大脑中动脉中央支血流动力学评价新生儿缺血缺氧性脑病

目的探讨新生儿缺血缺氧性脑病（HIE）不同时期大脑中动脉中央支血流动力学变化及其相互关系，为临床诊断HIE提供
新的参考依据。方法将2013年3~7月在我中心儿童院区临床确诊为HIE的136例患儿作为实验组，进行二维超声检查并应用
彩色多普勒超声测定大脑中动脉中央支收缩期血流速度（Vs）及阻力指数（RI），与作为对照组的251例正常足月儿的大脑中动脉
中央支声像图比较，并对血流参数进行统计分析。结果实验组超声声像图显示轻度HIE患儿脑水肿仅脑室周围白质增强，中、
重度HIE患儿出现双侧脑半球回声弥漫性增强，脑结构回声模糊，清晰度降低。实验组轻度、中度和重度HIE患儿脉冲多普勒
检测大脑中动脉中央支血流动力学与对照组比较，表现为Vs降低，RI升高，与对照组比较均有统计学意义（P<0.05），且轻度与
中、重度HIE患儿之间Vs和RI比较有显著差异（P<0.05），中度与重度HIE患儿之间Vs和RI比较无显著差异（P>0.05）。结论超
声检查能够动态观察HIE患儿颅内二维形态、回声改变及脑血流灌注特点，大脑中动脉中央支能够清晰准确反映患儿脑血流灌
注情况，为早期诊断脑水肿，早期进行临床干预提供有价值的依据。

Evaluation of neonatal hypoxic-ischemic encephalopathy by ultrasound measurement of the hemodynamics in the central branches of the middle cerebral artery

Objective To evaluate the hemodynamic changes in the central branches of the middle cerebral artery in different
stages of neonatal hypoxic-ischemic encephalopathy (HIE) and provide new evidence for clinical diagnosis of HIE. Methods
From March, 2013 to July, 2013, a total of 136 newborn infants were diagnosed to have HIE in our center. We performed
two-dimensional ultrasonography and color Doppler ultrasound for assessments of systolic velocity (Vs) and resistant index
(RI) of the central branches of the middle cerebral artery. The data were compared with the results of a control group
consisting of 251 normal full-term infants. Results Infants with mild HIE showed hyperechoic changes in the white matter
around the ventricle, while in moderate and severe HIE, such hyperechoic changes were diffuse in both hemispheres with
unclear echoes of the brain structures. Pulse Doppler assessments of hemodynamics of the central branches of the middle
cerebral artery demonstrated a significant decrease in Vs and an increase in RI regardless of HIE severity (P<0.05). In addition,
Vs and RI values in mild HIE infants differed significantly (P<0.05) from those in infants with moderate and severe HIE, who
had comparable Vs and RI values (P>0.05). Conclusion Transcranial ultrasonography may provide dynamic information on
cerebral blood flow in neonates and hemodynamic parameters of the central branches of the middle cerebral artery are
valuable for clinical diagnosis and early intervention of HIE.