Diffuse Optical Brain Imaging

漫射光学脑成像

• 批准号: 8351241
• 负责人: Amir H Gandjbakhche
• 金额: $ 18.2万
• 依托单位: EUNICE KENNEDY SHRIVER NATIONAL INSTITUTE OF CHILD HEALTH & HUMAN DEVELOPMENT
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8351241
• 关键词: 3-Dimensional; Address; Adult; Age; Area; Atlases; Behavior; Biophotonics; Blood Vessels; Brain; Brain Part; Brain imaging; Brain region; Child; Childhood; Chronic; Clinical; Cognitive; Collaborations; Collection; Conflict (Psychology); Coupling; Data; Data Correlations; Development; Devices; Diffuse; Electroencephalography; Epilepsy; Evaluation; Event; Fiber; Frequencies; Functional Imaging; Functional Magnetic Resonance Imaging; Funding; Grant; Helmet; Hematoma; Hemispherectomy; Hour; Image; Imaging Techniques; Imaging technology; Institutional Review Boards; Judgment; Knowledge; Lasers; Legal patent; Magnetic Resonance Imaging; Maps; Medicine; Methods; Modeling; Monitor; Morphologic artifacts; Motion; Motor Cortex; National Institute of Child Health and Human Development; National Institute of Mental Health; National Institute of Neurological Disorders and Stroke; Nature; Neurosciences; Noise; Operative Surgical Procedures; Optical Image Reconstruction; Optics; Paper; Patients; Physiological; Population; Prefrontal Cortex; Process; Rehabilitation therapy; Relative (related person); Research; Rest; Scientist; Secure; Short-Term Memory; Side; Signal Transduction; Societies; Soldier; Source; Surface; System; TBI Patients; Techniques; Technology; Testing; Time; Tissues; Traumatic Brain Injury; Triage; Universities; Veterans; Visual Cortex; Work; autism spectrum disorder; base; bench to bedside; clinical application; cohort; density; design; detector; healthy volunteer; hemodynamics; indexing; instrument; interest; lens; miniaturize; multitask; neuropsychological; novel; novel strategies; optical imaging; patient population; photonics; prototype; research clinical testing; research study; response; technique development; tool

Diffuse Optical Imaging (DOI) allows us access to the hemodynamic response in tissue. It has been shown that we can, by detecting the effects of neuro-vascular coupling, relate this to functional events in the brain. Existing technologies in DOI are limited by a number of factors, but most strongly by the absence of viable clinical applications where they may be applied. In this project we are targeting veterans (at the upper end of the pediatric population) with penetrating Traumatic Brain Injury (TBI) and Autistic Spectrum Disorder (ASD) patients. These patients are low-functioning and typically pediatric populations. Over the course of the 2011 fiscal year we have secured a Bench to Bedside grant to fund the latter study and extended the funding for the former study under the Center for Neuro-Rehabilitative Medicine. We have again had several presentations accepted at the Society for Neuroscience and have several key papers in submission on our various projects. We have completed the development of our fiber based instrument and are finishing assembling a second instrument through our collaborators at Drexel). We have commenced studies using instruments at our lab and at our other collaborators lab in Georgetown. The latter is a DOI instruments combined with EEG. Clinically we are continuing testing with healthy volunteers and have some initial data from TBI subjects. We have an in-place IRB through NICHD to test our prototype systems here at NICHD for both projects including a neuropsychological evaluation. Alongside our tests for cognitive tasks (event complexity judgment task, a verbal working memory task, and a multi-task) we have further developed an approach for resting state and functional connectivity. For the resting/functional state connectivity existing techniques such as correlation and data-driven decompositions, for assessing functional connectivity, generally assume temporal stationary for the brain signals over the duration of the recording. Such an assumption would result in not detecting the dynamic changes that exist in functional connectivity between engaged regions of the brain. We have been investigating time-frequency analysis techniques to capture the dynamic behavior of connectivity across the prefrontal cortex, at both resting-state and task-based experiments. With the inclusion of neuropsychological evaluation we are well on our way to providing the basis for our ASD study, once complete we will be able to use the existing data from NIMH to identify a patient cohort to closely match our healthy subject population. Theoretically we are currently finishing the development of techniques to handle the shortcomings of current DOI techniques. We have identified an approach using stereotactic imaging that allows us to co-register our optical data to the MNI atlas with accuracy matching that of similar MRI experiments. Currently this requires the existence of a patient specific MRI and our focus is on the ability to remove this requirement as this may not be available for our target patient populations. Initial results have also been done on developing novel techniques to accelerate optical image reconstruction. Currently techniques for 3 dimensional imaging of optical data require days or at best hours to reconstruct by expert users. We are developing novel approaches using a combination of our atlasing approach and analytical functions to address both these issues with DOI. Our collaboration with NINDS has fully developed a fiber based imager which has added to our array devices for comparison and contrast of DOI techniques. This particular system has also increased the areas of the brain accessible to our devices expanding us away from the prefrontal cortex to include motor and visual cortices. Also we have a fully miniaturized system under development in association with our collaborators at Drexel. Initial designs for optical transmitter and receiver have been implemented and the functionality of each module has been verified experimentally. Quad vertical cavity surface emitting laser diodes are used in the transmitter, and the system takes advantage of Gradient-Index (GRIN) lens technology to achieve excellent optical collection efficiency. We are currently working on the integration of the modules. These projects will combine to produce fully wearable DOI for Near Infrared functional imaging. Our theoretical research is also examining motion artifact as a signal instead of noise. Initial results suggest that if we can model the motion of our imaging system relative to the subject via the helmet interface (a process being worked on by our instrumentalists), we should further be able to enhance optical signals to an unprecedented level of accuracy and quantitation in the field. The final part of the brain project involves structural imaging. We have developed a novel approach to detect hematomas in a rapid handheld device. This approach would greatly help for the triaging for the presence of hematomas and greatly increase the efficiency of use of more expensive limited access technologies such as CT or MRI. Theoretical results indicate the device will work to detect Dural hematomas and also that the potential to map them with a simple handheld device exists. Such a device could be critical to aiding in surgical interventions where CT or MRI is unavailable. The approach being developed has undergone initial testing with a prototype imager on phantoms and initial results suggest that the more sources and more detectors at higher density paradigm for better near infra-red imaging may not be correct. In fact it may be possible to achieve faster structural imaging of similar quality with smaller devices. Unfortunately such approaches cannot be applied to functional imaging.

漫反射光学成像 (DOI) 使我们能够了解组织中的血流动力学响应。事实证明，我们可以通过检测神经血管耦合的影响，将其与大脑的功能事件联系起来。 DOI 中的现有技术受到许多因素的限制，但最严重的是缺乏可行的临床应用。在这个项目中，我们的目标是患有穿透性脑外伤 (TBI) 和自闭症谱系障碍 (ASD) 的退伍军人（儿科人群中的高端）。这些患者功能低下，通常是儿科人群。 在 2011 财年中，我们获得了一项从实验室到床边的拨款，为后一项研究提供资金，并为神经康复医学中心的前一项研究提供了资助。我们再次有几篇演讲被神经科学学会接受，并提交了关于我们各个项目的几篇关键论文。我们已经完成了基于纤维的仪器的开发，并正在通过我们在 Drexel 的合作者完成第二台仪器的组装。我们已经开始使用我们实验室和乔治敦其他合作者实验室的仪器进行研究。后者是与EEG结合的DOI仪器。 在临床上，我们正在继续对健康志愿者进行测试，并从 TBI 受试者那里获得一些初步数据。我们通过 NICHD 设立了一个 IRB，来测试我们在 NICHD 的两个项目的原型系统，包括神经心理学评估。除了我们的认知任务测试（事件复杂性判断任务、言语工作记忆任务和多任务）之外，我们还进一步开发了一种用于静息状态和功能连接的方法。对于静息/功能状态连接性，现有技术（例如相关性和数据驱动分解）用于评估功能连接性，通常假设大脑信号在记录期间处于时间静止状态。这种假设将导致无法检测到大脑参与区域之间功能连接中存在的动态变化。我们一直在研究时频分析技术，以在静息状态和基于任务的实验中捕获前额皮质连接的动态行为。通过纳入神经心理学评估，我们正在为 ASD 研究提供基础，一旦完成，我们将能够使用 NIMH 的现有数据来识别与我们的健康受试者群体密切匹配的患者队列。 理论上，我们目前正在完成技术的开发，以解决当前 DOI 技术的缺点。我们已经找到了一种使用立体定向成像的方法，使我们能够将光学数据共同注册到 MNI 图集中，其精度与类似 MRI 实验相匹配。目前，这需要存在患者特定的 MRI，我们的重点是消除这一要求的能力，因为这可能不适用于我们的目标患者群体。在开发加速光学图像重建的新技术方面也取得了初步成果。目前，光学数据的 3 维成像技术需要专家用户数天或最多数小时才能重建。我们正在开发新的方法，结合我们的图集方法和分析功能来解决 DOI 的这两个问题。 我们与 NINDS 的合作已完全开发出基于光纤的成像仪，该成像仪已添加到我们的阵列设备中，用于 DOI 技术的比较和对比。这个特殊的系统还增加了我们的设备可访问的大脑区域，将我们从前额叶皮层扩展到包括运动皮层和视觉皮层。此外，我们正在与 Drexel 的合作者合作开发一个完全小型化的系统。光发射机和光接收机的初步设计已经实现，并且每个模块的功能都已经过实验验证。发射器采用四垂直腔表面发射激光二极管，系统利用梯度折射率（GRIN）透镜技术实现出色的光学收集效率。目前我们正在致力于模块的集成。这些项目将结合起来生产用于近红外功能成像的完全可穿戴 DOI。我们的理论研究还将运动伪影作为信号而不是噪声进行检查。初步结果表明，如果我们能够通过头盔接口对成像系统相对于受试者的运动进行建模（我们的仪器专家正在研究这一过程），我们应该能够进一步将光学信号增强到该领域前所未有的准确性和定量水平。 大脑项目的最后一部分涉及结构成像。我们开发了一种在快速手持设备中检测血肿的新颖方法。这种方法将极大地有助于对血肿的存在进行分类，并大大提高 CT 或 MRI 等更昂贵的有限访问技术的使用效率。理论结果表明，该设备将能够检测硬脑膜血肿，并且存在使用简单的手持设备绘制硬脑膜血肿图的潜力。在无法使用 CT 或 MRI 的情况下，此类设备对于辅助外科手术至关重要。正在开发的方法已经在模型上使用原型成像仪进行了初步测试，初步结果表明，在更高密度范式下使用更多源和更多探测器来获得更好的近红外成像可能并不正确。事实上，使用更小的设备可以更快地实现类似质量的结构成像。不幸的是，这种方法不能应用于功能成像。