Optical coherence tomography (OCT) has gained widespread application for many biomedical applications, yet the traditional array of contrast agents used in incoherent imaging modalities do not provide contrast in OCT. Owing to the high biocompatibility of iron oxides and noble metals, magnetic and plasmonic nanoparticles, respectively, have been developed as OCT contrast agents to enable a range of biological and pre-clinical studies. Here, we provide a review of these developments within the past decade, including an overview of the physical contrast mechanisms and classes of OCT system hardware add-ons needed for magnetic and plasmonic nanoparticle contrast. A comparison of the wide variety of nanoparticle systems is also presented, where the figures of merit depend strongly upon the choice of biological application.

中文翻译：

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光学相干断层扫描中的磁性和等离子对比剂

光学相干断层扫描 (OCT) 已在许多生物医学应用中获得广泛应用，但在非相干成像模式中使用的传统造影剂阵列无法在 OCT 中提供对比度。由于氧化铁和贵金属的高生物相容性，磁性和等离子体纳米粒子分别被开发为 OCT 造影剂，以实现一系列生物学和临床前研究。在这里，我们回顾了过去十年中的这些发展，包括物理对比机制和磁性和等离子体纳米粒子对比所需的 OCT 系统硬件附件类别的概述。还介绍了各种纳米粒子系统的比较，其中优值在很大程度上取决于生物应用的选择。