结合医学影像先验信息的近红外漫射光血流血氧测量技术研究

Measurements of cerebral blood flow and oxygenation are of importance for diagnosis and treatment of various brain diseases. The current methods of near-infrared diffuse optical spectroscopy (DOS) and diffuse correlation spectroscopy (DCS) for blood oxygenation and blood flow measurement are unable to utilize the geometrical and internal component information of tissue. This project will utilize the prior information from medical images as well as DCS/DOS technology to obtain accurate and robust measurements of cerebral blood flow and oxygenation. With aim to reduce the influence of signals from superficial tissues (e.g., scalp and skull) on those from deep tissue (e.g., brain), we plan to integrate the MRI images, as well as the technologies of image reconstruction and photon Monte Carlo simulation, to obtain the head volume characteristics. Furthermore, an Nth-order linear algorithm (NL) recently created by us, will be utilized to accurately extract the blood flow/oxygenation information through combination with head volume characteristics. Additionally, we plan to improve the NL algorithm via computer simulation and phantom experiments, so as to maintain the stability and accuracy of blood flow/oxygenation values under the influence of experimental noise. The outcomes derived from this study will assist in applications of DCS/DOS technologies in brain studies and clinical diagnosis.

人脑部血流和血氧的测量对于多种疾病的诊断和治疗非常重要。目前的近红外漫射光谱及相关光谱（DOS及DCS）测量血氧和血流的技术无法利用被测组织形态和内部成分信息。本项目拟利用医学影像的先验信息和DCS/DOS技术来精确和稳定地测量脑部组织的血流和血氧。为了减少表层组织（头皮和颅骨）的信号对脑皮层血流/血氧测量的影响，本项目拟结合头部的磁共振影像、图像三维重建技术与光子蒙特卡罗仿真技术，从而获得头部组织的空间特征；并利用此信息，使用最新创建的N阶线性算法(NL算法)来求解血流/血氧的信息。为了增加测量的精确性和稳定性，我们将用计算机仿真和仿体实验的方法来定量评测和优化NL算法，从而实现在数据噪声的影响下准确地提取血流和血氧信息。此项目的创新成果将推动DCS/DOS技术在脑科学研究和临床诊断的应用。

本项目为一年期研究项目，主要研究如何利用医学影像的先验信息来改善近红外漫射光谱和相关光谱的血流血氧测量。通过一年的努力，我们完成了研究计划中的内容：建立了可视化平台，并融合医学影像获得了组织的空间特征，在此基础上，我们针对N阶线性算法开发了提取血流和血氧信息的正则化方法和信号去噪算法，并构建了仿体实验系统验证了算法的有效性。本项目取得了多项研究成果，在一年的研究周期中，发表了3篇SCI检索论文，1篇EI检索论文和1篇科技核心论文，在国际和国内会议中做了5次大会特邀或分会场报告，技术成果也获得企业的资金支持，有重要医学转化的潜力。