BRAIN IMPEDANCE MEASUREMENT FOR NEUROLOGICAL EVALUATION

用于神经学评估的脑阻抗测量

• 批准号: 2867678
• 负责人: K Jeffrey Eriksen
• 金额: $ 9.14万
• 依托单位: ELECTRICAL GEODESICS, INC.
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-15 至 2000-04-10
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2867678
• 关键词: bioimaging /biomedical imaging; brain electrical activity; brain imaging /visualization /scanning; computer simulation; electrical conductance; electrical impedance; electroencephalography; electrophysiology; magnetoencephalography; technology /technique development

Accurate electrophysiological neuroimaging using high density EEG and MEG increasingly requires knowledge of both head geometry and electrical conductivity. Head and brain geometry can be obtained from structural tomographic techniques such as CT and MRI, but the conductivity of different head tissues cannot currently be measured. We propose to demonstrate the feasibility of a technique for measuring human scalp, skull, and brain conductivities noninvasively using low-level scalp current injection. The process will first be modeled with computer simulations including the effect of noise and measurement errors. Prototype hardware will be constructed to provide the necessary switching and current injection circuitry, then tested with physical models having known geometry and conductivities. Finally, the entire system will be applied to human subjects to demonstrate its overall practicality. With accurate conductivities, realistic head-brain models can be constructed for individual subjects or patients, making EEG/MEG inverse procedures for spatiotemporal localization of neurological activity more accurate as well. In addition, since the conductivity estimation procedure will only take a few minutes, changes in conductivity can be tracked over time scales appropriate for following abnormal physiological changes associated with stroke, epilepsy, and head injury. PROPOSED COMMERCIAL APPLICATION: The head conductivity scanner will be a useful and necessary addition to any research or clinical EEG/MEG lab that utilizes quantitative inverse methods, alone or in conjunction with other functional imaging modalities such as PET,SPECT, or fMRI.

使用高密度EEG和MEG的精确电生理神经成像越来越需要头部几何形状和电导率的知识。头部和大脑的几何形状可以从结构断层摄影技术，如CT和MRI，但不同的头部组织的导电性目前无法测量。我们建议证明的可行性，测量人类头皮，颅骨和大脑的电导率非侵入性使用低电平头皮电流注入技术。该过程将首先用计算机模拟建模，包括噪声和测量误差的影响。原型硬件将被构造为提供必要的开关和电流注入电路，然后用具有已知几何形状和电导率的物理模型进行测试。最后，将整个系统应用于人体受试者，以展示其整体的实用性。通过精确的电导率，可以为个体受试者或患者构建逼真的头-脑模型，使得用于神经活动时空定位的EEG/MEG逆过程也更加准确。此外，由于电导率估计过程将仅花费几分钟，因此电导率的变化可以在适合于跟踪与中风、癫痫和头部损伤相关联的异常生理变化的时间尺度上被跟踪。拟定商业应用：头部电导率扫描仪将是一个有用的和必要的除了任何研究或临床EEG/MEG实验室，利用定量反演方法，单独或与其他功能成像方式，如PET，SPECT，或fMRI。