Reliability, asymmetry, and age influence on dynamic cerebral autoregulation measured by spontaneous fluctuations of blood pressure and cerebral blood flow velocities in healthy individuals.
Reliability, asymmetry, and age influence on dynamic cerebral autoregulation measured by spontaneous fluctuations of blood pressure and cerebral blood flow velocities in healthy individuals.
复制标题
DOI：
10.1111/jon.12019
复制
发表时间：
2014-07
期刊：
影响因子：
--
通讯作者：
Marshall RS
中科院分区：
文献类型：
--
作者：
Ortega-Gutierrez S;Petersen N;Masurkar A;Reccius A;Huang A;Li M;Choi JH;Marshall RS
脑自动调节（CA）使大脑能够维持稳定的脑血流量（CBF）。CA可以通过确定脑血流速度（CBFV）和血压自发变化之间的相关性进行无创评估。记录后信号分析方法包括频域和时域方法。然而，重测信度，交叉验证，并确定正常值尚未充分建立。在53名健康志愿者中，应用传递函数分析来计算CA最明显的低频范围（0.06-0.12 Hz）的相移（PS）和增益。采用相关分析法计算平均流速指数（Mx）。采用组内相关和双变量相关系数评估不对称性、交叉有效性和重测。双半球平均PS、增益和Mx均值分别为45.99+/−14.24度、0.62+/−0.38 cm/sec/mm Hg和0.41+/− 0.13。增重表现出年龄差异（p=0.03）。PS、增重和Mx值显示出极好的半球间相关性（r>0.8; p<0.001）。PS和增益显示出良好的可靠性（RICC =0.632，LICC =0.576; p<0.001）。PS和Mx表现出相当的相关性（r=-0.37; p<0.001）。通过时域和频域方法获得的CA参数相关性良好，并显示出良好的半球间和重测信度。健康对照组的组平均值可能为确定脑血管病患者的异常CA提供足够的标准。
Cerebral autoregulation (CA) enables the brain to maintain stable cerebral blood flow (CBF). CA can be assessed non-invasively by determining correlations between cerebral blood flow velocity (CBFV) and spontaneous changes in blood pressure. Post-recording signal analysis methods have included both frequency- and time-domain methods. However, the test-retest reliability, cross-validation, and determination of normal values have not been adequately established. In 53 healthy volunteers a transfer function analysis was applied to calculate phase shift (PS) and gain in the low frequency range (0.06-0.12 Hz) where CA is most apparent. Correlation analysis was used to derive mean velocity index (Mx). Intra-class correlation and bivariate correlation coefficients were applied to assess asymmetry, cross-validity, and test-retest The bihemispheric average PS, gain and Mx means were 45.99+/−14.24 degrees, 0.62+/−0.38 cm/sec/mm Hg and 0.41+/− 0.13 respectively. Gain exhibited a difference by age (p=0.03). PS, gain and Mx values showed excellent inter-hemispheric correlation (r>0.8; p<0.001). PS and gain showed good reliability (R ICC=0.632, L ICC=0.576; p<0.001). PS and Mx showed fair correlation (r=−.37; p<0.001). CA parameters obtained by time- and frequency-domain methods correlate well, and show good inter-hemispheric and test-retest reliability. Group means from healthy controls may provide adequate norms for determining abnormal CA in cerebrovascular patients.