Magnetic Resonance Diffusion Tensor Imaging (DTI) On The Assessment Of Cerebral Myelination Value

Objective :To explore the magnetic resonance diffusion tensor imaging DTI(FA value and ADC value)characteristics of premature white matter myelination process evaluation and law;comparative study of DTI imaging of the same age(corrected gestational age)preterm and full-term infants myelination difference;provide imaging basis for preliminary explore the pathogenesis of white matter damage in premature infants brain.Materials and methods: A total of 106 patients(including women aged 53 weeks and 36 weeks)were enrolled in this study,And all the subjects were scanned by SIEMENS 1.5T magnetic resonance scanner.The scanning sequence was scanned by conventional transverse axis Tl WI,T2 WI,FLAIR,DWI and DTI sequences.Inclusion criteria for subjects:(1)Corrected fetal age at 32 to 40 weeks of neonatal treatment;(2)The neonatal Apgar score was between 6-10 points,and the neonatal doctor had no significant symptoms or signs of the central nervous system;(3)By two attending or deputy director of radiation diagnostic physician on children with MR images of double-blind reading,the same conclusion for the MRI routine sequence was not found significant positive lesions.(CA)for 32 weeks for A1 group(17 patients),corrected gestational age(CA)for 33 weeks for the A2 group(16),to correct the fetal(CA)weeks to correct the gestational age(CA)(CA)for 34 weeks for A3 group(18 patients),corrected gestational age(CA)for 35 weeks for the A4 group(17),corrected gestational age(CA)for 36 weeks for the A5 group(18)CA)≥40 weeks term for children A0 group(20).Another group of 8 premature infants in the correction of gestational age 40 weeks review,the data as B1 group(8),gestational age of 40 weeks full term children B2(8).The ROI of the corpus callosum was measured,and the FA and ADC values of ROI were measured in 8 cases of the corpus callosum knee,corpus callosum pressure,bilateral lateral ventricle posterior parietal white matter,bilateral internal capsule hind limbs and bilateral semi-oval centers.The statistical differences between FA and ADC values of ROI were examined by paired test,t test and variance analysis.Results: There was no significant difference in ADC value and FA value between male and female(P≥ 0.05).There was no significant difference in ADC value and FA value between left and right symmetrical ROI(P≥0.05).The FA value increased with the increase of gestational age,while the ADC value decreased with the increase of gestational age(P<0.05).The FA value of ROI in different gestational age groups was significantly different,That FA value was positively correlated with gestational age,ADC value was negatively correlated with gestational age(P≥ 0.05).There was no significant difference in the ADC value and FA value between the preterm infants(group B1)and the gestational age(group B2)(P≥0.05).There was no difference in the ADC values between the two groups ROI(posterior hind limb,lateral ventricle posterior parietal white matter and semi-oval center)Statistical difference(P≥0.05).There were significant differences in the values of ROI between the two groups(P≥0.05).The ADC values of the ROI of the corpus callosum were significantly different(P<0.05).The ADC value of ROI in the corpus callosum was higher than that in the corpus callosum(P<0.05).Conclusion: DTI(FA,ADC)can reflect the development and evolution of premature brain myelination;40 weeks after the corrected gestational age in preterm infants than in full-term infants compared with the myelination process may exist relative lag.