Liu Yidi, Zhu Dan, Xu Jingjiang, Wang Ying, Feng Wei, Chen Defu, Li Yunqi, Liu Haolin, Guo Xianghuan, Qiu Haixia, Gu Ying
Department of Laser Medicine, First Medical Center of PLA General Hospital, Beijing, 100853, China.
Huazhong University of Science and Technology, Key Laboratory of Biomedical Photonics of Ministry of Education, Department of Biomedical Engineering, Wuhan, 430033, China.
Photodiagnosis Photodyn Ther. 2020 Jun;30:101734. doi: 10.1016/j.pdpdt.2020.101734. Epub 2020 Apr 8.
Optical coherence tomography angiography (OCTA) is an emerging imaging technique which shows its advantages over visualizing microcirculation with free label. However, its shortcomings in imaging depth limit its development in dermatological field. Nowadays, the newly optical clearing agent (OCA) designed for skin optical imaging demonstrates its potential. In our study, whether this OCA can improve the imaging ability of OCTA in healthy human skin and whether the combination of them is beneficial to compare the lesions and the contralateral normal skins in the patients with port wine stains (PWS) have been investigated.
Five healthy volunteers and 3 PWS patients were recruited in this study. In terms of healthy people, the opisthenar area which has same structure information as facial skin was taken for investigating the OCA's ability of enhancing OCTA imaging depth on healthy human skin, besides, in order to verifying whether the exists of skin corneum interfere OCA's function, we compared the effect of only using OCA with that of comprehensive using pre-processing skin and OCA. There are one physical removing corneum method by using medical tape to strip opisthenar skin for over 20-time and one chemical way through applying exfoliating cream. For PWS patient, the combining using OCA and OCTA was applied at the lesion area and the contralateral normal area for the purpose of verifying their ability to provide the information of vessels.
This novel OCA had excellent efficacy to increase the penetration depth of human opisthenar skin for the OCTA imaging by approximately 0.16 ± 0.03 mm. Pre-processing of stratum corneum with an exfoliating cream or medical tape stripping did not further benefit the penetrating efficacy of the OCA. Moreover, according to a comprehensive analysis of the OCTA images enhanced by the OCA, the PWS lesions usually have larger density and diameter of the vessels which located in deep layers (beyond 0.21 mm) than the contralateral normal skin.
The OCTA imaging depth and contrast were significantly improved by the OCA. The OCA application is a simple and efficient clinical procedure for OCTA enhancement. Moreover, it demonstrated great clinical value to compare the normal skin and the PWS lesions in the patients by the enhanced OCTA imaging.
光学相干断层扫描血管造影术（OCTA）是一种新兴的成像技术，在可视化无标记微循环方面显示出优势。然而，其成像深度的不足限制了它在皮肤科领域的发展。如今，为皮肤光学成像设计的新型光学透明剂（OCA）展现出了潜力。在我们的研究中，探究了这种OCA能否提高OCTA对健康人皮肤的成像能力，以及它们的组合是否有利于比较葡萄酒色斑（PWS）患者的病变皮肤和对侧正常皮肤。
本研究招募了5名健康志愿者和3名PWS患者。对于健康人，选取与面部皮肤结构信息相同的手掌鱼际区域来研究OCA增强OCTA对健康人皮肤成像深度的能力，此外，为了验证角质层的存在是否干扰OCA的功能，我们比较了仅使用OCA与预处理皮肤后再使用OCA的效果。有两种预处理方法，一种是使用医用胶带对鱼际皮肤进行20多次剥离的物理去角质方法，另一种是涂抹去角质霜的化学方法。对于PWS患者，将OCA和OCTA联合应用于病变区域和对侧正常区域，以验证它们提供血管信息的能力。
这种新型OCA在增加OCTA对人手掌鱼际皮肤成像的穿透深度方面具有出色的效果，穿透深度增加了约0.16±0.03毫米。用去角质霜或医用胶带剥离角质层预处理并没有进一步提高OCA的穿透效果。此外，通过对OCA增强的OCTA图像进行综合分析，PWS病变处位于深层（超过0.21毫米）的血管通常比其对侧正常皮肤的血管密度更大、直径更粗。
OCA显著提高了OCTA的成像深度和对比度。应用OCA是一种简单有效的增强OCTA的临床方法。此外，通过增强的OCTA成像比较患者的正常皮肤和PWS病变具有很大的临床价值。
