Optical Tomography of Intrinsic Signals in Rat Cortex

大鼠皮层固有信号的光学断层扫描

• 批准号: 8464292
• 负责人: Bruce J. Tromberg
• 金额: $ 14.12万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2015-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8464292
• 关键词: Adult; Algorithms; Alzheimer' s Disease; Architecture; Ballistics; Beds; Blood Vessels; Blood flow; Brain; Brain Pathology; Brain imaging; Cattle; Cerebrum; Communities; Complex; Confocal Microscopy; Coupling; Development; Devices; Diffuse; Dimensions; Disease; Fat emulsion; Frequencies; Functional Imaging; Functional Magnetic Resonance Imaging; Funding; Goals; Hemoglobin; Heterogeneity; Image; Image Analysis; Imaging Techniques; Individual; Laboratories; Lateral; Length; Light; Lighting; Measurement; Measures; Metabolic; Methods; Microscopy; Modeling; Monitor; Monte Carlo Method; Neurons; Neurosciences; Optical Methods; Optical Tomography; Optics; Pattern; Play; Property; Protocols documentation; Rattus; Relative (related person); Research; Research Personnel; Resolution; Rodent Model; Role; Signal Transduction; Simulate; Somatosensory Cortex; Source; Spectrum Analysis; Stimulus; Stroke; Surface; Techniques; Testing; Three-Dimensional Imaging; Tissues; Vibrissae; Visible Radiation; Work; base; deoxyhemoglobin; design; digital; gain of function; hemodynamics; image reconstruction; imaging modality; in vivo; insight; instrument; instrumentation; light intensity; light scattering; meetings; millimeter; optical imaging; reconstruction; response; spectroscopic imaging; stem; success; tomography; tool; two-dimensional

DESCRIPTION (provided by applicant): Hemodynamic activity plays an important role in brain function and disease. The connection between neuronal and vascular activity in the brain is poorly understood. This in part stems from the lack of quantitative methods to localize hemodynamic changes in three-dimensions with sufficient temporal and spatial resolution to monitor the progression of the hemodynamic response to a stimulus. Intrinsic Signal Optical Imaging (ISOI) is a camera-based method for imaging cortical activity. ISOI allows researchers to image the hemodynamic changes that accompany neuronal activity by measuring changes in intensity of light remitted from an illuminated brain. Because it is capable of imaging large cortical regions with high spatial and temporal resolution, ISOI has become an important tool for studying the functional architecture and plasticity of the cortex. However, ISOI has two major limitations that have hampered our ability to decipher the complex relationship between hemodynamics and neuronal activity. First, it is often difficult to determine whether measured signals are due to changes in hemoglobin concentration or alterations in hemoglobin oxygenation state. Second, ISOI only provides two-dimensional images, and thus cannot localize hemodynamic activity in depth. We have recently acquired preliminary results using multi-spectral ISOI that demonstrate tomographic localization of hemodynamic activity in rat cortex during whisker stimulation. This is possible because near- infrared light penetrates much more deeply into the brain than visible light. By using many wavelengths of light spanning both the visible and near-infrared (NIR), and applying tomographic imaging methods, we have succeeded in forming three-dimensional tomographic images of hemodynamic activity in the rat somatosensory cortex. In addition, we have also been able to quantify dynamic changes in hemoglobin concentration and oxygenation state by employing spatial frequency domain imaging (SFDI) techniques in conjunction with multi-spectral image analysis. The purpose of this R21 proposal is to validate and refine this exciting new finding. Over the course of the two year funding period, we will incorporate snapshot hyperspectral imaging into our established optical brain imaging methods - ISOI and SFDI. We will optimize our tomographic image reconstruction methods to work in the rat cortex using dynamic tissue simulating phantoms, and validate our approach using our established protocol for whisker stimulation in the adult rat.

描述（由申请人提供）：血液动力学活性在大脑功能和疾病中起重要作用。大脑中神经元和血管活性之间的联系知之甚少。这部分源于缺乏定量方法来在三维中定位血液动力学变化，并具有足够的时间和空间分辨率来监测血液动力学对刺激的血液动力学反应的进展。固有信号光学成像（ISOI）是一种基于摄像机成像皮质活性的方法。 ISOI允许研究人员通过测量从照明大脑中恢复的光强度的变化来对伴随神经元活性的血液动力学变化进行想象。由于它能够成像具有高空间和时间分辨率的大型皮质区域，因此ISOI已成为研究皮质功能结构和可塑性的重要工具。但是，ISOI具有两个主要局限性，这阻碍了我们破译血液动力学与神经元活性之间复杂关系的能力。首先，通常很难确定测量信号是由于血红蛋白浓度的变化或血红蛋白氧合状态的变化所致。其次，ISOI仅提供二维图像，因此无法深入定位血液动力学活性。我们最近使用多光谱ISOI获得了初步结果，该结果证明了在晶须刺激过程中大鼠皮层中血液动力学活性的层析成像定位。这是可能的，因为近红外光渗透到大脑中比可见光更深入。通过使用跨越可见和近红外（NIR）的许多波长，以及应用层析成像方法，我们成功地形成了大鼠体感皮质中血液动力学活性的三维层析成像图像。此外，我们还能够通过采用空间频域成像（SFDI）技术以及多光谱图像分析来量化血红蛋白浓度和氧合状态的动态变化。该R21提案的目的是验证和完善这一令人兴奋的新发现。在两年的资金期间，我们将将快照高光谱成像纳入我们已建立的光学脑成像方法-ISOI和SFDI中。我们将使用模拟幻影的动态组织优化我们的层析成像图像重建方法，以在大鼠皮层中起作用，并使用我们既定的成年大鼠中的晶须刺激方案来验证我们的方法。