Application Of Magnetic Resonance Diffusion Tensor Imaging In Evaluation And Prognosis Of Infants With Hypoxic Ischemic Encephalopathy

BackgroundPerinatal hypoxic asphyxia can cause hypoxic-ischemic brain damage,can result in various degrees of backward motor development,epilepsy,mental retardation,even can develop into cerebral palsy in severe cases.Cerebral palsy seriously affects the life and survival quality in children,and causes serious burden and harm to family and society.Brain magnetic resonance(MRI)has been shown to be effective in assessing brain injury in children with HIE.Conventional MRI examination can only demonstrate intracranial lesions in some children or without abnormality.Moreover,routine MRI could not quantitatively assess microstructure and the damage of white matter nerve fibers.Our study tried to quantitatively assess the degree of hypoxic-ischemic encephalopathy(HIE)children using MRI diffusion tensor imaging(DTI),and find specific imaging markers to predict prognosis,which can provide reference and basis for early clinical intervention and have great clinical and social significance in reducing the incidence of cerebral palsy.ObjectiveTo explore the application value of DTI in the evaluation and prognosis prediction of hypoxic ischemic encephalopathy in infants,and guide early clinical intervention.MethodsFrom December 2016 to December 2018,40 children under 2 years old with a history of hypoxia and ischemia at birth were selected and underwent MRI plain scan and DTI in the First Affiliated Hospital of Henan University of Chinese Medicine.According to the follow-up results,40 children were divided into the cerebral palsy group and the non-cerebral palsy group,20 cases for every group respectively,and the ages of children in the two groups were strictly matched.Recorded and scored the signs of routine brain scan(Signal anomaly recorded as 1,signal nomaly recorded as 0).On DTI images,regions of interest(ROI)was delineated and fractional anisotropy(FA)and apparent diffusion coefficient(ADC)were measured.Brain white matter area included:cereburm peduncle,anterior limb of internal capsule(ICAL),genu of internal capsule(ICG),posterior limb of internal capsule(ICPL),centrum semiovale,corticospinal tract(CST),lower longitudinal tract(ILF),posterior thalamic radiation(PTR),visual radiation(OR),auditory radiation(AR),genu of corpus callosum(GCC),body of corpus callosum(BCC),splenium of corpus callosum(SCC),white matter of frontal lobe(FLWM),white matter of parietal lobe(PLWM)?Gray matter area:anterior cingulum(ACG),posterior cingulum(PCG).Gray matter nuclei:lenticular nucleus(LN),caudate nucleus(CN),thalamus.The differences of FA and ADC values between the two groups were compared by two independent sample t tests,and three-dimensional image of CST and corpus callosum were compared.used?~2 test to compare the difference of plain scan signs between the two groups;two independent sample t tests to compare the FA and ADC values between the two groups.Multiple factors Logistic regression analysis to screen the independent influencing factors of cerebral palsy.Used the Hosmer-Lemeshow test to evaluate the fitting degree of the model,the effectiveness of the curve evaluation model.Results1.There were no significant differences in age,sex,gestational age and birth weight between two groups(P>0.05).2.MRI plain scan showed there were significant abnormalities in the bilateral centrum semiovale,left thalamus and BCC between the two groups(P?0.05).3.The FA values in paralysis group were lower than those in the non-paralysis group.The FA values of white matter in the two groups were statistically different in bilateral cereburm peduncle,bilateral ICPL,bilateral centrum semiovale,bilateral CST,bilateral ILF,bilateral PTR,bilateral OR,bilateral AR,GCC,BCC,SCC,bilateral PLWM and left LN(P?0.05).4.The ADC values between the two groups were statistically different in the left ICPL,bilateral centrum semiovale,bilateral CST,left PTR,BCC,SCC,left PLWM and left thalamus(P?0.05).5.The results of multiple factors logistic regression analysis:the FA value of left CST,the FA value of left ICPL and the FA value of SCC were independent prognoses of cerebral palsy.Area under the ROC curve of prognoses of cerebral palsy was 0.898 by the combination of three,the sensitivity and specificity were 85.23%and 90.49%,accuracy was 0.772.Conclusions1.Ischemic hypoxic brain injury can cause various degrees of damage to the white matter fiber bundle.The FA value of cerebral palsy group decreased,the ADC value increased,but the FA value is more sensitive,so it should be paid more attention as a focused parameter.2.The FA value of left CST,the FA value of left ICPL and the FA value of SCC were independent prognoses of cerebral palsy,so they should be paid more attention as focused parameters and areas.3.Diffusion tensor imaging can reflect the development and damage degree of nerve fiber bundle,and can provide reliable evidence for evaluation and prognosis judgment of children with HIE,and guide the early clinical intervention.