背景:准确的皮肤颜色测量对于许多医学应用是重要的,包括皮肤疾病的诊断和治疗以及提供颌面部软组织假体。
方法:在本研究中,我们从四个不同的种族群体获得了准确的肤色测量结果(高加索人,中文,库尔德语,泰国人)和四个不同的身体位置(前额,脸颊,内臂,手),以期建立用于医疗和化妆品应用的新肤色数据库。使用分光光度计测量皮肤颜色,并将其转换为与设备无关的标准颜色外观空间(CIELAB),其中皮肤颜色表示为沿三个维度的值:亮度L*,红色a*和黄色b*。然后将皮肤颜色差异和变化评估为种族和身体位置的函数。
结果:我们报告了三个主要结果:(1)在标准颜色外观空间(CIELAB)中绘制时,四个民族的肤色分布明显重叠,虽然存在系统性的均值差异。在种族之间,最显著的皮肤颜色差异出现在黄色维度上,泰国皮肤表现出最高的黄色(b*)值和白种人皮肤最低值。面部发红(a*)在四个种族中是不变的。(2)在不同的身体位置之间,发红(a*)有显著变化,前额显示最高的红度值,内臂显示最低。(3)色域在中国样本中最小,在高加索样本中最大,中国的色域完全是高加索色域。同样,肤色变化最大的是高加索人,也是中国群体中最小的。
结论:广义地说,皮肤颜色变化可以用两个主要因素来解释:亮度和黄色的个体差异主要是由于种族,而发红的差异主要是由于身体位置的不同。亮度的变化更为特殊,可能反映了环境因素的巨大影响,例如暴露在阳光下。
BACKGROUND: Accurate skin colour measurements are important for numerous medical applications including the diagnosis and treatment of cutaneous disorders and the provision of maxillofacial soft tissue prostheses.
METHODS: In this study, we obtained accurate skin colour measurements from four different ethnic groups (Caucasian, Chinese, Kurdish, Thai) and at four different body locations (Forehead, cheek, inner arm, back of hand) with a view of establishing a new skin colour database for medical and cosmetic applications. Skin colours are measured using a spectrophotometer and converted to a device-independent standard colour appearance space (CIELAB) where skin colour is expressed as values along the three dimensions: Lightness L*, Redness a* and Yellowness b*. Skin colour differences and variation are then evaluated as a function of ethnicity and body location.
RESULTS: We report three main results: (1) When plotted in a standard colour appearance space (CIELAB), skin colour distributions for the four ethnic groups overlap significantly, although there are systematic mean differences. Between ethnicities, the most significant skin colour differences occur along the yellowness dimension, with Thai skin exhibiting the highest yellowness (b*) value and Caucasian skin the lowest value. Facial redness (a*) is invariant across the four ethnic groups. (2) Between different body locations, there are significant variations in redness (a*), with the forehead showing the highest redness value and the inner arm the lowest. (3) The colour gamut is smallest in the Chinese sample and largest in the Caucasian sample, with the Chinese gamut lying entirely the Caucasian gamut. Similarly, the largest variability in skin tones is found in the Caucasian group, and the smallest in the Chinese group.
CONCLUSIONS: Broadly speaking, skin colour variation can be explained by two main factors: individual differences in lightness and yellowness are mostly due to ethnicity, whereas differences in redness are primarily due to different body locations. Variations in lightness are more idiosyncratic probably reflecting the large influence of environmental factors such as exposure to sun.