University of Campinas, Department of Pathology, Campinas, Brazil.
University of Campinas, Department of Dermatology, Campinas, Brazil.
J Biomed Opt. 2018 Dec;23(12):1-7. doi: 10.1117/1.JBO.23.12.126001.
Sarcoidosis and tuberculoid leprosy (TL) are prototypes of granulomatous inflammation in dermatology, which embody one of the histopathology limitations in distinguishing some diseases. Recent advances in the use of nonlinear optical microscopy in skin have enabled techniques, such as second-harmonic generation (SHG), to become powerful tools to study the physical and biochemical properties of skin. We use SHG images to analyze the collagen network, to distinguish differences between sarcoidosis and TL granulomas. SHG images obtained from skin biopsies of 33 patients with TL and 24 with sarcoidosis retrospectively were analyzed using first-order statistics (FOS) and second-order statistics, such as gray-level co-occurrence matrix (GLCM). Among the four parameters evaluated (optical density, entropy, contrast, and second angular moment), only contrast demonstrated statistical significance, being higher in sarcoidosis (p = 0.02; 4908.31 versus 2822.17). The results may indicate insufficient differentiating power for most tested FOS and GLCM parameters in classifying sarcoidosis and TL granulomas, when used individually. But in combination with histopathology (H&E and complementary stains, such as silver and fast acid stains), SHG analysis, like contrast, can contribute to distinguishing between these diseases. This study can provide a way to evaluate collagen distribution in granulomatous diseases.
结节病和结核样麻风（TL）是皮肤科中肉芽肿性炎症的典型代表，它们体现了组织病理学在区分某些疾病方面的局限性之一。皮肤非线性光学显微镜的应用的最新进展使二次谐波产生（SHG）等技术成为研究皮肤物理和生化特性的有力工具。我们使用 SHG 图像来分析胶原网络，以区分结节病和 TL 肉芽肿之间的差异。我们使用一阶统计（FOS）和二阶统计（如灰度共生矩阵（GLCM））对回顾性分析的 33 例 TL 和 24 例结节病患者的皮肤活检 SHG 图像进行了分析。在评估的四个参数（光密度、熵、对比度和二阶矩）中，只有对比度具有统计学意义，在结节病中更高（p=0.02；4908.31 与 2822.17）。结果表明，当单独使用时，大多数测试的 FOS 和 GLCM 参数在分类结节病和 TL 肉芽肿方面的区分能力不足。但是，与组织病理学（H&E 和补充染色，如银染和快速酸染色）相结合，SHG 分析（如对比度）可以有助于区分这些疾病。本研究可以为评估肉芽肿性疾病中的胶原分布提供一种方法。
