Diffusion Tensor Imaging Combined With Fetal Blood Flow Spectrum Evaluates Brain Development In Preterm Infants Born To Mother With Preeclampsia

ObjectivePreeclampsia（PE）,a relatively common complication of pregnancy,can often lead to neurodevelopmental disorders in offspring.To investigate the predictive value of diffusion tensor imaging（DTI）combined with fetal blood flow spectroscopy in infant brain developmental delay caused by PEMaterials and Methods1 Research objects and groupingA total of 271 newborns who underwent DTI in the imaging department of our hospital from July 2015 to January 2020 were selected.Ninety-five cases were excluded because of genetic metabolic diseases,term infant and their mothers suffering from other gestational diseases.And the remaining 176 preterm infants were further followed up and neonatal neurobehavioral scores（NBNA）were collected,and 56 cases who were older at the time of DTI and lacked NBNA were excluded,finally 80 preterm infants delivered by pregnant women with preeclampsia were included as the PE group,with gestational week from 28⁺⁴ to 32⁺¹ weeks,Ninety-six preterm infants delivered by pregnant women without high-risk perinatal factors were included as the control,with gestational week from 29⁺² to 31⁺⁶.All preterm infants underwent DTI examination at corrected gestational age of 32 to 38 weeks.2 Research MethodsRetrospective analysis of maternal and preterm clinical data,and measurement of fractional anisotropy（FA）values of 7 ROI were measured,including posterior limbs of internal capsule（PLIC）,splenium of the corpus callosum（SCC）,superior frontal gyrus（SFG）,superior parietal lobule（SPL）,superior occipital gyrus（SOG）,cerebral peduncle（CP）and dentate nucleus（DN）.Retrospective analysis of maternal and preterm clinical data,Systolic/diastolic velocity ratio of umbilical and middle cerebral artery（UA-S/D and MCA-S/D）,the pulsatility index of umbilical and middle cerebral artery（UA-PI and MCA-PI）,and their ratios（UA/MCA）-S/D and（MCA/UA）-PI.The fetal flow spectrum values and FA values between the two groups were compared;the correlation between FA values of PLIC and fetal blood flow spectrum in the PE group was performed;the correlation between FA values and NBNA scores was analyzed.3 Statistical methodsData were analyzed using SPSS 25.0 and Graph Pad Prism 8.0.2 software.The measurement data were expressed as x±s,and the data were compared between groups by independent samples t-test or nonparametric test.Count data were expressed as the number of cases,and rate values were compared using theχ2 test.Correlation analysis of fetal blood flow spectrum with FA values after adjusting for other factors（of gestational weeks,birth weight,day age at the DTI examination,Duration of assisted respiratory therapy,and weight gain during pregnancy）;correlation analysis of FA values with NBNA scores.The above P<0.05 was considered statistically significant.4 Results4.1 Comparison of the general conditions of pregnant women and newborns between two groupsNo statistically significant differences were found in age,gestation,delivery,miscarriage,pregnancy weight gain,amniotic fluid abnormality rate,prenatal corticosteroid application rate and amniotic fluid contamination rate between the two groups（P>0.05）.Compared with the control group,the rate of preterm infants born by cesarean section was greater in the observation group（P<0.001）;However,no statistically significant differences were seen between the two groups in gestational weeks,birth weight,age at the DTI examination,Neonatal respiratory distress syndrome（NRDS）,Necrotizing enterocolitis（NEC）,Bronchopulmonary dysplasia（BPD）and congenital heart disease complication rates（P>0.05）;The NBNA scores of premature infants in PE group was lower（P=0.015）.4.2 Differences in fetal period blood flow spectral values and FA values between the two groups in preterm infantsCompared with the control group,UA-S/D,UA-PI and（UA/MCA）-S/D were higher and MCA-PI,MCA-S/D and（MCA/UA）-PI were lower in the PE group（P<0.001）.Compared with the control group,FA values were lower in the SCC,PLIC,SFG,CP and DN in the PE group（P<0.05）.4.3 Correlation between FA values of the posterior limb of the internal capsule and fetal blood flow spectrum values and NBNA scores in preterm infants in the PE groupBefore and after adjustment for other factors（week of gestation at birth,birth weight,age at the time of DTI examination,duration of assisted breathing and weight gain during pregnancy）,there was a more significant positive correlation between MCA-PI and（MCA/UA）-PI and the PLIC（P<0.05）.A more significant positive correlation was found between FA values in the PLIC and SCC and NBNA scores（r=0.78,P<0.001;r=0.53,P=0.0002）;no significant correlation was found between FA values and NBNA scores,such as SFG,CP and DN（P>0.05）.5 ConclusionPre-eclampsia can cause brain developmental delay in preterm infants.Effective detection of fetal blood flow spectra and early DTI examination may be helpful detecting brain developmental delay in preterm infants due to PE at an early stage.