，个体之间审美的差异普遍存在。为了满足不同个体需求，了解个人对乳房形态的审美倾向成为当前临床的迫切需求。但是，如何将个体对乳房形态的审美意识准确地反映为具象的、量化的三维图像一直是一个技术难题。近年来，三维扫描测量技术应用于乳房测量和分析，为获得精准的乳房三维数据创造了条件，而数据可视化技术的发展，为乳房形态的审美研究提供了技术手段。本研究应用三维扫描技术对美学评分不同的乳房形态进行测量，分析得出美学评分较高的乳房的形态特征，及相关参数的比例分布范围，进而应用数据可视化技术，还原不同比例特征的乳房三维图像，通过人群调查得到大众理想乳房形态相关参数的比例，为手术设计提供乳房审美的基本参照和客观证据；通过分析不同人群对乳房形态偏好的差异，为个性化手术提供目标和方向。 研究目的 研究一：获得不同美学评分乳房的三维数据及比例关系、特征及差异，确定影响乳房形态美学评分的关键参数及其范围，为研究美观乳房的形态特征提供基本数据。 研究二：建立将乳房比例参数转化为可视乳房三维图像的数据可视化方法，获得比例参数不同的乳房三维图像，分析大众理想的乳房形态的美学特征及比例参数，以及不同人群乳房形态审美的偏差，为手术设计提供美学标准，为个性化手术提供客观依据。 研究方法 研究一：对2016年3月至2016年6月期间前来我院的女性求美者（不限于乳房整形）进行单个乳房形态的美学自评分和整形医生评分（满分5分），平均分≥4分的乳房纳入高评分乳房组，平均分<4分的乳房纳入低评分乳房组。对乳房进行三维扫描获得前胸廓及乳房的三维模型，应用软件测量获得相关三维数据：胸骨切迹至乳头距离、乳头至中线水平距离、乳头至下皱襞垂直距离、乳房基底宽度、乳房凸度的绝对值和比例，分析高评分乳房和低评分乳房之间参数的差异，得到高评分乳房的特征及参数比例分布范围，绘制各个参数的ROC曲线，分析获得对美学评分影响较大并能较好预测美学效果的乳房径线参数，并根据灵敏度和特异度的关系找到判别乳房各径线比例参数美学评分高低的最佳临界点。 研究二：根据研究一提供的乳房参数范围，并参照已有文献报道范围，制作各径线参数规律排列的一组乳房模拟三维动态模型，其中决定乳房形态的乳房上极长度、乳头至下皱襞垂直距离、乳房凸度3个参数各设有5档变量，乳房上极饱满度设有直线型和微凸型2种类型，共生成5×5×5×2=250个乳房三维模型。请包括患者、整形医生和普通人群在内的受试者对该组250个乳房模型的动态三维图像按随机顺序分别进行美学评分，通过多因素回归分析，得到美学评分最高的乳房比例参数。引入人群特征与乳房比例参数的交互作用项，探究不同人群乳房形态审美偏好的差异。 研究结果 研究一：共收集98位患者的179例单侧乳房三维数据，其中68例乳房纳入高评分乳房组，111例乳房纳入低评分乳房组。乳房参数测量绝对值：乳房基底宽度（BW）高评分乳房组（15.0±1.4cm）与低评分乳房组（14.7±1.6cm）无显著差异（p=0.28）；胸骨切迹至乳头距离（SN-N）高评分乳房组（19.7±1.5cm）与低评分乳房组（20.5±4.0cm）无显著差异（p=0.12）；乳头至中线水平距离（N-M）高评分乳房组（9.6±0.9cm）较低评分乳房组（9.2±1.5cm）稍长（p=0.03）；乳头至下皱襞垂直距离（N-IMF）高评分乳房组（6.1±0.7cm）显著大于低评分乳房组（4.6±1.1cm）（p<0.001）；乳房凸度（BP）高评分乳房组（4.5±1.2cm）显著大于低评分乳房组（3.0±1.8cm）（p<0.001）。以乳房基底宽度的一半（BR）作为基准，各参数与BR之比：SN-N/BR高评分乳房组（2.64±0.22）较低评分乳房组（2.78±0.41）稍小（p=0.01）；N-M/BR高评分乳房组（1.29±0.11）与低评分乳房组（1.25±0.16）无显著差异（p=0.05）；N-IMF/BR高评分乳房组（0.82±0.13）显著大于低评分乳房组（0.63±0.17）（p<0.001）；BP/BR高评分乳房组（0.60±0.17）显著大于低评分乳房组（0.41±0.22）（p<0.001）。BP/BR指标的ROC曲线下面积为0.747，N-IMF/BR曲线下面积为0.815，BP/BR+N-IMF/BR曲线下面积为0.865，能够较好地判定美学评分高低，BP/BR最佳临界值为0.635，N-IMF/BR最佳临界值为0.723，BP/BR+N-IMF/BR最佳临界值为4.1×BP/BR+8.2×N-IMF/BR=8.123。 研究二：共有183位受试者完成美学偏好测试，收集到45750次乳房评分，本测试克朗巴赫系数（Cronbach's α）为0.99，结果稳定可靠。乳房上极长度与乳房横半径之比（UPL/BR）、乳头至乳房下皱襞垂直距离与乳房横半径之比（N-IMF/BR）、乳房凸度与乳房横半径之比（BP/BR）、乳房上极饱满度（UPF）均对乳房美学评分产生影响。UPF为微凸型美学评分更高。回归方程中UPL/BR、N-IMF/BR、BP/BR的二次项系数均有统计学意义，且为二次项系数为负值，回归曲线是开口找下的抛物线，乳房美学评分存在最大值，美学评分最高时N-IMF/BR值为1.05， UPL/BR值为1.15，BP/BR值为0.94。最终得出美观乳房的形态为上极微凸且满足以下比例，乳房横半径：乳头到下皱襞垂直距离：乳头到乳房上边界垂直距离：乳房凸度=1:1.05:1.15:0.94。不同年龄、BMI、性别、婚姻史、生育史、乳房手术史、职业、求美目的的受试者的理想乳房比例参数不同，乳房形态审美差异普遍存在。 研究结论 研究一：乳房基底宽度对乳房的形态的美学评分没有影响，可作为表示乳房形态比例相对固定的参考基准。不同美学评分乳房的参数中乳房凸度和乳头到下皱襞垂直距离存在显著差异，乳房凸度和乳头到下皱襞垂直距离可作为判断乳房形态美学的指标。本部分研究得到了美观乳房的形态比例参数范围，为进一步确定理想乳房的精确比例提供了依据。 研究二：建立了基于数据可视化技术的乳房美学研究方法。理想乳房上极微凸，乳房横半径：乳房上极长度：乳房下极长度：乳房凸度=1:1.15:1.05:0.94，提示理想乳房下半极接近半球形，可作为乳房整形手术设计的美学参考依据。不同人群喜爱的乳房形态存在差异，整形医生在进行手术设计时应根据求美者的既往经历、身体条件、乳房现状、求美目的等因素，结合公认的美学标准，做出适当的调整，进行个性化手术，从而获得最大满意度。

Background: It is necessary to make sure that the aesthetic demands of the patients in order to judge whether the outcome of breast plastic surgery can meet the requirements of the patients and ensure the satisfactory results. It has been reported in the literature that the ideal position of the nipple and the standard of the evaluation of breast symmetry. However, there is no widely accepted standard for breast shape, which is an important aspect of breast aesthetics, not to mention accurate quantitative research. In addition to the aesthetic standards of the public, there is a common aesthetic difference among individuals. To meet the demands of different individuals, it is a pressing need to obtain the aesthetic preference of breast shape. However, how to accurately reflect the aesthetic consciousness of the individual to the shape of the breast has always been a technical problem. In recent years, the application of 3D scanning technology in breast measurement and analysis make it possible to obtain accurate breast three-dimensional data, and the development of data visualization technology for breast aesthetic research provides a technical method. In this study, the three-dimensional scanning technique was used to measure the breasts with different aesthetic scores. The morphological characteristics of breasts with high aesthetic scores and the distribution range of related parameters were analyzed. Data visualization techniques were used to restore the breast morphological data to 3D breast models, then the proportion of the relevant parameters of the ideal breast shape was obtained by the population survey, and the basic reference and objective evidence of breast aesthetics were provided for the surgical design. By analyzing the difference of breast shape preference among variety groups, the goal and direction were provided for the individual operation. Objective: 1. To obtain the three-dimensional data, the proportion, the characteristics of breast with different aesthetic scores, and to find out the key parameters and their range, which provide the basic data for studying the morphological characteristics of the ideal breast. 2. To establish the method of visualizing the breast parameter data into three-dimensional images of breasts with different proportion. Get the proportion of the ideal breast shape considered by the public. Analyze the different breast shape preference of variety people. Provide the objective reference for the surgical design, and lay the foundation for personalized surgery. Methods: 1. We performed a unilateral breast shape self-rating score and plastic surgeon score on women who came to our hospital from March 2016 to June 2016. Breasts with average score ≥ 4 points were adopted into the high sore (HS) group, and breasts with average score <4 points were included in the low score (LS) group. All breasts and anterior thorax data were collected by scanning in three dimensions to measure the absolute value and proportion of the sternal notch to the nipple distance(SN-N), the distance from the nipple to the midline, the vertical distance of the nipple to the inframammary fold(N-IMF), the breast base width(BW), the breast protrusion(BP). Differences in parameters and proportion between HS breasts and LS breasts were analyzed, and get the characteristics of the breast and the proportion of the distribution range of HS breasts. The ROC curve of each parameter was drawn to find the breast parameters which had significantly influence on the satisfaction and could predict the satisfaction well, and the optimal cutoff value of the breast parameters was found according to the relationship between sensitivity and specificity. 2. Referring to the reported research results and results of Part 1 in this study, 3D dynamic simulation models of breast known parameters were made. The breast model parameters to determine the breast shape contained the breast upper pole length(UPL), N-IMF, BP, each of which had 5 successive changes in the value. The breast upper pole fullness(UPF) was linear or slightly convex. The remaining breast parameters fixed. A total of 5 × 5 × 5 × 2 = 250 breast models were made. After collecting the subject's basic information, the subjects including plastic surgeons, patients and lay people scored aesthetically graded 250 breasts in random order. Multiple regression analysis was performed to find the relationship between aesthetic score and breast parameter proportion, and the parameter proportion of ideal breast was obtained. Introduce the interaction between the population characteristics and the breast parameter proportion to explore the different preferences of variety groups of people. Results: 1. A total of 179 unilateral breast data were collected from 98 patients, of which 68 breasts were included in the HS group and 111 breasts were included in the LS group. HS breast group (15.0 ± 1.4 cm) and LS breast group (14.7 ± 1.6 cm) had no significant difference in BW (p = 0.28). SN-N of HS (19.7 ± 1.5cm) and LS breast group (20.5 ± 4.0cm) were not significantly different (p = 0.12). N-M of HS (9.6 ± 0.9 cm) was slightly longer than that of LS breast group (9.2 ± 1.5 cm) (p = 0.03). N-IMF of HS breast group (6.1 ± 0.7cm) significantly longer than that of LS group (4.5 ± 1.2 cm) (p <0.001). BP of HS breast group (3.0 ± 1.8 cm) was significantly higher than that of LS group (2.64 ± 0.22) (p <0.001). The ratio of the parameters to BR (half of the width of the breast width) was calculated. There was no significant difference between the N-M/BR of HS group (1.29 ± 0.11) and LS group (1.25 ± 0.16) (p = 0.05). SN-N/BR of HS group (2.64 ± 0.22) was shorter than that of LS group (2.78 ± 0.41) (p = 0.01). N-IMF/BR of HS (0.82 ± 0.13) was significantly longer than that of LS group (0.63 ± 0.17) (p <0.05). BP/BR of HS group (0.60 ± 0.17) was significantly higher than that of LS group (0.41 ± 0.22) (p <0.001). The area under the ROC curve of the BP/BR index is 0.747, the area under the N-IMF/BR curve is 0.815, the area under the BP/BR + N-IMF/BR curve is 0.865, which had the ability to determine the satisfaction level. The optimal cutoff value of BP/BR was 0.635, and that of N-IMF/BR was 0.723. The optimal cutoff value of BP/BR + N-IMF/BR was 4.1 × BP/BR + 8.2 × N-IMF/BR = 8.123. 2. A total of 183 subjects completed the aesthetic preference test, 45750 times aesthetic rating score were collected. Cronbach's α was 0.99, and the results are stable and reliable. UPL/BR, N-IMF/BR, BP/BR, and UPF all had an impact on the breast aesthetic score. Slightly convex UPF had a higher score than linear UPF. The quadratic coefficients of UPL/BR, N-IMF/BR, BP/BR in the regression equation were statistically significant, and the quadratic term were negative. The regression curve was the parabolic and open downwards. Breast with slightly convex UPF and with the ratio of BR:N-IMF:UPL:BP=1: 1.05: 1.15: 0.94 got the highest breast aesthetic score. People with different age, BMI, gender, marriage history, fertility history, mast surgery history, career, and purpose had different breast shape aesthetic preferences. Conclusions: 1. Breast base width had no effect on breast aesthetic score, and it can be used as a relatively fixed reference to describe the proportion of breast shape. There were significant differences in the breast protrusion and the vertical distance from the nipple to the inframammary fold between breasts of different satisfaction. The breast protrusion and vertical distance from the nipple to the inframammary folds could be used as indexes to judge the breast shape aesthetic. In this part, we obtained the range of high aesthetic score breast parameter proportion, which provides the basis for further exploration of the precise proportion of ideal breast. 2. The ideal breast had a pole of slightly convex, and met the ratio of breast radius: the upper pole length : the lower pole length : breast protrusion = 1 : 1.15 : 1.05 : 0.94, which provided an evidence to the hypothesis that the lower half of the ideal breast was hemispherical, and accurate data support for breast plastic surgery. There were differences in breast shape preference among variety people. Factors like he past experience, physical condition, breast status and purpose of seeking surgery should be considered when the surgeons make surgical plans. Recognizing the general aesthetic standard proved by our findings and making appropriate adjustments individually mentioned in our study both played important role in achieving maximum satisfaction.