Barton J K, Gossage K W, Xu W, Ranger-Moore J R, Saboda K, Brooks C A, Duckett L D, Salasche S J, Warneke J A, Alberts D S
Division of Biomedical Engineering, The University of Arizona, 1230 E. Speedway Blvd., Tucson, AZ 85721-0104, USA.
Technol Cancer Res Treat. 2003 Dec;2(6):525-35. doi: 10.1177/153303460300200605.
Actinic Keratosis (AK) arises from sun-damaged skin and is the first clinical manifestation in the multistep process of skin carcinogenesis to invasive squamous cell carcinoma. Thus, it is an ideal target for chemopreventive efforts. Noninvasive measures of AK severity are needed to assess the efficacy of chemoprevention agents. We performed a pilot study on 20 participants to investigate the OCT appearance of sun-protected skin of the upper inner arm as well as sun-damaged skin and early AKs of the dorsal forearms, and to determine if features or quantitative measures in Optical Coherence Tomography (OCT) images could be used to reliably differentiate between these categories. OCT images of upper inner arm (normal appearing skin) showed skin layers and features (stratum corneum, epidermis, dermis, blood vessels) seen in previous studies; additionally in this participant group the subcutaneous fat layer was usually identified. Sun-damaged skin was characterized by increased signal in the epidermis and rapid attenuation of light. AKs were diverse in appearance but frequently characterized by high surface reflection, the presence of a low-signal band in the stratum corneum, and heterogeneous appearance in the epidermis/dermis. Significant differences were found between skin categories using measures of stratum corneum and epidermal/dermal depths and intensities. The presence of a dark band in the stratum corneum was 79% sensitive and 100% specific for AK. This study indicates that OCT holds promise as a useful technique for identifying and characterizing AKs and monitoring their response to chemoprevention agents.
光化性角化病（AK）起源于受阳光损伤的皮肤，是皮肤癌发生多步骤过程中向浸润性鳞状细胞癌发展的首个临床表现。因此，它是化学预防的理想靶点。需要采用非侵入性方法来评估AK的严重程度，以评价化学预防药物的疗效。我们对20名参与者进行了一项初步研究，旨在探究上臂内侧受阳光保护皮肤、以及前臂背部受阳光损伤皮肤和早期AK的光学相干断层扫描（OCT）表现，并确定OCT图像中的特征或定量指标是否可用于可靠区分这些类别。上臂内侧（外观正常的皮肤）的OCT图像显示出先前研究中所见到的皮肤层和特征（角质层、表皮、真皮、血管）；此外，在该参与者群体中通常还能识别出皮下脂肪层。受阳光损伤的皮肤表现为表皮信号增强和光线快速衰减。AK的外观各异，但通常具有高表面反射、角质层存在低信号带以及表皮/真皮外观不均一的特点。利用角质层厚度、表皮/真皮深度和强度等指标，发现不同皮肤类别之间存在显著差异。角质层中暗带的存在对AK的敏感性为79%，特异性为100%。本研究表明，OCT有望成为一种用于识别和表征AK以及监测其对化学预防药物反应的有用技术。
