Comparative Study Of Magnetic Resonance Imaging (MRI) Multi-sequence Combination And Ultrasound (US) In Neonatal Hypoxic-ischemic Encephalopathy (HIE)

Objectives:(1)To investigate the ideal MRI sequence combination for the diagnosis of neonatal HIE through the application of different MRI scanning sequences in neonatal hypoxic-ischemic encephalopathy(HIE).(2)To explore the optimized diagnostic method through comparing multiple sequence combination of MRI with ultrasound(US)in the diagnosis of neonatal HIE.Methods:A retrospective analysis was performed on the full-term neonates with clinical suspicion of HIE in North hospital of the No.1People's Hospital of ChenZhou(children's hospital)affiliated to University of South China from January 1,2017 to July 1,2018.According to the inclusion criteria and exclusion criteria,100 neonates with suspected HIE were selected from 283 neonates of this study,which include 55 male cases and 45 female cases and their gestational ages are between 37-42 weeks.According to the diagnostic criteria and clinical grading of neonatal HIE established by the Neonatal Group of the Society of Pediatrics,Chinese Medical Association in 2005?1?,100 neonates with HIE were divided into mild group(88 cases),moderate and severe group(12 cases).At the same time,45 normal full-term newborns were randomly selected to form a control research group,which include 24 male cases and 21 female cases.(1)All were in HIE group and the normal control group infants born within a week to accept MRI,including regular sequences(T1 FLAIR,T2PROP,T2 FLAIR),Diffusion Weighted Imaging(coursing together Weighted Imaging,DWI)and magnetic sensitive Weighted Imaging(Susceptibility Weighted Imaging,SWI).All neonates in mild group and moderate and severe group were divided into four groups according to different sequence combinations(100 persons in each sequence combination):conventional MRI group,conventional MRI+DWI group,conventional MRI+SWI group and conventional MRI+DWI+SWI group.These four groups of imaging data were carefully reviewed by two radiologists with senior professional titles,and the number of HIE positive cases and lesions of neonates detected in each sequence group were recorded respectively,after that the analysis and discussion were made.(2)All newborns in the HIE group and the normal control group completed the first brain ultrasound examination within a week after birth.Apart from using two-dimensional ultrasonography to determine whether there are echo changes in the brain tissue of children,color Doppler and spectral Doppler techniques should be used to know the blood flow of bilateral anterior cerebral artery(ACA)in all patients.What's more,you need to write down the hemodynamic parameters of anterior cerebral artery,including End diastolic velocity(EDV),Peak systolic velocity(PSV)and Resistance index(RI),and compare the differences of hemodynamic parameters among mild,moderate and severe research groups and control research groups.(3)The sensitivity,accuracy and specificity of conventional MRI+DWI+SWI sequence combination and ultrasound in the diagnosis of neonatal HIE were compared.Results:1 The results of MRI examination:All neonates in mild group and moderate and severe group were examined by conventional MRI+DWI+SWI multi-sequence combined scan.The results are as follows:(1)64 Cases of Brain Edema;(2)There were 23 cases showed Short T1 signal in cortex,subcortex and deep white matter,which needed considering selective neuronal necrosis;(3)10 cases of thalamic basal ganglia injury;(4)3 cases of parasagittal injuries;(5)3 cases of periventricular leukomalacia;(6)3 cases of cerebral infarction;(7)8 cases of intraventricular hemorrhage;(8)26 cases of subependymal hemorrhage;(9)14 cases of cerebral parenchymal hemorrhage;(10)14 cases of subdural hemorrhage;(11)13 cases of subarachnoid hemorrhage;(12)8 cases of cerebellar hemorrhage;(13)2 cases of venous dilatation.Among the 100 neonates with HIE,there were 46positive cases detected by routine MRI sequence and 121 lesions were detected.There were 66 positive cases and 147 lesions detected by routine sequence and DWI combination.There were 69 positive cases and 152lesions detected by routine sequence and SWI combination.There were 85positive cases and 178 lesions detected by routine sequence plus DWI+SWI combination.Byc~2 test analysis of routine MRI sequence+DWI,routine sequence MRI+SWI combination of neonatal HIE detection of positive rate was obviously higher than conventional MRI sequences(P<0.05,the difference was statistically significant).routine MRI sequence+DWI+SWI can combination for neonatal HIE positive rate of detection is higher than conventional MRI sequences and other sequences(P<0.05,the difference was statistically significant).The MRI results of 45 neonates in the control group showed that 2 of them had abnormal signals,with slightly longer T1 and T2 signals in the frontal and parietal lobes.2 The results of craniocerebral ultrasonography:Among 88 cases of neonatal HIE mild group,55 cases were found abnormal,mainly manifested as bilateral paraventricular white matter echo enhancement,echo lower than choroid plexus,suggesting mild parenchymal edema.Twelve of them had subependymal hemorrhages or hemorrhagic cystic degeneration(Subependymal hemorrhages,SEH).There were 4 cases of intraventricular hemorrhage(Intraventricular hemorrhage,IVH).Among12 neonates with HIE in moderate and severe groups,abnormal echoes were found in 10 cases by two-dimensional craniocerebral ultrasound.The echo intensity of bilateral paraventricular white matter was equal to or higher than that of choroid plexus or the echo of brain parenchyma increased diffusely.Thalamus,cortex and subcortex accumulated in basal ganglia.The whole structure of brain tissue was not clearly displayed and the boundary between sulcus and gyri was blurry.The ventricles and fissures become narrow,slit-like changes,and even can not be shown under ultrasound.There were 6 cases of thalamic basal ganglia injury(TBGI).There were 3 cases of bilateral parenchymal lesions showed inhomogeneous strong echoes with patchy and granular distribution,which would last one week,and the disappeared ventricular system reappeared.In this situation,we often considered choosing the Selective neuronal necrosis(SNN).There were 1case of left temporal occipital lobe hemorrhage.There were 3 cases of subependymal hemorrhage or hemorrhagic cystic degeneration.There were 2cases of right occipital lobe demarcation infarction.There were 2 cases of Periventricular leukomalacia(PVL).The number of children in the control group was 45 in total.The echo of bilateral paraventricular white matter was enhanced in 4 cases by two-dimensional craniocerebral ultrasound,and the echo was lower than choroid plexus.3 The results of Color Doppler and Spectrum Doppler Ultrasound Observation of Blood Flow Spectrum of Bilateral Anterior Cerebral Artery:All 145 neonates in the mild,moderate and severe groups and the control group were examined by two-dimensional craniocerebral ultrasonography.Color doppler and spectral doppler techniques were used to detect the cerebral blood flow distribution and resistance of bilateral anterior cerebral arteries.The results were as follows.There were significant differences in PSV and EDV between the three groups(P<0.05).The RI values of moderate and severe neonatal HIE group were significantly different from those of the control group(P<0.05).RI value of mild neonatal HIE group was significantly different from that of control group(P<0.05).It indicates that the worse the HIE condition of the newborn,the lower the corresponding PSV value and EDV value,and the higher the RI value.4 Features of routine MRI+DWI+susceptibility sequence and ultrasound in the diagnosis of neonatal HIE:In the diagnosis of neonatal HIE,the accuracy,sensitivity and specificity of routine MRI+DWI+susceptibility and US were 88.28%,85.00%,95.56%and 73.10%,65.00%and 91.11%,respectively.5 the detection of lesions in the diagnosis of neonatal HIE by conventional MRI+DWI+SWI multi-sequence combination and ultrasound:(1)In the mild group,the multi-sequence combination of ultrasound and MRI had a slightly higher coincidence rate in terms of cerebral edema,intraventricular hemorrhage and subependymal hemorrhage,with a distribution of 98.18%,50%and 60%.No lesions were found by ultrasound in selective neuronal necrosis,para-sagittal area injury,cerebral parenchymal hemorrhage,subdural hemorrhage,subarachnoid hemorrhage,cerebellar hemorrhage,venous dilation,etc.,while lesions were found in all MRI multi-sequence combinations.(2)In the moderate and severe groups,the multi-sequence combination of ultrasound and MRI had slightly higher coincidence rates in terms of cerebral edema,thalamic basal ganglia injury,leukomalacia,cerebral infarction,intraventricular hemorrhage and subependymal hemorrhage(60%,60%,100%,66.67%,50%and 50%respectively).The selective neuronal necrosis and cerebral parenchymal hemorrhage were 33.33%and 20%,respectively.Ultrasound showed no lesions in para-sagittal lesions,subdural hemorrhage,subarachnoid hemorrhage,cerebellar hemorrhage,venous dilatation,etc.,while MRI showed lesions in multiple sequences,especially in veins with more dilatation.(3)In mild and moderate and severe neonates,the combination of ultrasound and MRI multiple sequences in cerebral edema and periventricular leukomalacia compliance rate were relatively high(95.31%and 100%,respectively).The coincidence rates of basal ganglia injury,cerebral infarction,intraventricular hemorrhage and subependymal hemorrhage were slightly higher(60%,66.67%,50%,57.96%).The selective neuronal necrosis and cerebral parenchymal hemorrhage were13.04%and 7.14%,respectively.Ultrasound showed no lesions in subdural hemorrhage,subarachnoid hemorrhage,cerebellar hemorrhage,venous dilatation,etc.,while MRI showed lesions in multiple sequences,especially in veins with more dilatation.6 The results of positive rate of neonatal HIE by routine MRI+DWI+SWI multi-sequence combination and ultrasound were as follows:Among all the neonates in the mild group and the moderate and severe groups,a total of 85 positive cases were detected by MRI routine sequence+DWI+SWI,and 65 cases were detected by ultrasound.After statistical analysis,the detection rate of HIE positive rate of neonates by conventional MRI+DWI+SWI was significantly higher than that by ultrasound(P<0.05,the difference was statistically significant).Conclusion:?In the diagnosis of neonatal HIE,the diagnostic effect of conventional MRI+DWI+SWI combined with multiple sequences is better than that of ultrasound.?Compared with conventional MRI,conventional MRI+DWI+SWI can improve the diagnostic effect of HIE.