Kikuchi Kumiko, Katsuyama Masako, Yoshikawa Tatsuya, Wakeshima Nozomu, Iizuka Hajime
Shiseido Co., Ltd., MIRAI Technology Institute, Yokohama, Japan.
Research Institute of Psoriasis, Kojinkai Association of Medical Corporation, Sapporo, Japan.
J Dermatol. 2022 Dec;49(12):1245-1254. doi: 10.1111/1346-8138.16561. Epub 2022 Sep 2.
Facial pigmented spots are one of the phenotypes of skin aging, but no quantitative analysis of spot features such as color intensity, size, anatomical position, and number on the cheek has yet been performed. In the current study, we conducted an epidemiological survey of 454 Japanese women in their 20s to 70s and analyzed age-related changes and site differences of facial pigmented spots. Using image analysis of high-resolution digital facial photographs, 4912 individual pigmented spots were quantified according to color, size, anatomical position, and total number on the cheek. As a result of color analysis, the color intensity of individual pigmented spots increased with aging, significantly so between ages 30s and 50s. The age-related increase in melanin index of facial spots was confirmed in all sites but did not significantly differ between facial subregions. Regarding the size of pigmented spots, the frequency of large spots increased with age, and large spots were detected in all facial sites. The total number of pigmented spots on the entire cheek increased with aging, significantly so between the 20s and 40s. The number of pigmented spots tended to increase from the region near the canthi to the lower cheeks. The number of spots was markedly increased in the buccal regions compared with the infraorbital and zygomatic regions. The data and methodology presented in the current study can link the state of facial pigmentation with the various factors involved in the histological development of pigmented spots, opening new possibilities in the fields of skin pharmacology and dermatology.
面部色素沉着斑是皮肤老化的表型之一，但尚未对脸颊上色素沉着斑的颜色强度、大小、解剖位置和数量等特征进行定量分析。在本研究中，我们对454名20多岁至70多岁的日本女性进行了流行病学调查，并分析了面部色素沉着斑的年龄相关变化和部位差异。通过对高分辨率数字面部照片进行图像分析，根据脸颊上的颜色、大小、解剖位置和总数对4912个个体色素沉着斑进行了量化。颜色分析结果显示，个体色素沉着斑的颜色强度随年龄增长而增加，在30多岁至50多岁之间增加显著。面部斑点的黑色素指数随年龄增长而增加在所有部位均得到证实，但面部亚区域之间无显著差异。关于色素沉着斑的大小，大斑点的频率随年龄增加，且在所有面部部位均检测到有大斑点。整个脸颊上色素沉着斑的总数随年龄增长而增加，在20多岁至40多岁之间增加显著。色素沉着斑的数量倾向于从内眦附近区域向下脸颊增加。与眶下和颧区域相比，颊区域的斑点数量明显增加。本研究中呈现的数据和方法可以将面部色素沉着状态与色素沉着斑组织学发展中涉及的各种因素联系起来，为皮肤药理学和皮肤病学领域开辟了新的可能性。
