Broadband near-infrared spectroscopy of heterogeneous tissue

生物医学近红外光谱成像（NIRSI）使用波长在大约700和1000 nm之间的光辐射来测量吸收光的物质（发色团）的浓度（绝对或变化）。虽然近红外光谱仪有望成为一种广泛使用的医疗诊断工具，但迄今为止所研制的仪器的灵敏度仍低于临床所需的水平。我的关键假设是，可以通过开发连续波宽带方法和新型专业信号处理技术来实现NIRSI的必要改进。基于NIRSI的现状和我自己的经验和最近的研究结果，在这个建议中，我请求支持HQP培训和研究宽带和便携式NIRSI技术的发展，用于表征异质组织和捕获人类大脑活动信号。该提案的具体目标包括：1）创建一个宽带NIRSI系统，包括多通道设备和基于光谱导数的新型光谱成像算法; 2）开发定量近红外遥测和脑机接口; 3）开发NIRSI和多模态数据的新型数据分析技术。目前，世界上很少有团体积极参与NIRSI的这些子领域的开发。我的方法将包括强调对限制该技术的信噪比的基本物理因素的理解，开发适当的信号处理方法，并使用光产生和检测技术的最新进展。该计划的实施将为开发适用于临床、军事和其他生物医学应用的新型传感和成像设备铺平道路。两名博士，三名硕士和五名本科生将在拟议的计划内进行培训。

Biomedical Near Infrared Spectral Imaging (NIRSI) uses optical radiation of the waveband between approximately 700 and 1000 nm to measure concentrations (absolute or changes) of substances (chromophores) absorbing light. Although NIRSI have been expected to become a widely used medical diagnostic tool, the sensitivity of the instruments created so far remained below clinically required level. My key hypothesis is that the necessary improvement of NIRSI can be achieved by developing the continuous-wave broadband approach and novel specialized signal processing techniques. Based on the present state of NIRSI and on my own experience and recent research results, in this proposal I request support for the HQP training and research on the development of the broadband and portable NIRSI techniques for the characterization of heterogeneous tissues and capturing of human cerebral activity signals. The specific aims of the proposal include: 1) Creation of a broadband NIRSI system including a multichannel apparatus and novel spectral imaging algorithm based on spectral derivatives; 2) Development of quantitative near-infrared telemetry and brain-computer interface; 3) Development of novel data analysis techniques for NIRSI and multimodal data. Very few groups worldwide are presently active in the development of these subfields of NIRSI. My approach will include the emphasis on the understanding of the fundamental physical factors limiting signal-to-noise ratio of the technique, development of the appropriate signal processing methods, and using recent advances in light generation and detection technologies. The implementation of the proposed program should pave a way towards the development of new classes of sensory and imaging devices suitable for clinical, military and other biomedical applications. Two doctoral, three master, and five undergraduate students will be trained within the proposed program.