Objective To measure the cerebral hemodynamics of neonatal respiratory distress syndrome（NRDS） by two-dimensional and Doppler ultrasound

and to provide references for early clinical diagnosis and prevention of brain damage secondary to NRDS.Methods A total of 123 neonates borned in the obstetrics department of our Hospital were prospectively divided into three groups

including 42 NRDS infants（case group）

49 healthy full-term infants（full-term group）

and 32 healthy premature infants（premature group）.All neonates underwent cerebral ultrasonic examination in 24-48 h after birth

the thickness of the frontal lobe and transverse diameter were measured

parenchymal hemorrhage or not was observed

and the blood flow spectrum parameters of middle cerebral artery（MCA） including the peak systolic velocity（PSV）

end-diastolic velocity（EDV）

mean flow velocity（MFV）

resistance index（RI） and pulse index（PI） were measured.Among the 42 neonates in case group

25 of them received exogenous pulmonary surfactant（PS） and craniocerebral ultrasound was re-examined after 1 d treated with the drug.Results Two-dimensional craniocerebral ultrasound showed that

there were statistically significant differences among the three groups in cerebral transverse diameter

frontal lobe thickness and periventricular echodensity（all P<0.001）.Transcranial Doppler ultrasound showed that compared with the full-term group

EDV

MFV and PSV of the premature group were decreased

while RI and PI were increased（all P<0.05）.Compared with the full-term group

PSV

EDV and MFV of the case group were significantly decreased（all P<0.001）

while RI and PI showed no significant changes.Compared with the premature group

there were no significant changes of cerebral blood flow velocity

RI and PI of the case group.After treatment of exogenous PS

PSV and RI of 25 neonates in case group were significantly lower than those before treatment（all P<0.05）

while EDV

MFV and PI showed no significant changes.Conclusion Two-dimensional and Doppler ultrasound could clearly show the neonatal brain parenchyma

effectively detect the changes of cerebral blood flow velocity

and provide reference for early clinical diagnosis and prevention of brain injury in neonates with NRDS.