Intracranial Pressure Latency as a Biomarker of Cerebral Vasculature Status

描述(由申请人提供)：颅内压是一种广泛监测的生理信号，适用于各种神经科/神经外科疾病的患者。脑脊液(CSF)和脑血流(CBF)循环系统的丰富病理生理信息被嵌入在脑脊液(CSF)和脑血流(CBF)的波形动力学中。然而，在目前的临床实践中，对颅内压测量的解释基本上只考虑了颅内压的绝对值。我们的总体目标是开发一种临床友好的信号处理方法，从颅内压波形中提取一种新的潜伏期测量，并证明其作为脑血管状态的定量生物标志物的有效性。了解脑血管状态，包括血管收缩、血管扩张和整体血管运动活动，对于治疗和管理脑血管疾病和脑损伤患者非常重要。然而，目前，由于技术限制和伦理考虑，以连续方式直接访问脑血管系统受到阻碍。我们的中心假设是，颅内压脉搏相对于颅外循环定时信号的潜伏期是血压波在脑血管系统中传输的脉搏波速度(PWV)的指示器。 我们提出了两个目的来研究两种ICP潜伏期测量的行为，包括起始潜伏期和P1潜伏期对两种实验干预的响应：二氧化碳挑战和姿势变化。建议的实验程序将有助于确定使用ICP潜伏期测量来指示脑血管变化的真阳性和假阳性方面。 如果得到验证，ICP潜伏期测量可用于持续监测脑血管痉挛发展过程中可能出现的脑血管变化，表征脑血管床的储备，并量化脑血流自动调节的效率。 公共卫生相关性这个项目的目标是开发和验证一种新的颅内压潜伏期测量方法，作为脑血管变化的替代指标。颅内压潜伏期测量可用于连续监测脑血管痉挛发生发展过程中可能出现的脑血管改变，表征脑血管床储备，量化脑血流自动调节的效率。

DESCRIPTION (provided by applicant): Intracranial pressure (ICP) is a widely monitored physiological signal for patients with various neurological / neurosurgical diseases. A wealth of pathophysiological information of cerebrospinal fluid (CSF) and cerebral blood flow (CBF) circulatory systems is embedded in ICP waveform dynamics. Nevertheless, interpretation of ICP measurement in current clinical practice, in large, considers only absolute value of ICP. Our overall goal is to develop a clinically friendly signal processing method for extracting a novel latency measure from ICP waveform and demonstrate its effectiveness as a quantitative biomarker of status of cerebral vasculature. Knowledge of cerebral vasculature status including vasoconstriction, vasodilatation, and overall vasomotor activity is important in treating and managing patients with cerebral vascular disorders and brain injury. However, direct access of cerebral vasculature in a continuous fashion is currently hindered by technical limits and by ethic considerations. Our central hypothesis is that latency of an ICP pulse relative to an extracranial circulatory timing signal is an indicator of pulse wave velocity (PWV) of blood pressure wave transmission in the cerebral vasculature. We propose two aims to study the behavioral of two ICP latency measures including the onset and the P1 latency in response to two experiment interventions: CO2 challenge and postural changes. The proposed experiment procedures will help determine the true positive and false positive aspect of using ICP latency measures for indicating cerebrovascular changes. If validated, the ICP latency measure could be useful in continuously monitoring cerebral vasculature changes that could be present in the development of cerebral vasospasm, in characterizing the reserve of cerebral vascular bed, and in quantifying the efficiency of cerebral blood flow autoregulation. PUBLIC HEALTH RELEVANCE The objectives of this project are to develop and validate a novel ICP latency measure as a surrogate of cerebrovascular changes. The ICP latency measure could be useful in continuously monitoring cerebral vasculature changes that could be present in the development of cerebral vasospasm, in characterizing the reserve of cerebral vascular bed, and in quantifying the efficiency of cerebral blood flow autoregulation.