Diagnostic Value Of Routine T1WI And DKI In Acute Bilirubin Encephalopathy In Term And Near Term Infants

Objective: To investigate the value of evaluating the degree of billirubin brain damage in acute bilirubin encephalopathy in term infants and near term infants by using conventional T1-weighted imaging and diffusion kurtosis imaging.Materials and Methods: Retrospective random sampling of 20 cases of acute bilirubin encephalopathy in the PACS system,another prospective random 21 newborns with acute bilirubin encephalopathy and 14 normal newborns were included.A total of 55 patients were classified four groups as normal,mild,moderate and severe according to the BIND scoring system.Magnetic resonance axial T1 WI,T2WI,and DWI sequence scans were performed on all subjects in the forward-looking part.Image post-processing workstations were used to measure the ratio of signal intensity of bilateral globus pallidus relative to cerebrospinal fluid(hereinafter referred to as GP /CSF signal intensity ratio)on the T1 WI images.Secondly,in the encephalopathy group,21 newly diagnosed newborns with acute bilirubin encephalopathy and 14 normal volunteers were subjected to the above sequence scan,and the DKI sequence was added to measure the diffuse kurtosis of the bilateral globus pallidus,including MK value,FA value and MD value.The GP /CSF signal intensity ratio and the parameters of diffusion kurtosis imaging were used to compare between groups.The correlations between GP/CSF signal intensity ratio of encephalopathy group and BIND score system were also analyzed.At the same time,the receiver operating characteristic curve of all the measured values were drawn to obtain the best critical value that can identify the normal group and the encephalopathy group.The above statistical processing were all processed by SPSS 22.0 software package.Results: 1.There is a strong positive correlation between GP /CSF signal intensity ratio and the severity of ABE(r=0.778,P<0.001).The greater the ratio,the more severe the ABE condition;the comparison between the four groups showed that there was no statistically significant difference between the mild ABE group and the control group.There were statistical differences between the control group and the moderate ABE group,the control group and the severe ABE group,and between the moderate ABE group and the severe ABE group(P<0.05).2.Compared with the normal group,in the encephalopathy group,the MK and FA of the globus pallidus area decreased,and the difference was statistically significant.The MD value increased,but the difference was not statistically significant.3.Analysis of ROC curve showed AUCGP/CSF=0.719(P = 0.015),corresponding to the most approximate index,sensitivity = 53.7%,specificity = 92.9%;analysis of FA,MK ROC curve showed AUCFA=0.728,AUCMK=0.745(P values=0.024,0.015),corresponding to the most approximate index:FA=0.170,sensitivity FA=76.2%,specificity FA=64.3%;MK=0.379,sensitivity MK=47.6%,specificity MK=92.9%.Conclusions: 1.The GP /CSF signal intensity ratio can be used for the diagnosis and severity assessment of neonatal acute bilirubin encephalopathy.2.DKI imaging can provide more information for the microstructural changes in the globus pallidus area of acute bilirubin encephalopathy.