Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China.
Department of Dermatology, China-Japan Friendship Hospital, Beijing, China.
Skin Res Technol. 2023 May;29(5):e13340. doi: 10.1111/srt.13340.
Noninvasive skin examination evolved rapidly in recent years, with multiphoton microscopy (MPM) and reflectance confocal microscopy (RCM) being used to image in-vivo skin at high resolution. The aim of this study is to compare the imaging clarity between the two techniques and measure the thickness of the epidermis in different body sites. We also measured the degree of skin aging with noninvasive tools.
Fifty-six volunteers were evaluated and measured at three different body sites, including the cheek, volar forearm, and back. We used RCM and MPM to evaluate the clarity of each skin layer, including stratum corneum, stratum granulosum, stratum spinosum, dermo-epidermal junction, and dermis. We measured epidermal thickness (ET) at the three body sites in individuals of different ages and genders. We assessed skin aging by the second harmonic to autofluorescence aging index of dermis (SAAID), and multiple linear regression was used to analyze the factors affecting SAAID.
MPM had advantages in observation of stratum granulosum, collagen fiber, and elastic fiber (p < 0.001), but RCM provided better observation in dermo-epidermal junction layer (p < 0.001). The epidermis was thicker in the cheek area than the volar forearm and back in both RCM and MPM detection, and the average ET measured by MPM was lower than RCM. ET varied among the three body sites with significant differences (p < 0.05). ET was significantly lower at almost all sites in individuals above 40y (p < 0.05). SAAID decreased with age, and more rapidly in women. Cheeks have lower SAAID scores than other body sites.
MPM and RCM provide noninvasive methods for imaging skin and each method has its own advantages. Epidermal thickness and SAAID correlated with age, gender, and different body sites. MPM could also assess the degree of skin aging, which could guide the clinical treatment of patients with diffferent ages and genders in the above body sites.
近年来，无创皮肤检查技术发展迅速，多光子显微镜（MPM）和反射共聚焦显微镜（RCM）已被用于高分辨率的体内皮肤成像。本研究旨在比较两种技术的成像清晰度，并测量不同身体部位的表皮厚度。我们还使用无创工具测量皮肤老化程度。
评估了 56 名志愿者，在三个不同的身体部位（脸颊、前臂掌侧和背部）进行测量。我们使用 RCM 和 MPM 评估每个皮肤层的清晰度，包括角质层、颗粒层、棘层、表皮真皮交界处和真皮。我们测量了不同年龄和性别的个体在三个身体部位的表皮厚度（ET）。我们使用真皮二次谐波至自发荧光老化指数（SAAID）评估皮肤老化程度，并用多元线性回归分析影响 SAAID 的因素。
MPM 在观察颗粒层、胶原纤维和弹性纤维方面具有优势（p<0.001），但 RCM 在表皮真皮交界处的观察更好（p<0.001）。在 RCM 和 MPM 检测中，脸颊区域的表皮比前臂掌侧和背部厚，MPM 测量的平均 ET 低于 RCM。三个身体部位的 ET 存在显著差异（p<0.05）。40 岁以上个体的几乎所有部位的 ET 均显著降低（p<0.05）。SAAID 随年龄降低，女性降低更快。脸颊处的 SAAID 评分低于其他身体部位。
MPM 和 RCM 为皮肤成像提供了非侵入性方法，每种方法都有其优势。表皮厚度和 SAAID 与年龄、性别和不同身体部位有关。MPM 还可以评估皮肤老化程度，这可以指导不同年龄和性别的上述身体部位患者的临床治疗。
