Role of cerebral artery Doppler velocimetry in neonatal hypoxic ischemic encephalopathy

Abstract

Background: Hypoxic ischemic encephalopathy (HIE) is a brain injury that prevents adequate blood flow to the infant’s brain. As compared to MRI and CT scan, neurosonogram is easily available, cost effective and easily reproducible, and is not associated with any radiation exposure or sedation. Therefore, the present study was conducted to assess the role of neurosonogram changes in grey scale and Doppler findings in evaluation of HIE.Methods: It was a hospital-based case control study conducted over a period of one year in which 35 full term neonates born after 37 weeks of gestation with birth weight more than 2.5 kg and clinical evidence of HIE based on Sarnat and Sarnat classification were selected as cases. The 35 neonates other than HIE were matched by age and sex with the cases within 72 hours of birth were labelled as control.Results: On doppler USG both resistive index (RI) and pulsatilitiy index (PI) in anterior cerebral artery (ACA) as well as middle cerebral artery (MCA) were significantly lower in HIE subjects compare to control group while peak systolic velocity (PSV) and end diastolic velocity (EDV) were significantly higher in HIE subjects. There was significant association of RI, PI and EDV with severity of HIE.Conclusions: Spectral doppler imaging has very high sensitivity and specificity in diagnosis as well as grading of HIE. Therefore, it is recommended that in all neonates with clinical suspicion of HIE, neurosonogram along with spectral doppler of cranial arteries should be done for evaluation of HIE.