一种低成本、高性价比的穿戴式扩散光学断层人脑成像系统

A Low-cost High Performance-to-price RatioWearable Diffuse Optical Tomography System for Human Brain Imaging

现有扩散光学断层成像(diffuse optical tomography,DOT)系统常采用高档光探测器和放大器,令系统成本居高不下、性价比较低.本文旨在使用全新技术降低系统成本、增加成像深度,研发一套可实用于人脑成像的新型扩散光学断层成像系统.为此采用了成本较低的新型光探测器和一款自主设计研制的光电二极管前置放大器.相较于实验室原有DOT系统,新系统整体成本节约了40%以上.其次,设计了一款具有弹性并可适应多种不规则待测物(subject)外形的无光纤穿戴式脑-机接口(brain computer interface,BCI)装置.本文首次将手持式3D激光扫描仪应用于待测物外形结构和光源-探测器位置信息的精确获取.最后综合应用上述技术装备于人脑形状仿体成像实验中,新系统的目标成像深度提升至35 mm.验证结果说明本系统已具备了实际人脑功能成像能力.

Current diffuse optical tomography(DOT) systems often adopt premium photo detectors and amplifiers, thus leading to a high cost and low performance-to-price ratio to the system. The aim of this work is to investigate the use of novel techniques to reduce the cost of system, increase the imaging depth and develop a new DOT system for practical human brain imaging. In this paper, low-cost photo detectors and a self-developed photodiode pre-amplifier were employed. Comparing to the previous system of our laboratory, the whole cost of the new system was cut by more than 40%. Next, we designed a wearable fiber-free brain computer interface(BCI) which is flexible and can fit well with subjects featuring different shapes. A handheld 3 D laser scanner was initially used to accurately acquire the shape of subjects and the locations of sources and detectors in this work.Finally, the imaging depth of targets was up to 35 mm of the new system in human head-shaped phantom experiments performed with the integrated application of techniques and instruments as mentioned above. This validated result demonstrates that our new system has gained the ability for function real human brain imaging.