School of Mechanical Engineering, Shandong University, Jinan, 250061, PR China.
Microvasc Res. 2011 Nov;82(3):304-10. doi: 10.1016/j.mvr.2011.08.004. Epub 2011 Aug 22.
The objective of this study is to assess the correlation between the prefrontal cerebral oxygenation oscillations measured by near-infrared spectroscopy (NIR) and cerebral artery hemodynamic parameters as measured by transcranial Doppler (TCD). A total of thirty subjects were recruited from the university to participate in this study. The cerebral oxygenation signal and TCD hemodynamic parameters were monitored on separate days. The cerebral oxygenation signal was monitored for 10 min from the left prefrontal lobe using NIRS. TCD monitoring was performed to measure the hemodynamic parameters including end diastolic, peak systolic, and mean cerebral blood flow velocities. Pulsatility index (PI) and resistance index (RI) were calculated automatically. With spectral analysis based on wavelet transform of NIR signal, five frequency intervals were identified (I, 0.005-0.02 Hz, II, 0.02-0.06 Hz, III, 0.06-0.15 Hz, IV, 0.15-0.50 Hz and V, 0.50-2.0 Hz). Significant negative correlation was found between the cerebral [Hb] and [HbO(2)] oscillations in frequency intervals from I to V and the PI or RI in left external carotid artery (ECA) (p<0.005). Also weak negative correlation was found between the cerebral [Hb] and [HbO(2)] oscillations in frequency intervals III, IV, V and the mean velocity in left middle cerebral artery (MCA) (p<0.05). The results suggested that the cerebral oscillations measured from the frontal lobe were closely related to the pulsatility of ECA and reflect partly the vessel stiffness of MCA.
本研究旨在评估经颅多普勒（TCD）测量的大脑动脉血流动力学参数与近红外光谱（NIR）测量的前额叶脑氧合振荡之间的相关性。从大学招募了 30 名受试者参与这项研究。在不同的日子里监测脑氧合信号和 TCD 血流动力学参数。使用 NIRS 从左前额叶监测脑氧合信号 10 分钟。进行 TCD 监测以测量血流动力学参数，包括舒张末期、收缩期峰值和平均脑血流速度。自动计算搏动指数（PI）和阻力指数（RI）。基于 NIR 信号的小波变换的谱分析，确定了五个频率间隔（I，0.005-0.02 Hz，II，0.02-0.06 Hz，III，0.06-0.15 Hz，IV，0.15-0.50 Hz 和 V，0.50-2.0 Hz）。发现从 I 到 V 的频率间隔内大脑 [Hb] 和 [HbO(2)] 振荡与左颈外动脉（ECA）的 PI 或 RI 之间存在显著负相关（p<0.005）。还发现，在频率间隔 III、IV 和 V 中，大脑 [Hb] 和 [HbO(2)] 振荡与左大脑中动脉（MCA）的平均速度之间存在微弱的负相关（p<0.05）。结果表明，从额叶测量的脑振荡与 ECA 的搏动性密切相关，部分反映了 MCA 的血管僵硬度。
