Gene Delivery Research Group, Welsh School of Pharmacy, Cardiff University, Cardiff, CF10 3NB, UK.
Pharm Res. 2011 Jan;28(1):66-81. doi: 10.1007/s11095-010-0167-x. Epub 2010 May 13.
To gather sub-surface in situ images of microneedle-treated human skin, in vivo, using optical coherence tomography (OCT). This is the first study to utilise OCT to investigate the architectural changes that are induced in skin following microneedle application.
Steel, silicon and polymer microneedle devices, with different microneedle arrangements and morphologies, were applied to two anatomical sites in human volunteers following appropriate ethical approval. A state-of-the-art ultrahigh resolution OCT imaging system operating at 800 nm wavelength and <3 µm effective axial resolution was used to visualise the microneedle-treated area during insertion and/or following removal of the device, without any tissue processing.
Transverse images of a microneedle device, in situ, were captured by the OCT system and suggest that the stratified skin tissue is compressed during microneedle application. Following removal of the device, the created microchannels collapse within the in vivo environment and, therefore, for all studied devices, microconduit dimensions are markedly smaller than the microneedle dimensions.
Microchannels created in the upper skin layers by microneedles are less invasive than previous histology predicts. OCT has the potential to play a highly influential role in the future development of microneedle devices and other transdermal delivery systems.
利用光学相干断层扫描（OCT）活体获取微针处理后的人体皮肤的亚表面原位图像。这是第一项利用 OCT 研究微针应用后皮肤结构变化的研究。
经过适当的伦理批准，将具有不同微针排列和形态的钢、硅和聚合物微针装置应用于人体志愿者的两个解剖部位。使用工作在 800nm 波长和<3µm 有效轴向分辨率的最先进的超高分辨率 OCT 成像系统，在不进行任何组织处理的情况下，在插入和/或装置移除期间可视化微针处理区域。
OCT 系统捕获了微针装置的横向图像，表明在微针应用过程中分层皮肤组织被压缩。装置移除后，所创建的微通道在体内环境中塌陷，因此，对于所有研究的装置，微通道尺寸明显小于微针尺寸。
微针在上层皮肤中创建的微通道比以前的组织学预测更具侵入性。OCT 有可能在微针装置和其他经皮给药系统的未来发展中发挥重要作用。
