The Application Value Of DTI In The Development Of Corpus Callosum In Normal Fetus

Objective The DTI technique was used to quantitatively evaluate the subtle structural changes of corpus callosum development in normal fetuses,providing a reference standard for early evaluation of corpus callosum maturity.Methods 102 normal pregnant women（age 18-43 years,median age 29.5 years）were treated.Fetal age 24-36⁺⁵weeks,median gestational age 31 weeks)routine MRI and DTI scan were performed.According to the gestational age,102 subjects were divided into 7 groups.On the obtained midsagittal DTI image,an appropriate area of interest（ROI）was selected to measure and record the FA and ADC values of the genu,splenium and callosal body of the corpus callosum in 7 different gestational age groups.The changes of FA and ADC values in three subregions of corpus callosum were statistically analyzed with the increase of gestational age.Results There was no statistically significant difference between male and female between the three subregions of corpus callosum in 102 normal fetuses at different gestational ages,P>0.05.There was no statistically significant difference in FA value and ADC value between the three subregions of different gestational age groups（P>0.05）.The difference of FA value and ADC value in three subregions of corpus callosum in different gestational age groups was statistically significant（P<0.05）.The FA values and ADC values of the three subregions had regional differences,and it was concluded that the FA values of the three subregions were,from large to small,splenium>genu>callosal body,and the ADC values were,from large to small,genu>splenium>callosal body.The range of FA values in the three subregions of corpus callosum was 0.34-0.963,and the range of ADC values was 1.153-1.591mm²/s.With the increase of gestational age,FA values in the three subregions of corpus callosum increased and ADC values decreased.Conclusion DTI technology can quantitatively evaluate the subtle structural changes in fetal corpus callosum development,and provide a reference standard for early evaluation of corpus callosum development maturity.The FA value and ADC value of the three subregions of corpus callosum changed regularly with the increase of gestational age,which can reflect the embryonic development order of corpus callosum.