Imaging the neocortex with visible light spectroscopy

用可见光谱对新皮质进行成像

• 批准号: 6797357
• 负责人: ROGER J SPRINGETT
• 金额: $ 21.67万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2006-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6797357
• 关键词: bioimaging /biomedical imaging; biomedical equipment development; brain imaging /visualization /scanning; brain mapping; charge coupled device camera; colorimetry; cytochrome c; cytochrome oxidase; hemoglobin; laboratory mouse; neocortex; statistics /biometry; three dimensional imaging /topography; tomography

DESCRIPTION (provided by applicant): We will build a visible light spectroscopy (VLS) system to probe the neocortex of mice and immature rats. This system will use multiple optical fibers placed on the exposed skull and measure complete attenuation spectra from 500 to 630nm between pairs of fibers using white light illumination and a multi-channel imaging spectrograph equipped with a cooled CCD detector. We have developed and validated a novel algorithm to calculate the concentration of reduced cytochrome c and reduced cytochrome oxidase as well as absolute hemoglobin concentration and saturation directly from these attenuation spectra. We will use this algorithm to reconstruct a topographic map of the cortex between pairs of optodes and extend this algorithm to reconstruct a full 3 dimensional tomographic image of the cortex. The topographic system will consist of 25 transmit fibers and 16 receive fibers with a spacing of 1.25mm allowing us to span 7x7mm of the neocortex. We will use nearest neighbor pairs of optodes to map the neo cortex with a spatial resolution of 1.56mm 2. Temporal resolution will be 1 second. The tomographic system will consist of an array of 36 fibers spaced lmm apart spanning an area x5mm across the neocortex. We will sequence through all 36 fibers making each one in turn a transmit fiber and the remaining 35 receive fibers. We will apply a tomographic reconstruction based on a Monte-Carlo simulation of the transport of light through the tissue to reconstruct the gray matter of the cortex in 3 dimensions. We expect sufficient signal to make measurements up to fourth nearest neighbor allowing an in-plane resolution of lmm 2 and a depth resolution of 0.25mm. Temporal resolution will be 1.5 seconds. The ability to directly image signals from the mitochondria will make this system unique and will be invaluable in following the metabolic consequences of spreading depression and seizure propagation as well probing the mechanisms of ischemic and excitotoxic cell death.

描述（由申请人提供）：我们将构建一个可见的光谱（VLS）系统，以探测小鼠和未成熟大鼠的新皮层。该系统将使用裸露的头骨上使用多个光纤，并使用白光照明和配备冷却的CCD检测器配备的多通道成像光谱仪测量成对纤维之间的500至630nm的完整衰减光谱。我们已经开发并验证了一种新型算法，以计算细胞色素C的浓度，并降低细胞色素氧化酶以及绝对的血红蛋白浓度和直接从这些衰减光谱中的饱和度。我们将使用此算法来重建一对optodes之间的皮质的地形图，并扩展该算法以重建皮层的完整3维层析成像图像。地形系统将由25个发射纤维组成，16个接收纤维，间距为1.25mm，使我们能够跨越7x7mm的新皮层。我们将使用最近的Optodes对邻居对以1.56mm 2的空间分辨率绘制新皮层。时间分辨率为1秒。 层析成像系统将由一个横跨NMM的36个纤维组成，跨越了X5mm。我们将通过所有36个纤维进行序列，使每纤维依次将纤维发射纤维，其余35个接收纤维。我们将基于对光线通过组织的传输的蒙特卡洛模拟进行断层造影重建，以在3维中重建皮质的灰质。我们期望足够的信号使最高第四个邻居的测量值允许LMM 2的平面分辨率和0.25mm的深度分辨率。时间分辨率为1.5秒。直接从线粒体形成信号的能力将使该系统与众不同，并且在遵循扩散抑郁和癫痫发作的代谢后果以及探测缺血性和兴奋性细胞死亡机制的代谢后果方面将是无价的。