IMPROVEMENT OF DEPTH SENSITIVITY TO CEREBRAL HEMODYNAMICS W/ TIME GATED SYSTEM

利用时间门控系统提高脑血流动力学的深度敏感性

• 批准号: 7957659
• 负责人: David A Boas
• 金额: $ 16.36万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2010-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7957659
• 关键词: Brain imaging; Cerebrum; Computer Retrieval of Information on Scientific Projects Database; Detection; Devices; Discrimination; Fiber; Frequencies; Functional Imaging; Funding; Grant; Head; Image; Imaging technology; Institution; Lasers; Length; Photons; Physiologic pulse; Research; Research Personnel; Resources; Sapphire; Source; System; Time; United States National Institutes of Health; base; charge coupled device camera; detector; hemodynamics; interest; response

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. By recording the distribution of times of flight of photons, Time Domain (TD) systems intrinsically provide more information that continuous wave (CW) ones. In particular, they enable depth discrimination at a single source-detector (SD) separation. This is of particular interest for functional brain imaging, where cortical activation is often hidden by superficial systemic response. Our TD device is based on a Ti:Sapphire pulsed laser and an intensified CCD camera (ICCD). We have developed a probe combining depth sensitivity and 2D imaging. It consists in 2 halves  one per hemisphere  each with 4¿4 sources and 3¿3 detectors in a square geometry (SD = 2.5 cm). Each detector consists of 7 fibers of different lengths, for parallel detection at 7 delays. All 126 fibers are imaged in parallel on the ICCD array. The 32 sources are illuminated sequentially, with 4 sets of 8 sources that are turned on during the same CCD frame without causing significant cross-talk. This source time-multiplexing and the parallel detection allow for an imaging frequency of almost 2 Hz for the whole head.

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 通过记录光子飞行时间的分布，时间域(TD)系统本质上提供了更多信息 连续波(CW)波。具体地说，它们能够在单个震源探测器(SD)上实现深度分辨 分离。这对功能性脑成像特别有意义，在功能性脑成像中，皮质激活通常被表面遮盖住 系统性反应。我们的TD装置是基于钛宝石脉冲激光器和增强型CCD相机(ICCD)。我们有 开发了一种结合了深度敏感和2D成像的探头。它由两半组成，每半半球一个，每半个半球 4个光源和3个探测器呈正方形(SD=2.5厘米)。每个探测器由7根不同的光纤组成 长度，用于在7个延迟时进行并行检测。所有126根光纤在ICCD阵列上并行成像。这32个来源是 顺序照明，4组8个信号源在同一个CCD帧期间打开，而不会导致 显著的串音。这种源时分复用和并行检测允许成像频率几乎为2 整个头部的频率为8赫兹。