TRD2: Interferometric Near Infrared Spectroscopy (iNIRS)

项目概要-技术研究与开发项目#2 扩散光谱学（DOS）领域长期以来一直致力于非侵入性深层组织监测 用良性的近红外光然而，临床DOS仪器受到有限的定量 准确性、缺乏深度特异性以及血红蛋白氧合测量的固有模糊性。这些 现有技术仅部分且不充分地应对了这些挑战。我们在UC的团队 Davis最近发明了干涉漫射光谱学（iDOS），其克服了其中的许多缺点。 关键的路障在本TRD中，我们将推进和推广两种互补的iDOS技术： 1)干涉漫射波光谱（iDWS）使用低成本的互补金属氧化物- 半导体（CMOS）传感器，以创建一类新的近红外光学器件， 血流（BF）指数连续和无创。利用干涉测量的光学“技巧”， iDWS将每个CMOS像素转换为对相干光波动敏感的检测器， 高炉深部动力学由于CMOS相机像素便宜且数量众多，iDWS提高了 提高性能并降低光学BF测量的成本。在这里，我们将开发和验证一个 变革性的多次曝光iDWS方法，可实现大脑和其他深部组织测量 用大规模生产的2D百万像素传感器。虽然干涉测量方法是 建立，多重曝光方法是新的和高的影响，使进一步的两个顺序， 与iDWS相比，性能成本比有了显著提高。这些进步将使获取信息民主化 脑BF（CBF），导致1）更好的脑机接口2）CBF的即时评估， 以及3）可穿戴CBF监测器，类似于血压和心率监测器。 2)干涉近红外光谱（iNIRS）通过以下方式增强了iDOS的定量能力： 激光调谐关键的是，iNIRS以数十皮秒的分辨率测量光的飞行时间（TOF）， 使得能够直接量化光学性质。此外，通过测量相干光波动， iNIRS可定量血流指数，并具有解析深度动态的额外能力（例如头皮-颅骨- 脑）。在这个建议中，除了使用iNIRS作为常规连续波的定量辅助之外， 方法，我们将进一步提高iNIRS的TOF分辨率一个数量级，而 实现光谱（多波长）能力。我们还将提供检测子扩散 光在零源-收集器分离，使iNIRS和基于纤维的介观集成 例如iFLIM（TRD 1）和光学相干断层扫描（OCT）。 协作和服务项目被选中代表从显微外科到非侵入性的设置 监测，以及从临床神经监测到手术技能评估到人群筛查的应用。 这些不同的合作将有助于评估和展示iDOS方法的独特能力。

PROJECT SUMMARY – Technology Research and Development Project #2 The field of diffuse optical spectroscopy (DOS) has long held the promise of non-invasive, deep tissue monitoring with benign, near-infrared light. Yet clinical DOS instrumentation has been challenged by limited quantitative accuracy, lack of depth specificity, and the inherent ambiguity of hemoglobin oxygenation measures. These challenges have been only partially, and inadequately, addressed by existing technologies. Our team at UC Davis recently invented interferometric diffuse optical spectroscopy (iDOS), which overcomes many of these critical roadblocks. In this TRD, we will advance and disseminate two complementary iDOS technologies: 1) Interferometric Diffusing Wave Spectroscopy (iDWS) uses low-cost complementary metal–oxide– semiconductor (CMOS) sensors to create a new class of near-infrared optical devices that measure deep blood flow (BF) index continuously and non-invasively. Employing the optical “trick” of interferometry, iDWS transforms each CMOS pixel into a sensitive detector for coherent light fluctuations that encode deep BF dynamics. Since CMOS camera pixels are cheap and numerous, iDWS improves the performance and reduces the cost of optical BF measurements. Here, we will develop and validate a transformative, multi-exposure iDWS approach, to enable brain and other deep tissue measurements in adult humans with mass-produced, 2D megapixel sensors. While the interferometric approach is established, the multi-exposure approach is new and high impact, enabling a further two order-of- magnitude improvement in performance-to-cost over iDWS. These advances will democratize access to cerebral BF (CBF), leading to 1) better brain-computer interfaces 2) point-of-care assessments of CBF, and 3) wearable CBF monitors, analogous to blood pressure and heart rate monitors. 2) Interferometric Near-Infrared Spectroscopy (iNIRS) enhances quantitative capabilities of iDOS through laser tuning. Critically, iNIRS measures the time-of-flight (TOF) of light with tens of picosecond resolution, enabling direct quantification of optical properties. Additionally, by measuring coherent light fluctuations, iNIRS quantifies blood flow index, with the additional ability to resolve dynamics in depth (e.g. scalp-skull- brain). In this proposal, besides using iNIRS as a quantitative adjunct to conventional continuous wave methods, we will further improve the TOF resolution of iNIRS by an order of magnitude, while achieving spectroscopic (multi-wavelength) capabilities. We will also provide detection of sub-diffuse light at null source-collector separation, enabling integration of iNIRS and fiber-based mesoscopic approaches such as iFLIM (TRD 1) and Optical Coherence Tomography (OCT). Collaborative and service projects are selected to represent settings ranging from microsurgery to non-invasive monitoring, and applications from clinical neuro-monitoring to surgical skill assessment to population screening. These diverse collaborations will help to evaluate and demonstrate the unique capabilities of the iDOS approach.