Intraoperative Optical Imaging of Brain Function

描述(由申请人提供)： 在脑外科手术中，能够评估皮质功能以尽可能减少大脑功能区的切除是至关重要的：尽管术前功能磁共振成像(FMRI)经常用于确定皮质功能区，但它不能在手术期间为外科医生提供实时反馈，而且解释粗大的fMRI信号可能很困难。目前术中功能标测的标准是直接观察“能力中断”的皮层刺激标测。然而，虽然这项技术为外科医生提供了实时反馈，但它只提供了粗略的(大约1厘米)皮质功能的定性空间评估。该方案的目标是开发一种基于双CCD的光学成像系统，能够通过成像脑血流、血容量、血红蛋白氧合和氧代谢的变化来实时定量成像神经外科手术期间的脑功能。为了实现这一点，激光散斑对比成像将与多波长反射成像相结合。在目标1中，我们将开发一种适合在手术室内使用的激光散斑对比成像仪，并使用该仪器对神经外科患者在体感和运动刺激期间的脑血流变化进行成像。我们还将开发和实施用于处理和过滤散斑对比图像的改进算法，以实现脑血流的实时可视化。在目标2中，我们将扩展成像仪器的能力，以包括反射变化的多波长成像，以定量成像血红蛋白体积和氧合变化。这些图像加在一起，将能够计算刺激引起的氧代谢变化。这一独特的仪器有可能通过多种血流动力学和代谢参数，在术中高分辨率、实时地绘制皮质功能图，并有可能在神经外科手术中提供有价值的指导。

DESCRIPTION (provided by applicant): During brain surgery it is critical to be able to assess cortical function in order to minimize resection of eloquent areas of the brain whenever possible: Although pre-operative functional magnetic resonance imaging (fMRI) is often used to define functional areas of the cortex, it does not provide the surgeon with real-time feedback during surgery, and interpretation of the BOLD fMRI signal can be difficult. The current standard for intraoperative functional mapping is electrocortical stimulation mapping with direct observation of 'ability disruption'. However, while this technique provides real-time feedback to the surgeon, it provides only coarse (approximately 1 cm), qualitative spatial assessment of cortical function. The goal of this proposal is to develop a dual CCD based optical imaging system capable of real-time quantitative imaging of brain function during neurosurgery by imaging changes in cerebral blood flow, blood volume, hemoglobin oxygenation and oxygen metabolism. To accomplish this, laser speckle contrast imaging will be combined with multi-wavelength reflectance imaging. We will develop, in Aim 1, a laser speckle contrast imaging instrument suitable for use within the operating room, and use the instrument to image the cerebral blood flow changes during somatosensory and motor stimulation in patients undergoing neurosurgery. We will also develop and implement improved algorithms for processing and filtering of speckle contrast images to enable real-time visualization of cerebral blood flow. In Aim 2 we will extent the capabilities of the imaging instrumentation to include multi-wavelength imaging of reflectance changes for quantitative imaging of hemoglobin volume and oxygenation changes. Together, these images will enable calculation of the stimulation-induced changes in oxygen metabolism. This unique instrument has the potential for high resolution, real-time intraoperative mapping of cortical function through multiple hemodynamic and metabolic parameters, with the potential to provide valuable guidance during neurosurgery.