基于经颅多普勒超声的脑血流自动调节临界关闭压机制研究

As widely regarded as the key point of cerebral blood flow regulation, cerebral autoregulation(CA) with its clinical function assessment plays a critical role in individual management of blood pressure of patients with hypertension disease. Due to the defect of classic theory of CA, its clinical function assessments based on transcranial Doppler (TCD) suffer great limitations. In the prophase work, we found that the value of lower limit of cerebral autoregulation derived from critical closing pressure (CCP) by means of TCD was identical with that by classical method. Previous studies also demonstrated that CCP is right the effective lower pressure of cerebral circulation. Based on above, we presume that CA works due to the variance in vascular tone, namely CCP, instead of vascular radius which was discussed in the classical theories of CA. In this study, we will monitor the variables such as cerebral blood flow, CCP and microvascular radius synchronously and consecutively using TCD and the measurement technique of microvascular diameter. Furthermore, we will process all the signs from monitoring system synchronously with Matrix Laboratory to assess the worth of CCP in CA and discuss its potential working mechanism. We aim to establish a new theory of critical closing pressure of CA, develop the practical measurement technique of cerebral regulation by TCD and guide the individual management of blood pressure, and then expand the applied scope of TCD and advance prevention and therapy of cerebrovascular disease.

脑血流自动调节是脑血流调控的关键所在，其临床功能评价对个体化血压调控至关重要。但经典理论的不足，制约了经颅多普勒超声等检测手段对脑血流自动调节功能的临床评价。我们前期工作发现，利用临界关闭压测定的脑血流自动调节下限结果和经典方法高度吻合；相关研究也表明临界关闭压是脑循环的有效下游压。我们推测，脑血流自动调节主要是通过血管紧张度即临界关闭压改变、而不是经典理论所述的血管半径改变完成的。本项目拟采用经颅多普勒超声，结合微血管直径测量系统等技术，同步监测脑血流、临界关闭压和微血管半径等连续信号，利用矩阵实验室（MATLAB）进行多路信号同步处理，系统评价和阐明临界关闭压在脑血流自动调节过程中对脑血流的调控作用和机制。为构建脑血流自动调节临界关闭压学说、开发实用的经颅多普勒超声脑血流调控评价技术、指导个体化血压调控奠定坚实的理论和方法学基础，进而拓展经颅多普勒超声应用领域、提高脑血管病防治水平。

脑血流自动调节是脑血流调控的关键所在，其临床功能评价对个体化血压调控至关重要。但经典理论的不足，制约了经颅多普勒超声等检测手段对脑血流自动调节功能的临床评价。我们前期工作发现，利用临界关闭压测定的脑血流自动调节下限结果和经典方法高度吻合；相关研究也表明临界关闭压是脑循环的有效下游压。我们推测，脑血流自动调节主要是通过血管紧张度即临界关闭压改变、而不是经典理论所述的血管半径改变完成的。本项目拟采用经颅多普勒超声，结合微血管直径测量系统等技术，同步监测脑血流、临界关闭压和微血管半径等连续信号，利用矩阵实验室（MATLAB）进行多路信号同步处理，系统评价和阐明临界关闭压在脑血流自动调节过程中对脑血流的调控作用和机制。为构建脑血流自动调节临界关闭压学说、开发实用的经颅多普勒超声脑血流调控评价技术、指导个体化血压调控奠定坚实的理论和方法学基础，进而拓展经颅多普勒超声应用领域、提高脑血管病防治水平。